Endovascular treatment of peripheral aneurysms of the posterior inferior cerebellar artery.

BACKGROUND AND PURPOSE: Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare, and pre-existing literature concerning their endovascular treatment is limited. The purpose of this study was to assess the etiology and clinical characteristics of peripheral PICA aneurysms and to evaluate the angiographic and clinical results of the patients who underwent endovascular treatment for a peripheral PICA aneurysm in a single center. MATERIALS AND METHODS: Twelve consecutive patients with 12 peripheral PICA aneurysms (10 ruptured) included in an internal data base were retrospectively reviewed. Posttreatment and follow-up angiograms were analyzed, and the clinical outcome was recorded. RESULTS: The etiology was dissection in 7 (58%) and unknown in 5 cases (42%). Three dissecting aneurysms reruptured before endovascular treatment, and another 3 demonstrated angiographic progress. Four aneurysms were treated by endosaccular coiling, 6 (all dissecting) by parent artery occlusion, and in 2 cases endovascular treatment failed. Angiographic outcome was complete aneurysm and/or parent artery occlusion in 9 cases and neck remnant in 1 case. One aneurysm needed retreatment at follow-up. One lethal procedural complication occurred, and transient ischemic symptoms appeared in 2 patients. The clinical outcome was good in 7 patients, whereas 3 patients, all poor clinical grade, died (1 for unrelated reasons). No rebleedings have occurred during the follow-up. CONCLUSION: In this series, most peripheral PICA aneurysms were secondary to arterial dissection. They were unstable with a high risk of rebleeding and a high mortality if not treated without delay. Endovascular treatment was effective in preventing rehemorrhage.

Magnetic resonance imaging and radiographic findings of seal finger.

PURPOSE: To describe the magnetic resonance imaging (MRI) and radiographic findings of five patients with seal finger. MATERIAL AND METHODS: The MR images and radiographs of five patients with seal finger were retrospectively evaluated. MRI was performed on four patients in the subacute phase, and follow-up imaging was done on one of them at 5 months. One patient had MRI only at a later stage 5 years after onset. Radiographs were taken three times in the subacute phase and once at a later stage. One patient had had seal finger in another finger previously. RESULTS: Short-tau inversion-recovery (STIR) sequence showed extensive subcutaneous soft tissue edema in all four patients in the subacute phase and tenosynovitis of the flexion tendons in two cases. Three patients had edema in 2-3 phalanges, and effusion in the distal interphalangeal (DIP) joint was seen in one case. At the later stage, no signal pathology in soft tissues or bones was seen in STIR images. In the subacute phase, radiographs showed digital soft-tissue swelling in three patients, and one patient had a narrowed DIP joint, periarticular osteoporosis, and a periosteal reaction. At the later stage, flexion contracture of the finger was seen. CONCLUSION: In addition to soft-tissue infection, seal finger causes bone marrow edema, tenosynovitis, and effusion in the interphalangeal joints visible as increased signal intensity in STIR images. Radiographs reveal periarticular osteoporosis with loss of cartilage in the subacute phase and flexion contracture at the later stage. MRI (STIR) allows more precise delineation of the inflammatory process compared to radiography.

Increasing benefit of magnetic resonance imaging in multiple sclerosis.

Magnetic resonance imaging (MRI) has emerged as an essential tool of multiple sclerosis (MS) diagnosis and has opened up completely new prospects in MS research and treatment trials. It is a sensitive method that gives direct evidence of tissue pathology and has greatly increased our knowledge of MS. In clinical work, MRI is used to confirm and exclude the diagnosis of MS. The international recommendation is that every suspected MS patient should undergo at least one brain MRI. T2-weighted images are the standard tool in clinical work, and functional imaging methods are mainly used in MS research. The subtypes and the course of the disease cause variation in MRI findings. Here, we present a general overview of MR findings in MS.

Gadolinium enhancement of cauda equina: a new MR imaging finding in the radiculitic form of tick-borne encephalitis.

Tick-borne encephalitis virus is an important human pathogen in Europe. The infection usually presents as meningitis, meningoencephalitis, or meningoencephalomyelitis and only rarely as symptoms of isolated myeloradiculitis. We describe the lumbar MR imaging finding in a 48-year-old man with serologically confirmed tick-borne encephalitis in which there was enhancement of the ventral surface of the conus and the anterior nerve roots from the T12 level extending along the length of the ventral cauda.

Cerebral CT and MRI findings in cervicocephalic artery dissection.

