Re-evaluating the Incidence of Idiopathic Intracranial Hypertension in an Era of Increasing Obesity.

PURPOSE: To re-evaluate the population-based incidence of idiopathic intracranial hypertension (IIH) and to determine if it mirrors the rise in obesity. DESIGN: Retrospective, population-based cohort. PARTICIPANTS: All residents of Olmsted County, Minnesota, diagnosed with IIH between January 1, 1990, and December 31, 2014. METHODS: All cases of IIH were identified using the Rochester Epidemiology Project, which is a record-linkage system of medical records for all patient-physician encounters among Olmsted County, Minnesota, residents. All medical records were reviewed to confirm a diagnosis of IIH. The incidence rates of IIH were compared against the incidence of obesity in Minnesota over the same period. MAIN OUTCOME MEASURES: Incidence of IIH, lumbar puncture opening pressures, and body mass index. RESULTS: There were 63 new cases of IIH, yielding an overall age- and gender-adjusted annual incidence of 1.8 per 100 000 (95% confidence interval, 1.3-2.2) between 1990 and 2014. It increased from 1.0 per 100 000 (1990-2001) to 2.4 per 100 000 (2002-2014; P = 0.007). The incidence of IIH was 3.3 per 100 000 in women and 0.3 per 100 000 in men (P ≤ 0.001). In obese women 15 to 44 years of age, the incidence was 22.0 per 100 000 compared with 6.8 per 100 000 among all women in the same age group. A strong correlation was observed between IIH incidence rates and obesity rates in Minnesota (R2 = 0.70, P = 0.008). CONCLUSIONS: The incidence of IIH has increased since 1990, which is highly correlated with the rise in obesity during the same period.

Movement disorders associated with spontaneous CSF leaks: a case series.

IMPORTANCE AND OBJECTIVE: Headache is the most common symptom in spontaneous CSF leaks, frequently associated with additional manifestations. Herein, attention is drawn to movement disorder as a notable manifestation of spontaneous CSF leaks. DESIGN: Four women and one man (ages 51-78 years) with spontaneous CSF leaks and movement disorders were evaluated clinically and by pertinent neuroimaging studies with follow-up of one to seven years (mean 3.2 years). RESULTS: The movement disorder consisted of choreiform movements in two patients, torticollis in one, mixed tremor in one, and parkinsonism in one. All except the last patient had headaches (orthostatic in one, Valsalva maneuver-induced in one, both orthostatic and Valsalva-induced in two, lingering low-grade headache in one). Diffuse pachymeningeal enhancement and sinking of the brain was noted in all. CT-myelography showed definite CSF leak in three and equivocal leak in one, while no leak could be located in the fifth patient. Two patients improved over time with complete resolution of the movement disorder. One responded to epidural blood patch with complete resolution of his choreiform movements. Two patients required surgery and epidural blood patches. Results were drastic but nondurable in one, while complete recovery was achieved in the other. CONCLUSION: Movement disorders are uncommon in spontaneous CSF leaks but occasionally can be one of the major components of the clinical presentation.

Klippel­Trenaunay­Weber syndrome (KTWS) and spontaneous spinal CSF leak: coincidence or link.

OBJECTIVE: To highlight the occurrence of spontaneous cerebrospinal fluid (CSF) leak in the setting of Klippel­Trenaunay­Weber syndrome (KTWS). BACKGROUND: KTWS is a congenital multicomponent disorder of angiogenesis plus limb asymmetry. The cause of spontaneous CSF leaks often remains unknown, but the notion of a pre-existing dural weakness related to a disorder of connective tissue matrix is gaining momentum. REPORT OF CASES AND METHODS: Two women with KTWS developed spontaneous CSF leaks. Each underwent extensive head and spine imaging studies. One patient underwent surgery to treat the CSF leak and later an epidural blood patch upon partial recurrence of her symptoms. The other patient, who had intermittent CSF leak, developed cerebral venous thrombosis requiring several months of anticoagulation therapy. Both patients have histories of visceral bleeding: gastrointestinal in 1 patient and genitourinary in the other. RESULTS: The predominant site of vascular anomaly was the left lower limb in 1 patient and the right upper limb in the other, while the involved limb was larger in 1 patient and smaller in the other. Each patient presented with orthostatic headaches. One had additional choreiform movements and cognitive difficulties that responded to the treatment of the leak. Head magnetic resonance imaging in both patients showed diffuse pachy meningeal enhancement and evidence of sinking of the brain. Computed tomography myelography in 1 patient disclosed the site of the leak; and she underwent surgery to treat the leak, and later an epidural blood patch upon partial recurrence of her symptoms to which she responded well. The other patient had intermittent leak with history of long remission and was reluctant to go through invasive diagnostic or therapeutic measures. CONCLUSION: The occurrence of an uncommon disorder (spontaneous CSF leak) in the setting of a rare congenital disorder in 2 unrelated patients is intriguing. Whether this represents coincidence or a link is not clear but deserves further observations and investigation.

