Bidyut K. Pramanik

Neurosarcoidosis: presentations and management.

Background:Sarcoidosis affects the central nervous system more frequently than previously appreciated. The diagnosis of neurosarcoidosis is often delayed, potentially leading to serious complications. Symptoms, when present, are not specific, may be subtle and resemble those of other neurologic diseases. Review Summary:During the past decade, significant progress has been made in understanding the epidemiology and pathophysiology of neurosarcoidosis, as well as the ability to diagnose and treat this disease. Studies have shown that the optimal diagnostic imaging modality for neurosarcoidosis is magnetic resonance imaging with gadolinium as it enhances visualization of granulomatous infiltration in neural tissue. Subclinical neurosarcoidosis may not be uncommon in patients with sarcoidosis. It is now evident that neurosarcoidosis does not invariably present as a catastrophic event. Adverse effects associated with high-dose systemic corticosteroids, the standard therapy, have discouraged practitioners from initiating treatment in the absence of significant symptomatic neurologic disease. However, other immunosuppressive agents as well newer biologic agents have emerged as an effective, well-tolerated therapeutic alternative to corticosteroids, which are often effective in corticosteroid-recalcitrant cases. Conclusion:Neurologists should be aware of the varying presentations of neurosarcoidosis since early recognition of neurologic involvement in patients with undiagnosed or proven sarcoidosis is currently possible and critical to the prevention of disabling complications.

Perfusion CT Improves Diagnostic Accuracy for Hyperacute Ischemic Stroke in the 3-Hour Window: Study of 100 Patients with Diffusion MRI Confirmation

Purpose: Conventional noncontrast CT (NCCT) is insensitive to hyperacute cerebral infarction in the first 3 h. Our aim was to determine if CT perfusion (CTP) can improve diagnostic accuracy over NCCT for patients presenting with stroke symptoms in the 3-hour window. Methods: Consecutive patients presenting to our emergency department with symptoms of ischemic stroke <3 h old and receiving NCCT and CTP as part of their triage evaluation were retrospectively reviewed. Patients with follow-up diffusion-weighted MRI (DWI) <7 days from ictus were included. Two readers rated the NCCT and CTP for evidence of acute infarct and its vascular territory. CTP selectively covered 24 mm of brain centered at the basal ganglia with low relative cerebral blood volume in a region of low cerebral blood flow or elevated time to peak as the operational definition for infarction. A third reader rated all follow-up DWI for acute infarct and its vascular territory as the reference standard. Sensitivity, specificity, and predictive values were calculated. An exact McNemar test and generalized estimating equations from a binary logistic regression model were used to assess the difference in detection rates between modalities. A two-sided p value <0.05 was considered significant. Results: 100 patients were included. Sixty-five (65%) patients had follow-up DWI confirmation of acute infarct. NCCT revealed 17 (26.2%) acute infarcts without false positives. CTP revealed 42 (64.6%) acute infarcts with one false positive. Of the 23 infarcts missed on CTP, 10 (43.5%) were outside the volume of coverage while the remaining 13 (56.5%) were small cortical or lacunar type infarcts (≤15 mm in size). CTP was significantly more sensitive (64.6 vs. 26.2%, p < 0.0001) and accurate (76.0 vs. 52%, p < 0.0001) and had a better negative predictive value (59.6 vs. 42.2%, p = 0.032) than NCCT. Conclusion: In a retrospective cohort of 100 patients with symptoms of hyperacute stroke in the 3-hour window, CTP provided improved sensitivity and accuracy over NCCT.

Clinical spectrum of patients with erosion of the inner ear by jugular bulb abnormalities

Anatomic variants of the jugular bulb (JB) are common; however, abnormalities such as large high riding JB and JB diverticulum (JBD) are uncommon. Rarely, the abnormal JB may erode into the inner ear. The goal of our study is to report a large series of patients with symptomatic JB erosion into the inner ear.

