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Manoj Monga

Publications and source records attributed to Manoj Monga.

At least 37 records · Page 2Linked to original sources
PubMed2004

Forearm compression by laparoscopic hand-assist devices.

BACKGROUND AND PURPOSE: Laparoscopic hand-assist devices have facilitated the broad application and acceptance of laparoscopy in urology and other surgical fields. This study evaluated forearm compression by these devices. MATERIALS AND METHODS: Five commercially available hand-assist devices were tested (Gelport, Intromit, PneumoSleeve, Handport, LapDisc). In three surgeons using a porcine model, compressive forces were measured along the paths of the median and ulnar nerves at the point of maximum proximal forearm circumference using FlexiForce A101 sensors. Glove size for all three surgeons was 7 1/2; however, the maximum forearm circumference ranged from 26 to 33 cm. The hand-assist devices were placed in pigs after skin and fascial incision (9 cm), and the insufflation pressure was set at 18 mm Hg. Surgeons subjectively rated the ease of device insertion and hand insertion, degree of forearm compression, and the development of paresthesias. RESULTS: The LapDisc was rated superior with regard to insertion. The Gelport was rated superior for hand insertion and removal; however, moderate to severe forearm compression and paresthesias were reported. The maximum forearm compression forces were highest with the LapDisc (97 mm Hg) and the Gelport (78 mm Hg) and lowest with the Handport (33 mm Hg). CONCLUSION: The choice of hand-assist device is dependent on its ease of use, efficacy at maintaining insufflation, and effect on the surgeon's performance and fatigue. The impact of forearm compression should be considered in the selection of the hand-assist device and in the development of new devices.

Animals↗
PubMed2004

Radial dilation force of tipless and helical stone baskets.

PURPOSE: To evaluate one aspect of tipless and helical stone basket function that is critical for ureteral stone extraction: the radial-dilation force. MATERIALS AND METHODS: Nine commercially available tipless baskets and five commercially available helical stone baskets were tested. Two Teflon blocks were positioned with the lower block sitting on a digital scale and the upper block secured to a plastic frame and base. A 0.01-inch gap was maintained between the blocks using a digital micrometer. Alignment pins secured the position of the lower block in relation to the upper block. A 4-mm cylindrical hole was drilled through the center of the block interface, and each basket was passed through the hole and opened to its fully extended length. The basket was then slowly retracted through the hole, and the maximum force reading was recorded. Twenty repetitions were performed for each basket. RESULTS: Of the tipless baskets > or =3.0F, the Cook N-Circle 3.2F provided the best radial dilation (24.7 +/- 0.4 g). For tipless baskets <3.0F, the Sacred Heart Vantage 2.4F provided the best radial dilation (19.6 +/- 0.8 g). Of the helical baskets, the Sacred Heart Hercules provided the most radial dilation (102 +/- 12.1 g) followed by the Cook N-Force (71.8 +/- 4.3 g). CONCLUSION: The radial-dilation force of tipless and helical stone baskets differs significantly among baskets and may impact stone extraction performance in the ureter.

Equipment Design↗
PubMed2004

Accessory instrumentation for ureteroscopy.

PURPOSE OF REVIEW: The use of ureteroscopy for diagnostic and therapeutic applications has evolved rapidly over the past 5 years. The purpose of this review is to discuss recent advances in instrumentation for rigid and flexible ureteroscopy. RECENT FINDINGS: Advances in accessory instrumentation can be divided into improvements in ureteral access, irrigation, intracorporeal lithotripsy, and stone extraction. By evaluating in-vitro and clinical evaluations of accessory instrumentation, one can identify specific products that may facilitate a positive ureteroscopic outcome. SUMMARY: Preoperative preparation is the best predictor of positive outcome after ureteroscope. The cornerstone to preoperative preparation is the proper selection of accessory instrumentation. There is no greater frustration than to see the target but be unable to address it.

Equipment Design↗
PubMed2004

Residency training in percutaneous renal access: does it affect urological practice?

