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U Patel

Publications and source records attributed to U Patel.

At least 19 recordsLinked to original sources
PubMed2006

Current status of transrectal ultrasound-guided prostate biopsy in the diagnosis of prostate cancer.

In contemporary practice, most prostate cancers are either invisible on ultrasound or indistinguishable from concurrent benign prostatic hyperplasia. Diagnosis therefore rests on prostate biopsy. Biopsies are not simply directed at ultrasonically visible lesions, as these would miss many cancers; rather the whole gland is sampled. The sampling itself is systematic, using patterns based on prostate zonal anatomy and the geographical distribution and frequency of cancer. This review explains the evolution of the prostate biopsy technique, from the classical sextant biopsy method to the more recent extended biopsy protocols (8, 10, 12, >12 and saturation biopsy protocols). Extended protocols are increasingly being used to improve diagnostic accuracy, especially in those patients who require repeat biopsy. This trend has been facilitated by the ongoing improvement in safety and acceptability of the procedure, particularly with the use of antibiotic prophylaxis and local anaesthesia. The technical details of these extended protocols are discussed, as are the current data regarding procedure-related morbidity and how this may be minimized.

Age Factors↗
PubMed2006

Diagnosis of angiomyolipoma using computed tomography-region of interest < or =-10 HU or 4 adjacent pixels < or =-10 HU are recommended as the diagnostic thresholds.

AIM: To study and compare the diagnostic accuracy of region of interest (ROI) density measurement and pixel mapping [computed tomography (CT) density of individual pixels] for the diagnosis of renal angiomyolipoma (AML) using CT. MATERIALS AND METHODS: A study group of histologically proven AMLs was compared with a control group of histologically proven renal cell cancers, normal renal parenchyma, and simple renal cysts. The mean tissue density (ROI circle) and a pixel density map were recorded. The diagnostic accuracy of various thresholds of ROI and pixel mapping values were compared using receiver operating characteristic curves. RESULTS: Twenty-two AMLs, 16 renal cell carcinomas (RCCs), 30 simple cysts, and 30 sites of renal parenchyma were evaluated. The mean (+/-1 SD) density of the AMLs was significantly lower [-15.2(20.8) units] than the three control groups [+36.0(8.1) units, +5.4(3.4) units and +22.2(46.5) units for RCC, renal cyst and parenchyma respectively; p < 0.001 (analysis of variance)]. The sensitivities and specificities of the ROI diagnostic thresholds of < or =0 units, < or =-10 units and < or =-20 units were 77 and 97%, 73 and 100% and 50 and 100%, respectively. Using pixel mapping [diagnostic thresholds of either a line of 4 pixels < or =-10 units or a square of 4 pixels < or =-10 units] the sensitivity improves to 86% with a specificity of 97%. CONCLUSION: Although a ROI threshold value of < or =-10 units has a very high specificity (100% in the present study) the sensitivity is modest at only 73%. Pixel mapping is more sensitive for recognizing small clusters of fat. In practice, both methods can be recommended for the analysis of suspected AMLs. ROI density measurement is convenient when analysing large areas of suspected fat and < or =-10 units should be used as the diagnostic threshold. When faced with small lucent areas or indeterminate values after ROI analysis, pixel mapping is recommended using a line of 4 pixels < or =-10 units or a square of 4 pixels < or =-10 units as the discriminating thresholds.

Adult↗
PubMed2005

Tuberose sclerosis complex: analysis of growth rates aids differentiation of renal cell carcinoma from atypical or minimal-fat-containing angiomyolipoma.

AIM: To study the radiological characteristics of renal masses in individuals with tuberous sclerosis complex (TSC) using serial CT, and to examine how renal cell carcinoma (RCC) may be differentiated from indeterminate cysts or masses. METHODS: This was a retrospective study of 12 cases of TSC in which dedicated renal CT followed after US had demonstrated cystic or sonographically unusual renal masses. The CT density of all masses was measured and the masses categorized as simple cysts, complex cysts, angiomyolipomas or indeterminate solid masses. Subjects were maintained on regular follow-up with repeat CT or MRI and interval renal US. Indeterminate masses that showed rapid growth were considered suspicious for renal cell carcinoma and biopsy or nephrectomy followed. RESULTS: Comparative data were available for a median of 4 years. In each case the renal masses were multiple and bilateral; mean mass diameter was 3.6 cm. Among a total of 206 masses, 18 were simple cysts and 3 were complex cysts. Of the complex cysts, 1 proved to be an angiomyolipoma on histology and the other 2 showed no growth. Of the solid masses, 133 were typical angiomyolipomas (AMLs) and 52 were indeterminate. On follow-up, only 3 indeterminate masses showed rapid growth (>0.5 cm/year), of which only 1 proved to be an RCC on biopsy. The other 2 were minimal-fat AMLs, and the remainder of the masses showed no or slow growth. CONCLUSION: Many renal masses associated with TSC are radiologically indeterminate. A growth threshold of >0.5 cm/year identified the only RCC in this study (0.5% of all masses). Yearly radiological follow-up of indeterminate renal masses is recommended for individuals with TSC.

