Persistent enhancement after treatment for cerebral toxoplasmosis in patients with AIDS: predictive value for subsequent recurrence.

PURPOSE: To determine the predictive imaging (CT and/or MR) features of brain toxoplasmosis recurrences in acquired immunodeficiency syndrome. METHODS: The imaging studies of patients with brain toxoplasmosis were retrospectively reviewed. Forty-three patients with significant decrease or disappearance of brain lesions under specific treatment on follow-up imaging examinations were included. MR examinations were performed using T2- and T1-weighted sequences, before and after intravenous administration of gadolinium-DOTA. RESULTS: A recurrence occurred in 11 (26%) of 43 cases. Ten (91%) of these 11 patients with recurrence showed focal persistent enhancement after the initial treatment of toxoplasmosis abscess. One of the 11 patients with recurrence showed no persistent enhancement; 3 patients showed persistent enhancement but had no recurrence. CONCLUSIONS: Recurrences of brain toxoplasmosis in our series correlated with persistent contrast enhancement. We hypothesize that demonstration of persistent areas of contrast enhancement after treatment for initial toxoplasmosis may be a valuable sign for identifying patients at risk for recurrence.

Complications of flexor tendon repair in the hand: MR imaging assessment.

PURPOSE: To determine if magnetic resonance (MR) imaging enables differentiation of adhesions from tendon rupture after repair of digital flexor tendon injuries. MATERIALS AND METHODS: The reference group comprised eight tendon sutures with a good clinical outcome. Axial and sagittal spin-echo sequences and three-dimensional gradient-echo sequences with curved reconstructions were analyzed in 63 injured fingers. Reoperation was performed in 41 fingers. RESULTS: MR imaging depicted isolated peritendinous adhesions (n = 31), most often with a continuous, uniform tendon (sensitivity 91%, specificity 100%). There were two types of rupture: frank rupture (n = 140; sensitivity 100%, specificity 100%) or elongated callus (n = 18; sensitivity 100%, specificity 94%). Tendon gap was significantly longer in frank rupture (P = .0011). Thin fibrous continuity existed with elongated callus. Tenolysis was sufficient when the callus was short and mature with predominant new collagen fibers. Axial spin-echo sections were essential, as they showed the maturation of the callus. CONCLUSION: MR imaging may enable distinction among several complications that occur after repair of an injured digital flexor tendon.