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This case report describes the novel use of ultrasound-guided MRI-fusion biopsy to sample an extraluminal perirectal mass. This is a 64-year-old man with a history of pT3N2b mucinous adenocarcinoma of the right colon with metastatic disease to the mesocolic lymph nodes. Two years after initial resection he was found on restaging CT to have a mass measuring ∼4.0 × 4.8 cm superior to the seminal vesicles. Fluorodeoxyglucose (FDG)-positron emission tomography (PET) showed a moderately FDG avid soft tissue mass interposed between the prostate and the rectum. Multiparametric MRI revealed a 6.2 × 4.6 × 2.8 cm heterogeneous lobulated T2 hyperintense mass with enhancement just superior to the seminal vesicles. This mass was unable to be viewed using sigmoidoscopy. Using UroNAV technology, we were able to biopsy the mass in the clinic setting. Biopsy was confirmed as recurrent mucinous adenocarcinoma.

CONTEXT: Local recurrence after radiotherapy for prostate cancer remains challenging to treat effectively. Although oncologic control is highest with salvage prostatectomy, the procedure is associated with substantial morbidity. OBJECTIVE: To identify factors associated with successful salvage cryoablation for radiorecurrent prostate cancer. DESIGN: We retrospectively reviewed the medical records of patients who underwent salvage cryoablation at our institution between 2005 and 2015. All patients had biopsy-proven local recurrence after radiotherapy. Patients with seminal vesicle invasion or metastases were excluded. Complete follow-up was obtained for all patients. MAIN OUTCOME MEASURES: Primary study endpoint was biochemical progression-free survival based on the Phoenix criteria. RESULTS: Seventy-five patients underwent salvage cryotherapy. Mean patient age was 69.3 years. The overall biochemical salvage rate was 50.7% at a median follow-up of 3.9 years. The following factors were independently associated with successful cryotherapy: Precryotherapy Gleason score of 3 + 3 or 3 + 4, low precryotherapy prostate-specific antigen (PSA), low precryotherapy PSA density, longer time to PSA nadir after radiotherapy, and low postcryotherapy PSA nadir. A postcryotherapy PSA nadir of 0.5 ng/mL or less was associated with a biochemical progression-free survival of 79.7% at 3 years and 64.7% at 5 years, whereas a postcryotherapy PSA nadir above 0.5 was associated with a biochemical progression-free survival of 5.6% at 3 years and 0% at 5 years (p < 0.0001). CONCLUSION: Approximately 50% of the patients achieved biochemical salvage with cryoablation at 5 years. Nadir PSA after salvage was the strongest predictor of biochemical progression-free survival in our cohort.

INTRODUCTION AND OBJECTIVES:DNA promoter hypermethylation (Confirm MDX) may pick up occult prostate cancer due to a field defect the tumor exerts on normal tissue. The reported negative predictive ...

INTRODUCTION: Radical prostatectomy (RP) with pelvic lymph node dissection (PLND) is the standard treatment of high-risk prostate cancer. High-risk patients and those with lymph node metastasis (LNM) require further treatment. We review outcomes of RP+PLND in Kaiser Permanente Southern California (KPSC). METHODS: Patients who underwent RP+PLND in KPSC from January 1, 2001, to July 1, 2015 were included. Patient charts were retrospectively reviewed for demographic information and clinicopathologic data which were used to calculate positive surgical margin rate, LNM, adjuvant treatment, 5-year biochemical recurrence, and overall survival. Univariate and multivariate logistic regression analyses were used to identify factors associated with margin positivity. RESULTS: Patients (N = 1829) underwent RP+PLND (241 high-risk, 943 intermediate-risk, 645 low-risk). Positive margin rates were 17.8%, 14.8%, and 11.9% in the high, intermediate- and low-risk groups. Biochemical recurrence rates were 22% in high-risk and 12.1% in the low-risk category. Androgen deprivation use was 4.1% in the high-risk group and 0.9% in the low-risk group. Five-year overall survival was 92.5% in lymph node-positive patients and 94.9% in lymph node-negative patients (p = 0.8). On multivariate analysis, age (odds ratio [OR] = 1.02, p = 0.02), prebiopsy prostate-specific antigen (OR = 1.02, p < 0.001), and clinical T stage (OR = 1.49, p = 0.01) were associated with margin positivity. CONCLUSION: In KPSC, RP+PLND was performed in patients with low-, intermediate-, and high-risk prostate cancer. Age, prebiopsy prostate-specific antigen, and clinical stage were associated with positive surgical margins in patients with LNM. Recipients of RP+PLND with LNM and positive surgical margins required adjuvant treatment.

Tumors of the anterior prostate (ie, the portion of the prostate anterior to the urethra) account for approximately 20% of all prostate cancers. Although anterior prostate cancers frequently occur, they have historically been underdetected because of infrequent sampling. Recent advances in multiparametric magnetic resonance imaging and improved biopsy schemes have significantly increased our diagnostic accuracy for detecting anterior tumors. Herein, we review these developments and highlight key aspects of the diagnosis and management of anterior prostate cancers.

Background: Urachal remnants are a group of rare anatomical anomalies that include cysts, diverticula, and tumors. We present a case of a young female patient with dyspareunia and dysorgasmia related to a urachal cyst. Case: A patient with unique presentation of urachal cyst treated robotically. Patient had complete resolution of symptoms postoperatively. Conclusion: Robot-assisted excision of the urachal remnant provided durable symptom relief.

Objective To determine whether multiparametric magnetic resonance imaging might improve the identification of patients with higher risk disease at diagnosis and thereby reduce the incidence of undergrading or understaging. Methods We retrospectively reviewed the clinical records of 115 patients who underwent multiparametric magnetic resonance imaging before radical prostatectomy. We used Epstein's criteria of insignificant disease with and without a magnetic resonance imaging (MRI) parameter (apparent diffusion coefficient) to calculate sensitivity, specificity, as well as negative and positive predictive values [NPV and PPV] across varying definitions of clinically significant cancer based on Gleason grade and tumor volume (0.2 mL, 0.5 mL, and 1.3 mL) on whole-mount prostate specimens. Logistic regression analysis was performed to determine the incremental benefit of MRI in delineating significant cancer. Results The majority had a prostate-specific antigen from 4.1-10.0 (67%), normal rectal examinations (90%), biopsy Gleason score ≤6 (68%), and ≤2 cores positive (55%). Of the 58 patients pathologically staged with Gleason 7 or pT3 disease at prostatectomy, Epstein's criteria alone missed 12 patients (sensitivity of 79% and NPV of 68%). Addition of apparent diffusion coefficient improved the sensitivity and NPV for predicting significant disease at prostatectomy to 93% and 84%, respectively. MRI improved detection of large Gleason 6 (≥1.3 mL, P = .006) or Gleason ≥7 lesions of any size (P Conclusion Integration of MRI with existing clinical staging criteria helps identify patients with significant cancer. Clinicians should consider utilizing MRI in the decision-making process.