Radioisotope cisternography in spontaneous CSF leaks: interpretations and misinterpretations.

A broadening of the clinical and imaging features of the spontaneous cerebrospinal fluid (CSF) leaks is now well recognized, far beyond what was thought only two decades ago. This has resulted in increasing number of patients with atypical and unusual features who, not unexpectedly, are directed to headache specialists and tertiary referral centers. In many cases, obviously the fundamental question of presence or absence of CSF leak will need to be addressed prior to proceeding with further and often more involved, more invasive, and more costly diagnostic and therapeutic considerations. Radioisotope cisternography often proves to be very helpful in these situations by demonstrating reliable, although indirect, evidences of CSF leak while it is less helpful in directly identifying the exact site of the CSF leakage. In this overview article, the expectations from and the limitations of this diagnostic method are described along with some personal observations in the past 25 years.

Spontaneous low pressure, low CSF volume headaches: spontaneous CSF leaks.

Spontaneous intracranial hypotension typically results from spontaneous cerebrospinal fluid (CSF) leak, often at spine level and only rarely from skull base. Once considered rare, it is now diagnosed far more commonly than before and is recognized as an important cause of headaches. CSF leak leads to loss of CSF volume. Considering that the skull is a rigid noncollapsible container, loss of CSF volume is typically compensated by subdural fluid collections and by increase in intracranial venous blood which, in turn, causes pachymeningeal thickening, enlarged pituitary, and engorgement of cerebral venous sinuses on magnetic resonance imaging (MRI). Another consequence of CSF hypovolemia is sinking of the brain, with descent of the cerebellar tonsils and brainstem as well as crowding of the posterior fossa noted on head MRI. The clinical consequences of these changes include headaches that are often but not always orthostatic, nausea, occasional emesis, neck and interscapular pain, cochleovestibular manifestations, cranial nerve palsies, and several other manifestations attributed to pressure upon or stretching of the cranial nerves or brain or brainstem structures. CSF lymphocytic pleocytosis or increase in CSF protein concentration is not uncommon. CSF opening pressure is often low but can be within normal limits. Stigmata of disorders of connective tissue matrix are seen in some of the patients. An epidural blood patch, once or more, targeted or distant, at one site or bilevel, has emerged as the treatment of choice for those who have failed the conservative measures. Epidural injection of fibrin glue of both blood and fibrin glue can be considered in selected cases. Surgery to stop the leak is considered when the exact site of the leak has been determined by neurodiagnostic studies and when less invasive measures have failed. Subdural hematomas sometimes complicate the CSF leaks; a rebound intracranial hypertension after successful treatment of a leak is not rare. Cerebral venous sinus thrombosis as a complication is fortunately less common, and superficial siderosis and bibrachial amyotrophy are rare. Short-term recurrences are not uncommon, and long-term recurrences are not rare.

Diagnostic criteria for headache due to spontaneous intracranial hypotension: a perspective.

