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Featured researches published by P.N. Dogra.


Urology | 2001

Severely encrusted polyurethane ureteral stents: Management and analysis of potential risk factors

Iqbal Singh; N.P. Gupta; Ashok K. Hemal; Monish Aron; Amlesh Seth; P.N. Dogra

OBJECTIVES To review the management of heavily encrusted and stuck JJ ureteral stents. We report our experience and review current published reports in managing heavily encrusted and stuck JJ stents, the guidelines for management, and the prevention of such problems. METHODS We reviewed our stent records from January 1994 to December 2000 and analyzed our stent complications and their final outcome. Fifteen patients had heavily encrusted and stuck stents. Of these, 14 were encountered in patients with a sizable stone burden (400 to 650 mm(2)) and 1 occurred in a patient with malignant ureteral obstruction. Sandwich combinations of multiple extracorporeal shock wave lithotripsy/traction and endourologic procedures were used to render them stone and stent free. The stent was examined and the encrustation was analyzed by x-ray crystallography. RESULTS Of 15 patients, 13 were available for evaluations; 1 patient was lost to follow-up and 1 patient died. The average stone burden was 625 mm(2). The encrustation was localized to the upper end in eight and to the lower and upper end in three. In 4 cases, the entire stent was encrusted, and the lumen was occluded in 12. All 13 patients with stuck, fragmented, and encrusted stents were rendered stone and stent free; 2 of the 13 had clinically insignificant residual stones (less than 2 mm). Calcium phosphate and monohydrate stones were the most commonly encountered stone encrustations. CONCLUSIONS Stent encrustation is one of the most serious complications of polyurethane JJ stents. Multimodal endourology should form the cornerstone of therapy for heavily encrusted stuck stents. It is important to maintain an efficient computerized stent log under the direct supervision of a physician. Patients with probable risk factors should be monitored even more frequently to avoid mishaps and morbidity.


Urology | 2002

Post-ESWL, clinically insignificant residual stones: reality or myth?

Anurag Khaitan; Narmada P. Gupta; Ashok K. Hemal; P.N. Dogra; Amlesh Seth; Monish Aron

OBJECTIVES To assess the significance of asymptomatic residual stone fragments of less than 4 mm (clinically insignificant residual fragments [CIRFs]) after extracorporeal shock wave lithotripsy (ESWL). METHODS Eighty-one patients were followed up for 6 to 60 months (mean 15) after ESWL to determine the fate of the CIRFs. RESULTS Of the 81 patients, 6 were lost to follow-up, leaving 75 patients. During follow-up, fragments passed spontaneously in 18 patients, remained stable in 13 patients, and became clinically significant in 44 patients who developed one or more complications. For the latter patients, repeated ESWL was done in 16, percutaneous nephrolithotomy in 3, and ureteroscopic stone removal in 4 patients. The remaining 21 patients were treated conservatively with analgesics. We found that 53% of the CIRFs located in the pelvis passed spontaneously, and most of the CIRFs in caliceal location became clinically significant. Also, as the stone burden and number of stone fragments increased, the risk of CIRFs becoming clinically significant increased. The outcome was the same whether a metabolic abnormality was present or not, provided the patient received appropriate treatment. The clearance rate was highest in the first 6 months. Finally, as the duration of follow-up increased, the rate of complications increased. CONCLUSIONS Patients with residual stones after ESWL require close follow-up and timely adjuvant therapy. As the number and size of residual fragments increased, the risk of complications increased. A pelvic location was a favorable factor for spontaneous passage. Metabolic defects, if treated adequately, did not increase the regrowth rate. Although the complete clearance rate of CIRFs with repeated ESWL was lower than for the operative interventions, most patients improved with this modality.