Objectives: Since its introduction, there have been many refinements in the technique and implementation of robotic-assisted radical prostatectomy (RARP). However, it is unclear whether operative outcomes are influenced by surgical case order. We evaluated the effect of case order on perioperative outcomes for RARP within a large health maintenance organization. Materials and Methods: We conducted a retrospective review of RARP cases performed at our institution from September 2008 to December 2010 using a single robotic platform. Case order was determined from surgical schedules each day and surgeries were grouped into 1 st , 2 nd and 3 rd round cases. Fourth round cases (n = 1) were excluded from analysis. We compared clinicopathological variables including operative time, estimated blood loss (EBL), surgical margin rates and complication rates between groups. Results: Of the 1018 RARP cases in this cohort, 476 (47%) were performed as 1 st round cases, 398 (39%) 2 nd round cases and 144 (14%) 3 rd round cases by a total of 18 surgeons. Mean operative time was shorter as cases were performed later in the day (213 min vs. 209 min vs. 180 min, P < 0.0001) and similarly, EBL also decreased with surgical order (136 mL vs. 134 mL vs. 103 mL, P = 0.01). Transfusion rates, surgical margin rates and complication rates did not significantly differ between groups. Patients undergoing RARP later in the day were much more likely to have a hospital stay of 2 or more days than earlier cases (10% vs. 11% vs. 32%, P = 0.01). Conclusions: Surgical case order may influence perioperative outcomes for RARP with decreased operative times and increased length of hospital stay associated with later cases. These findings indicate that select perioperative factors may improve with ascending case order as the surgical team "warms up" during the day. In addition, 3 rd round cases can increase hospital costs associated with increased lengths of hospital stay. Knowledge of these differences may assist in surgical planning to improve outcomes and limit costs.

OBJECTIVE Patients with sarcomatoid renal cell carcinoma (sRCC) are known to have poor prognosis and response to systemic therapy. We set out to examine the influence of pathological tumour characteristics on survival to aid prognostication and clinical trial design. PATIENTS AND METHODS A single-centre database was reviewed to identify all patients with sRCC. Clinical variables and pathological information, including histology, necrosis, percentage of sarcomatoid features (PSF) and microvascular invasion (MVI), were recorded and correlated to outcome. RESULTS Analyses of 104 patients with sRCC found that the median (range) size of tumours was 9.5 cm (2.5–30), 65% of patients had areas of clear cell histology, and 69.2% had metastatic disease at presentation. The PSF did not influence tumour size, stage, necrosis, MVI, nodes or metastasis. A total of 85 patients (81.7%) died during the follow-up period with a median (95% confidence interval [CI]) survival of 5.9 months (4.7–8.9). In the overall cohort, Eastern Cooperative Group performance status (ECOGPS), tumour size and metastatic disease were independent predictors of poor survival. MVI, PSF and percentage necrosis were strongly associated with outcome but were not independent predictors of outcome. A multivariate risk model was established that incorporated six covariates (tumour size, MVI, ECOGPS, PSF, necrosis, and metastatic disease) to produce a predictive tool. CONCLUSIONS Both patients with localized and metastatic sRCC have very poor survival outcomes. Pathological features MVI, PSF and necrosis are important predictors of survival and could be used in a prognostic model while grade and histology do not influence prognosis. A prognostic model, if validated, could aid in patient counselling and/or clinical trial design. Keywords: sarcomatoid, kidney cancer, adjuvant, prognosis, RCC INTRODUCTION Every year ≈ 13,000 men and women die from kidney cancer in the United States [1]. Extensive research has advanced the understanding of RCC from the classic term ‘hypernephroma’ to half a dozen distinct subtypes that have had the mechanisms of malignant transformation characterized. One entity, sarcomatoid RCC (sRCC), is poorly understood and updated classification schemes no longer consider it a distinct subtype [2,3]. These tumours generally coexist with a variable amount of carcinoma (any subtypes) and are generally believed to represent a common pathway of de-differentiation of renal tumours [4]. While only 5% of patients with RCC have sarcomatoid features, these tumours account for 15–20% of patients with advanced disease [5,6]. Improved understanding of the biology of RCC has led to the introduction of six new systemic therapies since 2005. However, agents such as sunitinib, sorafenib and temsirolimus appear to have only limited efficacy in treating patients with sRCC [7–9]. Recently, several clinical trials have specifically targeted patients with sRCC, some of which have stratified patients based on histological features, including clear-cell vs non-clear-cell histology, and by the percentage of sarcomatoid features (PSF) in the primary tumour. Stratification in such trials could help to assess therapeutic response if the histology and the PSF influences the disease biology [10]. However, currently the role of these pathological characteristics in determining biology and outcome is unclear. Clinicians recognize that sarcomatoid tumours are associated with poor outcome, but there are a subset of patients who have exhibited extended survival. Only a limited number of studies have attempted to correlate pathological features with prognosis [5,11]. To better counsel patients with sRCC and to risk-stratify those involved in future clinical trials, we set out to determine the importance of pathological characteristics in patients in a large single-centre cohort of consecutive patients diagnosed with sRCC.

The introduction of serum prostate-specific antigen to the prostate cancer screening algorithm has led to an increase in prostate cancer diagnosis as well as a migration toward lower-stage cancer at the time of diagnosis. This stage migration has coincided with changes in treatment options; these include active surveillance, new therapies, and advances in surgical techniques. Use of robot-assisted radical prostatectomy (RARP) as a surgical technique has seen a significant increase over the past several years: the number of patients undergoing RARP has risen from 1% to 40% of all prostatectomies from 2001-2006 to as many as 80% in 2010. The robotic interface provides a 3D magnified view of the surgical field, intuitive instrument manipulation, motion scaling, tremor filtration, and excellent dexterity and range of motion. However, in some cases, the lack of tactile (haptic) feedback may limit the surgeon's decision making ability in assessing malignant involvement of the neurovascular bundles. Pre-operative planning relies on nomograms based on limited clinical and prostate biopsy information. The surgical decision to spare or resect the neurovascular bundles is based on clinical information which is not spatially or anatomically based. Advances in magnetic resonance imaging (MRI) may provide spatially localized information to fill this void and aid surgical planning, particularly for robotic surgeons. In this review, we discuss the potential role of pre-operative MRI in surgical planning for radical prostatectomy.