Adolescent↗
PubMed2004

Major complications after percutaneous nephrostomy-lessons from a department audit.

AIM: To audit the performance of our percutaneous nephrostomy service by comparing the major complication rate with the standards recommended by the Society of Cardiovascular and Interventional Radiology and the American College of Radiology: major haemorrhage in <4%, and septic shock in <4%. Secondary aims were to identify common sources of errors for quality improvement measures. METHODS: Major complications sustained between January 1997-December 2002 were identified. All cases had been carried out by the interventional radiology service of a large teaching hospital with the assistance of a nurse and radiographer, under fluoroscopic and ultrasound guidance using a Seldinger technique. Existing department protocols specified pre-procedure antibiotics for suspected infected cases and normal coagulation studies. From records and review of case notes pertinent clinical/procedural details and eventual outcome were assessed. The following were particularly noted: adherence to protocols, clinical status at time of procedure, delay in referral, complication sustained, signs of infection or coagulopathy, timing of procedure (in versus out of hours), level of operator and technical faults. RESULTS: Ten of 318 (3.1%) cases sustained a major complication: five had sepsis alone, two haemorrhage (one with sepsis as well) and three patients had a major pelvic injury (one with sepsis as well). Thus the major sepsis and haemorrhage rates were 2.2 and 0.6%, and were within the recommended threshold limits but proportionately more complications occurred out of hours: six of 105 (5.7%) versus four of 312 (1.8%; p=0.087). Sepsis was the most serious complication and may have contributed to the death of two patients. On individual case analysis, failed instrumentation with delay to definitive renal drainage was a common factor with sepsis; but the following were contributory factors in one or more cases: omitted antibiotics (in three of 10; two became septic), technical factors in four cases [medial renal puncture (n=1), damage due to fascial dilator (n=1) or peelaway sheath (n=2)] and delay in diagnosis/therapy (of 1-8 days, in six of 10 cases of whom four out of six became septic). One pelvic injury required surgical correction (contributory factor-faulty use of peelaway sheath). Patients with haemorrhage settled with prolonged tube drainage alone. CONCLUSION: An adequately staffed percutaneous nephrostomy service can perform within published clinical standards. Best practice factors identified were: attention to agreed protocols and algorithms, pre-procedure antibiotics, careful renal puncture and care with use of dilators/peelaway sheaths, but the paramount finding was that sepsis was the most serious complication, contributing to death (two of 10 in this study) or a significant increase in the level of care required. The risk is greatest after failed instrumentation (retrograde ureteral stent or percutaneous nephrostomy insertion) and particularly if there is a further delay before establishment of renal drainage. A close working relationship between interventional radiologists and urologists is crucial.

Adult↗
PubMed2004

Randomized trial of lidocaine vs lidocaine/bupivacaine periprostatic injection on longitudinal pain scores after prostate biopsy.

PURPOSE: Periprostatic lidocaine reduces immediate post-prostate biopsy pain but still many men will not consent to re-biopsy. We performed a randomized study to assess whether adding long acting local anesthesia to a short acting agent would further reduce pain. MATERIALS AND METHODS: A total of 300 men undergoing transrectal ultrasound guided prostate biopsy were sequentially randomized to receive either short acting local lidocaine (lid) or short and long acting lidocaine and bupivacaine (lid/bup). A 7-day questionnaire was used to study daily pain (10-point visual analog score), bleeding (hematuria, PR bleeding, hematospermia), visits to the family doctor and analgesic use, and whether they would agree to future re-biopsy. RESULTS: Of the 256 questionnaires returned 250 were suitable for analysis. Cross-sectional comparison showed no intergroup differences in mean pain scores immediately after biopsy (2.24, 95% CI 1.94-2.5 vs 2.61, 95% CI 2.3-2.9, p = 0.88 in lid and lid/bup groups, respectively). There was a significant rebound in visual analog scale at 1 hour in the lid group but not in the lid/bup group (+ 0.9 vs + 0.09, p = 0.0006). Longitudinal analysis showed the global pain experience after lid/bup was better compared to lidocaine alone, with significantly less pain every subsequent day (p = 0.0006 to 0.002). No difference was seen in morbidity, analgesia usage or number refusing future re-biopsy (9.6% vs 9.8%). CONCLUSIONS: Long and short acting local anesthetics together significantly attenuate the 1-hour rebound increase in pain scores seen after short acting anesthesia alone. Improved pain scores were sustained during the subsequent week and we advocate routine combination use for transrectal ultrasound guided prostate biopsy.

