Mustafa Kemal Demir

Value of Dynamic Contrast-Enhanced MRI and Correlation with Tumor Angiogenesis in Bladder Cancer

OBJECTIVE The aim of this study was to investigate dynamic contrast-enhanced MRI (DCE-MRI) for the noninvasive measurement of bladder cancer angiogenesis by correlation with microvessel density, histologic grade, and tumor staging, and to predict the outcome of local recurrence. MATERIALS AND METHODS Twenty-four patients with bladder cancer were examined using DCE-MRI. Hemodynamic parameters obtained by DCE-MRI included peak time enhancement in the first minute (E(max/1)) after contrast administration, second minute (E(max/2)), third minute (E(max/3)), fourth minute (E(max/4)), and fifth minute (E(max/5)), and the steepest slope. Microvessel density was identified by immunostaining of endothelial cells using FVIII-related antigen. The Mann-Whitney U test, multivariate discriminant analysis, Spearmans correlation coefficient, and analysis of variance were used for statistical analysis. RESULTS Correlation was seen between DCE-MRI parameters (E(max/1) and steepest slope) and microvessel density (p < 0.05). E(max/1) and steepest slope were found to have a statistically significant correlation with histologic grade (p < 0.05 and p < 0.01, respectively). A significant difference was seen between groups of patients with and without local recurrence with regard to two of the DCE-MRI parameters (p < 0.05 for E(max/1) and E(max/2)). CONCLUSION The contrast enhancement patterns on DCE-MRI are influenced by tumor angiogenesis, as reflected by elevated microvessel density expression. Therefore, they are valuable indicators for assessing tumor angiogenic activity and tumor neovascularization in bladder cancers.

Hepatic pseudolesion around the falciform ligament: prevalence, aberrant venous supply, and fatty infiltration evaluated by multidetector computed tomography and magnetic resonance imaging.

Purpose: The aim of this study was to determine the prevalence and aberrant venous supply (inferior veins of Sappey) of hypoattenuating hepatic pseudolesions seen around the falciform ligament on portal-dominant phase multidetector computed tomography (MDCT) and the frequency of fatty infiltration of these pseudolesions on chemical-shift magnetic resonance imaging. Materials and Methods: Portal-dominant phase abdominal MDCT examinations of 728 patients were evaluated for the presence of a pseudolesion around the falciform ligament, and those with a presumed pseudolesion underwent chemical-shift magnetic resonance imaging to detect the fatty infiltration. Reconstructed MDCT images were investigated for the presence of an inferior vein of Sappey, and 30 patients without a pseudolesion were evaluated as a control group. Results: A total of 160 pseudolesions were detected around the falciform ligament in 146 (20%) patients. The longest diameter of the pseudolesions was in the craniocaudal direction in most patients (61%). An inferior vein of Sappey supplying these pseudolesions was depicted in 40 (27%) patients, and it was highly significant (P = 0.001) compared with the controls for the presence of a pseudolesion around the falciform ligament. Fatty infiltration was found in 47 (29%) patients. Conclusions: Hepatic pseudolesions around the falciform ligament are frequently encountered on portal-dominant phase MDCT images. Detection of craniocaudal extension, inferior veins of Sappey, and fatty infiltration of these pseudolesions, which were firstly described in this article, with the largest subject group based on cross-sectional imaging, might be valuable in excluding true tumors.

Case 142: Susac Syndrome

History A 21 year-old woman presented with decreased visual acuity in her right eye. At admission, visual acuity was 20/70 in her right eye and 20/20 in her left eye. For the previous 20 days, this patient had also experienced mi-grainelike headache, vertigo, tinnitus, and vomiting. She had no uve iti s or keratoconjunctivitis. Her medical history did not include any other pertinent findings. A week after admission, this patient developed weakness on the left side of her body, partial hearing loss in her left ear, and visual impairment in her left eye. Otoscopic findings were unremarkable. Audiologic evaluation revealed sensorineural low-frequency hearing loss in her left ear and normal hearing in her right ear. The results of laboratory studies, including autoimmune panels, were normal. Magnetic resonance (MR) imaging of the brain was performed.

Computed tomographic and magnetic resonance imaging findings of asymptomatic intra-abdominal gastrointestinal system lipomas.

Lipomas are common benign mesenchymal neoplasms documented in literature. This study aimed to describe the computed tomographic (CT) and magnetic resonance imaging (MRI) findings of gastrointestinal system lipomas, all of which are incidentally found in routine abdominal imaging studies. Lipomas were depicted as homogeneous, nonenhancing, well-marginated lesions consistent with adipose tissue on CT and MRI. The density measurements on CT images consistent with fat are virtually diagnostic. Lipomas can incidentally be found and should be considered in the differential diagnosis of soft tissue gastrointestinal system-related masses. Computed tomographic or MRI examinations can correctly diagnose a lipoma nonoperatively, thereby allowing better treatment planning.