Controlled tissue cooling, or hypothermia, has been used therapeutically for decades to mitigate the negative effects of traumatic, ischemic, and surgical insults. When applied systemically, moderate hypothermia can attenuate or prevent the extent of neurologic sequelae. Localized hypothermia, on the other hand, has the capacity to reduce tissue edema, suppress inflammation, and minimize the severity of peripheral nerve injury. Therapeutic hypothermia has been used in critical care, neurosurgery, ophthalmology, otolaryngology, cardiothoracic surgery and most recently in urology. Nerve injury during radical pelvic surgery can result in urinary incontinence or retention, impotence and bowel dysfunction. Localized hypothermia during radical prostatectomy has demonstrated improved recovery of urinary continence and erectile function, and similar benefits might be observed in other types of radical pelvic surgery.

Epithelial cell transformation has been demonstrated in numerous animal models for the study of solid tumor biology. However, little evidence exists for human epithelial cell transformation without previous immortalization via genetic influences such as SV40 T-antigen, thus limiting our knowledge of the events that can transform naive human epithelium. Here we describe a system developed in our laboratory to directly transform freshly isolated primary human prostate epithelial cells without previous culture or immortalization. Prostate tissue is obtained from patients and benign tissue is separated from malignant tissue. Benign and malignant tissues are mechanically and enzymatically dissociated to single cells overnight, and immune cells and epithelial subsets are isolated on the basis of differential expression of surface antigens. Epithelial progenitor cells are transduced with lentiviruses expressing oncogenes and combined with inductive stroma for in vivo studies. At 8-16 weeks after transplantation into immune-deficient mice, the development of lesions, histologically classified as benign prostate, prostatic intraepithelial neoplasia and adenocarcinoma, can be evaluated.

In the past 15 years, there has been an increased understanding of the tumor biology of renal cell carcinoma (RCC). The identification of vascular endothelial growth factor (VEGF), its related receptor (VEGFR), and the mammalian target of rapamycin as dysregulated signaling pathways in the development and progression of RCC has resulted in the rational development of pharmaceutical agents capable of specifically targeting key steps in these pathways. Clinical trials have demonstrated survival benefit with these agents, particularly in clear cell RCC patients. However, metastatic RCC will progress in all patients, resulting in a critical need to determine patient risk and optimize treatment. The goal of this article is to highlight the significant breakthroughs made in understanding the critical genetic alterations and signaling pathways underlying the pathogenesis of RCC. The discovery of prognostic factors and development of comprehensive nomograms to stratify patient risk and predictive biomarkers to facilitate individualized treatment selection and predict patient response to therapy also are reviewed.

Study Type – Prognosis (retrospective cohort) Level of Evidence 2b What’s known on the subject? and What does the study add? Pathology reporting is an important aspect of cancer care for all solid malignancies and the College of American Pathologists has set forth specific guidelines. Many prognostic nomograms for kidney cancer rely on important pathologic characteristics but it is unknown if current reporting practices permit use of these models. This study shows limitations in the current pathological reporting practices for kidney cancer. Guidelines set forth by the College of American Pathologists are frequently not met and this could limit the use of prognostic models and enrollment into adjuvant trials. Efforts should be made to improve reporting practices by methods such as standard template reporting. OBJECTIVE • To evaluate whether current nephrectomy pathology reports are sufficient to allow clinicians to use prognostic nomograms, tailor surveillance, enroll patients into adjuvant trials and select systemic therapy for renal cell carcinoma (RCC). PATIENTS AND METHODS • Nephrectomy pathology reports were obtained from the LA County Tumor Registry. Key reporting elements identified by the College of American Pathology (CAP) and utilized in RCC prognostic models were abstracted. Hospital type was coded as community, teaching or cancer centre. • Reporting quality was assessed across hospital type and year. RESULTS • A total of 317 of 344 sampled reports (92.2%) met the inclusion criteria. Tumour size and margin status were commonly reported. Some 90.2% and 84.2% of reports provided data on histology and Fuhrman grade. Tumour classification was omitted in 27.8%. • Microvascular invasion and necrosis were infrequently reported (44.5% and 25.6%, respectively). Only 59.9% of reports met CAP guidelines for tumour classification, margin, size, histology and grade. • Two prognostic nomograms (Stage, Size, Grade and Necrosis system and Kattan) could rarely be utilized (15.8% and 12.3%, respectively), whereas the UCLA Integrated Staging System could be used frequently (65.6%). There were discrepancies satisfying CAP guidelines between community, teaching and cancer centre hospitals, with 54.7%, 70.5% and 75% of reports meeting CAP criteria (P= 0.0102). CONCLUSIONS • Current RCC pathology reporting fails to satisfy CAP guidelines, does not permit the use of prognostic systems, and may hinder enrollment into adjuvant trials and the selection of systemic therapy. Important reporting discrepancies exist between hospital types, with cancer centres performing best. • Quality improvement initiatives to encourage consistent, comprehensive and clinically relevant pathology reports would improve the quality of RCC patient care.

Robotic pelvic lymphadenectomy is a well established procedure in the urologic and gynecologic literature. To our knowledge robotic pelvic lymphadectomy for metastatic melanoma has yet to be described. Herein we present the first report of robot-assisted pelvic lymphadenectomy in malignant melanoma. After placement of six laparoscopic ports (12 mm camera, three 8-mm robotic ports, 12-mm and 5-mm assistant ports) the DaVinci S robot (Intuitive Surgical, CA, USA) was docked in standard fashion with the patient in low lithotomy. In both cases the patients had enlarged pelvic lymph nodes on computed tomography and complete excision of these masses was accomplished along with complete lymphadenectomy extending from Cooper’s ligament to just below the hypogastric artery in case 1 and to level of the bifurcation of aorta in case 2. A PK Maryland Dissector and monopolar scissors were used for dissection. Both patients were discharged on postoperative day #1. Robotic pelvic lymphadenectomy can be safely used for management of patients with metastatic melanoma involving the pelvic lymph nodes. Compared with the standard open procedure, pelvic lymphadenectomy with robotic assistance is associated with excellent vision and minimum morbidity.

After radical prostatectomy continence is commonly defined as no pads except a security pad or 0 to 1 pad. We evaluated the association of pad status and urinary quality of life to determine whether security and 1 pad status differ from pad-free status to better define 0 pads as the post-prostatectomy standard.A total of 500 consecutive men underwent robot assisted radical prostatectomy from October 2003 to July 2007. Data were collected prospectively and entered into an electronic database. Postoperatively men completed self-administered validated questionnaires including questions on 1) daily pad use (0, security, 1, or 2 or more), 2) urine leakage (daily, about once weekly, less than once weekly or not at all), 3) urinary control (none, frequent dribbling, occasional dribbling or total control), 4) American Urological Association symptom score and 5) urinary quality of life.Postoperatively men who indicated 0 pad use had a mean +/- SE symptom score of 5.8 +/- 0.3 and pleased quality of life (1.16 +/- 0.08). In contrast, men with a security pad and 1 pad had a symptom score of 7.6 +/- 0.7 and 9.2 +/- 0.6 but mixed quality of life (2.78 +/- 0.18 and 3.41 +/- 0.15, respectively, p0.0005).Results show a significant decrease in quality of life between no pads (1.16 or pleased), a security pad and 0 or 1 pad (2.78 and 3.41 or mixed, respectively). Findings do not support defining continence with a security pad or 0 to 1 pad. Continence should be strictly defined as 0 pads.

