Diffusional kurtosis imaging in hydrocephalus.

PURPOSE: Diffusional kurtosis imaging is an advanced diffusion magnetic resonance imaging method that yields, in addition to conventional diffusion information, non-Gaussian diffusion effects, which may allow a more comprehensive characterization of tissue microstructure. The purpose of this study is to use diffusional kurtosis to assess white matter integrity in patients with hydrocephalus and to determine whether changes in kurtosis correlate with the severity of hydrocephalus and leukoaraiosis (LA), a commonly seen comorbidity in hydrocephalus. METHODS: 26 patients with imaging evidence of hydrocephalus and 26 age- and sex- matched subjects with normal ventricular size were retrospectively analyzed. Standard diffusion tensor imaging and diffusional kurtosis metrics were compared between the two groups. Correlation between kurtosis and severity of hydrocephalus and presence and severity of LA was determined. RESULTS: Hydrocephalus patients relative to controls demonstrated statistically significant decrease in all kurtosis metrics in most brain regions studied. The severity of hydrocephalus was associated with greater decrease in kurtosis in the corpus callosum. There was more LA in the hydrocephalus group, and severity of LA was associated with decrease in kurtosis. After controlling for the degree of LA, kurtosis was still decreased in hydrocephalus relative to the controls. CONCLUSION: Diffusional kurtosis imaging detects microstructural changes in the white matter of patients with hydrocephalus. Our results suggest that hydrocephalus plays a role in altering white matter integrity.

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.

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.

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 structure's development may help to better understand the cause of the high-riding JB and JB diverticulum, both of which may cause clinical symptoms.

Frequency of intraductal papillary mucinous neoplasm in patients with and without pancreas cancer.

PURPOSE: To determine the frequency of intraductal papillary mucinous neoplasm (IPMN) in patients with and without invasive ductal adenocarcinoma (IDAC). METHODS: 82 patients underwent pancreatectomy for pancreas adenocarcinoma. 68/82 subjects underwent at least one preoperative imaging study including CT (n = 43), MRI (n = 25), or both (n = 12). Imaging studies were retrospectively evaluated to determine if IPMN was present in the gland at a location distant from IDAC. In 183 different adult patients undergoing MRI for renal mass, images were evaluated to determine the frequency of IPMN. Fisher's exact test was used to test whether the prevalence of IPMN was greater among patients with pancreas cancer than those without. RESULTS: Five of 68 (7.3%) patients who underwent pancreatic resection for IDAC had IPMN at a site distant from the cancer. Two of 182 (1.1%) patients undergoing MRI for renal cancer had imaging evidence of IPMN. There was a significant difference (p = 0.017) in the prevalence of IPMN between patients with and without IDAC. The odds ratio for IPMN as a predictor of pancreas cancer was estimated as 7.18. CONCLUSION: IPMN occurs with increased frequency in patients with pancreas cancer as opposed to those without pancreas cancer. and IAP.

Balloon catheter dilatation of benign esophageal strictures in children.

PURPOSE: This retrospective study evaluated the safety and efficacy of fluoroscopically guided balloon dilatation of benign pediatric esophageal strictures. MATERIALS AND METHODS: Between 2000 and 2005, 272 esophageal balloon dilatations were performed in 49 children, aged 18 days to 18 years. Chart and primary physician record reviews were used to assess complications, age-appropriate food intake, and dysphagia. Efficacy was calculated by time to recurrent symptoms requiring repeat balloon dilatation. Durability was assessed by the frequency of dilatations. RESULTS: Seventy-seven percent of patients required a second dilatation within 9 months. Survival analysis (Kaplan-Meier) demonstrated no significant difference for efficacy in relation to patient age (P = .76) or stricture cause (P = .56). A decrease in the number of dilatations occurred over time to achieve longer symptom-free intervals. Patients underwent an average of 5.6 dilatations with an average total intervention time of 2 years. Patients were able to remain symptom free for a mean of 110 days. The procedure had a success rate of 100%, the only major complication being an esophageal perforation (complication rate, 0.37%) in a patient with a stricture secondary to correction of a tracheoesophageal fistula. CONCLUSIONS: Balloon esophageal dilatation in children is an effective and safe first-line therapy. Complications are quite rare and manageable. Although cures are unusual, most children require less than one dilatation every 6 months. It is concluded that fluoroscopically guided balloon dilatation should be the primary method of treating benign esophageal strictures.