PURPOSE: We evaluated the impact of residency training in percutaneous renal access on subsequent urological practice. MATERIALS AND METHODS: Surveys evaluating practice and training in percutaneous renal access were mailed to residents who graduated between 1981 and 2001. A statistical analysis was performed to determine the effect of percutaneous access training on current practice patterns in percutaneous renal procedures. A subgroup analysis was conducted for graduates with more than 10 years after residency. RESULTS: Responses were received from 37 of 48 surveys mailed (77%) and 35 surveys were eligible for analysis. A total of 92% of urologists trained in percutaneous access currently perform percutaneous surgical procedures compared to only 33% of those untrained (p <0.001). Urologists trained in access perform a mean of 14.0 percutaneous renal procedures annually while those untrained perform 3.3 procedures (p = 0.02). Only 27% of urologists trained in percutaneous access continue to perform percutaneous renal access compared to 11% of those untrained (p = 0.33). A subset analysis of urologists trained more than 10 years ago shows similar results. The primary reasons stated for not performing their own access are that the radiologist has better equipment (61%) or skills (44%), or obtaining access requires extra time (50%). CONCLUSIONS: This study suggests a relationship between training in percutaneous renal access and subsequent use of percutaneous renal procedures in the urologist's practice. Emphasis should be placed on providing continuing education opportunities to maintain competency in this important technique.

Clinical Competence↗
PubMed2004

Percutaneous renal stone extraction: in vitro study of retrieval devices.

PURPOSE: Traditionally, percutaneous stone extraction has relied on the use of 2-prong and 3-prong graspers, which are prone to causing trauma to the urothelium. We evaluate the efficiency of stone removal with a novel tipless stone basket designed specifically for percutaneous procedures. MATERIALS AND METHODS: A 3, 5 and 8 mm human calculus were placed in the calix of a percutaneous renal model. A 26Fr Storz nephroscope (27093B, Storz Medical AG, Kreuzlingen, Switzerland) was inserted through a 30Fr Amplatz sheath into the model with camera input from a Storz telecam SL-NTSC feeding to a 20-inch Sony Triniton monitor (Sony Corp of America, New York, New York). Operators were randomized to start stone extraction with a Storz 3-prong grasper (27090RB) or a Cook 12Fr Perc-NCircle (38 cm) (Cook Urological, Inc., Indianapolis, Indiana). Subsequent testing alternated between the 2 devices until 10 extraction attempts were conducted with each device. Time to extraction of all 3 calculi and number of inadvertent withdrawals of the sheath were recorded. Three experienced operators tested each device. RESULTS: Stone extraction times were shorter with the Cook Perc-NCircle than the 3-prong grasper for all operators. Mean time for stone extraction was 25.3 +/- 11.2 seconds for the Perc-NCircle compared to 35.1 +/- 18.5 seconds for the 3-prong grasper (p = 0.016). Loss of access by inadvertent removal of the Amplatz sheath occurred in 53% of the attempts with the 3-prong grasper compared to 7% of attempts with the Perc-NCircle. CONCLUSIONS: The Cook Perc-NCircle facilitates a more expeditious approach to percutaneous stone removal with less risk of sheath withdrawal.

Equipment Design↗
PubMed2004

Comparison of nitinol tipless stone baskets in an in vitro caliceal model.

