İlhan Erden

Aneurysms of the portal venous system: Gray-scale and color doppler ultrasonographic findings with CT and mri correlation

Two cases of incidentally detected aneurysms involving the portal venous system are described with emphasis on gray-scale and color Doppler ultrasonographic (US) findings. Appearing on US as anechoic masses showing direct luminal continuity with the right portal vein and superior mesenteric vein, the lesions displayed spectral findings characteristic of portal venous system on color Doppler US. Dynamic helical computed tomography (CT) demonstrated simultaneous enhancement with the portal system, while the aneurysms were hypointense owing to flow void on T1-weighted spin-echo magnetic resonance (MR) images.

CT and MRI in tuberculous sternal osteomyelitis A case report

We report a 58-year-old male patient presenting with a 1-year history of presternal swelling and pain. Plain radiography revealed increased soft tissue density anterior to the body of the sternum, which showed cortical sclerosis. Computed tomography (CT) demonstrated ring-enhancing hypodense soft tissue masses surrounding the sternum, whose anterior and posterior cortices were markedly thickened. On three-phase technetium bone scintigraphy, the left side of the sternum showed increased radiotracer uptake and the central part of the bone was photopenic. The bone marrow of the sternum and peristernal soft tissue lesions were hypo- and hyperintense on T1- and T2-weighted magnetic resonance (MR) images, respectively, and showed marked enhancement postgadolinium. Treatment included both surgical intervention and medical therapy.

Frontal sinus mucocele A rare complication of craniofacial fibrous dysplasia

We present plain radiographic, computed tomographic and magnetic resonance imaging (MRI) findings in a 25-year-old female patient with craniofacial fibrous dysplasia (FD). Although FD has a tendency to involve craniofacial bones in a unilateral fashion, the involvement was bilateral and extensive in this case. An additional feature was the presence of a frontal sinus mucocele, presumably due to the involvement of the sinus recess by the dysplastic process. This complication of the craniofacial FD has been reported very infrequently in the literature.

Role of magnetic resonance imaging in children with voiding dysfunction: retrospective analysis of 81 patients

OBJECTIVES To investigate the role of magnetic resonance imaging (MRI) in children with voiding dysfunction and a normal neuro-orthopedic assessment. The differential diagnosis of neurogenic and non-neurogenic voiding dysfunction, particularly in children with occult neurogenic pathologic findings without a clinically demonstrable neurologic defect, is a commonly encountered problem. METHODS Eighty-one children with voiding dysfunction, including a history of diurnal incontinence, frequency, urgency, urge incontinence, incomplete bladder emptying, recurrent urinary tract infection, and persistent vesicoureteral reflux, constituted our study group. A detailed neuro-orthopedic evaluation was performed in all patients. The urologic evaluation consisted of a detailed history (including bowel function disturbances), renal sonography or excretory urography, spinal x-ray, urinalysis and culture, voiding cystourethrography, and multichannel water cystometry. In all cases, lumbosacral spinal axial and sagittal T1- and T2-weighted MRI performed with a 1.5-Tesla surface coil was reviewed by one neuroradiologist. RESULTS MRI revealed pathologic findings in 17 (38.6%) of 44 patients who had voiding dysfunction and a normal neuro-orthopedic assessment. All these patients underwent early surgical intervention in our pediatric neurosurgery department. In the postoperative period, objective and/or subjective improvement in voiding symptoms within short (6 months) and long (14 months) periods was observed in 8 (47.0%) and 5 (29.4%) patients, respectively. Ten (58.8%) of those 17 patients had a history of voiding dysfunction refractory to conservative management. CONCLUSIONS Our results revealed that MRI of the lower spinal cord is a valuable tool in the diagnosis of occult spinal cord disorders, especially in patients with voiding dysfunction refractory to conservative management strategies and normal neurologic and orthopedic assessments.

Portal venous system Evaluation with contrast-enhanced 3D MR portography

The purpose of this study is to compare contrast-enhanced three-dimensional (3D) magnetic resonance (MR) portograms to Doppler sonography in detection of portal venous abnormalities. Thirty-five consecutive patients, who were suspected of having portal venous system abnormalities, were examined with MR portography and Doppler sonography. Vascular abnormalities were identified in 27 of 35 patients. There was statistically significant agreement between the results of MR portography and Doppler sonography. The major limitation of contrast-enhanced 3D MR portography was its inability to provide objective hemodynamic data regarding flow direction and flow pattern.

Gadolinium-enhanced three-dimensional MR angiography in jugular phlebectasia and aneurysm.

