Comparison of Dimensional Accuracy between Open-Tray and Closed-Tray Implant Impression Technique in 15° Angled Implants.

STATEMENT OF PROBLEM: Various impression techniques have different effects on the accuracy of final cast dimensions. Meanwhile; there are some controversies about the best technique. PURPOSE: This study was performed to compare two kinds of implant impression methods (open tray and closed tray) on 15 degree angled implants. MATERIALS AND METHOD: In this experimental study, a steel model with 8 cm in diameter and 3 cm in height were produced with 3 holes devised inside to stabilize 3 implants. The central implant was straight and the other two implants were 15° angled. The two angled implants had 5 cm distance from each other and 3.5 cm from the central implant. Dental stone, high strength (type IV) was used for the main casts. Impression trays were filled with poly ether, and then the two impression techniques (open tray and closed tray) were compared. To evaluate positions of the implants, each cast was analyzed by CMM device in 3 dimensions (x,y,z). Differences in the measurements obtained from final casts and laboratory model were analyzed using t-Test. RESULTS: The obtained results indicated that closed tray impression technique was significantly different in dimensional accuracy when compared with open tray method. Dimensional changes were 129 ± 37µ and 143.5 ± 43.67µ in closed tray and open tray, while coefficient of variation in closed- tray and open tray were reported to be 27.2% and 30.4%, respectively. CONCLUSION: Closed impression technique had less dimensional changes in comparison with open tray method, so this study suggests that closed tray impression technique is more accurate.

Renal insufficiency is an independent risk factor for complications after partial nephrectomy.

PURPOSE: We identify and describe the postoperative outcomes of a single surgeon partial nephrectomy cohort. We performed univariate and multivariate analysis on preoperative patient characteristics, and their association with increased length of stay and postoperative complication rates. MATERIALS AND METHODS: Perioperative characteristics of 146 consecutive patients undergoing partial nephrectomy were recorded. Postoperative complications were defined as those occurring within 30 days using the Clavien postoperative complication scale. We conducted logistic regression analysis to evaluate the development of complications and linear regression analysis to determine the effect on length of stay. RESULTS: In a linear regression model patients with renal insufficiency had a mean of 1.7 +/- 0.6 days longer length of stay compared to those with normal renal function (p = 0.006). Complications occurred in 48.5% in the renal insufficiency group compared with 16.8% in the other cohort (p = 0.0004). There were no mortalities. On univariable analysis 4 factors were significantly associated with the development of complications including race (p = 0.03), preoperative Modification of Diet in Renal Disease less than 60 (p <0.0001), tumor size greater than 4 cm (p = 0.03) and estimated blood loss (p = 0.04). On multivariable analysis the 2 factors of Modification of Diet in Renal Disease less than 60 (p = 0.003) and race (p = 0.03) remained significant. The odds ratio for complications comparing patients with renal insufficiency to the normal cohort, adjusting for confounding factors, was 4.58 (95% CI 1.65-12.65). CONCLUSIONS: Preoperative renal insufficiency defined as Modification of Diet in Renal Disease less than 60 and non African-American race, which may be related to Modification of Diet in Renal Disease, are predictive of complications after partial nephrectomy. Decreased Modification of Diet in Renal Disease is an independent risk factor for increased length of hospital stay and increased complication rate in partial nephrectomy.

Polymorphism of the insulin gene is associated with increased prostate cancer risk.

High insulin levels are linked with increased cancer risk, including prostate cancer. We examined the associations between prostate cancer with polymorphisms of the insulin gene (INS) and its neighbouring genes, tyrosine-hydroxylase and IGF-II (TH and IGF2). In this study, 126 case-control pairs matched on age, race, and countries of origin were genotyped for +1127 INS-PstI in INS, -4217 TH-PstI in TH, and +3580 IGF2-MspI in IGF2. The homozygous CC genotype of +1127 INS-PstI occurred in over 60% of the population. It was associated with an increased risk of prostate cancer in nondiabetic Blacks and Caucasians (OR=3.14, P=0.008). The CC genotype was also associated with a low Gleason score <7 (OR=2.60, P=0.022) and a late age of diagnosis (OR=2.10, P=0.046). Markers in the neighbouring genes of INS showed only null to modest associations with prostate cancer. The polymorphism of INS may play a role in the aetiology of prostate cancer. Given the high prevalence of the CC genotype and its association with late age of onset of low-grade tumours, this polymorphism may contribute to the unique characteristics of prostate cancer, namely a high prevalence of indolent cancers and the dramatic increase in incidence with age.