Aged↗
PubMed2004

Delivering cognitive therapy to people with psychosis in a community mental health setting: an effectiveness study.

OBJECTIVE: Cognitive therapy (CT) has been shown to be an efficacious treatment for persistent psychotic symptoms. However, there is some debate regarding whether this is transportable to real life clinical settings. This study aimed to evaluate the effectiveness of CT for psychosis in a community mental health team (CMHT) setting. METHOD: Patients referred for CT for psychosis were naturalistically allocated (determined by the availability of a therapist) to CT or waiting-list (WL)/treatment-as-usual (TAU). Outcome assessments were performed at WL, pre-CT, post-CT and 1-year follow-up. Data from 59 patients were analysed. RESULTS: Random effects regression analyses showed there was a significant improvement, attributable to CT, on most outcome measures, and that many of the symptomatic improvements were maintained at follow-up. Wilcoxon signed ranks tests indicated that there was a significant reduction in psychiatric hospital use following CT. CONCLUSION: These results confirm that CT is an effective treatment for psychosis that is generalizable to a community setting.

Adolescent↗
PubMed2003

Urinary tract stones--Part I: role of radiological imaging in diagnosis and treatment planning.

The modern management of urolithiasis requires a multi-disciplinary approach. Imaging plays a central role in both diagnosis and planning therapy of renal and ureteric calculi. This article reviews the current status of diagnosis and management of stone disease, and the contribution of radiological imaging in accurately triaging a given case to the most appropriate therapy.

Humans↗
PubMed2003

Urinary tract stones--Part II: current status of treatment.

The majority of renal and ureteric stones are now managed by minimally invasive techniques, for example nephrostomy, ureteral stents, extracorporeal shockwave lithotripsy or percutaneous nephrolithotomy. A multi-disciplinary approach is necessary, and this review examines the status of modern stone therapy and the contribution of the radiology department.

Drainage↗
PubMed2003

The diagnostic contribution of the frontal lumbar spine radiograph in community referred low back pain--a prospective study of 1030 patients.

AIM: The diagnostic contribution of the anteroposterior (AP) view was studied to assess whether this view could be omitted safely, thus reducing the radiation burden received by patients undergoing lumbar spine radiography. MATERIALS AND METHODS: Prospective analysis of 1030 consecutive referrals for lumbar spine radiography from general practice. RESULTS: In the majority of cases (90.5%) the AP view was non-contributory. In 4.2% the diagnosis was strengthened and it was altered in 4.6%. However, in the latter group only 1.3% of the total were considered significant alterations. These were cases of possible, but not definite, pars defects and sacroiliitis. Specific important conditions such as infection, malignancy and benign tumours were not missed on the lateral view alone, in our study population. The radiation burden is reduced by 75% by omitting the AP view. CONCLUSION: A single lateral view is an adequate examination, with the proviso that sacroiliac joint disease is not assessed on this view and some pars defects and facet joint degenerative changes may be overlooked. The radiation protection gains are considerable. A single lateral lumbar view is now our routine practice unless sacroiliitis is a specific clinical concern.

Adolescent↗
PubMed2003

Doppler ultrasound for detection of renal transplant artery stenosis-threshold peak systolic velocity needs to be higher in a low-risk or surveillance population.

AIMS: To establish the ideal threshold arterial velocity for the diagnosis of renal transplant artery stenosis in a surveillance population with a low pre-test probability of stenosis. METHODS: Retrospective review of Doppler ultrasound, angiographic and clinical outcome data of patients transplanted over a 3-year period. Data used to calculate sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) for various threshold peak systolic velocity values. RESULTS: Of 144 patients transplanted, full data were available in 117 cases. Five cases had renal transplant artery stenosis-incidence 4.2% [stenosis identified at a mean of 6.5 months (range 2-10 months)]. All five cases had a significant arterial pressure gradient across the narrowing and underwent angioplasty. Threshold peak systolic velocity of > or =2.5 m/s is not ideal [specificity=79% (CI 65-82%), PPV=18% (CI 6-32%), NPV=100% (CI 94-100%)], subjecting many patients to unnecessary angiography-8/117 (6%) in our population. Comparable values if the threshold is set at > or =3.0 m/s are 93% (CI 77-96%), 33% (CI 7-44%) and 99% (CI 93-100%), respectively. The clinical outcome of all patients was satisfactory, with no unexplained graft failures or loss. CONCLUSIONS: In a surveillance population with a low pre-test probability of stenosis, absolute renal artery velocity > or =2.5 m/s is a limited surrogate marker for significant renal artery stenosis. The false-positive rate is high, and > or =3.0 m/s is a better choice which will halve the number of patients enduring unnecessary angiography. Close clinical follow-up of patients in the 2.5-3.0 m/s range, with repeat Doppler ultrasound if necessary, will identify the test false-negatives.

