Abstracts 2018

Headaches in Loeys-Dietz Syndrome.
Samanta D
J Child Neurol. 2018 Dec 19:883073818815039. [Epub ahead of print]
Abstract
Loeys-Dietz syndrome is a rare connective tissue disorder characterized by cardiovascular, craniofacial, skeletal, and neurocognitive abnormalities. Recurrent headaches may constitute the neurological presentation of Loyes-Dietz syndrome in the absence of an intracranial aneurysm, subarachnoid hemorrhage, or dissection. The etiology of headaches occurring in Loeys-Dietz syndrome can be diverse but underrecognized and underreported. We described 3 children with Loeys-Dietz syndrome and significant headaches who did not develop neurovascular aneurysms or dissections at presentation and during the short follow-up period. One patient had a confirmed Loeys-Dietz syndrome diagnosis previously and presented with an acute headache due to spontaneous intracranial hypotension and other 2 children had intermittent headaches due to migraine and Chiari I malformation, respectively, and subsequent diagnosis of Loeys-Dietz syndrome was made due to characteristic phenotypic and neuroradiologic abnormalities. Migraine, Chiari I malformation, and spontaneous intracranial hypotension are known features of Loeys-Dietz syndrome and these 3 children will require serial angiographic monitoring for development of intra- and extracranial dissections and aneurysms and appropriate interventions to forestall neurologic complications. It is important to raise awareness of headaches in this population so that appropriate counseling can be given to the child and parents at diagnosis. The neurology community must familiarize itself with the phenotype of the disease for earlier recognition and meticulous surveillance for optimum care for these patients.
PMID: 30565496
DOI: 10.1177/0883073818815039

Ahn C, Lee E, Lee JW, Chee CG, Kang Y, Kang HS.
J Clin Neurosci. 2018 Nov 26. pii: S0967-5868(18)31673-4. [Epub ahead of print]
Abstract
Spontaneous intracranial hypotension (SIH), caused by CSF leaks, can trigger headaches, and is treated using epidural blood patch (EBP) procedures. We aimed to determine the effectiveness of a newly devised two-site blind EBP procedure as the initial treatment for SIH and compare its effectiveness with that of conventional targeted EBP. We retrospectively reviewed data for 116 patients who underwent EBP for SIH between November 2013 and April 2017. Patients were divided into two groups: those who initially received two-site blind EBP (n = 28) at the cervicothoracic (C7/T1) and thoracolumbar junctions (T12/L1) for sealing CSF leaks at all levels, and those who received targeted EBP after CT myelography (n = 88). The initial recovery status and the need for additional blood patches were evaluated. In total, 71.4% and 69.3% patients in the two-site blind EBP and targeted EBP groups, respectively, experienced complete relief after the first patch (p > .05); collectively, 89.3% and 96.6% patients, respectively, experienced complete or partial relief after the first patch (p > .05). A second EBP was required by 35.7% and 29.5% patients in the two-site blind EBP and targeted EBP groups, respectively, with no significant between-group difference (p > .05). All patients ultimately experienced relief; a few required up to four patches. We observed similar outcomes after initial two-site blind EBP and targeted EBP. Therefore, two-site blind EBP is an effective alternative to conventional targeted EBP and a potential initial patch of choice for SIH treatment.
PMID: 30497854
DOI: 10.1016/j.jocn.2018.11.039

Soares A, Lopes N, Morgado G, Serino J, Painhas T, Almeida C, Vaz F.
Eur J Ophthalmol. 2018 Oct 7:1120672118804791. doi: 10.1177/1120672118804791. [Epub ahead of print]
Abstract
PURPOSE:
The aim of this study is to analyze the lamina cribrosa depth and to study the optic nerve in patients with spontaneous intracranial hypotension.
METHODS:
A total of 10 eyes of the patients with spontaneous intracranial hypotension with unknown etiology (study group) and 10 eyes of healthy patients without any ophthalmological or neurological pathologies (control group) were included. The subjects were submitted to ophthalmological examination with the evaluation of visual acuity, spherical equivalent, applanation tonometry, pachymetry, axial length, retinography, computerized static perimetry (Humphrey 30-2 SITA-Standard), and OCT Spectralis with enhanced depth image, to calculate the depth of the anterior surface of the lamina cribrosa and to measure the nerve fiber layer thickness of the optic nerve. All of these parameters were compared between the two groups.
RESULTS:
Mean anterior surface of the lamina cribrosa depth was 447.96 ± 118.51 (313.30-632.0) μm for the spontaneous intracranial hypotension group and 292.56 ± 40.71 (247-387) μm for the control group, with a statistically significant difference between them (p = 0.001). The thickness of the nerve fiber layer did not differ significantly in the temporal (p = 0.94), nasal (p = 0.173), superior (p = 0.41), central (p = 0.36) or inferior (p = 0.5) sectors. Four eyes of patients with spontaneous intracranial hypotension showed a marked reduction in the temporal nerve fiber layer. Pachymetry (p = 0.16), axial length (p = 0.71), and intraocular pressure (p = 0.6) did not differ significantly between groups, whereas spherical equivalent (p = 0.03) was significantly different. Visual fields were normal in both groups.
CONCLUSION:
The translaminar gradient is determinant in the structure of the lamina cribrosa. Low intracranial pressure associated with a high translaminar gradient leads to an increased lamina cribrosa depth similar to that observed in glaucoma patients.
PMID: 30295059
DOI: 10.1177/1120672118804791

Wu JW, Wang YF, Fuh JL, Lirng JF, Chen SP, Hseu SS, Wang SJ.
Cephalalgia. 2018 Oct 9:333102418804161. doi: 10.1177/0333102418804161. [Epub ahead of print]
Abstract
Objectives Several brain and spinal magnetic resonance imaging signs have been described in spontaneous intracranial hypotension. Their correlations are not fully studied. This study aimed to explore potential mechanisms underlying cerebral neuroimaging findings and to examine associations among spinal and brain magnetic resonance imaging signs.
Methods We conducted a retrospective review of magnetic resonance myelography and brain magnetic resonance imaging records of patients with spontaneous intracranial hypotension. Categorical principal component analysis was employed to cluster brain neuroimaging findings. Spearman correlation was employed to analyze associations among different brain neuroimaging findings and between brain and spinal neuroimaging findings.
Results In patients with spontaneous intracranial hypotension (n = 148), categorical principal component analysis of brain neuroimaging signs revealed two clusters: Cerebral venous dilation and brain descent. Among all brain magnetic resonance imaging signs examined, only midbrain-pons angle associated with anterior epidural cerebrospinal fluid collection length (surrogate spinal cerebrospinal fluid leak severity) (n = 148, Spearman’s ρ = -0.38, p < .001). Subgroup analyses showed that the association between midbrain-pons angle (within brain descent cluster) and spinal cerebrospinal fluid leak severity was presented in patients with convex margins of the transverse sinuses (n = 122, Spearman’s ρ = -0.43, p < .001), but not in patients without convex margins (n = 26, Spearman’s ρ = -0.19, p = .348). The association between severity of transverse sinus distension and spinal cerebrospinal fluid leak severity was only presented in patients without convex margins (n = 26, Spearman’s ρ = 0.52, p = .006).
Conclusion This study indicates that there are two factors behind the brain neuroimaging findings in spontaneous intracranial hypotension: Cerebral venous dilation and brain descent. Certain brain neuroimaging signs correlate with spinal cerebrospinal fluid leakage severity, depending on different circumstances.
PMID: 30301380
DOI: 10.1177/0333102418804161

