Brain MRI as a predictor of CSF tap test response in patients with idiopathic normal pressure hydrocephalus

In this study, our objective was to identify the characteristic morphological features of brain MRI associated with a positive cerebrospinal fluid (CSF) tap test in patients with idiopathic normal pressure hydrocephalus (iNPH). Patients diagnosed with clinical suspected iNPH were evaluated. All patients underwent a mini-mental state examination, a brain MRI, and a CSF tap test. The severities of clinical symptoms were rated before and after the CSF tap test. Characteristic brain MRI findings including frontal convexity narrowing, parietal convexity narrowing, upward bowing of the corpus callosum, empty sella, narrowing of the CSF space at the high convexity, marked dilatation of the Sylvian fissure, and disproportion between narrowing of the CSF space at the high convexity and dilatation of the Sylvian fissure (“mismatch” sign) on T1-weighted or FLAIR image were analyzed. Forty-three patients (33 males/ten females, mean age 76.9 ± 6.9 years) with possible iNPH participated in this study. The presence versus absence of empty sella (52.4 vs. 14.3%, OR 6.6, 95% CI 1.5–29.4, p = 0.02) and “mismatch” sign (45.5 vs. 9.5%, OR 7.9, 95% CI 1.5–42.5, p = 0.02) were associated with positive CSF tap test responses. The sensitivity, specificity, positive predictive value, and negative predictive value of the presence of either of these two MRI features in the prediction of CSF tap response were 72.7, 81, 80, and 73.9%, respectively. Specific brain MRI features can be used as markers for the identification of potential CSF tap test responders in iNPH patients. These features may serve as supplemental evidence in the diagnosis of iNPH patients.     

Trigeminal herpes zoster and Ramsay Hunt Syndrome with a lesion in the spinal trigeminal nucleus and tract

We report the case of a 77-year-old immuno-competent man who developed herpes zoster in the maxillary and mandibular branches of the trigeminal nerve. Within 3 weeks, he developed ipsilateral peripheral facial palsy, hearing loss, vesicles over the external auditory canal, and pain in the face and ear. A T₂-weighted MRI of the brain revealed a hyper-intense lesion at the right medulla corresponding to the spinal trigeminal nucleus and tract. Gadolinium enhancement was seen over the right facial nerve. These lesions suggest a possibility of transaxonal spread of the varicella zoster virus between the trigeminal nerve, the facial nerve, and the spinal trigeminal nucleus and tract.     

Correlation of magnetic resonance images with neuropathology in acute Wernicke's encephalopathy

We correlated serial brain MRIs with neuropathological findings in a 16-year-old female whose autopsy was consistent with Wernicke's encephalopathy (WE). Diffusion-weighted imaging, diffusion coefficients mapping and neuropathology findings were suggested vasogenic edema in the periaqueductal and peri-the-fourth ventricular areas. This is the first documented case report to make this direct comparison. The characteristic WE changes in the mammillary body was also correlated with the findings of MRI with contrast enhancement. Bilateral cortical lesions revealed by MRI were atypical and rare in WE and were not evidenced by pathological changes.     

Nimodipine for treatment of primary thunderclap headache

Eleven patients with primary thunderclap headache (TCH) were treated with oral nimodipine 30 to 60 mg every 4 hours or IV nimodipine 0.5 to 2 mg/h if the oral regimen failed or images showed cerebral vasospasm. With oral nimodipine, headache did not recur in the nine patients without vasospasm. IV nimodipine was given in two patients with vasospasm, including one who developed ischemic stroke. Nimodipine may be effective for TCH. Vasospasm may warrant IV nimodipine.     

Kyphosis correction and height restoration effects of percutaneous vertebroplasty

BACKGROUND AND PURPOSE: Percutaneous vertebroplasty is known for its pain-relieving effect. Our purpose was to evaluate its effect on the kyphosis angle, wedge angle, and height of the fractured vertebral body. METHODS: We reviewed digital radiographs of 73 vertebral bodies in 53 patients before and after vertebroplasty. We measured the spinal kyphosis angle and the wedge angle of the fractured vertebral body. Ratios of the height of the anterior border, center, and posterior borders of the collapsed vertebra to the height at the posterior border of an adjacent normal vertebral body were measured. Gain from vertebroplasty and the restoration percentage (gain divided by loss) were calculated for each parameter. RESULTS:The kyphosis angle, wedge angle, anterior height, center height, and posterior height significantly improved after vertebroplasty. The mean reduction in the kyphosis angle was 4.3 degrees, and the wedge-angle reduction was 7.4 degrees. The mean wedge-angle reduction in fractured vertebral bodies containing gas was 10.2 degrees. Restoration percentages for the kyphosis angle and wedge angle were 19% and 44%, respectively. Gain in the height of the fractured vertebral bodies was 16.7% for the anterior border, 14% for the center, and 7% for the posterior border. Restoration percentages for the height of the vertebral body were 29% for the anterior border and 27% for the center. CONCLUSION: Vertebroplasty increases the height of the fractured vertebra and reduces the wedge and kyphosis angles. These effects are most remarkable in fractured vertebra containing gas.     

Collapsed superior ophthalmic veins in patients with spontaneous intracranial hypotension

The authors measured the average diameter of bilateral superior ophthalmic veins (SOV) in 13 patients with spontaneous intracranial hypotension (SIH) on contrast-enhanced, coronal, T1-weighted MRI. Compared with sex- and age-matched neurology inpatients with normal CSF pressure, the SIH group had a smaller SOV diameter (0.90 vs 1.85 mm, p < 0.001), which partly reversed after treatment (1.09 vs 0.90 mm, p = 0.045, n = 7). Collapsed SOV might provide an additional MRI finding for SIH.     

