Virtual cystoscopy: reality in imaging of bladder tuberculosis.

We present a case of urinary tuberculosis investigated initially by ultrasound and multidetector computed tomography (MDCT). The MDCT-derived volumetric data were used to generate virtual cystoscopy (VC) images, which revealed a bladder ulcer. The presence of this ulcer was confirmed by conventional cystoscopy-guided biopsy and there was good agreement regarding various features of the ulcer, such as the site, size and shape, as detected by virtual and conventional cystoscopies. VC, a result of simple postprocessing of preacquired MDCT data, proved valuable in the characterization of the bladder lesion in conjunction with CT and ultrasound images. Although a larger study is warranted, in our case these en face VC representations of the ulcer served as useful precursors to conventional cystoscopic biopsy.

Ultrafast MRI in the prenatal diagnosis of Bourneville's tuberous sclerosis.

The purpose of this report is to highlight the utility of prenatal MRI as an adjunctive imaging modality in the diagnosis and prognosis of Tuberous Sclerosis (TS) (Bourneville's disease). We report a case of TS detected in utero at 30 weeks gestation. A routine ultrasonography at 26 weeks in a 28-year-old primigravida was followed by an ultrafast MRI examination at 30 weeks gestation. Ultrasound raised the possibility of TS based on the detection of multiple cardiac rhabdomyomas. Fetal MRI, subsequently performed, showed the presence of cortical tubers and subependymal nodules establishing the diagnosis. Fetal MRI in the appropriate clinical setting can be potentially invaluable and can have important prognostic implications.

Magnetic resonance urography (MRU) versus intravenous urography (IVU) in obstructive uropathy: a prospective study of 30 cases.

AIM: Intravenous Urography (IVU) as a diagnostic modality has limitations in patients of obstructive uropathy with impaired renal function. Our aim was to study the technique and diagnostic accuracy of Magnetic Resonance Urography (MRU) in obstructive uropathy and to correlate the findings with IVU. METHODOLOGY: Forty-eight patients, selected over a six-month period, based on mild to severe pelvicalyceal dilatation on screening ultrasonography, underwent an IVU; those having non-obstructive dilatation were excluded (18 patients). Thirty patients (age range 10 to 75 years) with definite obstructive dilatation underwent MRU. These were obtained using an open MRI unit (Siemens Magnetom Open Viva) with low-dose gadolinium-DTPA (0.01 mmol/kg body weight) using various MRI sequences. MRU studies were classified as 'excellent' or 'diagnostic' and data generated was compared with that of IVU. RESULTS: MRU studies were 'excellent' in twelve and 'diagnostic' in eighteen patients. Of the sixty pelvicalyceal systems (PCS) evaluated in thirty patients, there were thirty-seven calculi, nine pelvi-ureteric junction (PUJ) obstructions, six with impaired renal function, four malrotated kidneys and one each of horseshoe kidney, pancake kidney, pelvic mass (endometriomas), duplex moieties, ureterocele and vesico-ureteric reflux. MRU better depicted moderate-severe PCS dilatation, staghorn and urethral calculi, impaired renal function, extrinsic ureteric and PUJ obstruction. IVU better depicted small calculi and mild PCS dilatation. CONCLUSIONS: In these thirty patients of obstructive uropathy, low magnetic field, open MRI units and low-dose Gd-DTPA provided cost-effective MRU studies with excellent diagnostic utility. MRU scored over IVU in patients with moderate-severe dilatation, staghorn and urethral calculi, impaired renal function, extrinsic ureteric and PUJ obstruction.

Role of multidetector CT virtual bronchoscopy in the evaluation of post-tracheostomy tracheal stenosis--a preliminary study.

AIM: To study the technique and utility of virtual bronchoscopy (virtual reality endobronchial simulation, VRES) as a tool to evaluate post-tracheostomy tracheal stenoses and to correlate the findings of virtual and invasive bronchoscopy and to follow-up treated lesions or those currently under treatment that were initially diagnosed with VRES. METHODOLOGY: This prospective study comprised nine patients in the age group 13 to 65 years presenting with breathlessness and stridor following one or multiple tracheostomies. They underwent plain CT using a multidetector CT (MDCT) scanner (Siemens Volume Zoom) using narrow (1 mm) collimation. These thin slice images were post-processed using an Irix-based workstation with a 'Fly-Through' endoscopy application. These patients also underwent a rigid (three patients) or fiberoptic (six patients) bronchoscopy. RESULTS: Of the nine patients that underwent VRES, five were found to have stenoses, three had obstructing granulation tissue, one had an obstructing membrane and one had synechiae. The invasive bronchoscopic findings supported the VRES diagnosis in all but one case of stenosis, one of granulation tissue and the case with synechiae. Membranes and synechiae were relatively difficult to diagnose without the corresponding axial and multiplanar images. VRES achieved a higher sensitivity, while invasive bronchoscopy a higher specificity. CONCLUSIONS: VRES proved to be comparable to invasive bronchoscopy in the depiction of post-tracheostomy tracheal stenoses, with a notable advantage in critical stenoses in that the airway distal to the stenosis could be assessed with VRES but not with invasive bronchoscopy. A preliminary VRES was found to be of assistance in the selection of patients for the more invasive therapeutic procedures such as laser ablation of granulation tissue and its follow-up.