True jugular vein aneurysms and phlebectasias are very rare abnormalities, which are usually discovered in children. Though their ultrasonographic features have been well described, magnetic resonance angiographic appearance of these lesions has not been reported in the radiology literature. We describe gadolinium-enhanced MR angiographic findings in two patients with internal jugular vein phlebectasia and one patient with anterior jugular vein aneurysm. The jugular venous system and its abnormalities were successfully depicted in the coronal plane, much like the images of coronal angiography.

Trigeminal nerve involvement in T-cell acute lymphoblastic leukemia: value of MR imaging

A 30-year-old male with T-cell acute lymphoblastic leukemia presented with facial numbness. Neurological examination revealed paresthesia of the left trigeminal nerve. Cerebrospinal fluid (CSF) cytology showed no atypical cells. Gadolinium-enhanced magnetic resonance (MR) imaging demonstrated enlargement and enhancement of intracranial portions of the left trigeminal nerve. The abnormal MR imaging findings almost completely resolved after the chemotherapy. Gadolinium-enhanced MR imaging is not only a useful procedure for the early diagnosis of cranial nerve invasion by leukemia but it might be helpful to follow the changes after the treatment.

Hepatic outflow obstruction: enhancement patterns of the liver on MR angiography

Our purpose was to present the enhancement patterns of the liver on MR angiography in patients with hepatic outflow obstruction. Twenty-three patients with Budd-Chiari syndrome (4 in acute stage and 19 in chronic stage of the disease) were examined with 3D contrast-enhanced MR angiography. During early and late portal venous phase of MR angiography the pattern of parenchymal enhancement was assessed on source images. The enhancement patterns were evaluated under 4 groups as following: (a) central (b) peripheral (c) patchy and (d) homogeneous enhancement. The morphologic changes in the liver (lobar hypertrophy or atrophy, hepatic surface irregularities) were also recorded. In the acute stage global liver enlargement (75%) with caudate hypertrophy (100%) and central enhancement of the liver (75%) were suggestive findings of the hepatic outflow obstruction. The left lobe hypertrophy (53%) associated with the caudate lobe hypertrophy (72%) and irregular surface (26%) were predominant in the chronic stage of the disease. The enhancement patterns seen in chronic disease were variable and reflected the persistent stasis of the portal blood flow (patchy enhancement in 32% of the patients) or the altered hemodynamics of the liver due to the development of subcapsular collaterals (peripheral enhancement in 21% of the patients). Homogeneous enhancement of the liver in Budd-Chiari syndrome may indicate the chronicity of the outflow obstruction (37%) and shows a more stable hepatic perfusion that occurs after the formation of intra and extrahepatic collateral veins. The morphological and perfusional features on multiphase contrast-enhanced MR angiography are valuable in understanding the effects of the hepatic outflow obstruction on the liver parenchyma.

Identification and removal of an epileptogenic lesion using Ictal-EEG, functional-neuronavigation and electrocorticography

PURPOSE Cases with intractable epilepsy may present with multiple lesions in their brains. Ictal-EEG carries a great value in identification of the primary epileptogenic source. On the other hand, removal of low-grade tumors located around the eloquent cortex may be risky with conventional techniques. Functional-neuronavigation (f-NN) is the integration of functional magnetic resonance imaging and stereotactic technologies; and provides interactive data regarding localization of the motor cortex. This report presents a case with dysembryoplastic neuroepithelial tumor (DNET), which was removed using f-NN and electrocorticography (ECoG) techniques. METHODS A 19-year-old patient with intractable complex partial and secondary generalized seizures is presented. MRI revealed a low-grade tumor located in right parietal region just behind the motor cortex, and a contralateral temporal arachnoid cyst. Ictal-EEG demonstrated the right parietal origin of the seizures. The patient underwent a right parietal craniotomy and tumor excision using f-NN and ECoG techniques intraoperatively. ECoG findings correlated with epileptogenicity of the parietal lesion. RESULTS Postoperative course was uneventful. No postoperative deficit was observed. The patient was seizure free in eight months follow-up. Pathological examination reported the lesion as DNET. CONCLUSIONS Ictal-EEG has a very important role in identification of the epileptogenic focus in cases with multiple brain lesions. Preservation of the functional cortex is the most prominent aim during lesional surgery of epilepsy. Intraoperative mapping using f-NN and ECoG supports the orientation of the neurosurgeon to the functional and epileptogenic cortical areas; and thus, increase the safety and efficacy of surgical procedures.