Takai K, Niimura M, Hongo H, Umekawa M, Teranishi A, Kayahara T, Taniguchi M.
World Neurosurg. 2018 Oct 4. pii: S1878-8750(18)32248-4. doi: 10.1016/j.wneu.2018.09.193. [Epub ahead of print]
Abstract
OBJECTIVE:
The diagnosis and treatment of intracranial hypotension associated with a spinal cerebrospinal fluid (CSF) leak, especially in comatose patients, have yet to be established.
METHODS:
Clinical manifestations, neuroimaging findings, and treatment outcomes in 11 patients (Glasgow Coma Scale 10±4) were described and compared with 36 patients with normal consciousness.
RESULTS:
Patients with disturbed consciousness were diagnosed at a significantly older age (55±11 years; p<0.001) than those without (42±8.8 years). Neuroimaging findings in patients with disturbed consciousness were characterized by a smaller midbrain-pons angle (7.8±10°; p<0.001), brainstem swelling (122%; p=0.002), and thicker subdural hematomas (16±7.0 mm; p<0.001). Epidural blood patch (EBP) alone did not achieve sustained improvements in patients with disturbed consciousness, but did in most patients without (94%; p=0.001). Over the treatment course, 5 patients progressed to coma, which correlated with a high signal intensity on T2-weighted MRI in the brainstem. Hematoma drainage before EBP caused neurological deterioration in 2 patients. Simultaneous EBP following hematoma drainage achieved sustained improvements in 5 out of 6 patients. Simultaneous microsurgical dural repair following hematoma drainage achieved more rapid improvements in 3 out of 3 patients.
CONCLUSIONS:
Among patients with intracranial hypotension due to a spinal CSF leak, disturbed consciousness may occur in elderly patients because of severe diencephalic-mesencephalic deformities. Simultaneous EBP following safe hematoma drainage is indicated for these patients. Alternatively, dural repair is indicated for patients for whom the spinal level of dural pathology has been identified. Hematoma drainage before EBP is not recommended because it caused deterioration.
PMID: 30292664
DOI: 10.1016/j.wneu.2018.09.193

Lee JY, Lee MJ, Park HJ, Park JH, Jeong HJ, Oh MS, Son YH, Sim WS.
Br J Neurosurg. 2018 Oct 3:1-3. doi: 10.1080/02688697.2018.1519109. [Epub ahead of print]
Abstract
BACKGROUND:
Epidural blood patch (EBP) has been shown to be an effective treatment option for spontaneous intracranial hypotension(SIH). We investigated whether response to the EBP was related to the distance of the injection site from the leakage site in patients with SIH.
METHODS:
We reviewed patients with SIH who underwent EBP at a single hospital. Patients were assigned to group R (response after EBP) or group N (no response after EBP). We then analyzed the demographics, clinical characteristics, leakage site, leakage length, EBP injection level and distance from leakage site, and injected EBP volume.
RESULTS:
Sixty-two patients were included in the analysis. The overall response rate to EBP was 59.7% (37 patients). The leakage length and injection distance from the leakage site did not differ between the two groups. Age, gender, body mass index, leakage site, and EBP volume did not differ significantly between the two groups.
CONCLUSION:
The clinical effect of EBP in SIH was not affected by leakage length or injection distance to leakage site. Further large studies must be conducted to investigate the efficacy of targeted EBP for SIH.
PMID: 30282491
DOI: 10.1080/02688697.2018.1519109

Montenegro MM, Cutsforth-Gregory JK
Headache. 2018 Sep;58(8):1238-1243. doi: 10.1111/head.13346. Epub 2018 Jun 19.
Abstract
OBJECTIVE:
To review the clinical and radiographic characteristics of orthostatic headache following suboccipital craniectomy without CSF leak after encountering 2 such patients.
BACKGROUND:
Orthostatic headache may occur without CSF leak, suggesting alternative mechanisms for postural head pain in some patients.
METHODS:
Patients who were referred for orthostatic headache and suspected CSF leak within 1 year after suboccipital craniectomy but who had negative post-operative head and spine MRI, normal radioisotope cisternography, and normal or elevated CSF opening pressure were identified and their medical records reviewed.
RESULTS:
Two patients satisfied all inclusion criteria. One underwent suboccipital craniectomy for treatment of Chiari malformation type I in adolescence; the same surgical approach was used to resect a posterior fossa meningioma in the second. Both patients had non-orthostatic headache before surgery and newly developed orthostatic headache later. Delay from surgery to orthostatic headache onset was variable (2-9 months). Headaches were predominantly occipital and pressure-like, worsened by upright posture, bending forward, and exertion. MRI consistently showed adequate decompression of the posterior fossa. Epidural blood patches were unhelpful in the one patient in whom they were performed.
CONCLUSIONS:
Orthostatic headaches may develop after suboccipital craniectomy in the absence of CSF leak. Possible mechanisms include (1) scarring of the dura in the posterior fossa that leads to compensatory increased distensibility of lumbar dura and (2) sensitization of mechanosensitive dural nociceptors from altered skull-dura apposition.
PMID: 29920678
DOI: 10.1111/head.13346

Zhang D, Wang J, Zhang Q, He F, Hu X.
Headache. 2018 Sep;58(8):1244-1255. doi: 10.1111/head.13413. Epub 2018 Sep 20.
Abstract
OBJECTIVE:
Spontaneous intracranial hypotension is a risk factor for cerebral venous thrombosis. The occurrence of cerebral venous thrombosis in patients with spontaneous intracranial hypotension raises difficult practical questions regarding the management of the 2 conditions. We reviewed our experience and the relevant literature to evaluate these related questions.
METHODS:
We retrospectively studied the medical records and imaging studies of patients with spontaneous intracranial hypotension at a tertiary center from January 2007 through January 2017. The main search strategy was a literature review of journal articles in PubMed (1966 to January 2017).
RESULTS:
Among 374 patients with spontaneous intracranial hypotension, 4 were also diagnosed with cerebral venous thrombosis. A literature review yielded an additional 31 cases, including 21 men and 14 women with a mean age of 40.6 years. Of the 35 patients, 8 (22.8%) patients received anticoagulation therapy and epidural blood patch. Nineteen (54.3%) patients were given anticoagulant only. Seven (20%) patients were treated with epidural blood patch only. One (2.9%) patient did not receive epidural blood patch or anticoagulation therapy. There is no difference in terms of age, sex, diagnosis interval, association with other complications, and prognosis between the first 3 groups. Of the 19 patients who received anticoagulation therapy, 4 patients (21.1%) had intracranial hemorrhage or hematoma enlargement after anticoagulation, and one of these 4 patients died following further intracranial hemorrhage. Of the 8 patients who received both anticoagulation and epidural blood patch, 1 patient (12.5%, P = 0.528) developed subdural hematoma after anticoagulation. Of the 5 cases had intracranial hemorrhage aggravation after anticoagulation, 4 were subdural hematoma occurrence or enlargement.
CONCLUSION:
Cerebral venous thrombosis is a rare but important complication of spontaneous intracranial hypotension. The primary focus of treatment should be the treatment of intracranial hypotension. It could be possible that anticoagulation might increase the risk of intracranial hemorrhage in patients with spontaneous intracranial hypotension, although a firm conclusion could not be drawn based on the limited number of patients currently available. The use of anticoagulation therapy should be prudent and should be monitored carefully if initiated.
PMID: 30238694
DOI: 10.1111/head.13413

Naveed MA, Mangla R, Idrees H, Mehta RI.
Case Rep Neurol Med. 2018 Sep 16;2018:5870584. doi: 10.1155/2018/5870584. eCollection 2018.
Abstract
We report the case of a 51-year-old man with no significant past medical history, who underwent elective revision spinal surgery and subsequently developed intracranial hypotension, remote cerebellar haemorrhage (RCH), and mild hydrocephalus on the fourth postoperative day. Remote cerebellar haemorrhage is a known complication of supratentorial surgery. This iatrogenic phenomenon may also occur following spinal surgery, due to dural tearing and rapid cerebral spinal fluid (CSF) leakage, resulting in intracranial hypotension and cerebellar haemorrhage. This complication may result in severe permanent neurologic sequelae; hence, it is of pertinence to diagnose and manage it rapidly in order to optimise patient outcome.
PMID: 30305969
PMCID: PMC6165595
DOI: 10.1155/2018/5870584