Urologia Internationalis | 1999

Cutaneous Metastases in Renal Cell Carcinoma

L.N. Dorairajan; Ashok K. Hemal; Monish Aron; T.P. Rajeev; Manju Nair; Amlesh Seth; P.N. Dogra; N.P. Gupta

Cutaneous metastasis from renal cell carcinoma is believed to be rare. We present our experience with 10 (3.3%) cases seen in the last 12 years among 306 cases of renal adenocarcinoma treated at our center. There were 9 males and 1 female. Age ranged from 30 to 65 years (average 45 years). 5 patients had skin metastases at the time of presentation (stage IV). In one of them the skin nodule, rather than urologic symptoms, was the presenting complaint. 5 patients presented with skin metastasis during follow-up after nephrectomy. The average time to skin metastasis was 51 months for patients in stage I and 13 months in stage IIIb. The scalp was the most common site of metastasis followed by chest and abdomen. 90% of patients had secondaries in at least one other site, most commonly in lungs (4 cases) and bones (5 cases). 4 patients were treated with interferon-α 6 MIU, subcutaneously, three times a week for varying periods from 3 to 4 months but there was no response. In conclusion, cutaneous secondaries from RCC, though uncommon, are not very rare. A few patients may present with a skin mass before detection of the renal tumor. Patients with low-stage disease at presentation may also develop cutaneous secondaries, therefore a prolonged follow-up is required. The commonest site for cutaneous metastasis from RCC is the scalp and face. Most patients had at least one other site of systemic metastasis, hence they were not candidates for curative therapy. Interferon therapy was not helpful. Mean survival after detection of cutaneous metastasis was 7 months.


International Journal of Urology | 2005

Spectrum of stone composition : structural analysis of 1050 upper urinary tract calculi from northern India

M.S. Ansari; Narmada P. Gupta; Ashok K. Hemal; P.N. Dogra; Amlesh Seth; Monish Aron; Tej P Singh

Abstract Background:  The purpose of the present paper was to study the spectrum of stone composition of upper urinary tract calculi by X‐ray diffraction crystallography technique, in patients managed at All India Institute of Medical Sciences.


BJUI | 2004

Dorsal buccal mucosal graft urethroplasty by a ventral sagittal urethrotomy and minimal-access perineal approach for anterior urethral stricture.

N.P. Gupta; M.S. Ansari; P.N. Dogra; S. Tandon

In the mini‐review section of this issue, the use of buccal mucosal grafts in urethroplasty is described and the authors raise the point that it may now be the ‘reference’ standard. In this section, authors from New Dehli describe these technique of anterior urethral reconstruction for long strictures using buccal mucosal grafts. Their rather novel approach is of interest, and they report good results with up to 16 months of follow‐up.


Urology | 2001

Impact of power index, hydroureteronephrosis, stone size, and composition on the efficacy of in situ boosted ESWL for primary proximal ureteral calculi.

Iqbal Singh; Narmada P. Gupta; Ashok K. Hemal; P.N. Dogra; M.S. Ansari; Amlesh Seth; Monish Aron

OBJECTIVES The efficacy, safety, feasibility, and outcome of in situ treatment applied to select proximal ureteral calculi was assessed and analyzed with a view to avoiding auxiliary interventions and providing high clearance rates in the shortest possible time. We studied the impact of several clinically important variables, including power index, degree of hydroureteronephrosis (HDUN), stone size, and composition on the efficacy of sequential in situ boosted extracorporeal shock wave lithotripsy (ESWL) in a select group. The power index requirement for the in situ boosted protocol and the impact of the stone size/composition, degree of HDUN, and clearance rates were also analyzed. METHODS An in situ (no instrumentation) boosted protocol was applied to 130 primary unimpacted proximal ureteral calculi with no prior intervention. A typical session with the Siemens Lithostar Plus comprised 3000 shock waves, in installments of 500, deployed at a power setting of 1 to 4 kV with a gradual stepwise escalation. Sequential boosted additional sessions of ESWL were administered on days 2, 7, and 14, tailored to the degree of fragmentation, clearance status, and amount of residual stone bulk. Several parameters (shock waves, kilovolts used, fluoroscopy time, number of sessions, stone size, composition, fragmentation, clearance, and HDUN) were recorded and the results analyzed statistically. RESULTS The results were excellent in 83.8%, with a mean duration to complete clearance of 11.3 days. In situ ESWL failed in 7.69%, and the auxiliary intervention rate was 10.7%. Pre-ESWL HDUN was present in 78.3%, the mean power index was 184.6/session/case, and the average stone burden was 8.9 mm(2). Calcium oxalate monohydrate was the most common stone (56%). Renal colic was the most common side effect observed. The power index, fragmentation at the first session, and stone size were found to be the most favorable significant variables affecting stone clearance. The degree of HDUN, number of sessions, and stone composition did not significantly impact the clearance rates. CONCLUSIONS In situ boosted ESWL should be the first-line therapeutic modality in select unimpacted primary proximal ureteral stones.