Cryotherapy is a technique to ablate tissue by local induction of extremely cold temperatures. Recently, the American Urological Association Best Practice Statement recognized cryoablation of the prostate as an established treatment option for men with newly diagnosed or radiorecurrent organ-confined prostate cancer. Emerging data suggest that, in select cases, cryoablation may have a role in focal ablation of prostate. The current state of the art of cryoablation in these applications is reviewed.

Adipose tissue has been suggested to contribute to the pathogenesis of various disease states, including prostate cancer. We investigated the association of cytokines and growth factors secreted by periprostatic adipose tissue with pathological features of aggressive prostate cancer.Periprostatic adipose tissue was harvested from patients undergoing radical prostatectomy and cultured for 24 hours to generate conditioned medium or snap frozen immediately for functional signaling profiling. Multiplex analysis of the periprostatic adipose tissue conditioned medium was used to detect cytokine levels and compared to patient matched serum from 7 patients. Interleukin-6 in serum and periprostatic adipose tissue conditioned medium was further analyzed by enzyme-linked immunosorbent assay and correlated with clinical variables, such as age, body mass index and Gleason score, in 45 patients. Interleukin-6 expression in periprostatic adipose tissue was determined by immunohistochemistry. Reverse phase protein microarray technology was used to analyze cell signaling networks in periprostatic adipose tissue.Interleukin-6 in periprostatic adipose tissue conditioned medium was approximately 375 times greater than that in patient matched serum and levels correlated with pathological grade. This finding was further extended by cell signaling analysis of periprostatic adipose tissue, which showed greater phosphorylation on Stat3 with high grade tumors (any component of Gleason score 4 or 5).Higher Gleason score correlated with high levels of conditioned medium derived interleukin-6. Moreover, cell signaling analysis of periprostatic adipose tissue identified activated signaling molecules, including STAT3, that correlated with Gleason score. Since STAT3 is interleukin-6 regulated, these findings suggest that periprostatic adipose tissue may have a role in modulating prostate cancer aggressiveness by serving as a source of interleukin-6. Also, we found low numbers of inflammatory cells in the fat, suggesting that adipocytes are the major secretors of interleukin-6.

To report the first application of preemptive local hypothermia during robotic-assisted laparoscopic prostatectomy (hRLP) to attenuate inflammation. Surgical excision of the prostate during radical prostatectomy causes inflammatory damage to the surrounding neuromuscular tissues that could affect urinary continence.Of 50 consecutive patients undergoing nerve-sparing hRLP (case numbers 668-717; 3 were excluded--2 underwent radiotherapy and 1 was withdrawn because of balloon failure), 47 were prospectively compared with a standard RLP cohort (case numbers 1-667). Pelvic cooling was achieved using cold irrigation and an endorectal cooling balloon cycled with 4 degrees C saline. The intracorporeal temperatures were measured. Continence was defined as 0 urinary pads. The Kaplan-Meier analysis of the time to 0 pads and multivariate Cox proportional hazards regression analysis was used to examine the group differences in continence after adjusting for the baseline characteristics.The median temperature was 29.0 degrees C (endorectal cooling balloon only, range 24.4 degrees-35.9 degrees C) and 25.5 degrees C (endorectal cooling balloon plus irrigation, range 19.4 degrees-34.0 degrees C). The time to 0-pad status was determined in 590 of 667 controls (88%). The 3-month hRLP 0-pad rate was 86.8% +/- 5.8% and was 68.6% +/- 2.0% for the controls. The return to continence was faster for hRLP vs controls: median 39 days (range 0-110) vs 59 days (range 1-720), respectively (P = .002, log-rank test). A multivariate analysis adjusting for factors, including age, American Urological Association symptom score, abbreviated International Index of Erectile Function-5, body mass index, prostate weight, stage, nerve-sparing, and learning curve demonstrated a faster return to continence for the hRLP group relative to the control group (hazard ratio 1.66, 95% confidence interval 1.11-2.49, P = .014).This study represents the initial application of local hypothermia to reduce the traumatic inflammatory sequela of RLP. Hypothermia was easily induced and safe and resulted in a statistically significant improvement in early postoperative continence.

To identify surgeon specific factors for preserving sexual function (and minimize patient related factors) we report 2-year potency outcomes in men 65 years or younger with normal preoperative sexual function undergoing nerve sparing robot assisted laparoscopic radical prostatectomy.Between July 2004 and February 2006, 200 consecutive patients underwent robot assisted laparoscopic radical prostatectomy by 1 surgeon. Inclusion criteria were age 65 years or younger with normal baseline 5-item International Index of Erectile Function score of 22 to 25 and complete 2-year followup. Postoperatively potency was defined by a yes to "erections adequate for vaginal penetration" and "satisfactory erections" on prospective self-administered validated questionnaires with or without phosphodiesterase type 5 medications. Men also reported 5-item International Index of Erectile Function scores and erectile fullness of 0% to 10%, 25%, 50%, 75% or 100% compared to before surgery.A total of 62 patients met the inclusion criteria, and of these 3 were lost to followup and 1 was excluded from study due to receiving hormonal therapy. At 3 months 32.1% reported potency. At 24 months potency was 89.7% (52 of 58) overall, 93.0% (40 of 43) for bilateral and 80.0% (12 of 15) for unilateral nerve sparing. For potent men the mean 5-item International Index of Erectile Function score was 20.4 at 3 months vs 21.3 at 24 months. Mean erectile firmness at 24 months was 91% compared to preoperative baseline, with 34 of 52 (65%) reporting 100% of preoperative fullness. The 5-item International Index of Erectile Function score and fullness at 24 months were equivalent for unilateral nerve sparing and bilateral nerve sparing.Overall 90% of men reported return of potency at 24 months, and 46% returned to baseline with normal 5-item International Index of Erectile Function scores and 100% firmness. Remarkably there was no difference in 5-item International Index of Erectile Function scores or fullness between unilateral nerve sparing and bilateral nerve sparing.