Tomas Dobrocky, Pascal J. Mosimann, Felix Zibold, Pasquale Mordasini, Andreas Raabe, Christian T. Ulrich, Jan Gralla, Jürgen Beck, Eike I. Piechowiak
Radiology 2018 Sep 18 ePub online
Abstract
Purpose
To propose a modified dynamic CT myelographic technique to locate cerebrospinal fluid (CSF) leaks, also known as cryptogenic leaks, in patients with spontaneous intracranial hypotension (SIH) in whom previous imaging did not show the dural breach.
Materials and Methods
This retrospective analysis included 74 consecutive patients with SIH and a myelographically proven CSF leak who were evaluated between February 2013 and October 2017. In 14 patients, dynamic CT myelography in the prone or lateral position showed the exact leakage point after unsuccessful previous imaging. During image analysis, the first time point showing extrathecal contrast material was defined as the site of dural breach point.
Results
Mean population age was 44 years (range, 25–65 years [nine women; mean age, 44 years; age range, 25–65 years] [five men; mean age, 46 years; age range, 29–61 years]). All patients had previously undergone spine MRI, conventional dynamic myelography, and CT myelography. Subsequent dynamic CT myelography covered a mean range of seven vertebral levels. The leak was caused by a calcified microspur in 10 patients and by a dural tear at the axilla of a spinal nerve root in the remaining four. The mean volume CT dose index of dynamic CT myelography was 107 mGy (range, 12–246 mGy), and the mean dose-length product was 1347 mGy·cm (range, 550–3750 mGy·cm).
Conclusion
Dynamic CT myelography is a valuable adjunctive tool with which to identify the precise location of a dural tear when other examinations are unsuccessful.
PMID: 30226459
DOI: 10.1148/radiol.2018180732

Fujiwara M, Moriyama E, Araki T.
Intern Med. 2018 Sep 12. doi: 10.2169/internalmedicine.1136-18. [Epub ahead of print]
No abstract available
PMID: 30210113
Full text
DOI: 10.2169/internalmedicine.1136-18

Lee MS, Lee S, Seo DK, Yoon SH, Choi SS.
J Dent Anesth Pain Med. 2018 Aug;18(4):255-259. doi: 10.17245/jdapm.2018.18.4.255. Epub 2018 Aug 28.
Abstract
Sudden headache onset may rarely be caused by spontaneous intracranial hypotension (SIH). Other associated symptoms in patients with SIH are nausea, vomiting, vertigo, hearing alteration, and visual disturbance. This case report describes a 43-year-old female diagnosed with SIH who developed diplopia after resolution of an abrupt-onset headache, which was managed with conservative treatments, including bed rest and hydration. She was also diagnosed with secondary right sixth cranial nerve palsy. Although conservative management relieved her headache, the diplopia was not fully relieved. Application of an autologous epidural blood patch successfully relieved her diplopia, even after 14 days from the onset of visual impairment.
PMID: 30186972
PMCID: PMC6115369
DOI: 10.17245/jdapm.2018.18.4.255

Ozyigit A, Michaelides C, Natsiopoulos K.
Front Neurol. 2018 Aug 17;9:673. doi: 10.3389/fneur.2018.00673. eCollection 2018.
Abstract
Spontaneous intracranial hypotension (SIH) is a rare and often underdiagnosed condition, which commonly results from a cerebrospinal fluid leak. The classic clinical presentation of SIH is a postural headache and dizziness. Less frequent complications include nausea, neck stiffness, and even coma. This case report describes a 70-year-old woman with an initial complaint of postural headaches and sleep attacks, who developed a 22-month progressive history of personality and behavioral changes, cognitive decline, urinary incontinence, chorea, and dysarthria. Although no specific cerebrospinal fluid leak was identified, the patient was suspected of having SIH and her symptoms completely reversed after a 2-month course of steroids. This case highlights that SIH represents a rare and reversible cause of a wide spectrum of neurological symptoms, including dementia. Neurologists should be aware of this diagnosis when evaluating patients with neurological signs and symptoms that cannot otherwise be explained.
PMID: 30174645
PMCID: PMC6107704
DOI: 10.3389/fneur.2018.00673

Friedman DI.
Continuum (Minneap Minn). 2018 Aug;24(4, Headache):1066-1091. doi: 10.1212/CON.0000000000000623.
PURPOSE OF REVIEW:
Headache disorders attributed to low and high intracranial pressure are commonly encountered in specialty headache practices and may occur more frequently than realized. While the headaches resulting from intracranial pressure disorders have what are conventionally thought of as defining characteristics, a substantial minority of patients do not manifest the “typical” features. Moreover, patients with intracranial pressure disorders may also have a preexisting primary headache disorder. Heightening the complexity of the presentation, the headaches of intracranial pressure disorders can resemble the phenotype of a primary disorder. Lastly, patients with so-called intracranial “hypotension” often have normal CSF pressure and neuroimaging studies. Thus, a high index of suspicion is needed. The published literature has inherent bias as many types of specialists evaluate and treat these conditions. This article reviews the key points to emphasize the history, examination, and laboratory evaluation of patients with intracranial pressure disorders from a neurologist’s perspective.
RECENT FINDINGS:
Lumbar puncture opening pressure in patients with spontaneous intracranial hypotension was low enough to meet diagnostic criteria (≤60 mm CSF) in only 34% of patients in one study. Most patients had an opening pressure in the low normal to normal range, and 5% had an opening pressure of 200 mm CSF or more. Diskogenic microspurs are a common cause of this syndrome. The Idiopathic Intracranial Hypertension Treatment Trial found that most participants had a headache phenotype resembling migraine or tension-type headache. No “typical” or characteristic headache phenotype was found, and headache-related disability was severe at baseline. Headache disability did not correlate with the lumbar puncture opening pressure at baseline or at the 6-month primary outcome period. Although participants who were randomly assigned to acetazolamide had a lower mean CSF opening pressure at 6 months, headache disability in that group was similar to the group who received placebo.
SUMMARY:
Significant overlap is seen in the symptoms of high and low CSF pressure disorders and in those of primary headache disorders. Neurologists are frequently challenged by patients with headaches who lack the typical clinical signs or imaging features of the pseudotumor cerebri syndrome or spontaneous intracranial hypotension. Even when characteristic symptoms and signs are initially present, the typical features of both syndromes tend to lessen or resolve over time; consider these diagnoses in patients with long-standing “chronic migraine” who do not improve with conventional headache treatment. While the diagnostic criteria for pseudotumor cerebri syndrome accurately identify most patients with the disorder, at least 25% of patients with spontaneous intracranial hypotension have normal imaging and over half have a normal lumbar puncture opening pressure. Detailed history taking will often give clues that suggest a CSF pressure disorder. That said, misdiagnosis can lead to significant patient morbidity and inappropriate therapy.
PMID: 30074550
DOI: 10.1212/CON.0000000000000623

