Assessing brain integrity in patients with long-term and well-functioning metal-based hip implants.

Production of metal debris from implant wear and corrosion processes is now a well understood occurrence following hip arthroplasty. Evidence has shown that metal ions can enter the bloodstream and travel to distant organs including the brain, and in extreme cases, can induce sensorial and neurological diseases. Our objective was tosimultaneously analyze brain anatomy and physiology in patients with long-term and well-functioning implants. Included were subjects who had received total hip or hip resurfacing arthroplastywith an implantation time of a minimum of 7 years (n = 28) and age- and sex-matched controls (n = 32). Blood samples were obtained to measure ion concentrations of cobalt and chromium, and the Montreal Cognitive Assessment was performed. 3T MRI brain scans were completed with an MPRAGE sequence for ROI segmentation and multiecho gradient echo sequences to generate QSM and R2* maps. Mean QSM and R2* values were recorded for five deep brain and four middle and cortical brain structures on both hemispheres: pallidum, putamen, caudate, amygdala, hippocampus, anterior cingulate, inferior temporal, and cerebellum. No differences in QSM or R2* or cognition scores were found between both groups (p > 0.6654). No correlation was found between susceptibility and blood ion levels for cobalt or chromium in any region of the brain. No correlation was found between blood ion levels and cognition scores. Clinical significance: Results suggest that metal ions released by long-term and well-functioning implants do not affect brain integrity.

Synchronous bilateral lipoma arborescens of bicipitoradial bursa-a rare entity.

Lipoma arborescens is a rare non-neoplastic condition that affects the synovial lining of joints and bursae accounting for less than 1% of all lipomatous lesions. Characterized by villous proliferation of the synovium, it is an uncommon cause of intra/periarticular mass presenting as a painless, slowly progressive longstanding swelling, and is sometimes accompanied by intermittent monoarticular effusions. We describe a rare case of bilateral lipoma arborescens in the bicipitoradial bursae in a young male referred for MRI evaluation of spontaneous bilateral elbow swelling. We chose to bring this case to light because of the rare simultaneous involvement of the bicipitoradial bursae bilaterally and the role of MR in providing a definite diagnosis, hence obviating the need for biopsy and avoiding consideration of other complex intra/periarticular masses.

Association between portal vein color Doppler findings and the severity of disease in cirrhotic patients with portal hypertension.

BACKGROUND: Doppler ultrasound is the accepted gold standard for assessing direction of flow in the portal vein (PV). Moreover, it is non-invasive; therefore, it is well accepted by the patients and does not interfere with flow hemodynamics. OBJECTIVES: The present study was aimed to evaluate the association between color Doppler findings and the severity of portal hypertension in patients with cirrhosis. PATIENTS AND METHODS: The study group included 50 patients referred for ultrasound (US) evaluation over a period of six months from March to August, 2007. The patients were divided into three groups (Child' A, B and C) based on Child Pugh classification. The direction of flow in the main portal vein (hepatopetal or nonhepatopetal) and peak venous velocity (PVV) in the main portal vein were measured and correlated with the presence or absence of ascites, splenomegaly, splenic and esophageal varices (assessed by Doppler US). These findings were correlated with clinical features and laboratory findings (using Child Pugh's criteria). RESULTS: There was significant association between the decrease of peak portal venous velocity (PVV) and the increase in Child Pugh score. Hepatofugal flow was seen only in patients with more advanced disease. There was also significant association between PVV and splenic varices and ascites, while PVV was not affected by the presence or absence of esophageal varices or splenomegaly. Presence of a recanalized umbilical vein (UV) was associated with increased PVV even in advanced disease. CONCLUSIONS: Color Doppler is an excellent modality for detecting and characterizing the complex hemodynamics of portal hypertension in cirrhosis and they correlate with the clinical stage of disease.

Case report: MRI of the brain in metronidazole toxicity.

Metronidazole is a commonly used antimicrobial drug. When used excessively, it can cause encephalopathy. We report the MRI findings in one such case. A 43-year-old male patient was treated with metronidazole for 2 months, for an amebic liver abscess and presented with neurological signs and symptoms. MRI of the brain showed findings consistent with metronidazole toxicity.

Pictorial essay: Susceptibility-weighted imaging in cerebral ischemia.

The susceptiblity effect in magnetic resonance imaging (MRI) has been recognized for long and often has been considered undesirable, producing unnecessary noise. Susceptibility-weighted imaging (SWI) aims at exploiting this effect to provide a different type of contrast that is suited for vascular imaging. We describe five different cases in which SWI was found useful to delineate the underlying ischemia or to arrive at the corect diagnosis.

Holocord intramedullary abscess.

Intramedullary spinal cord abscess secondary to dorsal dermal sinus is a rare entity and involvement of the entire length of spinal cord is even rarer. A thorough history with precise clinical localization, a high index of suspicion, Magnetic Resonance Imaging (MRI) of spine and prompt surgical drainage with appropriate antibiotic therapy are key to the eventual outcome and prognosis.