Yuichi Kamisaki

Intracranial dural arteriovenous fistula with retrograde cortical venous drainage: use of susceptibility-weighted imaging in combination with dynamic susceptibility contrast imaging.

BACKGROUND AND PURPOSE: SWI is a new MR imaging method that maximizes sensitivity to magnetic susceptibility effects with phase information for visualizing small cerebral veins. The purpose of this study was to report the use of SWI in combination with DSC in examining related RCVD in patients with intracranial DAVFs. MATERIALS AND METHODS: Ten patients with angiographically confirmed DAVFs with RCVD underwent conventional MR imaging, SWI, and DSC. The ability of SWI to depict dilated cerebral veins was evaluated and then compared with DSC. The hemispheres of patients with DAVFs were grouped into affected (with RCVD) or nonaffected (without RCVD) categories by angiography. Four patients had bilaterally affected hemispheres. A total of 14 affected hemispheres in patients with DAVFs with RCVD were evaluated. RESULTS: SWI showed dilated cerebral veins on the surface of the brain in all (100%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 9 (64%). T2-weighted imaging showed prominent flow-voids on the surface of the brain in 10 (71%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 5 (36%). DSC showed increased cerebral blood volume in all of the 14 affected hemispheres. The SWI findings regarding dilated veins on the surface of the brain corresponded well with the areas of increased cerebral blood volume. CONCLUSIONS: SWI in combination with DSC could be used to characterize the presence of RCVD in patients with DAVFs.

Dural arteriovenous fistula involving the transverse sigmoid sinus after treatment: assessment with magnetic resonance digital subtraction angiography

IntroductionThe purpose of this study was to evaluate the utility of magnetic resonance digital subtraction angiography (MRDSA) in showing the presence or absence of retrograde venous drainage (RVD) in patients with intracranial dural arteriovenous fistula (DAVF) involving the transverse sigmoid sinus (TSS) after treatment.MethodsOf 16 patients with DAVF involving the TSS, 13 underwent digital subtraction angiography (DSA) and MRDSA before and after treatment, and 3 underwent DSA before treatment and DSA and MRDSA after treatment. Five patients underwent these procedures twice after treatment. A total of 21 examinations after treatment were evaluated retrospectively. The presence or absence of DAVF and RVD was decided on the basis of the DSA findings. Two neuroradiologists reviewed the MRDSA findings concerning the presence or absence of DAVF and RVD.ResultsDSA showed residual DAVF in 9 and residual RVD in 5 of 21 examinations. MRDSA revealed residual DAVF in 8 of 21 examinations. MRDSA did not show residual DAVF in one examination because of a very small (low-flow) residual DAVF without RVD. MRDSA identified residual RVD in 5 of 21 examinations. MRDSA was completely consistent with DSA concerning the presence or absence of residual RVD.ConclusionMRDSA could evaluate the presence or absence of RVD in patients with DAVF involving TSS after treatment. MRDSA may give reliable information as to whether patients with DAVF involving the TSS should undergo additional DSA after treatment.

FDG-PET imaging in duodenal cancer

F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) imaging is a useful modality in the detection of various tumors, including colon cancer and gastric cancer. We evaluated a patient with duodenal cancer with multiple metastases including brain metastases using FDG-PET imaging. It revealed multiple tumor uptake in the brain, clavicular fossa, mediastinum, right adrenal gland and duodenum. These results suggest that FDG-PET imaging may be useful in detecting the primary and metastatic lesions of duodenal adenocarcinoma.

Contralateral cerebellar activation in frontal lobe epilepsy detected by ictal Tc-99m HMPAO brain SPECT.

A 65-year-old woman with Alzheimer dementia type with status epilepticus had an electroencephalogram, which showed an epileptic focus in the right frontal area. MRI showed no pathologic findings except for mild brain atrophy. Tc-99m HMPAO brain SPECT imaging during the ictal phase showed a marked increase of regional cerebral blood flow in the right dorsolateral frontal lobe, and ipsilateral basal ganglia and thalamus, in which regional cerebral blood flow was increased by 23-83% as compared with the left side. Interestingly, contralateral cerebellar activation was observed, where regional cerebral blood flow was increased by 23% as compared with the right side.

