Taner Üçöz

The added value of the apparent diffusion coefficient calculation to magnetic resonance imaging in the differentiation and grading of malignant brain tumors.

Objective: ADC calculation can improve the diagnostic efficacy of MR imaging in brain tumor grading and differentiation. Methods: Apparent diffusion coefficient (ADC) values and ratios of 33 low-grade (23 astrocytomas, 10 oligodendrogliomas) and 40 high-grade (25 metastases and 15 high-grade astrocytomas) malignant tumors were prospectively evaluated. Results: Tumoral ADC values (r = −0.738, P < 0.000) and ratios (r = −0.746, P < 0.000) were well correlated with higher degree of malignancy and quite effective in grading of malignant brain tumors (P < 0.000). By using cutoff values of 0.99 for tumoral ADC value and 1.22 for normalized ADC ratio, the sensitivity of MR imaging could be increased from 72.22% to 93.75% and 90.63%, the specificity from 81.08% to 92.68% and 90.24%, PPV from 78.79% to 90.91% and 87.88%, and NPV from 75.00% to 95.00% and 92.50%, respectively. Conclusion: ADC calculation was quite effective in grading of malignant brain tumors but not in differentiation of them and added more information to conventional contrast-enhanced MR imaging.

Median arcuate ligament syndrome: multidetector computed tomography findings.

Objective: We aimed to describe the clinical and multidetector computed tomography (MDCT) angiography findings of celiac, mesenteric, and renal artery entrapment by the median arcuate ligament. Materials and Methods: Patients (n = 453) who underwent MDCT abdominal aorta angiography in a period of 3 years were retrospectively reviewed for vascular compression by median arcuate ligament known as median arcuate ligament syndrome. The MDCT examinations were performed with 16-slice (n = 292) and 64-slice scanners (n = 161). The median arcuate ligament itself and adjacent vascular branches of abdominal aorta were assessed for compression by 2 different radiologists who are experienced on MDCT angiography more than 3 years. Both axial, multiplanar reformatted images and 3-dimensional angiographies were used for interpretation. Results: Twelve patients were found to have clinically significant vessel entrapments by median arcuate ligament; 6 of them with celiac artery, 4 of them with renal artery, and 2 of them with both celiac and mesenteric artery involvement. Patients with celiac and mesenteric vessel entrapments presented with epigastric pain. All patients with renal artery entrapment had resistant hypertension. The MDCT showed the proximal narrowing caused by compression of median arcuate ligament. The proximal portions of renal arteries pulled down and in toward the aorta, with mild to moderate narrowing. Conclusions: The MDCT exanimation with multiplanar images and 3-dimensional angiography is a noninvasive imaging technique that can be used with high accuracy in the diagnosis of median arcuate ligament syndrome.

Value of magnetic resonance imaging in the depiction of intravenous leiomyomatosis extending to the heart.

Intravenous leiomyomatosis is a seldom neoplasia characterized by invasion of venous channels by a benign smooth muscle tumor originating either from a uterine myoma or from vessel wall. Extension to the heart may cause mechanical obstruction and is frequently misdiagnosed as a right-atrial myxoma. We present a case of recurrent intravenous leiomyomatosis with previous hysterectomy because of uterine leiomyoma which have different magnetic resonance characteristics than that of the former reports.

Diagnostic value of MRI in tuberculous meningitis

In this study 15 patients with clinical findings and positive cerebrospinal fluid analyses for tuberculous meningitis were evaluated with magnetic resonance imaging (MRI). Tuberculous meningitis was diagnosed in 11 cases when thick meningeal enhancement was present after intravenous injection of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) in T1-weighted images. Intra-axial tuberculomas were present in 8 patients, 2 of whom had intra-axial tuberculomas without MRI evidence of meningitis. Tuberculomas showed ring or nodular enhancement in postcontrast T1-weighted images, but the most significant MR feature of intraparenchymal tuberculomas was the hypointense appearance of the lesions on T2-weighted images.

Preoperative evaluation of the congenital aural atresia on computed tomography; an analysis of the severity of the deformity of the middle ear and mastoid

