Ozenc Minareci

Single-voxel proton MR spectroscopy in toluene abuse

Inhalation of toluene, which is an organic solvent, causes toxic encephalopathy characterized by cognitive impairment, cerebellar and extra-pyramidal symptoms. We studied cranial MR images and single-voxel MR spectroscopy of 22 toluene abusers and age-matched control subjects. The mean age of the abusers and mean duration of abuse were 18,1 years and 47 months, respectively. We got three MR spectra from the centrum semiovale, cerebellum and thalamus by using STEAM sequence with a TE value of 30 ms. N-acetyl aspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr, myo-inositol (mI)/Cr peak integral ratios were calculated. NAA/Cr in the cerebellum and centrum semiovale of the abusers were significantly lower than those of the control subjects. mI/Cr in centrum semiovale and cerebellum were higher in toluene abusers. No significant difference was found in the metabolite ratios of the thalami. The association of NAA/Cr and mI/Cr ratios in cerebellum and centrum semiovale with the duration of abuse was significant. Normal level of NAA in thalamus, which was a neuron rich gray matter structure, might imply that toluene inhalation did not cause direct neuronal injury. Selective reduction of NAA and increased level of mI in white matter supported the theory of that axonopathy and gliosis were the main mechanisms of pathophysiology in chronic toluene encepholopathy. Insignificance of elevation of Cho/Cr ratios demonstrated that toluene inhalation did not cause active demyelination.

CT in lobar atrophy of the liver caused by alveolar echinococcosis

We reviewed the CT findings of 13 patients with histologically proved alveolar echinococcosis of the liver. Seven of these patients had hilar involvement, which caused dilatation of intrahepatic bile ducts and invasion of the portal vein or portal branches. In two of these patients we found marked atrophy of the right lobe and in one patient marked atrophy of the left lobe in addition to various CT findings previously reported for alveolar echinococcosis of the liver. The occurrence of lobar atrophy of the liver caused by alveolar echinococcosis has not been previously reported. We concluded that, when a mass lesion with hilar infiltration causing lobar atrophy is found in endemic areas, alveolar echinococcosis should be considered in the differential diagnosis in addition to malignant neoplasms.

Endovascular treatment of a superior mesenteric artery aneurysm secondary to Behcet's disease with Onyx (ethylene vinyl alcohol copolymer).

Behcet’s disease is a complex multisystemic chronic inflammatory disease that is characterized by oral and genital aphtous ulcers and vasculitis. Aneurysms of major arteries are the most important cause of mortality in Behcet’s disease. Four patients with superior mesenteric artery (SMA) aneurysms related to Behcet’s disease have been reported in the literature. We report here the first successful endovascular treatment of a giant, wide-necked SMA aneurysm secondary to Behcet’s disease. We performed a balloon-assisted embolization technique using ethylene vinyl alcohol copolymer (Onyx, ev3, Irvine, CA, USA). There were no signs of recurrence during 2-year follow-up.

A new MRI method for the quantitative evaluation of extraocular muscle size in thyroid ophthalmopathy

In cross section, extraocular muscles are more or less elliptical, with short and long diameters. We studied the ratio (R) of short to long diameter and investigated its use in quantitative assessment of the extraocular muscles in patients with Gravess disease. We measured the diameters on T1-weighted axial and coronal MRI and computed R for each extraocular muscle in 80 patients without and 40 with Gravess disease. We compared the measurements and R of the right and left orbits, and of men and women. The short diameter of all extraocular muscles apart from the superior oblique showed significant differences between men and women, and that of the inferior rectus varied significantly with age. R, however, was unrelated to sex or age. All patients with Gravess disease and an increased short diameter also had an increased R, but 6% of the muscles showed an increase in R, even though their short diameter was within the normal range.

Diffusion MR findings in cyclosporin-A induced encephalopathy

Cyclosporin encephalopathy is a well-known entity, which is clinically characterized by altered mental status, vision problems, focal neurological deficits and seizures. The exact pathophysiology of the cyclosporin encephalopathy has not yet been defined. We report the diffusion-weighted MR imaging and proton MR spectroscopy findings in a case of cyclosporin encephalopathy. The white-matter lesions with reversible restricted diffusion supported the hypothesis of reversible vasospasm induced by the cyclosporin.