Open surgical partial nephrectomy.

The goals of conservative resection of renal cell carcinoma are complete local surgical removal of the malignancy and preservation of adequate renal function. This is a delicate balance, which makes renal preserving surgery at times both challenging and controversial. Surgical management of renal cell carcinoma remains the most effective curative management. The increased use of cross-sectional imaging has led to an increased detection of incidental renal cell carcinomas at an earlier stage. The indications of nephron-sparing surgery (NSS) have evolved in the past decade. Clinically, there are scenarios where nephron-sparing surgery is absolutely indicated. However, in the setting of a normal contralateral kidney, radical nephrectomy is still considered by many to be the treatment of choice for localized renal cell carcinoma. There is now growing evidence that in the correct patient, the use of NSS in the above-mentioned situation is justified. Very recent data indicate that NSS provides effective and equivalent oncologic treatment for most renal cell carcinomas especially those 4 cm or smaller. Refined surgical techniques and new studies regarding the earlier diagnosis and biology of renal cell carcinoma, true incidence of occult multifocality, and comparable morbidity with radical nephrectomy make NSS an attractive tool in the armamentarium of the urologic surgeon.

Nephron-sparing surgery.

The curative management of renal cell carcinoma remains surgical. Recent advances in imaging and increased use of cross-sectional imaging modalities have led to an increased detection of incidental renal cell carcinomas. There is little debate regarding the role of nephron-sparing surgery (NSS) when absolutely indicated. Radical nephrectomy is still considered by many as the treatment of choice for localized renal cell carcinoma in the setting of a normal contralateral kidney. However, there is growing evidence that in the correct patient, the use of NSS in this setting is justified. Therefore, the indications of NSS have evolved in the past decade. Recent data indicate that radical nephrectomy and NSS provide effective and equivalent curative treatment for most renal cell carcinomas, especially those 4 cm or smaller. These data, along with new, refined surgical techniques, new studies regarding the biology of renal cell carcinoma and true incidence of occult multifocality, and earlier diagnosis make NSS an attractive consideration for the practicing urologist.

Renal cell carcinoma metastatic to the pancreas: clinical and radiological features.

OBJECTIVE: To review the clinical features, computed tomographic (CT) appearance, and treatment outcomes in a case series of patients with renal cell carcinoma (RCC) metastatic to the pancreas. PATIENTS AND METHODS: We retrospectively reviewed the records of 23 patients (15 men and 8 women) with RCC metastatic to the pancreas, detected by CT examination between 1986 and 1996. All patients had undergone a previous nephrectomy for RCC. RESULTS: Isolated mild elevation in liver function test results (in 5 patients) or in serum amylase level (in 8 patients) was observed. New-onset diabetes was detected in 3 patients. The CT characteristics of the pancreatic metastases generally resembled those of primary RCC with well-defined margins and greater enhancement than normal pancreas with a central area of low attenuation. The mean interval between resection of the primary RCC and detection of the pancreatic metastases was 116 months (range, 1-295 months). In 18 patients (78%), the pancreatic metastases were diagnosed more than 5 years after nephrectomy. The pancreas was the initial metastatic site in 12 patients (52%). Survival was shortened with higher tumor grade (mean survival time of 41 months and 10 months in patients with grade 2 and 3, respectively). Surgical resection was carried out in 11 patients (7 distal and 3 total pancreatectomies and 1 distal pancreatectomy followed 4 years later by total pancreatectomy), with 8 patients alive at a mean follow-up of 4 years, 6 of whom remained free of recurrence. Overall, 12 patients (52%) were alive at a mean of 42 months after diagnosis of metastatic disease. CONCLUSIONS: The appearance of metastatic RCC lesions in the pancreas closely resembles the appearance of primary RCC on CT images. Pancreatic metastases from RCC are frequently detected many years after nephrectomy. Patient survival correlates with tumor grade. Histologic analysis of pancreatic masses in patients with a history of resected primary RCC is important since the prognosis for RCC metastatic to the pancreas is much better than that for primary pancreatic adenocarcinoma.

Technique for nerve dissection.

Nerve-sparing radical retropubic prostatectomy is a reasonable treatment option in localized prostate cancer with minimal morbidity. Recent techniques in neurovascular bundle preservation could lead to an overall improvement in postoperative quality of life without compromising cancer control in the appropriately selected patient. Different techniques for neurovascular bundle preservation have been described by most major centers. This brief article describes the updated technique of nerve-sparing radical retropubic prostatectomy for clinically localized prostate cancer. Our technique of nerve dissection starts at the lateral aspect of the prostate with secondary urethral dissection. We believe this technique is easy to learn and decreases dissection around the striated sphincter.