PURPOSE: To explore the frequency and patterns of brain infarction and other brain manifestations in cervicocephalic artery dissection (CCAD) and to evaluate the correlation between vessel wall findings and infarctions. MATERIAL AND METHODS: The medical records and films of 136 consecutive CCAD patients diagnosed in Oulu University Hospital during the 20-year period since 1982 were reviewed. Five patients with no brain imaging were excluded. RESULTS: One-hundred-and-twenty-seven patients underwent cerebral CT and four patients MRI. Brain infarction was detected in 73 patients (56%), 43 of whom had cerebral infarction associated with anterior circulation dissection and 30 cerebellar infarction associated with posterior circulation dissection. Occlusion of the dissected vessel was accompanied by infarction in 76%, irregular stenosis in 40%, and other findings in 12%. Of the anterior circulation infarctions, territorial and subcortical infarctions and territorial infarctions with fragmentation, which are considered embolic, accounted for 95%, while only 5% were in the watershed area and considered hemodynamic. Intracranial posterior circulation dissection rarely caused infarction (in 1/11 of the dissected vessels), whereas intracranial anterior circulation dissection resulted in infarction more commonly (9/12). Altogether 23% of patients with intracranial CCAD had subarachnoid hemorrhage. Hemorrhagic transformation was present in five patients. CONCLUSIONS: More than half of CCAD patients have cerebral or cerebellar infarction at CT or conventional MR imaging. Occlusion of the dissected vessel is accompanied by infarction more often than other vessel wall abnormalities. Most cerebral infarctions caused by arterial dissections are of embolic origin. Intracranial dissections cause subarachnoid hemorrhage in more than 20% of patients.

Magnetic resonance imaging findings and outcome in severe tick-borne encephalitis. Report of four cases and review of the literature.

PURPOSE: To describe the magnetic resonance imaging (MRI) findings of four patients with proven tick-borne encephalitis (TBE). These are the most northern cases reported from Scandinavia. Experience of turbo fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) has not previously been published in this context. MATERIAL AND METHODS: The MRI findings of four consecutive patients with TBE treated in our hospital during the year 2002 were evaluated. MRI was done during the first week of illness, and follow-up scans were available in three cases. RESULTS: In T2-weighted and turbo FLAIR images, thalamic hyperintensity was equally evident in three of the four patients. One of them also showed hyperintensity in the left putamen and the internal capsule and another patient in the peduncles and the hypothalamus. T1-weighted images without contrast were normal in all patients, and leptomeningeal enhancement was detected in only one patient. The two patients who underwent DW images did not show any restricted diffusion. Follow-up MR images showed no atrophy or necrotic foci, and the signal abnormalities disappeared during 16-34 weeks of follow-up. CONCLUSION: T2-weighted and turbo FLAIR sequences proved equally effective in detecting and delineating the thalamic, brainstem, and basal ganglia pathologies. According to our results, mechanisms other than cytotoxic edema contribute to the signal pathology. Radiologists should be familiar with the MR findings of TBE even in non-endemic areas.

Pneumothorax and the value of chest radiography after ultrasound-guided thoracocentesis.

PURPOSE: To determine the incidence, the operator's experience, and other variables that may influence the development of pneumothorax or re-expansion edema after ultrasound (US)-guided thoracocentesis. MATERIAL AND METHODS: The medical records of 264 procedures in 212 patients who had undergone US-guided thoracocentesis in our radiology department or intensive care unit during the period 1996-2001 were retrospectively reviewed. RESULTS: Post-thoracocentesis pneumothorax occurred in 11 cases, the incidence being 4.2% (11/264). None of the pneumothoraces occurred in the 10 mechanically ventilated patients. All but one patient with pneumothorax were asymptomatic or had only minor symptoms. Chest tube drainage was needed in one patient with a large pneumothorax. No re-expansion edema was recorded, although 1500 ml or more pleural fluid was aspirated in 29 patients. The operator's experience had no effect on the complication rate. Needle size was the only significant variable that contributed to the pneumothorax rate. CONCLUSION: US-guided thoracocentesis can be done equally as safely by residents as by senior radiologists. The safety and feasibility of the method are evident among mechanically ventilated intensive care patients. Our results do not support the routine use of post-thoracocentesis chest radiography.

Extracranial internal carotid and vertebral artery dissections: angiographic spectrum, course and prognosis.