The clinical and radiographic manifestations of spontaneous intracranial hypotension are highly variable and many patients do not satisfy the 2004 International Classification of Headache Disorders criteria. We developed new diagnostic criteria for spontaneous intracranial hypotension based on cases we have seen reflecting the variable manifestations of the disorder. These criteria provide a basis for change when the classification criteria are next revised. The diagnostic criteria consist of A, orthostatic headache; B, the presence of at least one of the following: low opening pressure (≤ 60 mm H(2) O), sustained improvement of symptoms after epidural blood patching, demonstration of an active spinal cerebrospinal fluid leak, cranial magnetic resonance imaging changes of intracranial hypotension (eg, brain sagging or pachymeningeal enhancement); C, no recent history of dural puncture; and D, not attributable to another disorder.

Orthostatic headaches in the syndrome of the trephined: resolution following cranioplasty.

OBJECTIVE: To draw attention to the syndrome of the trephined as a potential cause for orthostatic headaches without cerebrospinal fluid (CSF) leak. BACKGROUND: Orthostatic headaches typically result from CSF leaks but sometimes may occur in conditions without any evidence of CSF leakage. METHODS: A 37-year-old right-handed woman became comatose after a motor vehicle accident with cerebral contusions and massive left cerebral edema. A large frontoparietal craniectomy was carried out. In 5 months, she made good neurologic recovery. Freeze-preserved bone flap was placed back. In several weeks she was functionally near normal. Two years later, she began to complain of orthostatic headache and gradually additional manifestations appeared including progressive gait unsteadiness, imprecise speech, cognitive difficulties, and an increasing left hemiparesis along with progressive sinking of the skull defect and shift of the midline and ventricular distortion. She underwent removal of resorptive sinking bone flap and construction of an acrylic cranioplasty. RESULTS: At 6-month follow-up, there was complete resolution of the orthostatic headaches, remarkable neurologic improvement along with resolution of midline shift and ventricular distortion. CONCLUSION: The syndrome of the trephined is yet another cause of orthostatic headaches without CSF leak.

A PRESsing dissection.

BACKGROUND: Intracranial dissections have been associated with baroreceptor reflex failure. When this occurs labile hypertension may be observed with its own complications, including but not limited to the clinico-radiographic entity, posterior reversible encephalopathy syndrome (PRES). METHODS: Case report and literature review. RESULTS: We describe a case of carotid dissection resulting in PRES. CONCLUSIONS: We believe failure of the baroreceptor reflex due to carotid dissection resulted in hypertension and subsequent posterior reversible encephalopathy syndrome.

Procedural predictors of epidural blood patch efficacy in spontaneous intracranial hypotension.

BACKGROUND AND OBJECTIVE: Epidural blood patch (EBP) is a safe and effective treatment for spontaneous intracranial hypotension (SIH), but clinical and procedural variables that predict EBP efficacy remain nebulous. METHODS: This study is an institutional review board-approved retrospective case series with dichotomized EBP efficacy defined at 3 months. The study included 202 patients receiving 604 EBPs; iatrogenic cerebrospinal fluid leaks were excluded. RESULTS: Of the EBPs, 473 (78%) were single-level, 349 (58%) lumbar, 75 (12%) bilevel, and 56 (9%) multilevel (≥3 levels). Higher volume (OR 1.64; p<0.0001), bilevel (3.17, 1.91-5.27; p<0.0001), and multilevel (117.3, 28.04-490.67; p<0.0001) EBP strategies predicted greater efficacy. Only volume (1.64, 1.47-1.87; p<0.0001) remained significant in multivariate analysis. Site-directed patches were more effective than non-targeted patches (8.35, 0.97-72.1; p=0.033). Lower thoracic plus lumbar was the most successful bilevel strategy, lasting for a median of 74 (3-187) days. CONCLUSIONS: In this large cohort of EBP in SIH, volume, number of spinal levels injected, and site-directed strategies significantly correlated with greater likelihood of first EBP efficacy. Volume and leak site coverage likely explain the increased efficacy with bilevel and multilevel patches. In patients with cryptogenic leak site, and either moderate disability, negative prognostic brain MRI findings for successful EBP, or failed previous lumbar EBP, a low thoracic plus lumbar bilevel EBP strategy is recommended. Multilevel EBP incorporating transforaminal administration and fibrin glue should be considered in patients refractory to bilevel EBP. An algorithmic approach to treating SIH is proposed.