Beck J, Raabe A, Schievink WI, Fung C, Gralla J, Piechowiak E, Seidel K, Ulrich CT.
Neurosurgery. 2018 Jul 25. doi: 10.1093/neuros/nyy312. [Epub ahead of print]
Abstract
BACKGROUND:
Spinal cerebrospinal fluid (CSF) leaks are the cause of spontaneous intracranial hypotension (SIH).
OBJECTIVE:
To propose a surgical strategy, stratified according to anatomic location of the leak, for sealing all CSF leaks around the 360° circumference of the dura through a single tailored posterior approach.
METHODS:
All consecutive SIH patients undergoing spinal surgery were included. The anatomic site of the leak was exactly localized. We used a tailored hemilaminotomy and intraoperative neurophysiological monitoring (IOM) for all cases. Neurological status was assessed before and up to 90 d after surgery.
RESULTS:
Forty-seven SIH patients had an identified CSF leak between the levels C6 and L1. Leaks, anterior to the spinal cord, were approached by a transdural trajectory (n = 28). Leaks lateral to the spinal cord by a direct extradural trajectory (n = 17) and foraminal leaks by a foraminal microsurgical trajectory (n = 2). The transdural trajectory necessitated cutting the dentate ligament accompanied by elevation and rotation of the spinal cord under continuous neuromonitoring (spinal cord release maneuver, SCRM). Four patients had transient defiticts, none had permanent neurological deficits. We propose an anatomic classification of CSF leaks into I ventral (77%, anterior dural sac), II lateral (19%, including nerve root exit, lateral, and dorsal dural sac), and III foraminal (4%).
CONCLUSION:
Safe sealing (with IOM) of all CSF leaks around the 360° surface of the dura is feasible through a single posterior approach. The exact surgical trajectory is selected according to the anatomic category of the leak.
PMID: 30053151
DOI: 10.1093/neuros/nyy312

Xia P, Zhang SR, Zhou ZJ, Shao YQ, Hu XY.
Neurol Res. 2018 Jul 27:1-6. doi: 10.1080/01616412.2018.1495883. [Epub ahead of print]
Abstract
OBJECTIVES:
To assess the prevalence and related factors of benign paroxysmal positional vertigo (BPPV) in patients with spontaneous intracranial hypotension (SIH).
METHODS:
We retrospectively reviewed 156 consecutive inpatients with SIH, and collected the clinical and radiological data. These patients were divided into BPPV group and non-BPPV group according to the clinical manifestation and the results of Dix-Hallpike or supine roll tests during hospitalization period. We performed a univariate analysis and a further multiple logistic regression analysis to identify the related factors of the development of BPPV in SIH patients.
RESULTS:
BPPV was detected in 18 patients among the total 156 SIH patients (11.54%). The univariate analysis showed a low cerebrospinal fluid (CSF) pressure (P = 0.018), a small pontomesencephalic angle (P = 0.012) and a positive venous distension sign (VDS) (P = 0.045) were associated with the presence of BPPV. But the multivariate analysis only demonstrated a low CSF pressure was related to the presence of BPPV (OR = 1.022, 95% CI: 1.001-1.043, P = 0.044).
CONCLUSION:
BPPV is common in SIH patients. SIH patients with low CSF pressure may be prone to develop BPPV.
PMID: 30052143
DOI: 10.1080/01616412.2018.1495883

Takai K, Taniguchi M.
World Neurosurg. 2018 Jul 25. pii: S1878-8750(18)31626-7. doi: 10.1016/j.wneu.2018.07.148. [Epub ahead of print]
Abstract
BACKGROUND:
Difficulties are associated with the diagnosis and management of patients with coma due to intracranial hypotension.
CASE DESCRIPTION:
The authors describe the case of a 70-year-old male with coma (Glasgow Coma Scale of 6) with fixed dilated pupils due to severe intracranial hypotension. After unsuccessful epidural blood patch (EBP), the patient underwent microsurgical dural repair and drainage of hematoma with intracranial pressure (ICP) monitoring. Intraoperatively, a dural tear associated with a CSF leak was identified at the thoracolumbar junction ventral to the spinal cord. The dural tear was repaired using posterior laminoplasty with a transdural approach without spinal fixation. Immediately after surgery, ICP was low, but recovered to a physiological range in 4 hours. Consciousness level favorably improved in a week and the patient has remained stable for 1.5 years with good quality of life without recurrence.
CONCLUSIONS:
The patient in this report represents the first described case of intracranial hypotension with coma due to a CSF leak caused by a spinal ventral dural tear. In the setting of failed EBP attempt, our technique may be a treatment option for severe intracranial hypotension.
PMID: 30055363
DOI: 10.1016/j.wneu.2018.07.148

Sasikumar S, Lizarraga KJ, Gnanamanogaran B, Voisin MR, Peng P, Fasano A.
Neurology. 2018 Jul 6. pii: 10.1212/WNL.0000000000005953. doi: 10.1212/WNL.0000000000005953. [Epub ahead of print]
No abstract available.
PMID: 29980638
DOI: 10.1212/WNL.0000000000005953

Qureshi AI, Kherani D, Waqas MA, Qureshi MH, Raja FM, Wallery SS.
Brain Behav. 2018 Jul;8(7):e01026. doi: 10.1002/brb3.1026. Epub 2018 Jun 19.
Abstract
BACKGROUND:
We performed a prospective study to quantify changes in various aspects of upright posture intolerance in patients with intracranial hypotension.
METHODS:
Six patients were provided a standard questionnaire before, immediately after epidural blood patch injection and at follow-up visit within 1 month after epidural blood injection inquiring: (a) How long can they stand straight without any support? (b) Do they feel any sense of sickness when they sit or lie down after standing? (c) How long do they have to wait before they are comfortable standing again after they have stood straight? (d) How effectively and fast can they get up from sitting or lying position to stand straight? and (e) Rate their activities in upright posture without support on a standard vertical visual analogue scale between 100 (can do everything) and 0 (cannot do anything).
RESULTS:
All patients responded that they could not stand straight for ≥30 min (four responding <5 min) on pretreatment evaluation. All patients reported improvement in this measure immediately post-procedure with two reporting ≥30 min. At follow-up, three patients reported further improvement and one patient reported worsening in this measure. The magnitude of improvement ranged from 10 to 80 points increase immediately post-procedure in their ability to perform activities, while they are standing without any support on visual analogue scale. At follow-up, four patient reported additional improvement in their ability to perform activities, while they are standing without any support (ranged from 10 to 20 points increase compared with immediately post-procedure rating).
CONCLUSIONS:
We present semiquantitative data on various aspects of upright posture intolerance in patients with intracranial hypotension before and after epidural blood injection.
PMID: 29920982
DOI: 10.1002/brb3.1026
Free full text

Perry A, Graffeo CS, Brinjikji W, Copeland WR 3rd, Rabinstein AA, Link MJ1.
J Neurosurg Spine. 2018 Jun;28(6):669-678. doi: 10.3171/2017.10.SPINE17806. Epub 2018 Mar 30.
Abstract
Spontaneous intracranial hypotension (SIH) is an uncommon headache etiology, typically attributable to an unprovoked occult spinal CSF leak. Although frequently benign, serious complications may occur, including cerebral venous thrombosis (CVT). The objective of this study was to examine a highly complicated case of CVT attributable to SIH as a lens for understanding the heterogeneous literature on this rare complication, and to provide useful, evidence-based, preliminary clinical recommendations. A 43-year-old man presented with 1 week of headache, dizziness, and nausea, which precipitously evolved to hemiplegia. CT venography confirmed CVT, and therapeutic heparin was initiated. He suffered a generalized seizure due to left parietal hemorrhage, which subsequently expanded. He developed signs of mass effect and herniation, heparin was discontinued, and he was taken to the operating room for clot evacuation and external ventricular drain placement. Intraoperatively, the dura was deflated, suggesting underlying SIH. Ventral T-1 CSF leak was identified, which failed multiple epidural blood patches and required primary repair. The patient ultimately made a complete recovery. Systematic review identified 29 publications describing 36 cases of SIH-associated CVT. Among 31 patients for whom long-term neurological outcome was reported, 25 (81%) recovered completely. Underlying coagulopathy/risk factors were identified in 11 patients (31%). CVT is a rare and potentially lethal sequela occurring in 2% of SIH cases. Awareness of the condition is poor, risking morbid complications. Evaluation and treatment should be directed toward identification and treatment of occult CSF leaks. Encouragingly, good neurological outcomes can be achieved through vigilant multidisciplinary neurosurgical and neurocritical care.
PMID: 29600909
DOI: 10.3171/2017.10.SPINE17806