PURPOSE: Tipless stone baskets facilitate caliceal calculi extraction during flexible ureteroscopy. We evaluated the stone capture rate of 9 commercially available tipless stone baskets in an in vitro model using novice and expert operators. MATERIALS AND METHODS: The Microvasive Zerotip (2.4Fr, 3.0Fr), Cook N-Circle (2.2Fr, 3.0Fr, 3.2Fr), Bard Dimension (3.0Fr, Sacred Heart Medical Halo (1.9Fr), Vantage (1.9Fr) and Circon-ACMI Sur-Catch-NT (3.0Fr) were tested by 3 novice and 3 experienced basket operators. Each operator performed stone extraction of 2, 5 and 8 mm calculi (size determined by digital caliper with 3 repetitions of each basket. The time to extraction of the calculus from a convex based test tube caliceal model was recorded. Statistical analysis was performed using repeated measures ANOVA and Fisher's pairwise comparisons. RESULTS: After a learning curve of 27 basket retrievals, there was no significant difference in stone capture times between novice (38 +/- 54 seconds) and expert operators (32 +/- 49 seconds, p = 0.174). For total stone capture (all sizes) the Sacred Heart Halo resulted in the most rapid stone extraction (17 +/- 14 seconds) by novices and experts, while the Sur-Catch NT resulted in the slowest stone extraction (78 +/- 90, seconds, p = 0.001). The Halo (14 +/- 9 seconds) and Vantage (19 +/- 12 seconds) baskets were significantly faster for 2 mm calculi than the N-Circle (73 +/- 60 seconds, p = 0.006), Sur-Catch (169 +/- 85 seconds, p = 0.0005) and Dimension (73 +/- 70 seconds, p = 0.017). The Zerotip functioned well for 2 mm calculi in the hands of expert operators (15 +/- 9 seconds) but not novice operators (94 +/- 95 seconds). The Sur-Catch NT was significantly slower for 2 mm calculi than the N-Circle (p = 0.01), Dimension (p =.03), Halo (p =.0005), Vantage (p =.001) and Zerotip (p =.002). For 5 mm calculi the Halo was superior (12 +/- 8 seconds), while the Zerotip were superior for 8 mm calculi (8 +/- 3 seconds) compared to the N-Circle (23 +/- 28 seconds, p = 0.026), Halo (26 +/- 18 seconds, p = 0.021) and Vantage (23 +/- 15 seconds, p = 0.006). CONCLUSIONS: The Sacred Heart Halo and Vantage baskets resulted in the most expeditious stone extraction, especially for 2 to 5 mm calculi while the Microvasive Zerotip was optimal for 8 mm calculi. The Sur-Catch NT had the slowest stone capture rate for all stone sizes. Caliceal models of stone basketing may be useful to train novice urology residents and nursing assistants.

Alloys↗
PubMed2004

Prospective randomized comparison of 2 ureteral access sheaths during flexible retrograde ureteroscopy.

PURPOSE: While the use of ureteral access sheaths facilitates flexible ureteroscopy, buckling or kinking of the device may preclude its successful application. We evaluate the ability of 2 hydrophilic coated ureteral access sheaths to obtain and maintain access to the upper collecting system. MATERIALS AND METHODS: A total of 54 flexible ureteroscopy procedures were randomized to use of the 12/15Fr Applied Access Forte XE (Applied Medical, Rancho Santa Margarita, California) or the 12/14Fr Cook Flexor (Cook Urological, Spencer, Indiana) access sheaths. Device failure was defined as buckling of the sheath that prevented adequate placement, kinking of the sheath after removal of the obturator or difficulty in passing instruments through the sheath. The ease of placement, instrument passage and stone extraction was scored from poor (1) to excellent (4). Fisher's exact test and Mann-Whitney tests were used for statistical comparisons. RESULTS: No patient required ureteral balloon dilation. There was no significant difference between the groups in regard to preoperative stenting (34% and 31%, p = 1.00) or rigid ureteroscopy before sheath placement (32% and 25%, p = 0.751). The device failure rate was 44% for the Applied sheath and 0% for the Cook sheath (p <0.001). Failures with the Applied sheath included buckling (25%), kinking (25%) and difficulty passing instruments (13%). The Cook sheath was rated superior with regard to ease of placement (3.89 vs 3.00, p = 0.001), ease of instrument passage (3.97 vs 3.29, p = 0.001) and ease of stone extraction (3.74 vs 3.00, p = 0.023). CONCLUSIONS: The performance of the Cook Flexor sheath was superior with regard to overall failure and ease of use.

Adult↗
PubMed2004

Transurethral microwave thermotherapy vs transurethral resection for treating benign prostatic hyperplasia: a systematic review.