Development of the Jugular Bulb: A Radiologic Study

Objective: Jugular bulb (JB) abnormalities such as JB diverticulum and high-riding JBs of the temporal bone can erode into the inner ear and present with hearing loss, vestibular disturbance, and pulsatile tinnitus. Their cause and potential to progress remain to be studied. This comprehensive radiologic study investigates the postnatal development of the venous system from transverse sinus to internal jugular vein (IJV). Setting: Academic medical center. Patients, Intervention, Main Outcome Measure: Measurements of the transverse and sigmoid sinus, the JB, IJV, and carotid artery were made from computed tomographic scans of the neck with intravenous contrast in infants (n = 5), children (n = 13), adults (n = 35), and the elderly (n = 15). Results: Jugular bulbs were not detected in patients younger than 2 years, enlarged in adulthood, and remained stable in the elderly. The venous system was larger in men than in women. From transverse sinus to IJV, the greatest variation in size was just proximal and distal to the JB with greater symmetry observed as blood returned to the heart. Right-sided venous dominance was most common occurring in 70% to 80% of cases. Conclusion: The JB is a dynamic structure that forms after 2 years, and its size stabilizes in adulthood. The determinants in its exact position and size are multifactorial and may be related to blood flow. Improved understanding of this structures development may help to better understand the cause of the high-riding JB and JB diverticulum, both of which may cause clinical symptoms.

Prevalence of Jugular Bulb Abnormalities and Resultant Inner Ear Dehiscence: a Histopathologic and Radiologic Study:

Objective Jugular bulb abnormalities (JBA), including high-riding jugular bulb (HRJB) and jugular bulb diverticulum (JBD), can erode into the inner ear. In this study, the authors investigate the prevalence and consequences of JBA and their erosion into inner ear structures using temporal bone histopathology and computed tomography (CT). Study Design Cross-sectional study of temporal bone histopathology and radiology. Setting Academic medical center. Subjects and Methods In total, 1579 temporal bone specimens and 100 CT of the temporal bones (200 ears) were examined for JBA and any associated dehiscence of inner ear structures. Temporal bone specimens were examined for histological consequences of inner ear erosion. Jugular bulb dimensions were measured on axial CT scans and compared across groups. Accompanying demographic and clinical information were reviewed. Results High jugular bulbs were noted in 8.2% (130/1579) of temporal bone specimens and in 8.5% (17/200) of temporal bone CT. The prevalence of JBA increases during the first 4 decades of life and stabilizes thereafter. High-riding jugular bulbs eroded inner ear structures such as the vestibular aqueduct, vertical facial nerve, or posterior semicircular canal in 2.8% (44/1579) of cases histologically and 1.5% (3/200) radiologically. In most, jugular bulb–mediated inner ear dehiscence was clinically and radiologically silent. Conclusion Jugular bulb abnormalities are common. They are present in 10% to 15% individuals and are primarily acquired by the fourth decade of life. In 1% to 3% of cases, the HRJB erodes into the inner ear and most frequently involves the vestibular aqueduct.

A Clinical and Histopathologic Study of Jugular Bulb Abnormalities

OBJECTIVE To further define the spectrum of clinical presentation and explore the histologic sequelae of jugular bulb abnormalities (JBAs). DESIGN Retrospective review. SETTING Academic medical center. PATIENTS Thirty patients with radiologic evidence of inner ear dehiscence by JBA. MAIN OUTCOME MEASURE Thirty patients with radiologic inner ear dehiscence by JBA and 1579 temporal bone specimens were evaluated for consequences from JBA. RESULTS We found that JBA-associated inner ear dehiscence could be identified on computed tomography of the temporal bone but not on magnetic resonance imaging scan. Jugular bulb abnormalities eroded the vestibular aqueduct most often (in 25 patients), followed by the facial nerve (5 patients) and the posterior semicircular canal (4 patients). Half of the patients (15) were asymptomatic. Results from vestibular evoked myogenic potential (VEMP) tests were positive in 8 of 12 patients with inner ear dehiscence. Histologically, only 2 of 41 temporal bones with dehiscence of the vestibular aqueduct demonstrated endolymphatic hydrops. CONCLUSIONS Jugular bulb abnormalities can erode into the vestibular aqueduct, facial nerve, and the posterior semicircular canal. While symptoms may include pulsatile tinnitus, vertigo, or conductive hearing loss, in contrast to earlier reports, half of the patients were asymptomatic. Dehiscence of vestibular aqueduct rarely leads to clinical or histologic hydrops. The VEMP testing was useful in confirming the presence of inner ear dehiscence due to JBAs. Because the natural history of JBAs is unknown, these patients should be followed closely to evaluate for progression of the JBA or development of symptoms.