He FF, Li L, Liu MJ, Zhong TD, Zhang QW, Fang XM.
J Neurol Surg B Skull Base. 2018 Jun;79(3):217-223. doi: 10.1055/s-0037-1606312. Epub 2017 Sep 11.
Abstract
Objective  An epidural blood patch (EBP) is the mainstay of treatment for refractory spontaneous intracranial hypotension (SIH). We evaluated the treatment efficacy of targeted EBP in refractory SIH.
Methods  All patients underwent brain magnetic resonance imaging (MRI) with contrast and heavily T2-weighted spine MRI. Whole spine computed tomography (CT) myelography with non-ionic contrast was performed in 46 patients, and whole spine MR myelography with intrathecal gadolinium was performed in 119 patients. Targeted EBPs were placed in the prone position one or two vertebral levels below the cerebrospinal fluid (CSF) leaks. Repeat EBPs were offered at 1-week intervals to patients with persistent symptoms, continued CSF leakage, or with multiple leakage sites.
Results  Brain MRIs showed pachymeningeal enhancement in 127 patients and subdural hematomas in 32 patients. One hundred fifty-two patients had CSF leakages on heavily T2-weighted spine MRIs. CSF leaks were also detected on CT and MR myelography in 43 and 111 patients, respectively. Good recovery was achieved in all patients after targeted EBP. No serious complications occurred in patients treated with targeted EBP during the 1 to 7 years of follow-up.
Conclusions  Targeted and repeat EBPs are rational choices for treatment of refractory SIH caused by CSF leakage.
PMID: 29765818
PMCID: PMC5951701 [Available on 2019-06-01]
DOI: 10.1055/s-0037-1606312

Ohtonari T, Ota S, Himeno T, Nishihara N, Sato M, Tanaka A.
World Neurosurg. 2018 Jun 29. pii: S1878-8750(18)31387-1. doi:10.1016/j.wneu.2018.06.171. [Epub ahead of print]
OBJECTIVE: The effects of large-volume epidural blood patch (EBP) remain unclear in cerebrospinal fluid (CSF) leak patients. We report excellent outcomes from 15 consecutive CSF leak cases that underwent large-volume EBPs using an intravenous catheter from single lumbar entry point, together with outcomes from 4 patients who underwent direct surgical closure or drip-and-rest therapy at the same period.
METHODS: Nineteen patients with idiopathic CSF leaks were enrolled in this study, since November 2011 (12 female; age: 43.3 ± 14.0 years). Patient demographic data, radiological findings, symptoms, administrated therapies, complications, and clinical courses were investigated retrospectively.
RESULTS: Different types of headache were observed, including: typical orthostatic headache alone, 10 cases; orthostatic headache with chronic subdural hematoma (CSDH), 3 cases; and posture-unrelated headache accompanied with CSDH, 6 cases. Regarding treatments, in one case, direct surgical closure was performed. In 15 cases, large-volume EBPs were performed, and the volume of injected blood was 44.8 ± 21.6 mL. The other 3 cases were treated by simple drip infusion regardless of the drainage for CSDH. Out of 9 cases with accompanied CSDH, recurrence of subdural hematoma was completely prevented by the application of EBP after drainage in 5 cases and without drainage in 3, and by simple intravenous drip-and-rest after drainage in 1. Among 10 patients suffering from typical orthostatic headache alone, symptoms disappeared completely in 7 cases and were relieved in 3.
CONCLUSIONS: We demonstrate here a perfect control of spinal CSF leaks with the administration of large-volume EBP through an intravenous catheter.
PMID: 29966793
DOI: 10.1016/j.wneu.2018.06.171

Fujii N, Fujii H, Fujita A, Kim Y, Sugimoto H.
Radiol Case Rep. 2018 Jun 20;13(4):834-838. doi: 10.1016/j.radcr.2018.05.014. eCollection 2018 Aug.
Abstract
Spontaneous intracranial hypotension (SIH) is a well-known cause of orthostatic headache. Although subdural fluid collection is a usual complication of SIH, SIH as a risk factor for cerebral venous thrombosis (CVT) is not well-known. There are several mechanisms that could contribute to the development of CVT in SIH. Herein, we report a case of a 33-year-old woman with SIH complicated by CVT. She was treated with anticoagulation but did not receive a blood patch for the SIH, because there was resolution of orthostatic headache with bed rest and sufficient hydration. Follow-up magnetic resonance imaging showed resolution of the findings of SIH and CVT. Patients with SIH should be closely observed for any change in the headache pattern, which might suggest the development of CVT.
KEYWORDS:
Cerebral venous thrombosis; Spontaneous intracranial hypotension
PMID: 29955241
PMCID: PMC6020096
DOI: 10.1016/j.radcr.2018.05.014

Rath S, Shaikh A, Narwal P, Gupta A.
BMJ Case Rep. 2018 Jun 4;2018. pii: bcr-2018-224240. doi: 10.1136/bcr-2018-224240.
Abstract
We describe the case of a 54-year-old man who presented with new-onset positional headaches and seizures, which were determined to be secondary to spontaneous intracranial hypotension due to a cervicothoracic spinal cerebrospinal fluid leak, and its associated complications.
PMID: 29866680
DOI: 10.1136/bcr-2018-224240

Peter G. Kranz, MD; Linda Gray, MD; Timothy J. Amrhein, MD
Headache 2018. First published: 24 May 2018
Abstract
Objective
To discuss common myths and misperceptions about spontaneous intracranial hypotension (SIH), focusing on common issues related to diagnosis and treatment, and to review the evidence that contradicts and clarifies these myths.
Background
Recognition of SIH has increased in recent years. With increasing recognition, however, has come an increased demand for management by neurologists and headache specialists, some of whom have little prior experience with the condition. This dearth of practical experience, and lack of awareness of recent investigations into SIH, produces heterogeneity in diagnostic and treatment pathways, driven in part by outdated, confusing, or unsubstantiated conceptions of the condition. We sought to address this heterogeneity by identifying 10 myths and misperceptions that we frequently encounter when receiving referrals for suspected or confirmed SIH, and to review the literature addressing these topics.
Methods
Ten topics relevant to diagnosis and treatment SIH were generated by the authors. A search for studies addressing SIH was conducted using PubMed and EMBASE, limited to English language only, peer reviewed publications from inception to 2018. Individual case reports were excluded. The resulting studies were reviewed for relevance to the topics in question.
Results
The search generated 557 studies addressing SIH; 75 case reports were excluded. Fifty‐four studies were considered to be of high relevance to the topics addressed, and were included in the data synthesis. The topics are presented in the form of a narrative review.
Conclusions
The understanding of SIH has evolved over the recent decades, leading to improvements in knowledge about the pathophysiology of the condition, diagnostic strategies, and expanded treatments. Awareness of these changes, and dispelling outdated misconceptions about SIH, is critical to providing appropriate care for patients and guiding future investigations going forward.
PMID: 29797515
DOI: 10.1111/head.13328
https://doi.org/10.1111/head.13328

Dickinson J, Kroll D, Bentley J, Gustin AJ.
Cureus. 2018 Apr 9;10(4):e2454. doi: 10.7759/cureus.2454.
Abstract
Pseudohypoxic brain swelling (or the more recent term, postoperative intracranial hypotension-associated venous congestion) is a rare and potentially deadly complication that can occur after routine spine or brain surgery. The mechanism of this injury has been described as a rapid cerebral spinal fluid drainage leading to venous cerebral congestion. The clinical and radiographic findings mimic those found in a patient who has suffered an anoxic brain injury. We present the third reported case of postoperative intracranial hypotension-associated venous congestion following spinal surgery.
PMID: 29888158
PMCID: PMC5991919
DOI: 10.7759/cureus.2454