Flow-sensitive alternating inversion recovery (fair) imaging for retrograde cortical venous drainage related to intracranial dural arteriovenous fistula

IntroductionTo evaluate the hypothesis that flow-sensitive alternating inversion recovery (FAIR) magnetic resonance (MR) imaging can detect retrograde cortical venous drainage (RCVD) in patients with intracranial dural arteriovenous fistula (DAVF).MethodsSeven patients with angiographically confirmed DAVF with RCVD and two DAVF patients without RCVD underwent examinations with conventional MR imaging and FAIR, five of these seven patients with RCVD also underwent examination with dynamic susceptibility contrast (DSC) MR imaging. The ability of FAIR to depict prominent cerebral veins was evaluated, and FAIR was compared with the relative cerebral blood volume (rCBV) maps created with DSC.ResultsIn all DAVF patients with RCVD, FAIR clearly showed prominent veins on the surface of the brain in affected hemisphere, and FAIR corresponded well with the areas of increased rCBV. In all DAVF patients without RCVD, FAIR showed no prominent veins.ConclusionFAIR can detect RCVD in patients with DAVF.

F-18 FDG-PET imaging in adult T-cell leukemia lymphoma.

Adult T-cell leukemia lymphoma is extremely rare. We report a case of adult T-cell leukemia lymphoma involving lymph nodes and the liver. F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) imaging is a useful modality in detecting various tumors, including malignant lymphoma. We evaluated a patient with adult T-cell leukemia lymphoma using F-18 FDG PET imaging, which detected abnormal increased uptake in the left submandibular area, neck, clavicular area, axilla, mediastinum, liver, abdomen, and groin. The standardized uptake value of the highest FDG uptake was 20.5.

Qualitative evaluation of chronic diffuse liver disease by STIR MRI.

Objective The purpose of our study was to characterize the relationship between signal intensity on STIR MRI, histology, and liver function. Materials and Methods MRI was performed in 39 patients with chronic liver diseases [chronic persistent hepatitis (CPH), chronic active hepatitis (CAH), liver cirrhosis (LC)] and 11 patients without liver dysfunction (normal). Results On STIR images, very low signal intensities compared with those of the spleen were seen in all 11 normal livers (100%), and brighter intensities were seen in chronic diffuse liver diseases (10 patients with CPH, 11 patients with CAH, and 18 patients with LC) (100%). The higher the signal grade on STIR images (moderate, marked), the more advanced was the chronic diffuse liver disease (p < 0.02). The levels of serum glutamic–oxaloacetic and glutamic-pyruvic transaminase increased in parallel with increasing signal intensity on STIR images (both p < 0.01). Conclusion We found that the signal intensity of liver on STIR images appeared to be associated with the degree of histologic and/or clinical severity in patients with chronic liver disease.

I-123 MIBG imaging of metastatic carcinoid tumor from the rectum.

I-131 MIBG, a specific radiopharmaceutical agent for scintigraphic imaging and treatment of pheochromocytoma and neuroblastoma may be useful for detection of apudomas. Scintigraphy with I-123 radiolabeled MIBG was performed in a patient with metastatic carcinoid tumor from the rectum. I-123 MIBG scintigraphic findings showed multiple areas of abnormal tumor uptake of hepatic and bone metastases from the rectal carcinoid. Bone scintigraphy demonstrated multiple metastatic lesions. Computed tomography revealed multiple solid tumors of the liver. This report describes accumulation of I-123 MIBG in the liver and bone metastases from the rectal carcinoid. Radioiodine MIBG scintigraphy may be useful for detecting metastatic lesions, for evaluating postoperative recurrence, and also for the treatment of the carcinoid tumor.

The value of combined99mTc-Sn-colloid and99mTc-RBC scintigraphy in the evaluation of a wandering spleen

Wandering spleen is the term commonly applied to splenic hypermobility that results from laxity or maldevelopment of its suspensory ligaments. It comes to medical attention usually as an abdominal mass, or when the spleen undergoes torsion. Diagnosis on clinical grounds alone is rarely made, and ultrasonography, CT and MRI findings have no specific characteristics for this condition.99mTc-labeled colloid taken up by the spleen may provide a specific diagnosis. We report a case of wandering spleen, in which the preoperative diagnosis was made on the basis of sequential liverspleen scintigraphy with99mTc-Sn-colloid and blood-pool scintigraphy with99mTc-RBC. This is a rare case, in which hypermobility was assessed by sequential99mTc-Sn-colloid scintigraphy, and to our knowledge, is the first case in which99mTc-RBC scintigraphy provided useful information on splenic blood volume and its location.

A case of renal pelvic tumor visualized by18F-FDG-PET imaging

Abstract18F fluorodeoxyglucose positron emission tomography (18F-FDG PET) imaging is a useful modality in detecting various tumors, including renal cell carcinoma. We evaluated a patient with renal pelvic tumor (transitional cell carcinoma) with multiple metastases using18F-FDG PET imaging and detected abnormal increased uptake of a right renal pelvic tumor extending to the renal cortex with liver metastasis and paraaortic lymph node metastases. These results suggest that18F-FDG PET imaging may be useful in detecting primary and metastatic lesions of renal pelvic tumor (transitional cell carcinoma).