OBJECTIVE: To conduct a systematic review of randomized controlled trials evaluating the efficacy and safety of transurethral microwave thermotherapy (TUMT) compared with transurethral resection of the prostate (TURP) in treating men with symptomatic benign prostatic hyperplasia (BPH). METHODS: We searched Medline, the Cochrane Library and reference lists of retrieved studies to identify randomized trials of >/= 6 months duration with >/= 10 patients in each treatment arm. Data were extracted on study design, patient and treatment characteristics, urinary symptoms, urinary flow, adverse events and repeat treatment for BPH. RESULTS: Six studies were evaluated, involving 540 patients. The mean age (67.8 years), baseline symptom score (19.5), and peak urinary flow (PUF, 8.6 mL/s) did not differ by treatment group. The pooled mean urinary symptom score decreased by 65% with TUMT and 77% with TURP. The weighted mean (95% confidence interval) difference for the symptom score at the follow-up was -1.83 (-3.09 to -0.58) points, favouring TURP. The pooled mean PUF increased by 70% with TUMT and 119% with TURP. The weighted mean difference for the PUF at the follow-up was 5.37 (4.22-6.51) mL/s, favouring TURP. Retrograde ejaculation (57.6% vs 22.2%), transfusions (5.7% vs 0%) and re-treatment for strictures (relative hazard 9.76) were all significantly more common after TURP, but re-treatment for BPH was significantly more common after TUMT (relative hazard 10.0). CONCLUSIONS: TUMT techniques are effective and safe short-term alternatives to TURP for treating BPH. However, TURP provided greater symptom and urinary flow improvements and fewer subsequent BPH treatments than TUMT.

Aged↗
PubMed2003

Curcumin: a potential vaginal contraceptive.

The purpose of this investigation was to evaluate the sperm-immobilizing effects of curcumin, a plant-derived diferuloylmethane compound. Washed human healthy sperm were suspended in Ham's F10 and exposed to varying concentrations of curcumin. Sperm motility was evaluated and changes in sperm mitochondrial transmembrane potential (MTP) was quantified by flow cytometry. Incubation of normal human sperm with curcumin resulted in a dose- and time-dependent loss of sperm motility. At lower concentrations (30 g/mL), curcumin produced a significant (20%) decrease in sperm motility within 30 min without significant effects on sperm viability. An instantaneous (>50%) loss of sperm motility was observed with higher concentrations (300 g/mL) of curcumin and a total loss of sperm motility was achieved within 60 min. A significant reduction in sperm MTP was found with all doses of curcumin tested. Our results indicate that curcumin has a selective sperm-immobilizing effect, in addition to a previously studied anti-HIV property. This compound may have potential clinical applications as a novel intravaginal spermicidal agent for contraception and HIV prevention.

Administration, Intravaginal↗
PubMed2003

Intravesical ethanol test: an ineffective measure of bladder hyperpermeability.

OBJECTIVES: To evaluate the intravesical ethanol test as a quantitative measure of bladder hyperpermeability in patients with interstitial cystitis. METHODS: Patients with a clinical diagnosis of interstitial cystitis and a positive result on the Parsons potassium test were enrolled in the study. The intravesical ethanol test was conducted after completion of the Parsons potassium test. Dose escalation (10% to 20% ethanol) was performed in an attempt to achieve detectable levels of ethanol. Breathalyzer data were recorded in 5-minute intervals for 30 minutes using a calibrated Intox Breathalyzer Model IV Alcosensor. The bladder was then drained, and volume recovered was recorded. The breathalyzer data were recorded for an additional 30 minutes after removal of the catheter at 5-minute intervals. RESULTS: The 3 patients studied demonstrated significant qualitative evidence of bladder hyperpermeability, with pain and urgency scores ranging from 4 to 5 on the Parsons potassium test. No detectable levels of ethanol were identified in any of the 3 patients after the intravesical ethanol test, with up to 50 mL of 20% ethanol instilled for 30 minutes. Intravesical ethanol instillation was not associated with significant pain or irritative voiding symptoms. CONCLUSIONS: The intravesical ethanol test did not prove to be a useful clinical adjunct in the diagnosis and management of interstitial cystitis. The evaluation of higher concentrations of ethanol may be warranted.

Administration, Intravesical↗
PubMed2003

Characterization of intrapelvic pressure during ureteropyeloscopy with ureteral access sheaths.

