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Uday Patel

Publications and source records attributed to Uday Patel.

10 recordsLinked to original sources
PubMed2005

Three-dimensional planning of percutaneous renal stone surgery in a horseshoe kidney using 16-slice CT and volume-rendered movies.

Percutaneous management of calculi within horseshoe kidneys can be difficult because of the abnormal renal anatomy. We report our use of 16-slice CT scans to obtain three-dimensional (3D) volume-rendered (VR) movies of the pelvicaliceal system and stone for planning percutaneous renal stone surgery. The movie is formatted onto a disc, which can be played on a personal computer without additional software. This technique allows user-friendly 3D planning in the operating theatre. Unlike conventional two-dimensional images, the 3D VR movie provides a global appreciation for planning.

Endoscopy↗
PubMed2005

Size matters: a survey of how urinary-tract stones are measured in the UK.

BACKGROUND AND PURPOSE: Stone size forms the basis of management pathways in patients with urolithiasis. We carried out a questionnaire-based audit to find out how stone size is routinely measured by radiologists in the UK. MATERIALS AND METHODS: A series of 831 anonymous questionnaires concerning how stone size is assessed using four imaging modalities--plain abdominal radiograph (KUB film), intravenous urogram (IVU), ultrasound, and CT--were sent to 277 radiology departments. Following the survey, a substudy at our institution compared urologists (N = 10) and radiologists (N = 5) in estimating the size of a large (26-mm) and small (11- mm) calculus on KUB films. RESULTS: Of the questionnaires, 425 were returned, and 421 were analyzed. Of these, 85% were from consultants, 14% from trainees/middle grades, and 1% "unspecified." In total, 92% of the respondents were radiologists (10% uroradiologists) and 8% urologists. Estimation of stone size ("guestimation") from KUB films and IVUs was used by 40% and 36% of radiologists, respectively, whereas graded rulers were used by 57% and 59%, respectively. For ultrasound scans and CT, electronic measurement was the favored method (81% and 73%), but guestimation was still used by 10% and 15%, respectively. When assessing the KUB films and IVU, 59% and 61% of urologists, respectively, also used guestimation. The substudy revealed a significant difference among radiologists in the accuracy of size estimation for the 11-mm stone (mean estimated size 9.6 mm; P = 0.02, one-sample t-test). CONCLUSION: A large proportion of radiologists use guestimation for assessing stone size on KUB films and IVU. Even when electronic measuring aids were available for CT and ultrasonography, guestimates remained prevalent. Our substudy showed that radiologists significantly underestimated the smaller stone.

Diagnostic Imaging↗
PubMed2004

Percutaneous nephrostomy of nondilated renal collecting systems with fluoroscopic guidance: technique and results.

PURPOSE: To retrospectively review experience with a double-puncture technique for percutaneous nephrostomy of nondilated renal collecting systems. MATERIALS AND METHODS: Over a 5-year period, 15 patients (26 kidneys) without calyceal dilatation at ultrasonography (US) who required nephrostomy drainage were studied. Eleven patients (21 kidneys) had ureteral leaks or fistulas, one patient (one kidney) had a renal pelvic stone, one patient (one kidney) was suspected of having a ureteral tumor, and the final two patients (three kidneys) had acute nondilated renal failure. Mean age was 62 years (range, 20-78 years); 13 patients were men and two were women. A double-puncture technique was used with fluoroscopic guidance (supplemented with US in some patients who had renal failure). After intravenous administration of iodinated contrast material, a 22-gauge needle was inserted into the opacified renal pelvis, and double-contrast pyelography was performed by using air or carbon dioxide to allow visualization and distention of the nondependent calyces for definitive renal access with an 18-gauge 5-F sheath-needle set and a hydrophilic wire. After serial dilation, a nephrostomy or nephroureteral catheter was inserted. Success and major complication rates were studied by reviewing radiologic and clinical case notes. RESULTS: Catheter placement was successful in 25 (96%) of 26 kidneys after one, two, or three passes with the sheath-needle set. In all successful cases, the calyx was accurately punctured. There were two major complications. One patient developed hematuria that required transfusion but no further intervention; another sustained a renal pelvic injury, but this was believed to be due to excessive dilation of the pelviureteral junction, not faulty renal puncture. There were no cases of septicemia. CONCLUSION: With a double-puncture technique and air or carbon dioxide distention, nephrostomy was achieved in 25 (96%) of all nondilated renal collecting systems. There were two major complications (two [8%] of 25 kidneys, two [13%] of 15 patients), but only one was secondary to the renal puncture.

Adult↗
PubMed2004

Kinks of the transplant renal artery without accompanying intraarterial pressure gradient do not require correction: five-year outcome study.