Bhimani R, Bhimani F, Singh P.
Case Rep Med. 2018 Apr 2;2018:5061898. doi: 10.1155/2018/5061898. eCollection 2018.
Abstract
INTRODUCTION:
Intracranial hypotension may occur when CSF leaks from the subarachnoid space. Formation of intracranial, subdural, and subarachnoid hemorrhage has been observed after significant CSF leak as seen in lumbar puncture or ventricular shunt placement. However, very few cases, referring to these remote complications following spine surgery, have been described in literature. We present a case of a 10-year-old male child operated for idiopathic scoliosis with low-lying conus medullaris who postoperatively developed subdural hemorrhage.
CASE REPORT:
A case of a 10-year-old male operated for idiopathic scoliosis with low-lying conus medullaris is presented. To correct this, detethering was done at the L3 level, laminectomy was done from L2 to L3 with pedicular screw fixation from T3 to L2, and bone grafting with right costoplasty was done from the 3rd to the 6th ribs. On the 5th day postoperatively, the patient developed convulsions and drowsiness and recovered subsequently by postoperative day 7.
CONCLUSION:
We report a rare case of an acute intracranial subdural hemorrhage caused by intracranial hypotension following scoliosis and detethering of cord surgery. This report highlights the potential morbidity associated with CSF leak occurring after this surgery.
PMID: 29808094
PMCID: PMC5902091
DOI: 10.1155/2018/5061898

Schievink WI, Maya MM, Moser FG, Jean-Pierre S, Nuño M.
Neurology. 2018 Apr 13. pii: 10.1212/WNL.0000000000005477. doi: 10.1212/WNL.0000000000005477. [Epub ahead of print]
Abstract
OBJECTIVE:
To review our experience with patients with spontaneous intracranial hypotension (SIH) and coma because, although disorders of consciousness may complicate SIH, no comprehensive study of such patients has been reported.
METHODS:
Using a prospectively maintained registry, we identified all patients with SIH in whom coma developed. Patients or their caregivers/families were contacted for follow-up. Patients were compared to a cohort of patients with SIH without coma.
RESULTS:
The mean age of the 12 men and 3 women with SIH was 56.2 years (range 34-72 years) at the time of onset of coma. In one-third of patients, coma developed after craniotomy for subdural hematomas or for an unrelated intracranial pathology. Imaging showed brain sagging, including bilateral temporal lobe herniation, in all 15 patients and brainstem edema in 8 patients (53%). Overall, coma was reversible in 7 of 15 patients treated with epidural blood patches, in 2 of 4 treated with percutaneous glue injections, and in 6 of 6 treated surgically. Only 1 patient had residual neurologic deficit related to coma (Glasgow Outcome Scale score 4 [moderate disability]). Compared to patients with SIH without coma (n = 568), those with coma were older, more often were male, and more often underwent surgery.
CONCLUSIONS:
Coma in SIH is rare, reversible, and invariably associated with brain sagging. Coma due to SIH may be refractory to the usual percutaneous procedures, and surgical closure of the CSF leak may be required to regain consciousness.
PMID: 29653986
DOI: 10.1212/WNL.0000000000005477

Young SJ, Quisling RG, Bidari S, Sanghvi TS.
Radiol Res Pract. 2018 Mar 11;2018:6862739. doi: 10.1155/2018/6862739. eCollection 2018.
Abstract
PURPOSE:
Intracranial hypotension (IH) often remains undetected using current MR diagnostic criteria. This project aims to demonstrate that central incisural herniation is highly effective in helping to make this diagnosis.
MATERIALS AND METHODS:
Magnetic resonance imaging (MRI) was analyzed in 200 normal and 81 clinically known IH patients. MRI reference lines approximating the plane of the incisura, the plane of the diaphragma sella, the plane of the foramen magnum, and the plane of the visual pathway were utilized to measure the position of selected brain structures relative to these reference lines.
RESULTS:
All IH patients had highly statistically significant (p < 0.0001) measurable evidence of downward central incisural herniation when compared to normal controls. The first of the important observations was a downward shift of the mammillary bodies, which shortened the midsagittal width of the interpeduncular fossa cistern. A concurrent downward shift and deformity of the tuber cinereum accompanied the mammillary body shift. The second essential observation was an abnormal clockwise rotation of the long axis of the visual pathway. A severity grading system is proposed based on the extent of these shifts as well as secondary shifts of the brain stem, splenium, and cerebellar tonsils.
CONCLUSION:
This study objectively delineates the anatomic shifts of brain structures adjacent to the incisura and foramen magnum. This methodology is sufficient to recognize the features of IH and to stratify the spectrum of IH findings into a functional grading system for quantifying the results of interventional therapy.
PMID: 29713529
PMCID: PMC5866870
DOI: 10.1155/2018/6862739

Robles LA, Cuevas-Solórzano A.
World Neurosurg. 2018 Mar;111:99-108. doi: 10.1016/j.wneu.2017.12.061. Epub 2017 Dec 18.
Abstract
BACKGROUND:
Although cranioplasty is a common procedure, it may cause a variety of complications. Massive brain swelling after cranioplasty (MBSC) is an unusual complication that has been reported more frequently in recent years. Most of the existing information about this condition is speculative and the cause remains unclear.
METHODS:
A PubMed and Scopus search adhering to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed to include studies reporting patients with MBSC. Different information was analyzed in these cases to describe the characteristics and identify risk factors for MBSC.
RESULTS:
The search yielded 19 articles with a total of 26 patients. All studies were case reports and small case series. In most patients, preoperative intracranial hypotension and a considerable degree of sinking of skin flap were identified; this was the only constant finding observed in these cases. In addition, we propose a grading system to estimate the degree of preoperative sinking of skin flap and an algorithm with recommendations to decrease the incidence of MBSC.
CONCLUSIONS:
MBSC is an unusual, highly lethal, and probably underreported condition. The information gathered in this review indicates that MBSC occurs secondary to a cascade of pathologic events triggered by the bone flap implantation. This evidence suggests that the primary pathologic change is a sudden increase in the intracranial pressure acting on a brain chronically exposed to intracranial hypotension.
PMID: 29269069
DOI: 10.1016/j.wneu.2017.12.061

Schievink WI, Maya MM, Barnard ZR, Moser FG, Jean-Pierre S, Waxman AD, Nuño M.
Oper Neurosurg (Hagerstown). 2018 Mar 8. doi: 10.1093/ons/opy029. [Epub ahead of print]
Abstract
BACKGROUND:
Behavioral variant frontotemporal dementia (bvFTD) is a devastating early onset dementia. Symptoms of bvFTD may be caused by spontaneous intracranial hypotension (SIH), a treatable disorder, but no comprehensive study of such patients has been reported.
OBJECTIVE:
To describe detailed characteristics of a large cohort of patients with SIH and symptoms of bvFTD.
METHODS:
We identified patients with SIH who met clinical criteria for bvFTD. Patients were compared to a cohort of SIH patients without bvFTD.
RESULTS:
The mean age for the 21 men and 8 women was 52.9 yr (range, 37-65 yr). All 29 patients with bvFTD symptoms had hypersomnolence. Magnetic resonance imaging showed brain sagging in all patients, cerebrospinal fluid (CSF) opening pressure low in about half of patients, but a spinal CSF leak could not be detected in any patient. All patients underwent epidural blood patching, but 26 patients eventually underwent 1 or more surgical procedures. Overall, a good outcome was obtained in 21 patients (72%); 20 (91%) of 22 patients who had not undergone prior Chiari surgery compared to 1 (14%) of 7 patients who did undergo Chiari surgery (P < .003). Compared to SIH patients without symptoms of bvFTD (n = 547), those with bvFTD symptoms were older, more often male, less often demonstrated CSF leak on spinal imaging, and more often underwent surgery (P < .02).
CONCLUSION:
bvFTD in SIH is rare and associated with brain sagging and hypersomnolence. Spinal CSF leaks are rarely detected. bvFTD symptoms are often refractory to the usual percutaneous procedures but most patients can be cured.
PMID: 29534203
DOI: 10.1093/ons/opy029