OBJECTIVES: To evaluate the impact of the ureteral access sheath on intrarenal pressures during flexible ureteroscopy in light of the recent resurgence in their use. As such, using human cadaveric kidneys, we studied changes in intrarenal pressure in response to continuous irrigation at different pressures with and without access sheaths of various sizes and lengths. METHODS: This study was performed using seven cadaveric kidneys. In three kidneys the study was done in situ with a 7.5F flexible ureteroscope (URS) passed by itself and then passed through a 10/12F sheath (35 and 55 cm in length), whereas, in four kidneys, due to narrowing of the intramural ureter, the study was done ex vivo using the unsheathed URS and then passing the 7.5F flexible URS via the 10/12F, 12/14F, and 14/16F sheaths (all 35 cm in length). A 10F Cope loop pyelostomy was placed to measure intrapelvic renal pressure. Three sets of 3-minute readings (ie, flow and intrarenal pressure) were taken with the tip of the URS at the distal ureter, middle ureter, and renal pelvis (just above the ureteropelvic junction); the entire process was done at three different irrigant pressure settings: 50, 100, and 200 cm H(2)O. Irrigant flow and intrarenal pressures were measured at all three settings using the URS passed without a sheath and then with the URS passed through the various sheaths positioned at the distal ureter, middle ureter, and renal pelvis. RESULTS: With all of the sheaths, intrapelvic pressure remained low (less than 30 cm H(2)O), and there was a 35% to 80% increase in irrigant flow versus the control unsheathed URS. With the sheath in place, the majority of the irrigant drained alongside the URS and out the sheath. Flow and pressure with the 12/14F sheath were equivalent to the 14/16F sheath. CONCLUSIONS: The 12/14F access sheath provides for maximum flow of irrigant while maintaining a low intrarenal pelvic pressure. Even with an irrigation pressure of 200 cm H(2)O, renal pelvic pressure remained below 20 cm H(2)O.

Equipment Design↗
PubMed2003

Evaluation of overall costs of currently available small flexible ureteroscopes.

OBJECTIVES: To perform a meta-analysis of the currently available data regarding the durability of flexible ureteroscopes to establish cost estimates for the purchase and use of five currently available, smaller than 9F, ureteroscopes. Healthcare costs have become increasingly germane to the determination of disease management strategies. Improved ureteroscope technology has expanded the role of these instruments. However, the initial purchase costs and high maintenance costs have become problematic with these fragile instruments. METHODS: Ureteroscope durability data on the Storz 11274AA, Olympus URF-P3, Wolf 7325.172, ACMI AUR-7, and ACMI DUR-8 were collected from three prior studies. Combining the durability data and cost data regarding the initial purchase price and maintenance costs of these instruments, we calculated the overall costs associated with the use of each of the ureteroscopes for 25, 50, 75, and 100 cases during the first year (warranties included) and with subsequent use. RESULTS: The variability in the costs associated with the use of the currently available smaller than 9F ureteroscopes was significant. The initial instrument purchase price, durability, repair costs, and associated warranties all contributed to large discrepancies in the cost of performing ureteroscopy. In this model, during the first year of ownership, the projected cost of performing 100 ureteroscopic cases varied by a difference of 95% depending on the ureteroscope used. CONCLUSIONS: Physicians and institutions that perform ureteroscopy should strongly consider the purchase price, durability, repair cost, and associated warranties before the purchase of small flexible ureteroscopes.

Costs and Cost Analysis↗
PubMed2003

Intraoperative mapping of renal lymphatic drainage: technique and application in a porcine model.