Headache profile in patients with idiopathic hypertrophic cranial pachymeningitis

BACKGROUND: Idiopathic hypertrophic cranial pachymeningitis (IHCP) is an uncommon disorder due to localized or diffuse thickening of the dura mater. While headache is the most common manifestation, the clinical characteristics of the headache in IHCP have not been well characterized. METHODS: From 1996 to 2002, 6 consecutive patients with IHCP presenting with headache were reviewed (3 women, 3 men; mean age: 49 years). Diagnosis was based on characteristic neuroimaging findings and the exclusion of secondary causes of cranial pachymeningitis. This study reported the headache characteristics, neuroimaging features, and longitudinal follow-up. RESULTS: Chronic daily headache, especially chronic migraine, was the most common headache pattern observed (4/6 patients). Lateralization of headache location appeared to correlate with the distribution of the hypertrophied dural lesions. Diagnostic delay was due to failure to evaluate with gadolinium-enhanced MRI. After treatment, headache (5/6, 83%) and neurologic deficits (2/3, 67%) improved in most patients; however, follow-up MRIs (n = 5) showed deterioration in 3 patients. CONCLUSION: The headache of IHCP is typically a chronic daily headache, often resembling chronic migraine. Correspondingly, IHCP should be considered in the differential diagnosis of refractory chronic daily headache, with or without associated cranial neuropathy or other associated neurologic deficits. The typical imaging finding on gadolinium-enhanced MRI is localized or diffuse pachymeningitis and failure to order a gadolinium-enhanced MRI is the primary reason for delayed diagnosis. Despite symptomatic improvement on longitudinal follow-up, the MRI abnormalities may not improve in parallel with the clinical symptoms.     

Evaluation of clinical and MR findings for the prognosis of spinal epidural haematomas

AIM: The potential of MR and clinical findings of spinal epidural haematomas (SEHs), particularly the early MR findings, to help minimize delays in diagnosis, to aid prognosis and as a reference for conservative treatment, are evaluated. METHODS: Retrospectively 20 patients with SEHs (14 men and 6 women) were examined to record their neurological deficit, MR findings, management, clinical outcome, and interval between symptom onset and MRI or surgery. Two-tailed Fisher's exact test was used for these analyses. RESULTS: Of 8 patients with severe neurological deficit at the onset of symptoms, none had obvious clinical improvement after either surgical or conservative management. Of 12 patients with mild to moderate deficits, 11 (92%) showed improvement or recovery of clinical symptoms. T2-weighted images revealed myelopathy or infarction of the compressed spinal cord in 9 patients, 7 (78%) of whom had no improvement in neurological deficit with either conservative or surgical management. Images in 6 patients showed contrast enhancement in the haematomas. CONCLUSION: Poor clinical outcomes were observed mainly in those with severe neurological deficit and hyperintensity on T2-weighted images of the involved spinal cord. Surgery did not appear to improve outcome in many of these patients. In acute SEHs, MRI showed characteristic findings, such as contrast enhancement, which should not be confused with signs of inflammatory or neoplastic epidural disease.     

Posterior cranial fossa crowdedness is related to age and sex: an magnetic resonance volumetric study

PURPOSE: To measure 3-dimensional (3D) posterior cranial fossa (PCF) crowdedness and to evaluate the effect of age, sex, and body height on PCF. MATERIAL AND METHODS: Fifty-two healthy volunteers (24 M and 28 F; mean age 55.4 +/- 17.2 years; range 24-82 years) were recruited. Using a semi-automated magnetic resonance technique, we calculated a PCF crowdedness index (CI) as the ratio of hindbrain (HB) volume to PCF volume x 100% and correlated this index with age, sex, body height, and other crowdedness parameters. RESULTS: The mean PCF CI was 93.7 +/- 2.7%. Women had a more crowded PCF than men (95.0+1.7% versus 92.1 +/- 2.7%; P<0.001). PCF CI declined with age for both men (r = -0.61; P=0.002) and women (r = -0.68; P<0.001). The association with age--but not HB volume was maintained after we controlled for sex and body height. On multiple regression, both age and sex accounted for 57.5% of the PCF CI variance. CONCLUSION: Our study shows that PCF CI is associated with age and sex, and can therefore be used as a surrogate to assess hindbrain atrophy in a cross-sectional sample. Moreover, sex- and age-specific normal ranges may be needed to evaluate the PCF CI in clinical practice.     

Epileptic seizures in a patient by immersing his right hand into hot water

We report on a 22-year-old assistant cook, presenting with seizures evoked by immersing his right hand into hot water of 40-46 degrees C. His seizure pattern consisted of either simple partial seizures of a tingling sensation arising in the right hand and marching to the right shoulder or a similar attack evolving to a complex partial seizure. Video-EEG monitoring recorded habitual seizures originating from the left centro-temporo-parietal region, compatible with lesions seen on brain magnetic resonance imaging. He responded well to antiepileptic drug treatment and wearing gloves while working in the kitchen. In this patient, hot water of 40-46 degrees C could maximally stimulate skin warm thermoreceptors in the right hand whereby afferent impulses subsequently activated the epileptogenic focus, adjacent to or in the sensory cortex, and elicited seizures.