Fredrickson VL, Patel A, Pham MH, Strickland BA, Ohiorhenuan I, Chen T.
World Neurosurg. 2018 Mar;111:68-72. doi: 10.1016/j.wneu.2017.12.027. Epub 2017 Dec 14.
Abstract
BACKGROUND:
Overshunting of cerebrospinal fluid may lead to intracranial hypotension and dilation of spinal epidural veins. Radiculopathy may rarely occur secondary to engorged spinal epidural veins. In addition, the cause of radiculopathy may be obscured by concomitant spinal degenerative changes. We present a case and review the pathogenesis as well as the current clinical literature.
CASE DESCRIPTION:
A 29-year-old woman presented with positional headaches from intracranial hypotension in the setting of cerebrospinal fluid overshunting. The patient also had back pain and lumbar radiculopathy, which became more severe after lumboperitoneal shunt placement. On radiographic work-up, there was evidence of right L5 nerve root impingement secondary to a disc bulge and an engorged lumbar epidural venous plexus secondary to overshunting. The patient underwent surgery for a planned L4-5 decompression with a transforaminal lumbar interbody fusion. The operation was complicated by rapid blood loss originating from the epidural venous plexus, and we were unable to safely place the interbody graft.
CONCLUSIONS:
Spinal surgeons need to be aware of the rare diagnosis of radiculopathy secondary to epidural venous plexus engorgement, as it may change the treatment approach or lead to deleterious intraoperative consequences, such as hemorrhage.
PMID: 29248773
DOI: 10.1016/j.wneu.2017.12.027

Liu JKC.
World Neurosurg. 2018 Mar 7. pii: S1878-8750(18)30426-1. doi: 10.1016/j.wneu.2018.02.153. [Epub ahead of print]
Abstract
BACKGROUND:
Intracranial hypotension from cerebrospinal fluid hypovolemia resulting in cerebral herniation is a rare but known complication that can occur following neurosurgical procedures, usually encountered in correlation with perioperative placement of a lumbar subarachnoid drain. Decrease in CSF volume resulting in loss of buoyancy results in downward herniation of the brain without contributing mass effect, causing a phenomenon known as ‘brain sag.’ Unreported previously is brain sag occurring without concomitant occult CSF leak or lumbar drainage.
CASE DESCRIPTION:
This case report describes a patient who underwent bilateral craniotomies for subacute on chronic subdural hematomas with successful decompression, but suffered from an acute neurological deterioration secondary to brain sag. Despite an initial improvement in neurological exam, he subsequently exhibited a progressive neurologic deterioration with evidence of cerebral herniation on neuroimaging, without evidence of continued mass effect on the brain parenchyma. After a diagnosis of ‘brain sag’ was determined based on imaging criteria, the patient was placed in a flat position which resulted in a rapid improvement in neurological exam without any further intervention.
CONCLUSIONS:
This case is unique from previous reports of intracranial hypotension following craniotomy in that the symptoms were completely reversed with positioning alone, without any evidence of active or occult CSF drainage. This report emphasizes that the diagnosis of brain sag should be taken into consideration when there is an unknown reason for neurologic decline after craniotomy, particularly bilateral craniotomies, if the imaging indicates herniation with imaging findings consistent with intracranial hypotension, without evidence of overlying mass effect.
PMID: 29524703
DOI: 10.1016/j.wneu.2018.02.153

Ulrich CT, Fung C, Piechowiak E, Gralla J, Raabe A, Beck J.
Acta Neurochir (Wien). 2018 Mar;160(3):467-470. doi: 10.1007/s00701-018-3466-3. Epub 2018 Jan 19.
Abstract
Idiopathic spinal cord herniation (ISCH) through an anterior dural defect is rare and the cause is uncertain. Recently, through interpreting imaging studies, disc herniation was proposed to be a major cause for ISCH. We describe the case of a 50-year-old woman with progressive myelopathy who was diagnosed with a thoracic spinal cord herniation. Microsurgical exploration revealed an anterior vertical dural defect and a small concomitant disc herniation, occult on the preoperative imaging, which caused the dural defect and led to ISCH. This intraoperative finding corroborates the emerging notion that disc herniation is the underlying cause of ISCH.
PMID: 29350292
DOI: 10.1007/s00701-018-3466-3

Tsai YH, Chen HC, Tung H, Wu YY, Chen HM, Pan KJ, Cheng DC, Chen JH, Chen CC, Chai JW, Shen WC.
J Magn Reson Imaging. 2018 Feb 13. doi: 10.1002/jmri.25976. [Epub ahead of print]
Abstract
BACKGROUND:
Spontaneous intracranial hypotension (SIH) is often misdiagnosed, and can lead to severe complications. Conventional MR sequences show a limited ability to aid in this diagnosis. MR-based intracranial pressure (MR-ICP) may be able to detect changes of intracranial elastance and pressure.
PURPOSE:
To determine whether MR-ICP is able to differentiate SIH patients from normal subjects, improve diagnostic sensitivity, and provide an insight into the pathophysiology.
STUDY TYPE:
Prospective.
SUBJECTS:
Twenty-eight SIH cases with orthostatic headache and 20 healthy volunteers.
FIELD STRENGTH/SEQUENCE:
Cine phase-contrast MRI on a 1.5T scanner.
ASSESSMENT:
Intracranial elastance (IE) was derived from the ratio of the peak-to-peak cerebrospinal fluid (CSF) pressure gradient (PGcsf-pp ) and intracranial volume change, obtained by summing all flows before each sequential cardiac frame.
STATISTICAL TESTS:
Student’s t-test was used to compare the MR-ICP indexes and flow parameters between SIH patients and healthy volunteers (P < 0.01).
RESULTS:
The SIH patients with cervical epidural venous dilatation (EVD) had an IE of 0.121 ± 0.027 mmHg/cm/ml, significantly higher than that of the normal volunteers (0.085 ± 0.027 mmHg/cm/ml; P = 0.002). In contradistinction, the EVD-negative SIH patients, including four with no sign of CSF leaks, had significantly lower IE (0.055 ± 0.012 mmHg/cm/ml) compared with the normal volunteers and the EVD-positive group (P = 0.001, P < 0.001). The EVD-negative patients had significantly lower PGcsf-pp (0.024 ± 0.007 mmHg/cm) compared with the normal volunteers and the EVD-positive group (0.035 ± 0.011 mmHg/cm, 0.040 ± 0.010 mmHg/cm; P = 0.003, P < 0.001). Additionally, the MRI flow study showed a significant decrease in transcranial inflow and outflow of SIH patients (P < 0.01).
DATA CONCLUSION:
We found that the MR-ICP method is potentially more sensitive than morphological MRI in the early diagnosis of SIH. Also, contrary to common belief, our results suggest that an abnormal craniospinal elastance might be the cause of SIH, instead of CSF leak.
PMID: 29437266
DOI: 10.1002/jmri.25976

Ferrante E, Prone V, Rubino F, Ferrante M.
Neurol Sci. 2018 Feb 13. doi: 10.1007/s10072-018-3263-z. [Epub ahead of print]
No abstract available
PMID: 29441482
DOI: 10.1007/s10072-018-3263-z