The Journal of Urology | 1998

MANAGEMENT OF OBLITERATIVE POSTTRAUMATIC POSTERIOR URETHRAL STRICTURES AFTER FAILED INITIAL URETHROPLASTY

S. N. Wadhwa; R. Chahal; Ashok K. Hemal; N.P. Gupta; P.N. Dogra; Amlesh Seth

PURPOSE We evaluate the problems encountered during surgery and assess the results of different endoscopic and open surgical methods following failed urethroplasty for posttraumatic posterior urethral stricture. MATERIALS AND METHODS Since 1992 we have treated 23 patients in whom urethroplasty for posterior urethral strictures failed. Of these patients, 3 had undergone 2 previous repairs and 6 had additional complicating factors, such as fistula, periurethral cavity and false passage. End-to-end anastomosis was done in 14 patients via a transperineal (7) or transpubic (7) approach. In 1 patient substitution urethroplasty using a radial artery based forearm free flap was performed. In 3 patients a 2-stage urethroplasty was done, 4 underwent core-through optical internal urethrotomy and 1 underwent endoscopic marsupialization of a false passage. RESULTS At 1 to 5-year followup 3 of the 23 patients had restenoses (13%), including 2 in whom previous treatment failed. The remaining 87% of the patients void well and are continent, and there is no worsening of the preexisting potency status. CONCLUSIONS Previous failed urethral stricture repair complicates management due to fibrosis, impaired vascularity and limited urethra available for mobilization. Recurrent strictures less than 1.5 cm. can be managed successfully with core-through internal urethrotomy. End-to-end anastomosis is possible in the majority with generous use of inferior pubectomy or the transpubic approach with certain modifications. When residual inflammation or long strictures are present a 2-stage procedure is a safer option. Overall, reoperation can offer a successful outcome for the majority of these complex strictures.


Urologia Internationalis | 2001

Primary Squamous Cell Carcinoma of the Prostate: A Rare Clinicopathological Entity

G. Nabi; M.S. Ansari; Iqbal Singh; M.C. Sharma; P.N. Dogra

Primary squamous cell carcinoma of the prostate is an uncommon clinicopathological entity. It differs from more common adenocarcinomas in its cell of origin, biological behavior, therapeutic response to the usual hormonal manipulation and prognosis. The review shows that squamous cell carcinoma is biologically more aggressive than adenocarcinoma. Despite the agreement on its uniqueness, a controversy exists on the exact histopathogenesis, diagnostic criteria and modality of treatment. We report on 2 patients with primary squamous cell carcinoma of the prostate. One patient presented with lower urinary tract symptoms with a hard nodular prostate on digital rectal examination, and the other with acute urinary retention on normal digital rectal examination. The evaluation revealed metastasis in the pelvic and right femur in both cases. Palliative transurethral resection of the prostate with chemotherapy (Adriamycin based) was given in both the cases. However, both the patients died at 4 and 5 months of follow-up, respectively.