Adult↗
PubMed2003

Morbidity of transrectal ultrasonography-guided prostate biopsies in patients after the continued use of low-dose aspirin.

OBJECTIVE: To determine whether low-dose aspirin increases morbidity after transrectal ultrasonography-guided sextant prostate biopsy. PATIENTS AND METHODS: In a single-centre prospective cohort study of 200 patients who underwent sextant prostate biopsies, those routinely taking low-dose aspirin were encouraged to continue to do so before and after biopsy. The morbidity in each case was assessed using a standardized questionnaire that patients completed in the 7 days after biopsy. The presence of haematuria, rectal bleeding and haematospermia were recorded. The questionnaire also directed the patient to record fevers, use of analgesia and any further treatment received. RESULTS: In all, 36 patients took aspirin whilst the other 141 did not. There were no major complications in either group. Of the patients on aspirin, 20 (56%) had haematuria, compared with 83 (59%) of those not taking aspirin (difference 3%, 95% confidence interval, CI, -15 to 21). Overall bleeding (haematuria, rectal bleeding and haematospermia) occurred in 22 patients (61%) of the aspirin group and 105 (74%) of the other group (difference 13%, 95% CI -4 to 31). Comparisons of other morbidities between the groups are also discussed. CONCLUSIONS: There was no statistically significant difference in the incidence of haematuria or overall bleeding after biopsy between the groups. There is no evidence that aspirin needs to be discontinued before sextant prostate biopsy.

Aspirin↗
PubMed2003

Demonstration of renal arterial anatomy and tumour neovascularity for vascular mapping of renal cell carcinoma: the value of CO2 angiography.

The aim of this study was to compare the efficacy of CO(2) angiography with that of iodinated contrast angiography for vascular mapping prior to partial nephrectomy for presumed renal cell carcinoma. 13 consecutive patients were studied and all patients underwent selective renal angiography using both CO(2) and iodinated contrast medium. Digitally subtracted images were acquired and compared. Seven male and six female patients, with a median age of 58 years (range 46-74 years), were examined. On comparing images the main renal artery was visualized in all cases with both contrast agents. The segmental vessels were seen in 7 of 13 CO(2) studies and 12 of 13 iodinated contrast studies. CO(2) was also inferior in the depiction of tumour circulation, showing it in 4 of 13 cases compared with 9 of 13 cases using iodinated contrast. It therefore appears that CO(2) angiography offers no diagnostic advantage and is also inferior to iodinated contrast angiography in the pre-operative vascular mapping of renal tumours.

Aged↗
PubMed2002

Improving glandular coverage during prostate biopsy using a long-core needle: technical performance of an end-cutting needle.

OBJECTIVE: To compare the technical performance of a 33-mm core-length biopsy needle with that of the standard 18 mm needle, as many prostate cancers are isoechoic and in large prostates the tissue coverage with the 18 mm needle is inadequate. PATIENTS AND METHODS: A 33-mm core length BioPince VSL disposable needle (Amedic, Sweden) and a standard TruCut 18 mm needle (Medical Device Technology Inc., FL, USA) were used to take prostatic biopsies in two groups of 15 patients. The following variables were assessed for each group: mean core length, core quality, capsular coverage (one or both capsules within the specimen), and side-effects in the first week after biopsy (for the BioPince group, surveyed using a self-completed questionnaire). The results were compared with historical data from a group of 30 patients biopsied using the standard needle. RESULTS: For the BioPince and standard groups the mean (sd) core length was 19.4 (8.9) and 14.9 (5.1) mm, respectively. Four needles in the BioPince group failed to capture a sample, requiring needle replacement. The samples were fragmented in 15 of 90 (17%) and 41 of 90 (46%) biopsies in the BioPince and standard groups, respectively (P < 0.05). Specimens had both capsules present in five of 90 (6%) and four of 90 (4%), respectively. Within 7 days minor bleeding was the most common side-effect. Pain after biopsy was the only symptom showing a significant difference between the groups, at six of 15 and none (P = 0.001), respectively. The incidence of haematuria, haematospermia and rectal bleeding was similar in the two groups (P > 0.05), but fever more common (three vs none) in the BioPince group (P = 0.06). CONCLUSION: When set at a 33-mm stroke length, the BioPince needle increases the mean core length by 30%, with less fragmentation than a standard 18 mm needle. However, it has a significant failure rate for capture (27% needle replacement rate), slightly greater morbidity (pain and possibly fever) and shows no advantage in capsular coverage. Therefore, there are shortcomings with this end-cutting needle when used at 33 mm core length.

Aged↗