OBJECTIVE To compare the development of temporal bone in normal and atretic ears and to assess some radiological landmarks that could be important in the hearing restoration interventions in such patients. MATERIAL AND METHODS Thirty-five patients with 40 atretic external ears were evaluated with temporal bone CT and compared to a control group of 40 normal ears retrospectively. Using comparable slice levels in all patients, the course and the caliper of the facial canal, the surface area of the incus and malleus, the level of mastoid aeration, the location and anteroposterior diameters of the jugular bulb and sigmoid sinus, the direction and the caliber of the tympanic bony part of the Eustachian tube, area of the middle ear cavity, distance from facial nerve to incudomalleolar joint, to the vestibule and to the jugular bulb were included in the assessment. Non-parametric and parametric statistical tests were used for comparison. RESULTS In atretic ears middle ear sectional area was found to be smaller at the equivalent plane as compared to control subjects (mean area index: 19.3mm(2) versus 47.4mm(2)). Mastoid aeration was low in general and the ossicles in the atretic ears were hypoplastic (mean ossicular sectional area: 8.3mm(2) versus 11 mm(2)). The distance from the jugular bulb to the facial nerve was significantly lower (mean: 6.2mm versus 6.8mm) (p<0.05) in the atretic ears. Facial canal caliber, distance from the facial canal to the incudomalleolar joint and distance from the facial canal to the vestibule in the atretic ears (means: 1.49, 2.93 and 1.82, respectively) did not show statistically significant difference from the control subjects (means: 1.44, 2.91 and 1.83, respectively) (p>0.05 for all). CONCLUSION External ear atresia is significantly associated with middle ear and mastoid abnormalities. The ossicles were underdeveloped which always have to be considered during reconstructive surgery. Radiologically, in the atretic ears anterior-posterior length of the temporal bone was more influenced as compared to superior-inferior portion, which justifies abnormal route of the facial nerve canal. However, there is no abnormality in the development of the facial nerve as the caliper is similar to the control subjects.

Multiple globoid meningiomas associated with craniomandibular fibrous dysplasia: Case report

A 20-year-old male with craniomandibular deformity and almost total visual loss of the right eye due to bilateral optic atrophy underwent cerebral nonenhanced computed tomography (NECT) examinations. He had multiple sphenoidal-temporoparietal meningiomas, with adjacent hyperostoses and distant calvarial hyperdense lesions, as well as sclerotic expansion of right mandibular condyle. History, clinical and imaging findings were suggestive of associated fibrous dysplasia (FD), which explained the visual loss due to optic nerve compression through sphenoidal optic foramens. Cranial and mandibular FD and concurrent multiple globoid meningiomas in this case may suggest a mutual influence, which may explain the etiopathogenesis of FD lesions and/or bone hyperdensities adjacent or distant to meningiomas.

Optic disc coloboma (the morning glory syndrome) and optic nerve coloboma associated with transsphenoidal meningoencephalocele

Abstract The association optic disc coloboma (the morning glory syndrome), optic nerve coloboma, and transsphenoidal meningoencephalocele is extremely rare. We describe an original case of optic disc coloboma in association with optic nerve coloboma, microphthalmos, optic nerve hypoplasia, and transsphenoidal meningoencephalocele. There were no midfacial anomalies (hypertelorism, broad nasal root, cleft lip, and cleft plate) and pituitary dysfunction. For patients who had optic disc-nerve coloboma without midfacial anomalies, neuroimaging should be prompted to look for transsphenoidal encephalocele/meningoencephalocele and other anomalies. We present demonstrative fundoscopic pictures, ultrasound and magnetic resonance imaging of this original case of a 7-year-old patient.

CT pneumoangiogram sign following cardiopulmonary resuscitation: detrimental cerebral air embolism or postmortal blood replacement with air?

Abstract Massive air in the cerebral vessels (pneumoangiogram) on postmortal computed tomography (CT) examination after cardiopulmonary resuscitation of a 10-year-old child with severe thoracic trauma is reported and possible mechanism of pneumoangiogram is discussed. The patient suffered from severe head and chest injury and was transported to hospital in a cardiopulmonary arrest state. Cardiopulmonary resuscitation was not successful and to find the cause of death, postmortal cranial CT and supine chest X-radiography were performed. Chest X-ray revealed almost total obliteration of left pulmonary aeration as well as pneumomediastinum and bilateral hydropneumothorax. On CT scans, diffuse air was seen in the carotid arteries, middle and anterior cerebral arteries, the vertebral arteries, and in the right sigmoid sinus. This pneumoangiogram sign is believed to be the end result of pumped pneumothorax–pneumomediastinum air which was sucked through the lacerated thoracic great vessels via cardiac massage, replacing the emptied cerebral vessel lumens previously depleted of blood through massive thoracic hemorrhage and has nothing to do with a death contributing detrimental cerebral air embolism.

Walker–Warburg syndrome variant

A Turkish patient with cobblestone lissencephaly and eye involvement without characteristic muscular changes for congenital muscular dystrophy died at the age of 3 months presented with neonatal apneic periods and generalized seizures. Serum creatine kinase level, electromyography, chromosome analysis and blood biochemistry were normal. Unilateral microphthalmia, retinal dysplasia and internal strabismus were the ocular findings. Magnetic resonance imaging clearly demonstrated the thickened, irregular, nearly agyric cobblestone cerebral cortex with underlying unmyelinated white matter, hydrocephalus, hypoplastic corpus callosum, brain stem and cerebellum with retrocerebellar cyst and posterior cephalocele.