To describe our Seldinger technique of percutaneous renal cryoablation that was devised to facilitate renal biopsy, cryoprobe placement, and instillation of adjunctive hemostatics while protecting surrounding tissues from cryoinjury.This approach was used to manage 13 renal masses in 12 adult patients. Under CT-fluoroscopic guidance, an access needle was inserted to abut the surface of the tumor, followed by an Amplatz super-stiff guidewire and a customized coaxial catheter system, which was used as a conduit for needle biopsy, cryoprobe insertion, and FloSeal instillation. In addition, a porcine model was used to compare the temperature readings adjacent to the sheathed and the unsheathed cryoprobe during percutaneous renal cryoablation.In all patients, the use of this access approach was accomplished without incident. Two patients needed blood transfusions. No patient had significant skin, muscle, or nerve debility. At a mean follow-up of 11 months, none had evidence of persistent disease on CT or MRI contrast imaging. In the porcine model, the customized sheath protected the surrounding tissues from reaching temperatures below 5 degrees C while temperatures down to -15 degrees C were obtained when no insulating sheath was used.A modified Seldinger technique enabled us to perform percutaneous renal cryotherapy through a single access channel, which facilitated access for biopsy, cryoprobe placement, and instillation of hemostatic agents. This approach may provide a protective barrier against cryogenic damage to neighboring tissues and could theoretically help minimize the chance of tract seeding.

We reviewed our 4-year experience with percutaneous cryoablation and laparoscopy for treating small renal masses.After institutional review board approval we retrospectively analyzed renal cryoablation procedures performed between March 2003 and October 2007. An in-depth analysis was performed concerning demographics, hospital course and short-term outcome with respect to percutaneous vs laparoscopic cryoablation.A total of 37 patients underwent treatment for 43 renal masses. Of the 37 patients 19 underwent laparoscopic cryoablation (24 tumors) and 18 underwent percutaneous cryoablation (19 tumors) using computerized tomography fluoroscopy. For percutaneous cryoablation a saline instillation was used in 58% of cases to move nonrenal vital structures away from the targeted renal mass. There were 5 cases of hemorrhage requiring transfusion, all of which were associated with the use of multiple cryoprobes. The transfusion rate in the percutaneous and laparoscopic cryoablation groups was 11.1% and 27.8%, respectively. Operative time was significantly longer in the laparoscopic cryoablation group compared to the percutaneous cryoablation group at 147 (range 89 to 209) vs 250.2 (range 151 to 360) minutes, respectively. The overall complication rate (including transfusion) was lower in the percutaneous cryoablation group compared to the laparoscopic cryoablation group (4 of 18 [22.2%] vs 8 of 20 [40%], respectively). Hospital stay was significantly shorter in the percutaneous vs laparoscopic cryoablation group at 1.3 vs 3.1 days, p0.0001, respectively. Narcotic use in the percutaneous cryoablation group was more than half that used by the laparoscopic cryoablation group (5.1 vs 17.8 mg, p = 0.03, respectively). Among patients with biopsy proven renal cell carcinoma during a median followup of 11.4 and 13.4 months in the percutaneous and laparoscopic cryoablation groups, cancer specific survival was 100% and 100%, respectively, and the treatment failure rate was 5.3% and 4.2%, respectively.Percutaneous cryoablation is an efficient, minimally morbid method for the treatment of small renal masses and it appears to be superior to the laparoscopic approach. Short-term followup has shown no difference in tumor recurrence or need for re-treatment. Of note, hemorrhage was solely associated with the use of multiple probes.

INTRODUCTION After exposure of the retropubic space, the surgeon commonly dissects the fat overlying the prostate and usually discards it. We have previously described the importance of dissecting this fat to completely visualize the dorsal venous complex (DVC) and prostatic apex. In this study, we describe a technique to dissect and remove the anterior prostatic fat pad (APF) and its anatomic and pathologic significance. TECHNICAL CONSIDERATIONS After the retropubic space was prepared, we dissected the fat overlying the puboprostatic ligaments and the DVC to fully expose these structures. The superficial branch of the DVC was then transected, and the fat was dissected cephalad to the junction with the bladder. The fat was then further dissected laterally toward the lateral pelvic sidewall. Video analysis of the lateral dissection of the fat revealed a direct link to the obturator lymph node chain, where it was transected. Pathologic analysis demonstrated that 30 (14.7%) of 204 patients had one or more APF lymph nodes, of which four were positive for metastatic prostate cancer. The cancer of 3 of these 4 patients was upstaged as a result of the detection of these positive nodes. CONCLUSIONS The dissection of the APF facilitates visualization of the apex and bladder neck. Anatomically, we have demonstrated that the APF contains lymph nodes approximately 15% of the time that are in communication with the obturator lymph node chain and DVC. We found that removal of the APF and its pathologic analysis can result in pathologic upstaging.

During nerve-sparing robot-assisted laparoscopic prostatectomy, nerve injury caused by thermal energy is a concern. Using a porcine model, we studied thermal spread and queried whether vessels such as the prostatic pedicle may act as a heat sink, reducing the spread of thermal energy.Monopolar (MP) and bipolar (BP) cautery was applied laparoscopically on the anterior abdominal wall surface of six pigs with the da Vinci robot. Using fiberoptic thermometry (Luxtron Inc. Santa Clara, CA), temperatures were recorded with and without the interposed inferior epigastric vessels to evaluate the heat sink effect.Interposition of the inferior epigastric vessels definitively demonstrated a heat sink phenomenon: at 7 mm from the MP/BP energy source, temperatures rose 10.7 degrees C to 13.8 degrees C without interposed vessels versus only 1.9 degrees C to 2.5 degrees C when vessels were interposed (P0.001).The heat sink phenomenon suggests that the prostatic vascular pedicle should be protective of the neurovascular bundle during transection of the bladder neck during laparoscopic prostatectomy.

Inguinal hernias are detected in 20% to 30% of patients undergoing radical prostatectomy. We report our experience with concomitant transperitoneal robot assisted laparoscopic radical prostatectomy and intraperitoneal inguinal herniorrhaphy using prosthetic mesh.A retrospective review was performed of the medical records of 533 consecutive robot assisted laparoscopic radical prostatectomies performed by 1 surgeon from June 2002 to April 2007. All cases that included combined herniorrhaphy were recorded in a prospective database, reviewed and compared against a cohort of patients matched for body mass index and age who underwent robot assisted laparoscopic radical prostatectomy alone.A total of 49 concurrent herniorrhaphy procedures were performed in 40 patients for 31 unilateral (left side in 30 and right side in 19) and 9 bilateral inguinal hernias. Five patients underwent prior ipsilateral inguinal herniorrhaphy, and 3 each underwent contralateral and prior bilateral repair. Preoperatively 15 of 40 patients (37.5%) had a definite inguinal hernia, 5 (12.5%) had noticeable weakness of the external ring and 20 (50%) had a completely normal physical examination. Compared with a matched cohort undergoing robot assisted laparoscopic radical prostatectomy alone there were no significant differences in smoking history, narcotic use, hospital stay or complications. Hernia repair added approximately 10 minutes of operative time. Postoperatively 1 of 49 hernias (2.0%) recurred at 4 months during a median followup of 15.3 months. There were no complications related to hernia repair.Concurrent repair of inguinal hernias during transperitoneal robot assisted laparoscopic radical prostatectomy using prosthetic mesh is technically feasible and effective, and without increased complications or morbidity.