The Journal of Urology | 2006

Reconstructive Surgery for the Management of Genitourinary Tuberculosis: A Single Center Experience

Narmada P. Gupta; Rajeev Kumar; Om Prakash Mundada; Monish Aron; Ashok K. Hemal; P.N. Dogra; Amlesh Seth

PURPOSE We evaluated the role of surgery for genitourinary tuberculosis with special emphasis on reconstructive procedures. MATERIALS AND METHODS Case records of 241 patients with genitourinary tuberculosis who underwent surgery at our center during a period of 17 years were reviewed. Clinical features, organ involvement, investigations, treatment and outcome of therapy were studied. RESULTS There were 129 males and 112 females with a mean age of 34.6 years. The most common presentation was irritative voiding symptoms. Azotemia was seen in 54 (22.4%) cases. The most commonly involved organ was the kidney in 130 (53.94%) cases. Preoperative bacteriologic diagnosis was confirmed in 70 (29%) cases. All patients received antitubercular drug therapy for 9 months. A total of 248 procedures, including 33 endoscopic, 87 ablative and 128 reconstructive, were performed with some patients requiring more than 1 procedure. Early complications, which mainly involved the bowel, were seen in 19 (7.88%) cases. Bacteriologic cure was achieved in all culture positive cases. Renal functional parameters stabilized or improved in 44 of 54 patients (81.5%) in whom they were deranged at presentation. CONCLUSIONS Genitourinary tuberculosis is common in developing countries. Diagnosis is often delayed because of late presentation and many patients present with cicatrization sequelae. A combination of antitubercular drug therapy and judicious surgery achieves satisfactory results in the majority of cases. With improved antitubercular drug therapy and experience with the use of bowel segments in the urinary tract, more reconstructive procedures are being performed with satisfactory outcomes. In patients who undergo reconstructive procedures, a rigorous and prolonged followup is necessary.


The Journal of Urology | 1999

Core through urethrotomy with the Neodymium:YAG laser for posttraumatic obliterative strictures of the bulbomembranous urethra

P.N. Dogra; Monish Aron; T.P. Rajeev

PURPOSE We studied the safety and efficacy of core through urethrotomy with the neodymium (Nd):YAG laser for posttraumatic obliterative strictures of the bulbomembranous urethra. MATERIALS AND METHODS Eight patients a mean of 27.5 years old with posttraumatic (motor vehicle accidents) obliterative strictures of the bulbomembranous urethra were treated from May to December 1997. Laser treatment selection criteria were stricture length 2.0 cm. or less, good alignment between the urethral ends and no history of rectal injury or erectile dysfunction. All patients underwent core through urethrotomy with the Nd:YAG contact laser delivered with the 600 micro bare fiber at 15 to 25 W. The urethrotomy was guided only by a metal sound introduced through the suprapubic tract. RESULTS Blood loss was negligible and excellent visualization was maintained throughout the procedure. Operating time ranged from 45 to 70 minutes. There were no perioperative complications. Hospital stay was 24 hours in the first case and 6 to 8 hours in subsequent cases. All patients returned to work within 5 days. Urethroscopy was performed 4 and 12 weeks after catheter removal in all patients. Only 1 patient required repeat internal urethrotomy. Voiding cystourethrography revealed a stricture-free urethra in 7 cases. At last followup 7 to 14 months (mean 10.25) after the procedure mean maximum flow rate was 18.6 ml. per second (range 16.5 to 22.4) in the patients who were stricture-free and 11.8 ml. per second in 1 with recurrent stricture. CONCLUSIONS Core through urethrotomy with the contact Nd:YAG laser seems to be a safe and effective treatment option for select strictures. The hospital stay is remarkably short and complications are negligible. Re-stricture rates are likely to be low but more experience and longer follow-up are needed.

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Amlesh Seth

All India Institute of Medical Sciences

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Ashok K. Hemal

Wake Forest Baptist Medical Center

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N.P. Gupta

All India Institute of Medical Sciences

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M.S. Ansari

All India Institute of Medical Sciences

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Monish Aron

University of Southern California

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Narmada P. Gupta

All India Institute of Medical Sciences

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Rajeev Kumar

All India Institute of Medical Sciences

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G. Nabi

All India Institute of Medical Sciences

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Anurag Khaitan

All India Institute of Medical Sciences

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Ashish Kumar Saini

All India Institute of Medical Sciences

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