Comparison of clinically nonpalpable prostate-specific antigen-detected (cT1c) versus palpable (cT2) prostate cancers in patients undergoing radical retropubic prostatectomy.

OBJECTIVES: Serum prostate-specific antigen (PSA) testing has led to increased detection of clinically localized prostate cancer. We analyzed the clinical characteristics and outcome of digitally palpable (cT2) and PSA detected (cT1c) prostate cancers. METHODS: We evaluated 4453 patients with clinically localized prostate cancer who underwent radical retropubic prostatectomy (RRP) between 1987 and 1995 at the Mayo Clinic. Overall, 1041 (23.4%), 1076 (24.2%), and 2336 (52.5%) patients had cT1c, cT2a, and cT2b/c disease, respectively. Patients were analyzed with regard to Gleason score, preoperative PSA, pathologic stage, deoxyribonucleic acid (DNA) ploidy, margin status, tumor volume, and adjuvant treatment. Survival outcomes at 5 and 7 years were estimated using the Kaplan-Meier method with respect to the end points of systemic/local clinical progression and clinical and/or PSA progression (greater than 0.2 microg/mL). Multivariate analysis was employed to estimate the relative risk of progression associated with each clinical stage when adjusted for the above factors. RESULTS: Clinical T1c tumors were more likely to be organ confined (76% versus 54%), have a Gleason score less than 7 (75% versus 61%), and be diploid (80% versus 70%) than cT2b/c tumors (P <0.001). Clinical T1c disease closely resembled cT2b/c disease with respect to preoperative PSA. Considering pathologic stage, DNA ploidy, and tumor volume, cT1c tumors were comparable to cT2a lesions. Of the patients with T1c cancers, 96.2% had clinically significant cancer on the basis of pathologic grade and tumor volume. The 5 (and 7 year) systemic/local clinical progression-free and PSA progression-free survivals for cT1c tumors were 97.7+/-0.7% (96.4+/-1.1%) and 82.2+/-1.7% (72.9+/-3.8%), respectively. There was a significant survival advantage at 5 and 7 years regarding both end points for cT1c and cT2a compared with cT2b/c tumors (P <0.001). Multivariate analysis revealed a continued benefit in PSA and systemic/local clinical progression for cT1c tumors compared with cT2b/c tumors adjusting for the above factors. CONCLUSIONS: Clinical T1c tumors are clinically significant cancers. When compared with digitally palpable tumors, progression-free survival rates for cT1c tumors are similar to cT2a lesions, but are significantly better than cT2b/c lesions. This supports continued use of serum PSA to detect potentially curable prostate cancer.

Radical retropubic prostatectomy plus orchiectomy versus orchiectomy alone for pTxN+ prostate cancer: a matched comparison.

PURPOSE: Untreated stage pTxN+ prostate cancer is associated with a poor outcome. Monotherapy (surgery, radiation, hormonal therapy) alone is associated with a high progression rate. We evaluate whether radical prostatectomy and pelvic lymphadenectomy plus early adjuvant orchiectomy impart a survival advantage compared to pelvic lymphadenectomy and orchiectomy alone in a matched cohort of patients. MATERIALS AND METHODS: Between 1966 and 1995, 382 and 79 patients with stage pTxN+ prostate cancer underwent pelvic lymphadenectomy and radical prostatectomy plus early adjuvant orchiectomy (within 3 months of prostatectomy), and pelvic lymphadenectomy and orchiectomy only, respectively. We selected 79 matched controls from the prostatectomy plus orchiectomy group for the orchiectomy group. Patients were matched according to the number of positive nodes, clinical grade, clinical stage, age, year of surgery and preoperative prostate specific antigen (after 1987). The Kaplan-Meier method and stratified Cox proportional hazards model were used to estimate overall and cause specific survival for the 2 groups. RESULTS: There was an overall survival advantage at 10 years for the prostatectomy plus orchiectomy (66+/-6%) compared to the orchiectomy (28+/-6%) group (p <0.001, risk ratio 0.36, 95% confidence interval 0.20 to 0.66). There was also an advantage in cause specific survival at 10 years in the prostatectomy plus orchiectomy (79+/-5%) versus the orchiectomy (39+/-7%) group (p <0.001, relative risk 0.28, 95% confidence interval 0.13 to 0.59). After 1987, when matched on preoperative prostate specific antigen, the apparent survival advantage at 5 years with radical prostatectomy was smaller (79+/-8 versus 63+/-9% orchiectomy) and not significant (p = 0.19). CONCLUSIONS: This retrospective study of patients with stage pTxN+ PC suggests that radical prostatectomy with early adjuvant orchiectomy may provide a significant advantage in overall and cause specific survival compared to orchiectomy alone.