Case 134: Primary Leptomeningeal Melanomatosis

A 32-year-old man was admitted to the hospital with headache, vomiting, and complex partial seizures. Thirty weeks earlier, he had undergone ventriculoperitoneal (VP) shunt placement to treat hydrocephalus that had been diagnosed with cranial magnetic resonance (MR) imaging. Hydrocephalus was the only abnormality present. During the 30-week interval, two consecutive whole-spine MR examinations were performed 8 weeks apart at different institutions. Neurologic examination revealed mild decreased consciousness, papilledema, and deficits in cranial nerves III, IV, V, and VII. The patient was afebrile, and physical examination revealed no other abnormalities. The findings of laboratory tests, including extensive cerebrospinal fluid studies, were unremarkable. Cranial computed tomography (CT) was performed.

Detection and quantification of the parenchymal abnormalities in emphysema using pulmo-CT.

We aimed to determine the degree and extent of parenchymal abnormalities on pulmo-CT in patients with emphysema. The study group consisted of 29 patients (18 male, 11 female; mean age 57.9+/-13). The diagnosis was based on clinical symptoms, pulmonary function tests (PFT) values, and chest CT findings. All of the patients CT scans were obtained during suspended deep inspiration from the apices to the costophrenic angles. The mean lung attenuation (MLD) and parenchymal abnormalities related to emphysema were quantitatively calculated with tables, histograms and graphics at the whole lung. The lung density measurements revealed a mean density of -898.48+/-51.37 HU in patients with emphysema and -825.1+/-25.5 HU in control group. In addition, mean percentage of subthreshold attenuation values was found as 12.03+/-15.75 and 1.07+/-0.83 in patients with emphysema and control group, respectively. Compared with control group, the patients with emphysema had a significantly lower inspiratory MLD (p<0.05). Additionally, statistically significant correlations were seen between the MLD and percentage of subthreshold values (r=0.44, p<0.05). In contrast, there was poor correlation between PFT measurements and the subthreshold values. In conclusion, pulmo-CT is a quick, simple method for quantitative confirmation of the presence of parenchymal abnormalities of lung as mosaic attenuation and should be used in combination with other radiological methods and PFT as it gives additional information to routine examinations in patients with emphysema.

Bilateral extra-adrenal perirenal myelolipomas: CT features.

Myelolipomas are rare benign tumours composed of adipose tissue and haematopoietic cells that are typically found in adrenal glands but have also appeared in extra-adrenal sites. Distinguishing between extra-adrenal myelolipomas and malignant tumours, such as liposarcomas, is crucial to avoid an invasive procedure. To this end, we present a comprehensive report of the CT imaging characteristics of a pathologically proven bilateral extra-adrenal perirenal myelolipoma.

Case 131: Proteus Syndrome

A 21-year-old woman was referred for cerebral and craniofacial magnetic resonance (MR) imaging and computed tomographic (CT) examination because of the asymmetric appearance of the right side of her face and the consideration of facial paralysis. Neurologic examination revealed that the patient did not have facial nerve palsy and that her appearance was caused by facial asymmetry. Laboratory studies revealed no abnormality. There was no family history of congenital anomaly. Physical examination revealed an asymmetric soft-tissue prominence on the posterior part of her chest and abdomen. There was a history of a progressive course of asymmetry of the hands and feet and a hyperpigmented epidermal nevus on the left dorsal aspect of the trunk, (Asymmetric overgrowth of the patients hands and feet was stabilized after puberty.) Radiographs of the pelvis, vertebrae. and extremities (not shown) were normal except for mild scoliosis. Unenhanced CT of the chest, abdomen, and pelvis was performed.

Digital subtraction angiography of a persistent trigeminal artery variant.

Persistent trigeminal artery variants are described as cerebellar arteries that directly originate from the precavernous segment of the internal carotid artery. This has been observed in 0.18% of cerebral catheter angiograms. On the other hand, a persistent trigeminal artery variant feeding both the anterior inferior cerebellar artery and the posterior inferior cerebellar artery territory is very rare. We present this uncommon anomalous artery along with digital subtraction angiography findings and discuss its clinical significance in light of the literature.Persistent trigeminal artery variants are described as cerebellar arteries that directly originate from the precavernous segment of the internal carotid artery. This has been observed in 0.18% of cerebral catheter angiograms. On the other hand, a persistent trigeminal artery variant feeding both the anterior inferior cerebellar artery and the posterior inferior cerebellar artery territory is very rare. We present this uncommon anomalous artery along with digital subtraction angiography findings and discuss its clinical significance in light of the literature.

Posterior epidural migration of lumbar disc fragment as an unusual ring-enhancing mass.

A 60-year-old man was admitted to the hospital because of 2-month history of low back pain and difficulty in walking. Bladder and bowel functions were normal. The clinical history was unremarkable. On physical examination, both lower limbs showed muscular weakness with increased muscle tone, especially on the right side. Sensation was intact in all dermatomes, and reflexes were normal. Laboratory tests revealed normal findings. Magnetic resonance imaging showed a wellcircumscribed smoothly marginated solid mass within the posterior epidural space at L2–L3, which compressed the dura. Signal intensity of the mass was similar to that of the intervertebral disc on all sequences (Fig. 1). The lesion revealed an intense rim enhancement on fat-saturated contrastenhanced magnetic resonance images (Fig. 1). There was no calcification in the epidural mass lesion on computed tomography scan (Fig. 2). Decompressive L2 laminectomy was