Torcular Herophili classification and evaluation of dural venous sinus variations using digital subtraction angiography and magnetic resonance venographies.

PURPOSE: The configurations of cerebral veins and dural venous sinuses differ not only between individuals, but also between the two brain hemispheres of an individual, making the anatomical classification of the cerebral veins difficult. We evaluated the superior dural venous sinuses and classified their types and variations using magnetic resonance venography (MRV) and digital substraction angiography (DSA). METHODS: A total of 394 patients were studied retrospectively. Superior dural venous sinuses were evaluated and the confluence of the sinuses was classified on 2-dimensional time-of-flight MRV, contrast-enhanced 3-dimensional spoiled gradient recalled echo magnetic resonance imaging, and/or cerebral DSA. Confluens sinuum was divided into three types: true confluence, partial confluence, and non-confluence. RESULTS: Of the three types, partial confluence (type II) was most frequently seen. Co-dominance of the transverse sinuses was most frequently observed. An occipital sinus was observed in 15 % of the patients. There were statistically significant differences between the left transverse sinus agenesis and the presence of the occipital sinus (p < 0.001), between the co-presence of the partial confluence type torcular and the occipital sinus (p = 0.040), and between the co-presence of the fenestrated straight sinus and the occipital sinus (p = 0.010). CONCLUSIONS: Although anatomical variations of dural venous sinuses are seen frequently, classification of venous sinuses helps surgeons in preoperative evaluation and management, and prevention of possible complications. In this study, we think that a comprehensive evaluation and classification of dural venous sinuses is a significant contribution to the literature.

Association between elevated aminotransferase levels and the metabolic syndrome in Northern Turkey.

INTRODUCTION: Elevated aminotransferase levels(ATLs) are alert the physicians for liver-affecting disease and may reflect liver injury. We aimed to determine the prevalence of elevated ATLs and the association of elevated ATLs with the metabolic syndrome (MetS) in a northern province of Turkey. MATERIALS AND METHODS: Elevated ATLs were evaluated among 1,095 individuals of the Tokat Prevalence Study which have been described in detail elsewhere. 1,095 participants had been selected by a simple random sampling method among 530,000 inhabitants in 70 (12 urban and 58 rural) areas in the province of Tokat which is located in the Black Sea Region of Turkey. RESULTS: The prevalence of elevated serum ALT, AST, and ALT and/or AST were found as 11%, 7.2%, and 13.3%, respectively. Increased BMI, fatty liver, and MetS were higher in our general population with elevated ATLs. After exclusion of individuals with hepatitis B or hepatitis C infection, 132 individuals with elevated ATLs (91 male and 41 female) were evaluated. MetS was found in 59 participants and its prevalence was markedly higher in females with elevated ATLs (p < 0.0001). When the males with elevated ATLs were evaluated, the ALT levels of the persons who have no risk of MetS (p =0.007) and the persons who have one risk of MetS (p = 0.001) were lower than the persons with MetS. CONCLUSIONS: Elevated ATLs are common and it's an important cause is MetS in Northern Turkey.

Unilateral isolated incus agenesis: detection by virtual endoscopy.

We report the first case of unilateral incus agenesis in the literature. Preoperative diagnosis by virtual endoscopy further enhances the significance of this case. We present thin-section temporal bone computed tomographic images and 3-dimensional reconstructed views which were all correlated with intraoperative findings. The patient was successfully treated with an ossicular prosthesis replacement.

Unregistered subtracted CT angiography for the visualization of intracranial arteries at or near the skull base: preliminary experience.

PURPOSE: Restrictions with computed tomography angiography (CTA) regarding the visualization of arteries near the skull base are well known. Today, the gold standard for overcoming this is the matched mask bone elimination method. Worldwide use of this method is limited since it requires advanced imaging physics and software. A more simple method was introduced recently that avoided motion artifacts significantly by restraining the patient's head with a vacuum-type head holder. The purpose of this study was to investigate the feasibility of using unregistered subtracted CTA without such head-holding methods. MATERIALS AND METHODS: Of the 42 patients that underwent subtracted CTA, 39 were recruited for this study. Two patients were excluded due to agitation during examination and one due to artifacts of an embolized aneurysm. All the examinations were performed in an 8-channel multidetector CT suite. After performing a non-contrast low-dose CT examination, CTA was carried out using the same scan planes as on the scout images. Images were transferred to a workstation and subtraction was performed. Hard-copy images through identical locations were reviewed by 2 observers, a radiologist and a clinician (neurologist), and visualization of the internal carotid artery and posterior artery systems were scored. Data were analyzed using the Wilcoxon signed-rank test. RESULTS: Significant statistical differences, in favor of subtracted images, were noted in both observers' scores, both for the internal carotid artery and posterior system arteries. The differences in the clinician's scores were more prominent than that of radiologist's. CONCLUSION: These results are promising for the expanded use of the subtraction method, especially in radiology departments that lack the staff and equipment for registered methods.

Selective intraarterial nimodipine treatment in an experimental subarachnoid hemorrhage model.

BACKGROUND AND PURPOSE: Cerebral vasospasm secondary to subarachnoid hemorrhage (SAH) has been a serious clinical problem. The aim of the present study is to evaluate the efficacy of selective intraarterial (IA) nimodipine treatment in a rabbit model of chronic cerebral vasospasm. METHODS: Twenty-two adult New-Zealand rabbits of either sex, weighing 2500-3800 g were used for this study. Following a control angiography, all animals received 1 mL of fresh unheparinized autologuous arterial blood into the cisterna magna. Three days later, the presence of vasospasm was demonstrated angiographically by selective vertebral artery injection. The experimental design was as follows: separate groups of animals (n = 5, in each group) received nimodipine (0.05 mg/kg), papaverine (6 mg/kg), or vehicle intraarterially, after placement of a microcatheter into the vertebral artery. Another group (n = 5) received nimodipine (0.05 mg/kg) directly into the cisterna magna, and vehicle injection was made into cisterna magna in two other animals. Thirty minutes after treatment, angiographies were repeated and changes in arterial diameter were expressed as percentages of control. RESULTS: IA nimodipine and IA papaverine were effective in relieving veretebral and basilary vasospasm (P < .05). IA nimodipine was more effective than IA papaverine (P < .05). IA nimodipine was not more effective than intrathecal (IT) nimodipine in relieving vertebral artery vasospasm, although it was more effective than IT nimodipine in basilar artery. Vehicle injections (IA or IT) failed to reverse the vasospasm induced by autologuous blood injection. CONCLUSION: This study showed that selective IA nimodipine treatment may be considered as an alternative in the treatment of chronic vasospasm following SAH.

Cervical diastematomyelia in cervico-oculo-acoustic (Wildervanck) syndrome: MRI findings.

Cervico-oculo-acoustic (COA) or Wildervanck syndrome is characterized by the triad of Klippel-Feil anomaly, bilateral abducens palsy with retracted bulbs (Duane 'syndrome') and hearing loss. The clinical findings of this syndrome have been well documented. A few case reports with MRI findings have appeared in the literature showing brainstem and cerebellar hypoplasia and vertebral segmentation anomalies. Our case is unique in that diastematomyelia of the lower medulla and cervical cord was accompanied by vermian hypoplasia, tonsillar herniation and resulting triventricular hydrocephalus in a child with Wildervanck syndrome. This case is presented with MR images. Children with Wildervanck syndrome should be investigated for craniospinal abnormalities with MR imaging.