Penetrating Osseous Spicules Causing High-Flow Ventral CSF Leaks in the Setting of Relatively Low BMI : A Preliminary Study.

OBJECTIVE/BACKGROUND: We have anecdotally observed patients with high-flow ventral cerebrospinal fluid (CSF) leaks resulting from penetrating osseous spicules or calcified discs to be relatively thin. The purpose of this study was to explore the validity of this observation and determine if a potential association exists between low body mass index (BMI) and high-flow spinal ventral CSF leaks resulting from such dura-penetrating lesions. METHODS: Sixteen consecutive patients with precisely localized high-flow ventral spinal CSF leaks on dynamic myelography were identified. The cause of the CSF leak was determined. The BMI on the date nearest to and within 2 weeks of myelography was recorded. Utilizing exact sign test, the body mass index was compared to the average BMI from the National Health and Nutrition Examination Survey (Centers for Disease Control), matched to sex and age-range. RESULTS: The cohort consisted of 10 males (63%) and 6 females with a mean age of 54 years (range 37-72 years). In all patients, a spiculated osteophyte/calcified disc was identified at the site of the leak. Fourteen patients (88%) had a BMI below the matched national average, while only two patients (13%) had values above the national average (p = 0.004). CONCLUSIONS: Patients with high-flow ventral CSF leaks resulting from spiculated osteophyte or calcified disc as identified by dynamic myelography are more likely to have a BMI below the U.S. national average, matched for gender and age-range. This exploratory analysis requires confirmation as well as further characterization of potential pathophysiologic mechanisms and impact on radiographic and clinical assessments.

Steroid-responsive encephalopathy associated with autoimmune thyroiditis.

BACKGROUND: Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), often termed Hashimoto encephalopathy, is a poorly understood and often misdiagnosed entity. OBJECTIVE: To characterize the clinical, laboratory, and radiologic findings in patients with SREAT to potentially improve recognition of this treatable entity. DESIGN: Retrospective analysis of clinical features and diagnostic test data. SETTING: Two affiliated tertiary care referral institutions. PATIENTS: Twenty consecutive (6 male) patients diagnosed as having SREAT from 1995 to 2003. MAIN OUTCOME MEASURES: Clinical features and ancillary test findings associated with SREAT. RESULTS: The median age at disease onset was 56 years (range, 27-84 years). The most frequent clinical features were tremor in 16 (80%), transient aphasia in 16 (80%), myoclonus in 13 (65%), gait ataxia in 13 (65%), seizures in 12 (60%), and sleep abnormalities in 11 (55%). All patients were assigned an alternative misdiagnosis at presentation, most commonly viral encephalitis (n = 5), Creutzfeldt-Jakob disease (n = 3), or a degenerative dementia (n = 4). The most frequent laboratory abnormalities were increased liver enzyme levels in 11, increased serum sensitive thyroid-stimulating hormone levels in 11, and increased erythrocyte sedimentation rate in 5. In only 5 patients (25%) did cerebrospinal fluid abnormalities suggest an inflammatory process. Magnetic resonance imaging abnormalities believed to be related to the encephalopathy were present in 5 patients (26%). CONCLUSIONS: The clinical, laboratory, and radiologic findings associated with SREAT are more varied than previously reported. Misdiagnosis at presentation is common. This treatable syndrome should be considered even if the serum sensitive thyroid-stimulating hormone level and erythrocyte sedimentation rate are normal, the cerebrospinal fluid profile does not suggest an inflammatory process, and neuroimaging results are normal. Until the pathophysiologic mechanism of this and other autoimmune encephalopathies is better characterized, we believe that descriptive terms that reflect an association rather than causation are most appropriate for this syndrome.

Efficacy of epidural blood patch with fibrin glue additive in refractory headache due to intracranial hypotension: preliminary report.