A 57-year-old man with prostate cancer and transitional-cell carcinoma of the kidney underwent a combined robot-assisted prostatectomy and hand-assisted laparoscopic nephroureterectomy with robot assistance. We describe the initial report of this combined operation and the novel use of the da Vinci robot for extravesical bladder-cuff excision and repair.

The objective of this study was to evaluate the feasibility of bipolar transurethral resection of the prostate (TURP) in patients with very large prostate glands and significant comorbidities. Four patients with prostate glands >160 cc on preoperative volume measurement and ASA class three or higher underwent bipolar TURP with the Gyrus PlasmaKinetic system. Preoperative, operative, and postoperative parameters were studied. The results showed an average ASA class 3.25 (range: 3–4). The average preoperative prostate volume was 207.4 cc (range: 163–268). The average preoperative International Prostate Symptom Score (IPSS) and bother score was 31 and 6, respectively. Mean resection time was 163 min (range: 129–215). The weight of resected tissue and percentage of vaporized tissue was 80.8 g (range: 62–115) and 10.0% (range: 3.8–15.1), respectively. An average of 61L of saline was used (range: 48–78). The mean change in hemoglobin and serum sodium was 2.1 g/dl (range: 1.4–2.7) and 3.3 meq/l (range: 2–4), respectively. Postoperative catheter time averaged 76 h (range: 40–104). Mean length of hospital stay was 12 h (range: 4–24). The mean postoperative IPSS and bother score was 2.75 and 0.25, respectively. Bipolar TURP is a feasible alternative to simple open prostatectomy in high-risk patients with massive prostate adenomas. Prostate volume is reduced by approximately 10% due to vaporization.

In this pilot trial in piglets, the authors demonstrated the feasibility of applying robot technology to vascular microsurgery. This preliminary work suggests certain advantages of the robot, which should encourage more rigorous study for its full exploitation.

To analyze seven cases of hepatic artery pseudoaneurysm (HAP) encountered at our hospital and review the relevant literature. We searched the computerized medical record database from January 1, 1996, to September 1, 2003, to identify all cases of HAP, which we then reviewed in detail, examining etiology, findings, laboratory data, therapeutic intervention, complications, and outcome. We then compared these findings with those reported in the literature. There were five cases of HAP among 18 015 trauma and surgical admissions to the University of California Irvine Medical Center, representing an incidence of 0.03%. There were an additional two cases of HAP among 200 orthotopic liver transplants (OLT). The five HAPs not associated with OLT were preceded by blunt abdominal trauma, liver biopsy, pancreatic pseudocyst, and polyarteritis nodosa, in one patient each, and there was no apparent cause in one patient. Two patients were treated by ligation, and the patients with post-OLT HAP underwent resection and replacement with saphenous bypass grafts. Successful embolization was performed in the other three patients. Hepatic artery pseudoaneurysm is a rare but dangerous complication of both acute surgical and chronic injury to the hepatic artery. However, early diagnosis and intervention can result in an excellent long-term outcome.

Purpose: We present our experience with standard laparoscopic wedge resection of small renal tumors using a fibrin glue-oxidized cellulose sandwich for hemostasis. Materials and Methods: From May 2002 to December 2003, 15 patients underwent laparoscopic wedge resection for a total of 15 nonhilar renal masses. Renal hilar clamping was performed in 1 patient and no sutures were placed. We used ultrasonic shears and an argon beam coagulator to resect and then coagulate the tumor bed. Tisseel (Baxter Corp., Deerfield, Illinois) was applied to the resection bed, followed by a layer of oxidized, regenerated cellulose (Surgicel, Ethicon, Somerville, New Jersey) and a final layer of Tisseel. Results: Mean preoperative tumor size was 2.2 × 2.2 × 2.1 cm. Lesions were subdivided based on the percent of the lesion that extended beyond the renal parenchymal border on computerized tomography as exophytic—greater than 60% in 6 cases, endophytic—less than 40% in 4 and mesophytic—40% to 60% in 5. Mean operative time was 3.8 hours (range 3 to 5). Mean blood loss was 108 ml (range 20 to 300). No patient required blood transfusion. There was no significant difference in blood loss or change in creatinine among the endophytic, exophytic and mesophytic groups (150, 121 and 93 ml, and 0.03, 0.07 and 0.04 mg/dl, respectively). Margin status was negative in all cases (mean thickness 3.2 mm). Average hospital stay and time to the resumption of oral intake were 2.7 and 1.4 days, respectively. Conclusions: Small exophytic or mesophytic renal lesions can be safely excised laparoscopically without vessel clamping. Excellent hemostasis was achieved in each case with the newer hemostatic agents.

As the indications for topical hemostatic agents increase in urology, the question arises: what happens to these agents when they enter the urinary collecting system? To answer this question, we performed a series of in-vitro experiments mixing three hemostatic agents with normal and sanguineous urine.Four commercially available topical hemostatic products: oxidized regenerated cellulose (Surgicel; Ethicon, Somerville, NJ), fibrin sealant (Tisseel VH Kit; Baxter Health Care Corporation, Irvine, CA), gelatin matrix hemostatic sealant (FloSeal; Baxter Health Care), and polyethylene glycol (CoSeal; Cohesion Technologies, Palo Alto, CA) were studied. Human urine (10 mL) was added to samples of each substance; this was done in triplicate. The 12 sample tubes were then capped and placed on a tube shaker at slow speed and 37 degrees C. Observations regarding consistency of the material were made at 6, 12, 24, 48, 72, 96, and 120 hours (5 days). Gelatin matrix hemostatic sealant was further tested in urine with various amounts of blood or blood clot; observations were again recorded out to 5 days.Surgicel maintained its solid form when it initially came in contact with urine, but over a period of 5 days, it transformed into a mucoid substance with visible free-floating fibers. It did not dissolve completely in urine within 5 days. Gelatin matrix was immediately transformed by urine into a fine colloidal suspension that did not change over the 5 days of the study. Fibrin glue, after mixing of the two components (fibrinogen and thrombin) directly in the urine, and polyethylene glycol immediately formed a solid clot at the bottom of the test tube on contact with the urine. When the mixture of fibrin sealant was allowed to form for 15 minutes and then added to urine, it again maintained a solid form. After 72 hours, the fibrin glue became a semisolid gelatinous plug. On analysis at 5 days, the fibrin sealant clot had transformed into a cohesive mucoid gel, and the polyethylene glycol clot had not changed. The gelatin matrix hemostatic sealant, when in contact with blood or blood clot, appeared to either become part of a clot or to remain in a colloidal suspension. At 5 days, all clots had dissolved to fine particulate suspensions, and the gelatin matrix appeared as a fine suspension.Fibrin glue and oxidized regenerated cellulose maintain a solid form when initially placed in direct contact with urine and then assume a semisolid gelatinous state, which is still present at 5 days. Polyethylene glycol forms a solid clot initially and does not change after 5 days. Only hemostatic gelatin matrix remained as a fine particulate suspension in both normal and sanguineous urine. The implications of these findings with regard to sealing the renal parenchyma or small violations of the collecting system after percutaneous or laparoscopic surgery await in-vivo testing.