Significant transplant renal artery stenosis (TRAS) results in an intraarterial pressure gradient and increasing graft dysfunction correctable by endovascular therapy. Kinks of the transplant artery cause velocity gradients on Doppler ultrasound, but some will have no intraarterial pressure gradient across the kink. It is not known whether these nonflow limiting kinks progress further to threaten graft function and should undergo endovascular correction. This is a longitudinal study of conservatively managed arterial kinks to define their natural history. Fourteen patients who had undergone angiography over a 5-year period for suspected TRAS had kinks of the renal artery. True intraarterial pressures were measured in all cases by slow withdrawal of an end-hole catheter after intraarterial injection of a vasodilator. Those with a significant pressure change (> or =10% change in peak systolic pressure across the area of suspicion) underwent endovascular treatment. The rest were managed conservatively, with maximal antihypertensive therapy. Outcome of all 14 cases was determined by follow-up of creatinine levels, blood pressure (BP) control and graft outcome over a 3-5-year period (median 4 years). Of the 14 patients with kinks, 10 were male and 4 female; age range 23-67 years (mean 47 years). Eleven had received cadaveric transplants and 3 were allografts; 12 had end-to-side and 2 end-to-end anastomosis, 11/14 cases had an intraarterial pressure ratio of <10% and at median 4 years follow-up on conservative treatment, the serum creatinine of these 11 patients did not differ significantly from those who underwent successful endovascular treatment (mean 118 micromol/l versus 149 micromol/l; p = 0.30, Mann Whitney test). Mean blood pressure was 137/82 mmHg, with a range of 124-155/56-95 mmHg. Only one patient has required an unexplainable increase in antihypertensive medication. Grafts (2/11) were lost and both had chronic rejection on histology. There were no unexplained graft failures. Kinks of the renal transplant artery with normal intraarterial pressures do not appear to progress and threaten renal graft function. Satisfactory graft outcome was seen on 5-year follow-up with conservative therapy alone.

Adult↗
PubMed2004

Success and short-term complication rates of percutaneous nephrostomy during pregnancy.

Outcome of percutaneous nephrostomy creation during pregnancy was retrospectively studied. Catheter insertion was successful in all cases (N = 8; 3% of all nephrostomies over a 5-year period), with one major complication (sepsis) and three minor complications. Catheters remained in situ for a mean of 9.4 days until the stone passed (n = 1) or was removed on ureteroscopy (n = 2) or a ureteral stent was inserted (n = 5). Maternal outcome was normal in all cases, but there were two premature deliveries. Nephrostomy during pregnancy has acceptable technical and clinical results, but the possibility of an increased risk of septic complications (12.5% in this series) necessitates further study.

Adult↗
PubMed2004

Bleeding after transrectal ultrasonography-guided prostate biopsy: a study of 7-day morbidity after a six-, eight- and 12-core biopsy protocol.

OBJECTIVE: To compare, in a prospective study, bleeding (in three categories, i.e. haematuria, haematospermia and rectal) and consultations with the general practitioner (GP), after a six-, eight- or 12-core prostate biopsy, as data on whether taking more prostate core biopsies increases bleeding complications are not conclusive. PATIENTS AND METHODS: Over a 5-year period, patients undergoing outpatient transrectal ultrasonography (TRUS)-guided prostate biopsy (six, eight or 12-core biopsy) completed a self-administered questionnaire. The prevalence and duration of the three bleeding complications and GP or hospital visits for a biopsy-related complication were assessed and compared for the 7 days after biopsy. The contribution of local anaesthetic (LA) injection to bleeding rates was also assessed. RESULTS: Of 1384 patients biopsied, 1000 were given questionnaires and 884 (88%) forms were returned. Of these, 760 were suitable for analysis (307 after six-core, 325 eight-core and 128 12-core biopsies); 351 patients were given LA before biopsy. The prevalence of bleeding complications (six-, eight- and 12-core, respectively) was: haematuria 44%, 41% and 39%; haematospermia 13%, 16% and 12%; and rectal bleeding 17%, 26% and 27%. Rectal bleeding was significantly more prevalent in the eight- and 12-core groups (P = 0.0037 and 0.019). The duration of bleeding was not significantly greater in any biopsy group. Subgroup analysis showed no significant difference in the prevalence and duration of rectal bleeding after LA. About 5% of patients in each group consulted their GP because of a complication and 2.4% consulted because of bleeding. Three men with major complications required hospitalization, of which only one was caused by bleeding. CONCLUSIONS: Only rectal bleeding was more prevalent after taking more than six cores, but the duration was no greater. Giving LA did not affect the rectal bleeding rate. With all strategies the major complication and hospitalization rate was very low.

Adult↗
PubMed2003

Ureteral stent placement without postprocedural nephrostomy tube: experience in 41 patients.

PURPOSE: To evaluate one-stage antegrade ureteral stent placement without postprocedural nephrostomy tube. MATERIALS AND METHODS: Tubeless ureteral stent insertion was attempted in 41 (30 men, 11 women; eight, benign obstruction; nine outpatients) of 97 adults (56 excluded). Patients were clinically stable with known ureteral obstruction and had been referred for antegrade ureteral stent insertion. Exclusion criteria were infection, coagulopathy, or emergency cases. After renal access was achieved, ureteral stents were inserted. If drainage was satisfactory and there was no marked procedural bleeding, all access was removed without leaving a nephrostomy tube behind. Technical and clinical success rates and complications were assessed with review of radiologic and clinical notes. If one-stage stent insertion was unsuccessful, a nephrostomy tube was inserted and two-stage stent placement was performed. All 56 patients excluded from this study underwent two-stage stent placement. Major complication rate was assessed (Fisher test). RESULTS: One-stage stent insertion was technically successful in 36 (88%) patients; two with an identifiable risk factor (recent bladder operation, retrograde ureteral instrumentation) developed septicemia that required repeat nephrostomy tube insertion and 2-8 extra days of hospitalization. Clinical success rate was 83% (34 of 41). No major bleeding occurred. In 13 (36%) of 36 patients, hematuria lasted longer than 24 hours but resolved without further intervention or blood transfusion. In those who underwent two-stage stent placement (n = 61), technical success rate was 100%, but clinical success rate was 98%; one patient developed septicemia, and no major hemorrhage occurred. Difference in major complication rate between groups was not significant (6% [two of 36] vs 2% [one of 61]; P =.55). CONCLUSION: One-stage tubeless antegrade ureteral stent insertion in selected cases showed 88% technical success rate and 83% clinical success rate, with no major hemorrhage.

Adult↗