Spontaneous development of bilateral subdural hematomas in an infant with benign infantile hydrocephalus: color Doppler assessment of vessels traversing extra-axial spaces

We present an infant with macrocrania, who initially demonstrated prominent extra-axial fluid collections on sonography of the brain, compatible with benign infantile hydrocephalus (BIH). Because of increasing macrocrania, a follow-up sonogram of the brain was performed; it revealed progressive enlargement of the extra-axial spaces, which now had echogenic debris. Color Doppler US showed bridging veins traversing these extra-axial spaces, so it was initially thought that these spaces were subarachnoid in nature (positive cortical vein sign). However, an arachnoid membrane was identified superior to the cortex, and there was compression of true cortical vessels beneath this dural membrane. An MRI of the brain showed the extra-axial spaces to represent bilateral subdural hematomas. The pathogenesis of spontaneous development of the subdural hematomas, in the setting of BIH, is discussed. We also emphasize that visualizing traversing bridging veins through extra-axial spaces does not necessarily imply that these spaces are subarachnoid in origin.

Venous malformations of the temporal bone are a common feature in CHARGE syndrome

CHARGE (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, and Ear abnormalities and/or deafness) syndrome is a genetic disorder with prominent otolaryngologic features including choanal atresia and inner ear malformations. Recent experience with venous malformations during cochlear implant surgery prompted this study to define the spectrum of venous abnormalities in CHARGE and their surgical implications in otology.

Large jugular bulb abnormalities involving the middle ear.

Objective Jugular bulb abnormalities (JBA), such as jugular bulb diverticula (JBD) or large jugular bulbs, rarely present in the middle ear. We review a large series of temporal bone histopathologic specimens to determine their prevalence and present a series of cases of JB abnormalities involving the middle ear (JBME) that shed light on the probable mechanism for their development. Patients 1,579 unique temporal bone specimens and individuals with radiographically-diagnosed JBME. Intervention Histopathologic and clinical review of temporal bone specimens and patient presentations, radiographic findings, treatments and outcomes. Main Outcome Measure Shared characteristics of JBME. Results There were 17 cases of JBME in 1,579 temporal bone (1.1%), of which, 15 involved the inferior mesotympanum below the level of the round window membrane (RWM), whereas 2 encroached upon the RWM or ossicles. In addition, 4 clinical cases of large JBME extending above RWM were encountered; these occurred in both sexes with ages spanning from young to old (7–66 yr). They presented with conductive hearing loss (n = 3), ear canal mass (n = 1), and intraoperative bleeding (n = 1). Radiologically, they had multiple diverticula of the JB on the side with JBME, with 1 patient demonstrating growth on serial imaging studies. All patients who underwent additional imaging had marked hypoplastic contralateral transverse sinus. Conclusion JBME abnormalities are rare, present across age groups, and may demonstrate serial growth over time. They are usually associated with multiple other diverticula within the same JB. Our clinical series suggests that JBME’s development and uniquely aggressive behavior results from contralateral transverse sinus outflow obstruction.

Utility of sagittal reformatted computerized tomographic images in the evaluation of the frontal sinus outflow tract.

Background Anatomic and mucosal obstruction of the frontal sinus outflow tract (FSOT) can result in frontal sinusitis often associated with frontal headache. Thorough evaluation of symptomatic patients requires axial and coronal computerized tomographic (CT) scans of the paranasal sinuses (PNS). With the advent of multichannel multidetector CT scanning, the availability of high-quality sagittal images has become increasingly widespread. However, the utility of these images in the assessment of FSOT patency has not yet been established. Methods A retrospective review of coronal and sagittal images from 25 PNS CT scans (50 sides) were randomized, blinded, and independently evaluated by two neuroradiologists. FSOT obstruction by agger nasi cells, the ethmoid bulla, and mucosal disease was assessed. A degree of confidence was rendered for each of these findings. The results were then compared against a consensus diagnosis, which was rendered based upon simultaneous reading of the coronal and sagittal images. Generalized estimating equations were used to assess the difference between sagittal and coronal images in terms of reader confidence and diagnostic concordance with the consensus. Results Review of sagittal images had a higher degree of concordance with the consensus than did coronal images, and was highest for mucosal disease. Both readers were more confident in rendering a diagnosis based upon the sagittal images. Conclusion Sagittal reformatted CT images of the PNS are helpful in the radiologic evaluation of the FSOT. Experienced neuroradiologists had a higher degree of confidence in the diagnosis of the obstruction of the FSOT using sagittal reformatted images.