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.

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.

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.