Linda P. Kelly

Clinical course of idiopathic intracranial hypertension with transverse sinus stenosis

Objective: Transverse sinus stenosis (TSS) is common in idiopathic intracranial hypertension (IIH), but its effect on the course and outcome of IIH is unknown. We evaluated differences in TSS characteristics between patients with IIH with “good” vs “poor” clinical courses. Methods: All patients with IIH seen in our institution after September 2009 who underwent a high-quality standardized brain magnetic resonance venogram (MRV) were included. Patients were categorized as having a good or poor clinical course based on medical record review. The location and percent of each TSS were determined for each patient, and were correlated to the clinical outcome. Results: We included 51 patients. Forty-six patients had bilateral TSS. The median average percent stenosis was 56%. Seventy-one percent of patients had stenoses >50%. Thirty-five of the 51 patients (69%) had no final visual field loss. Eight patients (16%) had a clinical course classified as poor. There was no difference in the average percent stenosis between those with good clinical courses vs those with poor courses (62% vs 56%, p = 0.44). There was no difference in the percent stenosis based on the visual field grade (p = 0.38). CSF opening pressure was not associated with either location or degree of TSS. Conclusion: TSS is common, if not universal, among patients with IIH, and is almost always bilateral. There is no correlation between the degree of TSS and the clinical course, including visual field loss, among patients with IIH, suggesting that clinical features, not the degree of TSS, should be used to determine management in IIH.

MRI findings of elevated intracranial pressure in cerebral venous thrombosis versus idiopathic intracranial hypertension with transverse sinus stenosis

ABSTRACT We wished to determine whether magnetic resonance imaging signs suggesting elevated intracranial pressure are more frequently found in patients with idiopathic intracranial hypertension (IIH) than in those with cerebral venous thrombosis (CVT). Among 240 patients who underwent standardised contrast-enhanced brain magnetic resonance brain imaging and venography at our institution between September 2009 and September 2011, 60 with abnormal imaging findings on magnetic resonance venography were included: 27 patients with definite and 2 patients with presumed idiopathic intracranial hypertension, and 31 with definite cerebral venous thrombosis. Medical records were reviewed, and imaging studies were prospectively evaluated by the same neuroradiologist to assess for presence or absence of transverse sinus stenosis, site of cerebral venous thrombosis if present, posterior globe flattening, optic nerve sheath dilation/tortuosity, and the size/appearance of the sella turcica. Twenty-nine patients with idiopathic intracranial hypertension (28 women, 19 black, median age: 28, median body mass index: 34  kg/m2) had bilateral transverse sinus stenosis. Thirty-one CVT patients (19 women, 13 black, median age: 46, median body mass index: 29) had thrombosis of the sagittal (3), sigmoid (3), cavernous (1), unilateral transverse (7), or multiple (16) sinuses or cortical veins (1). Empty/partially empty sellae were more common in IIH (3/29 and 24/29) than in cerebral venous thrombosis patients (1/31 and 19/31) (p < 0.001). Flattening of the globes and dilation/tortuosity of the optic nerve sheaths were more common in idiopathic intracranial hypertension (20/29 and 18/29) than in cerebral venous thrombosis (13/31 and 5/31) (p < 0.04). We conclude that although abnormal imaging findings suggestive of raised intracranial pressure are more common in IIH, they are not specific for that disorder and are found in patients with raised intracranial pressure from other causes such as cerebral venous thrombosis.

Teaching Ophthalmoscopy to Medical Students (TOTeMS) II: A One-Year Retention Study