Our experience with 22 renal allograft ruptures (AR) in 4418 transplant recipients over a 20-yr period was reviewed. Fourteen of the 22 ruptured allografts were repaired and eight underwent nephrectomy. All of the repaired AR functioned for 1 yr and 64% functioned at 5 yr. Human leukocyte antigens (HLA) matched and living donor cohorts were predictive factors of salvage. In this large group, renal AR was frequently rescued by primary repair with excellent long-term outcome.

Introduction and Objectives: Caliceal leak after partial nephrectomy (PN) typically resolves with conservative management. However, persistent fistulae pose a formidable challenge that may require additional therapeutic actions. Methods: We describe a case of a patient with a solitary kidney who suffered a persistent urine leak following PN. A novel retrograde ureteroscopic approach was taken that utilized the combined techniques of caliceal fulguration and fibrin glue injection. Results: Imaging demonstrated resolution of the caliceal fistula at 13 months postoperatively. Conclusions: Persistent urine leak after PN remains a burdensome complication that often requires creative steps to resolve. Our case presents a solution using a novel ureteroscopic technique.

We present the first evidence for the direct detection of nickel in the photosphere of the hot DO white dwarf REJ0503$-$289. While this element has been seen previously in the atmospheres of hot H-rich white dwarfs, this is one of the first similar discoveries in a He-rich object. Intriguingly, iron, which is observed to be more abundant than Ni in the hot DA stars, is not detected, the upper limit to its abundance (Fe/He$=10^{-6}$) implying a Fe/Ni ratio a factor 10 lower than seen in the H-rich objects (Ni/He$=10^{-5}$ for REJ0503$-$289). The abundance of nickel and various other elements heavier than He were determined from GHRS spectra. We used two completely independent sets of NLTE model atmospheres which both provide the same results. This not only reduces the possibility of systematic errors in our analysis but is also an important consistency check for both model atmosphere codes. We have also developed a more objective method of determining $T_{\rm eff}$ and log g, from the He lines in the optical spectrum, in the form of a formal fitting of the line profiles to a grid of model spectra, an analogue of the standard procedure utilising the Balmer lines in DA white dwarfs. This gives the assigned uncertainties in $T_{\rm eff}$ and log g a firm statistical basis and allows us to demonstrate that inclusion of elements heavier than H, He and C in the spectral calculations, exclusively considered in most published optical analyses, yields a systematic downward shift in the measured value of $T_{\rm eff}$.

We present the first evidence for the direct detection of nickel in the photosphere of the hot DO white dwarf REJ0503 289. While this element has been seen previously in the atmospheres of hot H-rich white dwarfs, this is one of the first similar discoveries in a He-rich object. Intriguingly, iron, which is observed to be more abundant than Ni in the hot DA stars, is not detected, the upper limit to its abundance (Fe/He= 10 6 ) implying a Fe/Ni ratio a factor 10 lower than seen in the H-rich objects (Ni/He= 10 5 for REJ0503 289). The abundance of nickel and various other elements heavier than He were determined from GHRS spectra. We used two completely independent sets of NLTE model atmospheres which both provide the same results. This not only reduces the possibility of systematic errors in our analysis but is also an important consistency check for both model atmosphere codes. We have also developed a more objective method of determining Teff and log g, from the He lines in the optical spectrum, in the form of a formal fitting of the line profiles to a grid of model spectra, an analogue of the standard procedure utilising the Balmer lines in DA white dwarfs. This gives the assigned uncertainties in Teff and log g a firm statistical basis and allows us to demonstrate that inclusion of elements heavier than H, He and C in the spectral calculations, exclusively considered in most published optical analyses, yields a systematic downward shift in the measured value of Teff.

PUBLISHED, We present the ?nal calibration of the Hopkins Ultraviolet Telescope (HUT) for its ?ight during the Astro-2 space shuttle mission in 1995 March. Aspects of mission operations and instrument performance that a?ect data quality are described in detail, as are the data reduction procedures applied to the archived data. The sensitivity calibration is de?ned by a comparison between synthetic spectra and observations obtained in ?ight of the hot DA white dwarfs HZ 43, GD 71, GD 153, and G191-B2B; the synthetic spectra were calculated by D. Koester using model parameters derived from ?ts to groundbased spectra. The resulting ?ux-calibrated spectra for these stars di?er from their respective model predictions by less than 3% at all wavelengths, except at the cores of the Lyman lines where the observed line pro?les are shallower than the predicted pro?les. As an additional consistency check, the HUT spectrum of BD ]75!325 was found to di?er from the Hubble Space Telescope Faint Object Spectrograph spectrum by at most 5% in the region of overlap. The wavelength scale and spectral resolution were calibrated by observations of symbiotic stars and of the coronal star a Aur. The spectral resolution was found to vary from 1.8 to roughly 4.5 A? , depending on wavelength and on the instrument con?guration. The internal consistency of the HUT calibration provides a new and important test of white dwarf model atmospheres, as the predicted stellar spectra are more sensitive to changes in model parameters or to shortcomings in the models themselves at wavelengths shortward of 1100 A? than at longer wavelengths. Combining this result with that of the Astro-1 HUT calibration (that a synthetic spectrum of G191-B2B and laboratory ?ux standards gave results consistent within the laboratory measurement uncertainties) demonstrates that pure hydrogen white dwarfs with e?ective temperatures of 32,000E61,000 K may be used as primary ?ux standards down to the Galactic Lyman edge.

OBJECTIVES Fungal sepsis after ureteroscopy (URS) is rarely reported. We report on 2 cases of acute fungemia that developed after routine ureteroscopic stone manipulation in patients with advanced liver cirrhosis. This represents a unique and high-risk population, and, to our knowledge, these are the first such cases reported. METHODS We performed a retrospective review of the medical records of 2 patients with Child-Pugh class B and C liver cirrhosis who had undergone ureteroscopy (URS) and holmium laser lithotripsy for obstructing ureteral calculi. RESULTS The treated stones measured 10 mm and 12 mm and were at the right ureteropelvic junction and left ureterovesical junction, respectively. Both patients had had indwelling ureteral stents in place for 1 and 2 months before URS plus holmium laser lithotripsy, with negative preoperative urine cultures. Each procedure was uncomplicated, and a ureteral stent was left in situ in each case. Within 12 hours of URS, each patient became tachycardic, hypotensive, and febrile. Blood, urine (proximal to the stone), and stone cultures were positive for Candida albicans in both patients. They were both successfully treated with intravenous fluconazole and subsequently discharged from the hospital on postoperative day 12 and 13, respectively. CONCLUSIONS Patients with advanced liver disease appear to be at greater risk of fungal sepsis after otherwise uncomplicated URS and stone manipulation. Consideration should be given to prophylactic antifungal therapy, in addition to the standard antibacterial prophylaxis for such procedures.