Tontisirin N, Benjhawaleemas P, Nimmaanrat S, Sathirapanya P, Laohawiriyakamol T, Tran Q, Finlayson RJ.
Reg Anesth Pain Med. 2018 Feb;43(2):205-210. doi: 10.1097/AAP.0000000000000696.
Abstract
Epidural blood patches (EBPs) are routinely used to treat symptoms (eg, headaches) associated with spontaneous intracranial hypotension. Although cerebrospinal fluid leakage commonly involves the periforaminal areas of the cervical or thoracic spine, EBPs have been historically performed at the lumbar level. Recent evidence suggests that targeting the causative spinal segment may provide greater clinical benefits. While previous reports have targeted foraminal leaks with segmental thoracic or cervical injections, we present a case report detailing the novel use of a navigable epidural catheter to perform a selective EBP at the C7/T1 foramen.
PMID: 29140961
DOI: 10.1097/AAP.0000000000000696

Aslan K, Gunbey HP, Tomak L, Ozmen Z, Incesu L.
J Comput Assist Tomogr. 2018 Jan/Feb;42(1):92-99. doi: 10.1097/RCT.0000000000000646.
Abstract
OBJECTIVE:
The aim of this study was to investigate whether the use of combination quantitative metrics (mamillopontine distance [MPD], pontomesencephalic angle, and mesencephalon anterior-posterior/medial-lateral diameter ratios) with qualitative signs (dural enhancement, subdural collections/hematoma, venous engorgement, pituitary gland enlargements, and tonsillar herniations) provides a more accurate diagnosis of intracranial hypotension (IH).
METHODS:
The quantitative metrics and qualitative signs of 34 patients and 34 control subjects were assessed by 2 independent observers. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of quantitative metrics and qualitative signs, and for the diagnosis of IH, optimum cutoff values of quantitative metrics were found with ROC analysis. Combined ROC curve was measured for the quantitative metrics, and qualitative signs combinations in determining diagnostic accuracy and sensitivity, specificity, and positive and negative predictive values were found, and the best model combination was formed.
RESULTS:
Whereas MPD and pontomesencephalic angle were significantly lower in patients with IH when compared with the control group (P < 0.001), mesencephalon anterior-posterior/medial-lateral diameter ratio was significantly higher (P < 0.001). For qualitative signs, the highest individual distinctive power was dural enhancement with area under the ROC curve (AUC) of 0.838. For quantitative metrics, the highest individual distinctive power was MPD with AUC of 0.947. The best accuracy in the diagnosis of IH was obtained by combination of dural enhancement, venous engorgement, and MPD with an AUC of 1.00.
CONCLUSIONS:
This study showed that the combined use of dural enhancement, venous engorgement, and MPD had diagnostic accuracy of 100 % for the diagnosis of IH. Therefore, a more accurate IH diagnosis can be provided with combination of quantitative metrics with qualitative signs.
PMID: 28708719
DOI: 10.1097/RCT.0000000000000646

Clark MS, Diehn FE, Verdoorn JT, Lehman VT, Liebo GB, Morris JM, Thielen KR, Wald JT, Kumar N, Luetmer PH.
Diagn Interv Radiol. 2018 Jan-Feb;24(1):54-59 doi: 10.5152/dir.2017.17220.
Abstract
PURPOSE:
A recently identified and treatable cause of spontaneous intracranial hypotension (SIH) is cerebrospinal fluid (CSF)-venous fistula, and a recently described computed tomography myelogram (CTM) finding highly compatible with but not diagnostic of this entity is the hyperdense paraspinal vein sign. We aimed to retrospectively measure the prevalence of the hyperdense paraspinal vein sign on CTMs in SIH patients without dural CSF leak, in comparison with control groups.
METHODS:
Three CTM groups were identified: 1) SIH study group, which included dural CSF leak-negative standard CTMs performed for SIH, with early and delayed imaging; 2) Early control CTMs, which were performed for indications other than SIH, with imaging shortly after intrathecal contrast administration; 3) Delayed control CTMs, which included delayed imaging. CTMs were retrospectively reviewed for the hyperdense paraspinal vein sign by experienced neuroradiologists, blinded to the group assignment. All CTMs deemed by a single reader to be positive for the hyperdense paraspinal vein sign were independently reviewed by two additional neuroradiologists; findings were considered positive only if consensus was present among all three readers. For positive cases, noncontrast CTs and prior CTMs, if available, were reviewed for the presence of the sign.
RESULTS:
Seven of 101 (7%) SIH patients had contrast in a spinal/paraspinal vein consistent with the hyperdense paraspinal vein sign; no patient in either control group (total n=54) demonstrated the hyperdense paraspinal vein sign (P = 0.0463). The finding occurred only at thoracic levels. Each patient had a single level of involvement. Six (86%) occurred on the right. Four occurred in female patients (57%). The sign was seen on early images in 3 of 7 cases (43%) and on both early and delayed images in 4 of 7 cases (57%). In 2 of 7 patients (29%), a noncontrast CT covering the relevant location was available and negative for the sign. A prior CTM was available in 2 of 7 patients (29%), and in both cases the hyperdense paraspinal vein sign was also evident.
CONCLUSION:
The prevalence of the hyperdense paraspinal vein sign in SIH patients with dural CSF leak-negative standard CTM was 7%. As the sign was not seen in control groups, this sign is highly compatible with the presence of CSF-venous fistula. Since the CTMs were not specifically dedicated to identifying hyperdense paraspinal veins (i.e., they were not dynamic and were not preceded by digital subtraction myelography), the true prevalence of the sign may be higher. Radiologists should scrutinize conventional CTMs for this sign, especially in patients in whom a traditional dural CSF leak is not identified.
PMID: 29217497
DOI: 10.5152/dir.2017.17220
Full text: http://www.dirjournal.org/eng/makale/1753/62/Full-Text

Turel MK, Kerolus MG, O’Toole JE.
J Neurosurg Spine. 2018 Jan 26:1-5. doi: 10.3171/2017.8.SPINE17513. [Epub ahead of print]
Abstract
Ossification of the ligament flavum in the thoracic spine is an uncommon radiological finding in the Western population but can present with back pain, varying degrees of myelopathy, and even paraplegia on occasion. The authors here present the case of a 50-year-old woman with a history of progressive back pain and symptoms of spontaneous intracranial hypotension who was found to have an ossified ligamentum flavum of the thoracic spine resulting in a dural erosion cerebrospinal fluid leak. Surgery involved removal of the ossified ligament flavum at T10-11, facetectomy, ligation of the nerve root, and primary closure of the dura, which resulted in complete resolution of the patient’s symptoms. Radiological, clinical, and intraoperative findings are discussed to assist surgeons with an accurate diagnosis and treatment in the setting of this unusual presentation.
PMID: 29372863
DOI: 10.3171/2017.8.SPINE17513

Vahdani K, McVeigh K, Harrison R, Williams M, Garrott H.
Orbit. 2018 Jan 4:1-4. doi: 10.1080/01676830.2017.1423346. [Epub ahead of print]
Abstract
Intracranial hypotension (ICH) is characterized by low cerebrospinal fluid pressure, postural headaches, and diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI). A variety of ophthalmoparetic manifestations have been reported in the context of the ICH. The authors describe an unusual case of a 64-year-old woman who presented with rapid onset of headaches, bilateral upper-lid ptosis, and blurring of vision within 4 days after sustaining a trivial head injury. She was noted to have bilateral symmetrical ophthalmoplegia and ptosis-simulating chronic progressive external ophthalmoplegia. MRI revealed characteristic features of ICH. Subsequent autologous epidural patch therapy led to resolution of the headache and imaging findings; however, her ptosis and motility disorder persisted. Despite existing therapeutic measures for ICH, irreversible cranial nerve damage may ensue due to significant cerebral decent or ischemic injury.
PMID: 29300676
DOI: 10.1080/01676830.2017.1423346

Chan TLH, Becker WJ, Hu WY, Amoozegar F.
Can J Neurol Sci. 2018 Jan;45(1):111-113. doi: 10.1017/cjn.2017.257. Epub 2017 Nov 6.
PMID: 29103382
DOI: 10.1017/cjn.2017.257