BACKGROUND: Injection of fibrin glue mixed with blood into the epidural space to reliably and effectively treat medically refractory orthostatic headache caused by spinal cerebrospinal fluid (CSF) leaks and subsequent intracranial hypotension has recently been described. The study described in this article utilizes an analogous technique to gauge the therapeutic reproducibility of this novel technique. METHODS: Eight patients with medically refractory headache resulting from intracranial hypotension caused by spinal CSF leaks received epidural injections of combined fibrin glue, autologous blood, and Isovue contrast at the L1-2 vertebral level using intermittent fluoroscopic guidance. Pre-procedure, 1-week post-procedure, and 3-month post-procedure headache pain scores were collected and used for comparison. RESULTS: Three out of 8 patients reported relief at 1 week, although 1 of these 3 patients had returned to their baseline pain intensity at 3 months. Four patients reported no change at 1 week, though 2 of these patients had reduction of their chronic headache pain at 3 months. A single patient reported increased pain 1 week after the procedure, which persisted at 12 weeks. Overall, 4 out of the 8 patients had decreased pain scores at 3-month follow-up. CONCLUSIONS: We did not achieve a similar frequency of headache resolution as reported in prior original studies. However, a subset of patients did appear to receive substantial benefit from the combined fibrin glue-blood patching procedure. This technique may prove to be useful in medically refractory cases, including those patients who continue to have symptoms despite the prior administration of conventional epidural blood patches.

Erratum to: Efficacy of epidural blood patch with fibrin glue additive in refractory headache due to intracranial hypotension: preliminary report.

[This corrects the article DOI: 10.1186/s40064-016-1975-1.].

Spontaneous Intracranial Hypotension.

PURPOSE OF REVIEW: Spontaneous intracranial hypotension results from CSF volume depletion, nearly always from spontaneous CSF leaks. Spontaneous intracranial hypotension is increasingly diagnosed in practice; the number of atypical, unconfirmed, and doubtful cases is also increasing, as are treatment failures. These confront neurologists and create many challenges. This review provides neurologists with a guide to diagnosis, evaluation, and treatment of spontaneous intracranial hypotension. RECENT FINDINGS: The clinical spectrum of spontaneous intracranial hypotension is expanding. Spontaneous CSF leak is considered a disorder with a variety of clinical manifestations and imaging features, sometimes quite different from what may be seen after dural puncture. The anatomy of the spontaneous CSF leak is frequently complex, with contributions from disorders of the connective tissue matrix and associated preexisting areas of dural weakness and meningeal diverticula. To locate the site of the leak, CT myelography is still the study of choice. For rapid-flow leaks, dynamic CT myelography has been very helpful, while slow-flow leaks can remain a lingering challenge. The fundamental question of whether a CSF leak is present in uncertain cases can be best answered by radioisotope cisternography. In most cases, epidural blood patch is the main treatment; however, bilevel or multilevel epidural injections are gaining some momentum as treatment for selected cases. SUMMARY: This article outlines various clinical aspects of spontaneous intracranial hypotension, including headache characteristics, CSF changes, and imaging findings and their underlying mechanisms, as well as treatments and disease complications.

Spontaneous CSF leaks: underlying disorder of connective tissue.

Of 58 consecutive patients with spontaneous CSF leaks, nine exhibited features of connective tissue disorder. One had Marfan's syndrome. Five additional patients had hyperflexible joints, of whom four had arachnodactyly, four were tall and slender, two had hyperextensible skin, and one had a strong family history of abdominal aorta aneurysms. Retinal detachment at a young age was noted in two. One patient had bilateral carotid dissections. A dural weakness may predispose patients to spontaneous CSF leak.

Intracranial hypertension after treatment of spontaneous cerebrospinal fluid leaks.

Four patients, aged 10 to 44 years, with spontaneous cerebrospinal fluid (CSF) leaks and intracranial hypotension developed intracranial hypertension after treatment of their CSF leaks. The leak was at the spinal level in all patients (thoracic level, 2; lumbar level, 1; and undetermined, 1). One patient responded to an epidural blood patch. Three patients responded to surgery, of whom 2 had not responded to prior epidural blood patches. Treatment resulted in complete resolution of symptoms, including orthostatic headaches and disappearance of magnetic resonance imaging abnormalities. However, all patients later developed steady headaches different from their previous headaches. None had recurrence of magnetic resonance imaging abnormalities or any evidence of occlusion of cerebral venous sinuses. All had increased CSF opening pressures. One had bilateral papilledema, and another had no venous pulsations on examination of fundi. Follow-up was possible in 2 patients. One responded well to treatment with acetazolamide, and the other improved gradually and was asymptomatic within several months.

