Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging.

BACKGROUND: Almost 90% of cerebral thromboembolism cases are caused by atherosclerosis. Craniocervical atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30% of all stroke cases. The course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the plaque. Carotid artery stenting (CAS) can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery stenosis. Diffusion-weighted imaging (DWI) is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid endarterectomy. The number and volume of new ischemic lesions are determined using DWI. AIM: To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using DWI. METHODS: Forty-seven male (73.4%) and seventeen female (26.6%) patients (total, n = 64) aged 42-84 years (mean 67.96 ± 8.03 years) diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective study. Twelve of the cases (18.8%) were asymptomatic, while fifty-two (81.2%) were symptomatic. The area where the stenosis was highest was measured, and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial method. DWI of the cases was evaluated by two radiologists experienced in neuroradiology (B.A. with more than 15 years of experience, E.G. with more than 10 years of experience). Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the operation. Since the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS, all lesions within the first 24 h were considered as new ischemias. RESULTS: In the present study, 39 new ischemic lesions were detected in 20 cases. The average number of new lesions after all CAS operations was 0.62. They were mostly located in the occipital lobes, followed by the frontal and parietal lobes. These new ischemic lesions were most common in the middle cerebral artery territory, followed by the posterior cerebral artery territory and middle cerebral artery-posterior cerebral artery watershed areas. New lesions were found in 31.2% (20/64) of patients, including 17 (26.5%) in ipsilateral and three (4.6%) in contralateral hemispheres. New bilateral lesions were detected in one case (1.5%). The average volume of the new ischemic lesions detected by the two observers was 1.10 cm³. The numbers of newly appearing ischemic lesions in DWI after CAS were significantly higher in cases where stenting was applied on the left side of the carotid artery and in cases where longer plaques (> 1 cm) were responsible for the narrowing in symptomatic patients. The stenosis rate was low in the group with ulcerated plaques. CONCLUSION: New ischemic lesions due to CAS appear mostly in the main arterial territory but they may also occur in watershed areas.

Frequency and imaging findings of variations in human aortic arch anatomy based on multidetector computed tomography data.

The purpose of this study was to describe the frequency of the variations in the branching pattern of the aortic arch (AA) according to multidetector computed tomography (MDCT) imaging findings. MDCT images of 1136 consecutive patients who had undergone imaging of the chest were retrospectively examined. Eleven different branching patterns were observed. A left-sided AA with three major branches was seen in 74.4% of the patients. Bovine-type AA (21.1%) and independent origin of the left vertebral artery (3.7%) were the next two most common patterns.

Quantitative MRI analysis of idiopathic carpal tunnel syndrome.

AIM: The aim of this study was to try to find parametric ratios for the diagnosis and pathophysiology of carpal tunnel syndrome using MR. MATERIAL AND METHODS: Dominant side wrist MRI examinations of 27 female carpal tunnel patients and 21 normal females were compared. The carpal tunnel contents area / carpal tunnel cross section area ratio was defined, analysed and discussed with the literature. RESULTS: Carpal tunnel contents / wrist area ratios of the carpal tunnel patients were measured and compared with the control group. This comparison revealed that the proportion of the contents of the carpal tunnel is increased in the carpal tunnel syndrome patients. Palmar bowing was found to be increased and median nerve cross section area was found to be increased at the proximal entrance of the carpal tunnel. CONCLUSION: As Phalen has postulated, the volume of the contents of the carpal tunnel were found to be increased in the carpal tunnel syndrome patients. Carpal tunnel cross section areas remained the same with the control group. This increase can be demonstrated by MRI imaging which can provide an evidence for the pathophysiology of carpal tunnel syndrome.

Spontaneous third ventriculostomy in chronic obstructive hydrocephalus.

INTRODUCTION: Spontaneous ventriculostomy is a rare condition, and only few cases are reported. Cine magnetic resonance imaging can demonstrate the flow from the ventriculostomy. CASE REPORT: A 25-year-old woman with a known tectal glioma and hydrocephalus was proved to have spontaneous third ventriculostomy.

Computed tomography virtual laryngoscopy: comparison between radiological and otolaryngological evaluations for laryngeal carcinoma.

OBJECTIVES: We evaluated the utility of computed tomography virtual laryngoscopy (CTVL) in identifying endolaryngeal lesions in laryngeal tumors. PATIENTS AND METHODS: Virtual laryngoscopic images were obtained from axial CT scans of 21 patients with known laryngeal carcinoma. Findings from rigid telescopic videolaryngoscopy (RTV) and CTVL images were evaluated and compared with reference to operative records. RESULTS: Lesions localized in the base of the tongue, pyriform sinus, aryepiglottic folds, and arytenoids were well visualized by both RTV and CTVL. The two techniques were not found effective in identifying lesions of the ventricular bands, ventricular cavities, and the anterior commissure. Virtual laryngoscopy was superior to RTV in the visualization of the subglottic area and vocal cords. CONCLUSION: Virtual laryngoscopy is a noninvasive and reliable technique that provides visualization of endolaryngeal surfaces and tumor extension. It may be beneficial in staging larynx carcinoma and planning the most appropriate surgical procedure.