BACKGROUND AND PURPOSE: The use of lymphadenectomy in renal-cell carcinoma (RCC) is controversial. Proponents argue that lymphadenectomy improves survival, whereas opponents challenge the procedure on the basis of its morbidity and the variable lymphatic drainage of the kidney. Intraoperative gamma probes have been used to guide resection of radiolabeled sentinel nodes in cancers of the breast, penis, and head and neck and in melanoma. Our goal in applying this technique to RCC is to improve detection and to limit sampling of lymph nodes during lymphadenectomy. This preliminary study in a porcine model evaluated the feasibility and transit time of radiolabeled tracer injected into the kidney. MATERIALS AND METHODS: Data were collected on four 40-kg Yorkshire pigs. The right kidney was exposed through a flank incision. Using both blue dye and technetium-99m, mapping and resection of the sentinel lymph nodes was performed with the assistance of an intraoperative gamma probe (Neoprobe). Remote cervical lymph nodes were utilized as controls. Vascular counts along the carotid vessels were obtained to confirm that the radioisotope was not being dispersed systemically. RESULTS: Within 10 minutes of renal injection of the tracer, excised sentinel lymph nodes demonstrated significant radioactive counts compared with controls. Vascular counts confirmed that radioisotope tracer did not enter the venous circulation. CONCLUSIONS: Sentinel lymph node sampling using a gamma probe and blue dye appears to be feasible in the porcine kidney. Further studies using this technique in humans will evaluate the impact of selective lymphadenectomy on survival in RCC.

Animals↗
PubMed2003

Is there a role for pentosan polysulfate in the prevention of calcium oxalate stones?

The clinical role for pentosan polysulfate (PPS) in the prevention of calcium oxalate urolithiasis is not known. Crystallization and aggregation are important steps in calcium oxalate stone formation, and PPS has been shown to inhibit these steps, both in vitro and in vivo. In addition, PPS has a role in repairing injured urothelium and inhibiting adhesion to epithelial defects. A randomized double-blind placebo-controlled study appears warranted to assess the utility of PPS in the prevention of recurrent calcium oxalate stones.

Administration, Oral↗
PubMed2003

Surgical management of the calyceal diverticulum.

PURPOSE OF REVIEW: The management of calyceal diverticulum has evolved from an open surgical approach to a minimally invasive approach. Currently, the percutaneous, ureteroscopic and laparoscopic techniques are recommended by individual investigators. Recent studies have helped establish patient selection criteria for each of the above procedures. This review will discuss technique and results and suggest a treatment algorithm for the patient with a symptomatic calyceal diverticulum. RECENT FINDINGS: Excellent long-term success has been reported with all three minimally invasive modalities. Percutaneous ablation of the calyceal diverticulum is the most established minimally invasive technique for this disorder. A direct puncture into the calyceal diverticulum is recommended. Limitations exist primarily for an anteriorly located diverticulum. In this situation, if the diverticulum is in a superior anterior calyx, a ureteroscopic approach is recommended while if the diverticulum is in a middle or lower pole calyx, a laparoscopic approach is recommended. SUMMARY: This review suggests that experience and expertise in percutaneous, ureteroscopic and laparoscopic techniques provide the urologist with the best opportunity to individualize treatment approach based on location and size of the diverticulum. A treatment algorithm based on these parameters may be helpful in patient counseling and decision-making.

Clinical Trials as Topic↗
PubMed2003

Laboratory evaluations of erectile dysfunction: an evidence based approach.

PURPOSE: We evaluate the prevalence of laboratory abnormalities in men presenting for initial evaluation and therapy of erectile dysfunction. MATERIALS AND METHODS: The computerized charts of men receiving treatment for erectile dysfunction from 1987 to 2002 were retrospectively reviewed. We pooled laboratory data for 3,547 men with erectile dysfunction to assess the prevalence of laboratory abnormalities. Values of the common laboratory screening tests for erectile dysfunction were recorded for testosterone, prolactin, luteinizing hormone, thyroid-stimulating hormone, hemoglobin A(Ic), prostate specific antigen, hemoglobin, cholesterol and creatinine. RESULTS: Of those patients evaluated 18.7% had low testosterone, 4.6% had increased prolactin, 14.6% had abnormal luteinizing hormone, 4.0% had increased thyroid-stimulating hormone, 8.3% had increased prostate specific antigen, 26.5% had anemia and 11.9% tested had renal insufficiency. A high percentage of patients presenting with a primary complaint of erectile dysfunction had increased hemoglobin A(Ic) and total serum cholesterol levels (52.9% and 48.4%, respectively). CONCLUSIONS: An evidence based approach to standardization of laboratory evaluations for men presenting with erectile dysfunction is recommended. Laboratory screening should be directed to identify those risk factors that may benefit from lifestyle modification and pharmacological intervention.

Aged↗