OBJECTIVE: We previously demonstrated that medical students (MS) performed more accurately and preferred using photographs than direct ophthalmoscopy to examine the ocular fundus. We hypothesized that these differences would persist over time. BACKGROUND: Learning direct ophthalmoscopy is challenging, and MS long-term retention of ophthalmoscopy skills is poor. DESIGN/METHODS: One year after initial training, second-year MS were randomized and reevaluated on their ability to examine the ocular fundus using either fundus photographs or direct ophthalmoscopy on eye simulators. Positive and negative affect, preferences, and clinical experiences with ocular fundus examination were assessed. RESULTS: 107/119 students (90%) who participated in the original study completed this one-year retention study. Students answered 34/48 (71%) questions correctly using photographs and 31/48 (65%) correctly using ophthalmoscopy (p<.01). Both photograph and ophthalmoscopy groups answered five fewer questions correctly on average than one year prior (p<.001). Students rated photographs as “easier than ophthalmoscopy” (8/10 vs. 6/10, respectively; p<.001). Students’ positive affect scores were higher in the photograph group (26.5) than in the ophthalmoscopy group (23.2; p=.03). Students tested on simulators reported lower positive affect than one year ago (decrease of 6.4 points, p<0.001). Students’ self-reported median frequency of fundus examination over the preceding year was <10% (IQR 0-20%). Ocular fundus examination was not performed because of discomfort with the examination (38%), discouragement by their preceptor (20%), and insufficient time (15%). 79% of students felt uncomfortable with ophthalmoscopy, and 44% stated that they would not perform ophthalmoscopy during a general physical examination. 76% stated they would prefer using photographs instead of ophthalmoscopy for fundus examination. CONCLUSIONS: Students preferred photographs for examining the ocular fundus and were more accurate using photographs vs. direct ophthalmoscopy one year after training. The increasing availability of non-mydriatic ocular fundus photography may allow more frequent and accurate examination of the ocular fundus by MS and non-ophthalmologists in many clinical settings. Study Supported by: Research to Prevent Blindness, NIH/NEI P30-EY06360, K23-EY019341 Disclosure: Dr. Mackay has nothing to disclose. Dr. Garza has nothing to disclose. Dr. Bruce has received personal compensation for activities with Kaiser Permanente. Dr. Bruce has received research support from Pfizer, Inc. and Teva Neuroscience. Dr. Bidot has nothing to disclose. Dr. Kelly has nothing to disclose. Dr. Graubart has nothing to disclose. Dr. Newman has received personal compensation for activities with Santhera. Dr. Biousse has received personal compensation in an editorial capacity for Up To Date.

Does bilateral transverse cerebral venous sinus stenosis exist in patients without increased intracranial pressure

OBJECTIVE Transverse cerebral venous sinus stenosis (TSS) is common among patients with idiopathic intracranial hypertension. TSS likely also exists among individuals with normal intracranial pressure (ICP) but the prevalence is unclear. The goal of this study was to identify patients with incidental TSS and normal ICP and describe their characteristics. METHODS Among 240 adult patients who underwent brain magnetic resonance imaging (MRI) with magnetic resonance venography (MRV) with contrast at our institution between September 2009 and September 2011, 44 had isolated TSS without further substantial imaging abnormality. Medical records were reviewed for symptoms of increased ICP, papilledema, cerebrospinal fluid (CSF) constituents and opening pressure (OP), and reason for brain imaging. Of these, 37 were excluded for confirmed or possible idiopathic intracranial hypertension. Of the remainder, 5 had CSF-OP≤25 cmH2O without papilledema, and 2 did not have measured ICP, but had no papilledema or symptoms of increased ICP. Imaging was re-interpreted to assess for signs suggestive of elevated ICP and to characterize the TSS further. RESULTS All patients were women (mean age: 41, mean BMI: 37.1). CSF contents were normal, but OPs were at the upper limit of normal (22-25 cmH2O). Indications for MRI/MRV included query pituitary abnormality (1), migraine (4), and anomalous-appearing optic nerves (2). All had bilateral TSS. Six had short TSS and an empty sella; 1 had long TSS and no empty sella; 1 had flattening of the posterior sclera; 2 had prominence of peri-optic nerve CSF. CONCLUSION Asymptomatic bilateral TSS exists in patients with ICP≤25 cmH2O, but is likely uncommon. CSF-OP was at the upper limit of normal in our patients, who also had other radiologic signs suggestive (but not specific) of chronically-raised ICP. Findings of bilateral TSS on imaging should prompt funduscopic examination for papilledema.

Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is a disorder characterized by increased intracranial pressure of unknown cause. It most commonly affects young, obese females of childbearing age. Progressive visual field loss from papilledema is the most severe morbidity, and formal visual fields must be used to monitor patients. Some patients, particularly those who are male, black, or very obese, appear to have a higher risk of visual loss. Weight loss is a key treatment. Acetazolamide is commonly used, but its efficacy is uncertain. Cerebrospinal fluid diversion and optic nerve sheath fenestration are used for surgical management in progressive and fulminant cases.