The development of valvular strands during thrombolytic therapy detected by transesophageal echocardiography

A case report of a patient who had valvular strands while undergoing treatment with thrombolytic therapy for prosthetic mitral valve thrombosis is presented. The development of valvular strands during thrombolytic therapy provides unique evidence supporting a thrombotic/fibrotic origin to this relatively common finding on transesophageal echocardiography.     

Renal cyst rupture following blunt abdominal trauma: case report

HLA typing was performed on 18 patients suffering from sarcoidosis and 30 patients suffering from diffuse interstitial pulmonary fibrosis. One hundred normal healthy people ethnically matched served as the controls. On statistical analysis, the corrected 'p' value of all the HLA antigens for both the patient groups was non significant. The results therefore suggest that there is no particular HLA antigen associated with sarcoidosis and diffuse interstitial pulmonary fibrosis.     

Effect of geometrical distortion correction in MR on image registration accuracy

In this article we investigate the effect of geometrical distortion correction in MR images on the accuracy of the registration of X-ray CT and MR head images for both a fiducial marker (extrinsic point) method and a surface-matching technique. We use CT and T2-weighted MR image volumes acquired from seven patients who underwent craniotomies in a stereotactic neurosurgical clinical trial. Each patient had four external markers attached to transcutaneous posts screwed into the outer table of the skull. The MR images are corrected for static field inhomogeneity by using an image rectification technique and corrected for scale distortion (gradient magnitude uncertainty) by using an attached stereotactic frame as an object of known shape and size. We define target registration error (TRE) as the distance between corresponding marker positions after registration and transformation. The accuracy of the fiducial marker method is determined by using each combination of three markers to estimate the transformation and the remaining marker to calculate registration error. Surface-based registration is accomplished by fitting MR contours corresponding to the CSF-dura interface to CT contours derived from the inner surface of the skull. The mean point-based TRE using three noncollinear fiducials improved 34%-from 1.15 to 0.76 mm-after correcting for both static field inhomogeneity and scale distortion. The mean surface-based TRE improved 46%-from 2.20 to 1.19 mm. Correction of geometrical distortion in MR images can significantly improve the accuracy of point-based and surface-based registration of CT and MR head images. Distortion correction can be important in clinical situations such as stereotactic and functional neurosurgery where 1 to 2 mm accuracy is required.     

Ultrasonic ventriculostomy stylet

I describe my design for a ventriculostomy stylet fitted with a phase array ultrasonic imaging device in its tip. Theoretically, this would allow identification of the ventricles and their exact location at the bedside, without the need for expensive stereotactic equipment. A device such as this could potentially facilitate the placement of ventriculostomy catheters in patients with small ventricles, and it could even contribute to the education of neurosurgery residents. At present, a prototype of the device is being manufactured.     

Composition of nasal secretion in patients with cystic fibrosis

Quantitative examination of nasal secretion in patients with cystic fibrosis revealed a significantly greater than normal concentration of calcium, a finding in keeping with the hypothesized importance of this ion in the pathophysiology of the disease.     

Primary mediastinal lymphoma in adults

The incidence of primary mediastinal lymphoma in adults was investigated in 184 patients with non-Hodgkin's lymphoma. This entity was defined as disease within the mediastinum in patients who presented with symptoms due to an enlarging mediastinal mass. Of 184 patients, 17 presented with primary mediastinal lymphoma. All had a diffuse histologic pattern. The most common pathologic type was poorly differentiated lymphocytic lymphoma, diffuse (PDL-D), (11 cases). In nine of these 11 cases the patients had tumors of convoluted lymphocytes. The presentation was rapid in onset, with heart failure, pericarditis, dyspnea and superior vena caval syndrome predominating. Eleven of the 17 were clinical stage I or II, but eight of these had widespread disease on pathologic staging or rapid dissemination soon after diagnosis. In conclusion (1) primary mediastinal lymphoma is always diffuse in histology. (2) The most frequent pathologic type is PDL-D, with convoluted morphology. (3) Compression of vital intra-thoracic structures is common. (4) Although seemingly localized at presentation, this entity usually implies disseminated disease.