The urological manifestations of hollow visceral myopathy in children.

PURPOSE: Hollow visceral myopathy is a rare clinical entity characterized by impaired intestinal function in the absence of mechanical occlusion. It can affect the smooth muscle of the whole or segments of the gastrointestinal tract and occasionally the urinary tract. We examined the urological manifestations of hollow visceral myopathy and management in the pediatric population. MATERIALS AND METHODS: We reviewed the records of 14 male patients 1 day to 2 years old (mean age 4.6 months) and 10 female patients 1 day to 5 years old (mean age 9.4 months) at presentation to our institution with hollow visceral myopathy. In all patients genitourinary tract ultrasound, voiding cystourethrography and serum creatinine measurement were done at presentation. RESULTS: All patients had gastrointestinal obstructive symptoms at presentation and 11 (46%) had urological symptoms, including urinary retention in 2, urinary tract infection in 3, and a prenatal diagnosis of megacystis and hydroureteronephrosis in 6. Overall 22 patients (92%) had urological abnormalities, all had poor bladder emptying and recurrent urinary tract infections, and 13 had megacystis associated with bilateral hydroureteronephrosis in 9 and unilateral hydroureteronephrosis in 2. There were 9 deaths from extensive gastrointestinal involvement and sepsis. Of the surviving 15 patients 13 have urological abnormalities, including 8 who perform and tolerate clean intermittent catheterization via the urethra and are well. Of the 4 male infants who did not tolerate clean intermittent catheterization appendicovesicostomy was done in 1, a Casale tube was placed in 1 and vesicostomy was performed in 2. The remaining female patient has day and night wetting. CONCLUSIONS: Urological abnormalities are common in hollow visceral myopathy and they can contribute to presenting symptoms. Clean intermittent catheterization via the urethra to aid in bladder emptying and decrease the frequency of urinary tract infections is the mainstay of treatment but surgery to construct an alternative catheterizable channel or vesicostomy may be required in intolerant patients.

Post-transplant lymphoceles: a critical look into the risk factors, pathophysiology and management.

To define better the prevalence and pathophysiology of lymphoceles following renal transplantation, we prospectively evaluated 118 consecutive renal transplants performed in 115 patients (96 cadaveric, 22 living-related, 7 secondary and 111 primary). Ultrasonography was performed post-operatively and during rehospitalizations or whenever complications occurred. Perirenal fluid collections were identified in 43 patients (36%). Lymphoceles with a diameter of 5 cm. or greater were identified in 26 of 118 cases (22%). Eight patients (6.8%) had symptomatic lymphoceles requiring therapy. The interval for development of symptomatic lymphoceles was 1 week to 3.7 years (median 10 months). Risk factors for the development of lymphoceles were examined by univariate and multivariate analysis, and included patient age, sex, source of transplants (cadaver versus living-related donor), retransplantation, tissue match (HLA-B/DR), type of preservation, arterial anastomosis, occurrence of acute tubular necrosis-delayed graft function, occurrence of rejection, and use of high dose corticosteroids. Univariate analysis showed a significant risk for the development of lymphoceles in transplants with acute tubular necrosis-delayed graft function (odds ratio 4.5, p = 0.004), rejection (odds ratio 25.1 p < 0.001) and high dose steroids (odds ratio 16.4, p < 0.001). When applying multivariate analyses using stepwise logistic regression, only rejection was associated with a significant risk for lymphoceles (symptomatic lymphoceles--odds ratio 25.08, p = 0.0003, all lymphoceles--odds ratio 75.24, p < 0.0001). When adjusting for rejection, no other risk factor came close to being significant (least p = 0.4). Therapy included laparoscopic peritoneal marsupialization and drainage in 1 patient, incisional peritoneal drainage in 4 and percutaneous external drainage in 3 (infected). All symptomatic lymphoceles were successfully treated without sequelae to grafts or patients. We conclude that allograft rejection is the most significant factor contributing to the development of lymphoceles. Therapy of symptomatic lymphoceles should be individualized according to the presence or absence of infection.