CT perfusion scanning with deconvolution analysis: pilot study in patients with acute middle cerebral artery stroke

PURPOSE: To measure mean cerebral blood flow (CBF) in ischemic and nonischemic territories and in low-attenuation regions in patients with acute stroke by using deconvolution-derived hemodynamic imaging. MATERIALS AND METHODS: Twelve patients with acute middle cerebral artery stroke and 12 control patients were examined by using single-section computed tomography (CT) perfusion scanning. Analysis was performed with a deconvolution-based algorithm. Comparisons of mean CBF, cerebral blood volume (CBV), and mean transit time (MTT) were determined between hemispheres in all patients and between low- and normal-attenuation regions in patients with acute stroke. Two independent readers examined the images for extent of visually apparent regional perfusion abnormalities. The data were compared with extent of final infarct in seven patients with acute stroke who underwent follow-up CT or magnetic resonance imaging. RESULTS: Significant decreases in CBF (-50%, P =.001) were found in the affected hemispheres of patients with acute stroke. Significant changes in CBV (-26%, P =.03) and MTT (+111%, P =.004) were also seen. Significant alterations in perfusion were also seen in low- compared with normal-attenuation areas. Pearson correlation between readers for extent of CBF abnormality was 0.94 (P =.001). Intraobserver variation was 8.9% for CBF abnormalities. CONCLUSION: Deconvolution analysis of CT perfusion data is a promising method for evaluation of cerebral hemodynamics in patients with acute stroke

Muscle belly union associated with simultaneous medial rectus recession for treatment of myopic myopathy: results of 33 eyes

PURPOSE: To describe the results achieved using muscle belly union associated with the recession of the ipsilateral medial rectus muscle to treat myopic myopathy and restore the normal anatomical relationship of superior and lateral rectus (LR). METHODS: A retrospective, nonrandomized study performed on 33 eyes of 26 patients who underwent muscle belly union between January 2004 and October 2012. We preoperatively and postoperatively recorded: best-corrected visual acuity; refraction; intraocular pressure; complete orthoptic assessment, including the angle of deviation and maximal abduction measured using the Goldmann perimeter. Pictures of the eyes in all gaze directions were taken before and after the surgical treatment. Anatomical relationships between muscle cone and eye globe were preoperatively analyzed using magnetic resonance imaging (MRI). Surgical complications were noted. RESULTS: The follow-up period was 6 months. Preoperative mean BVCA was 0.97 \ub1 0.96 logMAR (ranging from 0.1 to 3 logMAR) and no changes were detected during postoperative controls. Preoperative mean hypotropia and esotropia were, respectively, 10.2 \ub1 3.9 prism diopters (PD) and 46.2 \ub1 15.5 PD. Postoperative mean hypotropia was 2.48 \ub1 2.00 PD (P<0.001) and mean esotropia was 7.36 \ub1 9.09 PD (P<0.001). A statistical incrementation of mean maximal abduction (P<0.001) was also noticed. CONCLUSIONS: Muscle belly union-coupled with the recession of the ipsilateral medial rectus muscle when considered convenient-is the elective surgical technique in myopic myopathy, when a downward displacement of LR muscle is shown on MRI with coronal sections