We present an atlas of extreme ultraviolet (EUV) spectra of 95 bright stellar sources observed between 1992 July and 1996 June with the Extreme Ultraviolet Explorer (EUVE) spectrometers. These data are taken in the short- (SW; 70-190 A), medium- (MW; 140-380 A), and long-wavelength bandpasses (LW; 280-760 A) at roughly 0.5, 1, and 2 A resolution, respectively. We describe the spectrometers and detail the procedure used to reduce the observational data to spectra. The atlas is grouped by the type of source: O-A stars, F-M stars, white dwarfs, and cataclysmic variables. We present a brief overview of the general nature and EUV spectral distribution of each group and present accompanying notes and individual spectra for each source. We show selected F-M sources in more detail with identifications of the brightest spectral lines illustrating the characteristics of the EUV spectra of stars of various temperatures. The current study is the most complete compilation to date of aggregate spectra of bright EUV stellar sources.

We recently discovered PG (WD) 0922+162 to be a visual double degenerate pair, the youngest found to date. Both components have effective temperatures just above 22,000 K, a region in which detailed fitting of the Balmer line profiles from high signal-to-noise spectra provides very accurate temperatures and gravities. Spatially resolved visual double degenerates can, in principle, be used to determine the initial-final mass (Mi-Mf) relation for white dwarfs. PG 0922+162 is the first resolved double degenerate for which the physical parameters may be derived with sufficient accuracy to improve on cluster results for the Mi-Mf relation. Using Wood's WD cooling models to determine the masses, our results are that the more luminous member of the pair, PG 0922+162 A, has Teff = 22,740 ± 230 K, log g = 8.27 ± 0.05, and M = 0.79 ± 0.03 M☉, while the fainter star, PG 0922+162 B, has Teff = 22,130 ± 220 K, log g = 8.78 ± 0.05, and M = 1.10 ± 0.03 M☉. The corresponding WD cooling times are about 90 and 260 Myr, respectively. Given the lack of an independent determination of the age of the system, we cannot directly obtain the progenitor mass for PG 0922+162 B. However, previous cluster results provide plausible limits to the progenitor mass for PG 0922+162 B of 5.5-7.5 M☉, which in turn limits the age of the PG 0922+162 system to the range of about 290-350 Myr. Given that age range, we find that the initial mass of the progenitor of PG 0922+162 A must lie within the narrow range of 3.6-4.0 M☉.

Results are presented from a comprehensive spectroscopic survey of DA white dwarfs hotter than ~25,000 K. The observations consisted of CCD spectra with signal-to-noise ratios of ~100 in the blue, with ~5 A resolution. The majority of the spectra covered the wavelength range of 3500-7500 A, allowing the detection of a number of cool companions. To date, spectra have been obtained and analyzed for 174 DA stars. The spectra were analyzed using our model atmospheres, which are described in detail here, resulting in temperatures and gravities with average internal errors of 1% and 0.04 dex, respectively. Comparisons with previously published results showed that temperature determinations for Teff 1.1 M☉. The ultramassive DA's comprise a much larger fraction of the total than was the case for cooler samples. Calculations based on white dwarf evolutionary models showed that a higher proportion of massive white dwarfs is expected to be found in samples with Teff 30,000 K as a result of differential cooling effects. Within the range Teff > 40,000 K, the EUV-selected subsample did have proportionately more massive stars than the optically selected subsample. However, a detailed comparison showed that EUV and optical surveys were equally capable of detecting relatively nearby massive white dwarfs. On the other hand, interstellar EUV absorption eliminated from the EUV sample many of the more distant stars that were detectable optically. Therefore, the apparent excess of massive DA white dwarfs in the EUV sample is largely due to a relative deficit of stars with more typical masses. Results are presented for individual stars, including a number of subdwarf identifications and reports of detections of cool companions. Properties of some of the more interesting binaries are discussed. We also report on some stars in the sample that evidently have varying He abundances. WD 0612+177 (G104-27) had been observed, at one point, to have photospheric He I; we confirm that He has remained absent since then. WD 0718-316 (RE 0720-314) is in a post-common-envelope binary and has photospheric He II, the abundance of which appears to vary by more than an order of magnitude over timescales of months.

We present the final calibration of the Hopkins Ultraviolet Telescope (HUT) for its flight during the Astro-1 space shuttle mission in 1990 December. The calibration is defined by a comparison between an observation obtained in flight of the hot DA white dwarf G191-B2B and the model atmosphere for this star calculated by P. Bergeron. We also present the postflight laboratory calibration of the HUT sensitivity, which we find to be in excellent agreement with the white dwarf calibration. The ratio of the white dwarf to the laboratory effective area calibration has a mean value of 1.0044 over the wavelength range 912-1840 A, a slope of 7.61 × 10-6 A-1 (which corresponds to a relative difference of only 0.35% at either end of the spectrum), and fluctuations about the mean value with an rms amplitude of 3%. The uncertainties in the laboratory calibration are 4% for the overall normalization, 5% relative to the mean on wavelength scales of 50 to several hundred A, and an uncertainty in the overall slope that corresponds to 1% at 1840 A and that increases smoothly to 3% at 912 A. These results validate the use of white dwarf models as absolute flux standards in the far-ultraviolet, especially for wavelengths shortward of Lyα, where previous experiments often disagreed by large factors. In particular, the normalization and wavelength dependence of the sensitivity calibration adopted by the Hubble Space Telescope Faint Object Spectrograph is confirmed to within the uncertainties of our laboratory calibration, while the normalization of the IUE final calibration is found to be low by an amount just exceeding our 1 σ uncertainty. Fits to the spectra of both G191-B2B and the hot DA white dwarf HZ 43 yield effective temperatures and surface gravities in good agreement with values derived from Balmer line profiles. We also present a comparison with Voyager spectra for the stars G191-B2B, HZ 43, BD +28°4211, π Aqr, and HD 25443. When averaged over broad bands (912-1050 A, 1050-1180 A), fluxes from the two instruments typically agree to within 10%.

The Extreme Ultraviolet Explorer (EUVE) observatory, successfully launched on 1992 June 7, provided astronomers with the first observatory dedicated to observation in the extreme ultraviolet. The scientific objectives of EUVE include an all-sky survey in four spectral bands, a deep survey in two spectral bands, and a spectroscopic survey carried out through a NASA guest observer program. We describe here the hardware components of the four telescopes used to carry out both the all-sky survey and the deep survey, and we present the imaging and photometric performance characteristics of the instruments as determined from ground calibration and in-orbit data.