Dynamic CT myelography: a technique for localizing high-flow spinal cerebrospinal fluid leaks.

In some patients with spontaneous spinal CSF leaks, leaks are numerous or tears are so large that extrathecal myelographic contrast material is seen at multiple levels during CT, making identification of their source impossible. This study introduces a dynamic CT myelographic technique that provides high temporal and spatial resolution. In this technical note, we describe the utility of this technique in four patients with challenging high-flow spinal CSF leaks.

Cervical artery dissections: evidence for redissection in previously dissected arteries: report of three cases.

OBJECTIVE AND IMPORTANCE: Among patients with spontaneous internal carotid artery (ICA) or vertebral artery dissections, there is a small but significant risk of development of dissection in an uninvolved ICA or vertebral artery at some time in the future. Recurrence of dissection in a previously dissected and healed ICA or vertebral artery is very rare. We retrospectively reviewed more than 400 cases of cervical artery dissections in our cerebrovascular records for 1970 through 2000. CLINICAL PRESENTATION: Three patients with recurrence of dissection in previously dissected and presumably healed ICAs were identified. All three patients were women. Their ages at the time of the initial dissection were 42, 38, and 31 years. Initial ICA dissections were bilateral in all cases, occurring simultaneously in one case and 1 year apart in the other two cases. All dissections were spontaneous. Redissection of a previously dissected and healed ICA in these three patents occurred 11, 6, and 12 years later, respectively. Two patients had fibromuscular dysplasia. CONCLUSION: Our experience with these three cases, from among more than 400 cases of cervical artery dissections treated at our institution, and the very limited number of reported cases in the literature indicate the rarity of recurrence of dissection in previously dissected and healed cervical arteries. An underlying arteriopathy may be suspected in many of these cases. Management requires medical and sometimes surgical approaches.

Rarity of encephalopathy associated with autoimmune thyroiditis: a case series from Mayo Clinic from 1950 to 1996.

Corticosteroid-responsive encephalopathy associated with autoimmune thyroiditis (also called Hashimoto's encephalopathy) is a rare, life-threatening, treatable, and possibly autoimmune condition. We identified nine patients (with the diagnosis made after 1979) who had relapsing encephalopathy compatible with previous reports of Hashimoto's encephalopathy and no other identifiable cause of encephalopathy at Mayo Clinic Rochester. Of these nine patients, three were clinically hypothyroid, four were subclinically hypothyroid, and two were euthyroid. Thyroid antibodies were positive in eight of eight patients in whom these measurements were made. Electroencephalographic abnormalities were identified in eight of the nine patients (89%). Magnetic resonance imaging (MRI) abnormalities considered etiologically related to encephalopathy were present in three patients (33%). An increased protein concentration was noted on cerebrospinal fluid examination in seven patients (78%). Of the six patients who received high-dose glucocorticoid therapy, 5 (83%) had improvement of neurologic symptoms. In conclusion, encephalopathy associated with autoimmune thyroiditis is rare but important to recognize because it may be responsive to high-dose glucocorticoid therapy. We believe that this condition is not caused by thyroid dysfunction or antithyroid antibodies but represents an association of an uncommon autoimmune encephalopathy with a common autoimmune thyroid disease. The term Hashimoto's encephalopathy is a misnomer and should not be used.

Low cerebrospinal fluid pressure syndromes.

Only 12 years ago the first report on pachymeningeal gadolinium enhancement in low-pressure headaches appeared in the literature. In this short interval the enormous impact of MRI on so-called "spontaneous intracranial hypotension" and "low-pressure head-aches" has become obvious. A much broader clinical and imaging spectrum of the disease is now recognized and a substantially larger number of patients is diagnosed. In the past decade there has been remarkable progress in understanding this disorder and its associated cerebrospinal fluid (CSF) dynamics. Some of the older concepts or presumptions have been challenged while novel observations continue to appear in the literature. We are still in the learning phase.