Thoracocervical dorsal dermal sinus associated with multiple vertebral body anomalies

Congenital dermal sinus is a type of closed spinal dysraphism. Cervical and thoracic regions are the rare sites for dorsal dermal sinuses. Dermal sinuses are frequently associated with dermoid or epidermoid tumor and osseous abnormalities such as bifid spinous process. The association of dorsal dermal sinuses with vertebral body anomalies is very rare. We present MR imaging features of a case of thoracocervical dorsal dermal sinus associated with multiple vertebral body anomalies.

Recent experience with Moyamoya disease in Turkey.

Abstract. A series of moyamoya patients is presented. Angiographic findings, outcome of revascularization surgery and a young case with moyamoya disease and hyperphosphatemia are reported. Thirteen patients (6 males and 7 females; age range 2–50 years) were included in the study group. Findings of the patients at presentation were intracranial haemorrhage in two adult cases and sequelae of cerebral ischemia in the rest of the group. One young girl had hyperphosphataemia. Angiography showed distal internal carotid or proximal anterior and middle cerebral artery stenosis, unique collaterals, microaneurysm of the posterior lateral choroidal artery and flow-related changes in the posterior circulation. In 3 patients, encephalo-duro-arterio-synangiosis (EDAS) and burrholes were performed at surgery. Follow-up angiograms of these patients showed revascularization. Moyamoya, a rare but potentially devastating disease, must be addressed as a cause of haemorrhagic and ischaemic cerebral events.

Imaging in tuberculosis of the skull and skull-base: case report

Abstract.We report a 19-year-old girl, who presented with headache and tonic/clonic seizures. Imaging revealed a lytic parietal skull lesion with an adjacent epidural mass, masses in the right parietal lobe and a posterior skull-base mass. The diagnosis of tuberculosis was made after resection of the extradural mass and later verified with culture of Mycobacterium tuberculosis. The parenchymal and skull-base lesions resolved following antituberculous treatment. We present CT, scintigraphic, angiographic and MRI findings.

An unusual complication of stapes surgery: profuse bleeding from the anteriorly located sigmoid sinus

Major bleeding during stapes surgery is a rare condition. The anterior course of the sigmoid sinus is comparatively common in contracted mastoid bones, but rare in good pneumatized temporal bones. We report a case of an unusual anterior course of the vertical segment of the sigmoid sinus, which led to profuse bleeding during a stapedotomy operation. The 34-year-old female patient presented with conductive-type hearing loss in the right ear. During the operation, the unintentional sliding movement of a blunt curette caused injury to the anteriorly positioned sigmoid sinus, which was separated from the posterior wall of the external auditory canal by an extremely thin shell of bone. Profuse bleeding from the sigmoid sinus was controlled by pushing the middle part of the oxidised regenerated cellulose inside the lumen, without compromising the sinus flow. After bleeding was restrained, the stapedotomy operation was completed successfully. During the 1-year follow-up, there was neither an air-bone gap nor a sensorineural hearing loss in pure tone audiogram.

Complication of Subclavian Vein Catheterization: Treatment with Endovascular Coil Embolization

Editor: We describe a case of internal mammary artery pseudoaneurysm as a complication of the insertion of a hemodialysis catheter into the subclavian vein and subsequent endovascular treatment. To our knowledge, this complication has not been previously reported. A 23-year-old man with a 10-year history of HenochSchonlein nephritis underwent renal transplantation due to end-stage renal disease 2 years prior to presentation. In June 1997, because of chronic rejection, hemodialysis was restarted with the placement of a left subclavian catheter. Three weeks after the placement, the patient was readmitted to the hospital with left shoulder pain, shortness of breath, fever, cough, and hemoptysis. Laboratory test revealed leukocytosis (white blood cell count, 26,000/mm3 [26 x 1O3IpL]) and increased sedimentation rate. Plain chest radiographs showed dense consolidation in left upper lung zone, diffuse acinar pattern in the middle and lower zones, and left pleural effusion. Computed tomography (CT) revealed a mass in eurysm was suspected and the patient was referred for arteriography to search for the origin. A selective left internal mammary arteriogram confirmed this finding (Figure, part b). A total of two 0.018-inch-diameter complex helical platinum microcoils (Target Therapeutics, Fremont, CA) were deposited. The pseudoaneurysm occluded after coil deployment with preserved patency of distal portion of the artery (Figure, part c) . The pa-