We reviewed the clinical and radiological findings of 93 consecutive patients with 111 extracranial internal carotid (ICAD) and vertebral artery (VAD) dissections and one concomitant intracranial VAD; 83% of the patients had unilateral and 17% multiple vessel dissections. The diagnosis was made by intra-arterial digital subtraction angiography in 92 patients and MR angiography in one. Follow-up angiography was performed in 77 cases (83%): of 49 initially stenotic arteries, 40 became completely or almost completely normal, while three showed slight improvement. Of 30 initially occluded arteries, nine had completely or partly recanalised. Of 12 pseudoaneurysms eight were unchanged at follow-up. The proximal vertebral artery was involved as often as the C1-C2 level. Recurrences were rare: a new dissection in another vessel was found in three patients. Kinking or coiling was found in 23% of the dissected internal carotid arteries.

Lymphoma of the cervix. Imaging and transcatheter arterial embolization.

A case of uterine cervix lymphoma with selective embolization after angiography is described. Chemotherapy and radiotherapy were carried out and surgery was avoided.

MR imaging of pituitary adenomas treated with the prolactin inhibitor quinagolide.

PURPOSE: To evaluate the volume of micro- and macroadenomas in quinagolide-treated patients with resistance to or intolerance of bromocriptine. MATERIAL AND METHODS: The effect of the prolactin inhibitor quinagolide on the volume of pituitary adenoma was evaluated retrospectively in 11 female patients. Prolactin levels before and after the treatment were also recorded. The indications for quinagolide therapy were side-effects of bromocriptine in 5 cases, a poor response to bromocriptine in 5 cases and both in 1 case. MR imaging with a 1.0-T magnet was performed to determine the volume reduction of the adenomas. RESULTS: The average volume reduction of macroadenomas was 324 mm3 (46%) and that of microadenomas 73 mm3 (57%). The level of prolactin secreted by macroadenomas was reduced by an average of 163 microg/l (65%) and that by microadenomas of 113 microg (73%). In 2 microadenomas and in 1 macroadenoma, signal intensity changed during the treatment in T1-weighted images. In follow-up no changes in signal intensity were seen in 8 adenomas in non-contrast T1-weighted images. A haemorrhagic lesion was seen in 1 macroadenoma before treatment, but it disappeared during treatment. CONCLUSION: Quinagolide was found to be an effective alternative to bromocriptine in cases with drug intolerance or resistance, and MR imaging a suitable method for the follow-up of macro- and microadenomas.

Ultrasound-guided percutaneous thoracoabdominal biopsy.

This review will discuss the benefits and disadvantages of ultrasound-guided percutaneous fine-needle aspiration and cutting needle biopsies. Clinical efficacy, cost-effectiveness, some controversies and safety will be reviewed.

Isolated neurosarcoidosis - MR findings and pathologic correlation.

Neurosarcoidosis is a diagnostic challenge, especially if systemic symptoms are absent. We present a 49-year-old woman with isolated neurosarcoidosis. The main symptom was loss of vision in the left eye. Brain MR imaging showed 6 high-signal white matter lesions frontotemporally on proton density and T2-weighted turbo spin-echo images. Coronal fat-saturated turbo FLAIR images of the orbits showed a swollen left optic nerve with increased signal intensity, which finding has not been previously published in sarcoid optic neuropathy. A control MR examination showed meningeal enhancement of the left optic nerve and leptomeningeal enhancing lesions around the brain stem. Spinal MR revealed leptomeningeal enhancement throughout the spinal cord and asymptomatic enhancing cauda equina lesions, mimicking subarachnoid tumour seeding, and an enhancing nerve root mass at Th12/L1. Biopsy of the latter lesion revealed non-caseating granulomas consistent with sarcoidosis.

Percutaneous transcatheter renal embolization with absolute ethanol for uncontrolled nephrotic syndrome. Case reports.

PURPOSE: To retrospectively evaluate renal ethanol embolization in 2 patients with uncontrolled nephrotic syndrome. MATERIAL AND METHODS: Three kidneys in 2 patients with uncontrolled nephrotic syndrome were embolized with absolute ethanol. The embolization technique, patient outcome and complications were analyzed retrospectively. RESULTS: The treatment was successful in both patients, with angiography-verified exclusion of blood flow to the renal arteries. Elimination of proteinuria was achieved in both patients and their body weight decreased by 25 and 10 kg, respectively. Hospitalization and protein substitution were no longer needed. No complications occurred. CONCLUSION: Permanent bilateral ethanol embolization of the renal arteries is a feasible method of managing a treatment-resistant nephrotic syndrome in selected patients. Non-target embolization can be avoided by using a balloon occlusion catheter.