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Assaad El-Hakim

Publications and source records attributed to Assaad El-Hakim.

15 recordsLinked to original sources
PubMed2006

Identification of the retrotrigonal layer as a key anatomical landmark during robotically assisted radical prostatectomy.

OBJECTIVE: To define the gross and microscopic anatomy, and the surgical significance, of the newly described retrotrigonal layer of the bladder neck, as an aid during robotic radical prostatectomy (RRP). MATERIALS AND METHODS: The data for this study were obtained from five fresh cadaveric dissections and 100 consecutive RRPs. Five male cadavers with no previous pelvic or urethral surgery were dissected to expose the posterior bladder neck and identify the retrotrigonal layer. This same layer was reproducibly identified in all 100 RRPs. The gross appearance of this layer, and its relationship to neighbouring structures, was documented using still photographs and intraoperative video. The microscopic composition of this layer was assessed using routine haematoxylin and eosin stains, and special staining for smooth muscle (desmin), neural tissue (S-100), and elastin. RESULTS: Grossly, the retrotrigonal layer is a well-defined midline strip located posterior to the bladder neck, that extends from the trigone (superiorly) to the base of the prostate (inferiorly). Microscopically, this layer was predominantly composed of smooth muscle with intervening connective tissue. The retrotrigonal layer serves as a key anatomical landmark to facilitate posterior prostatic dissection, particularly in men with large prostates, prominent median lobes, or previous transurethral prostatic surgery. Further, in our practice, this layer marks the posterior limit of dissection in which electrocautery is still used. Finally, the retrotrigonal layer serves to buttress the posterior layer of the urethrovesical anastomosis. CONCLUSION: The retrotrigonal layer is a key landmark during the posterior bladder neck dissection in the antegrade technique of RRP.

Adult↗
PubMed2006

Athermal Robotic Technique of prostatectomy in patients with large prostate glands (>75 g): technique and initial results.

OBJECTIVE: To report our experience with robotic radical prostatectomy (rRP) for prostate glands of >75 g, as this technique is developing rapidly. PATIENTS AND METHODS: Between January 2005 and November 2005, 30 men with prostates of >75 g had rRP. Their clinicopathological and operative data were reviewed. Technical considerations for successful rRP in patients with large glands are discussed, including the importance of surgical exposure and multiple traction sutures. RESULTS: The mean (range) specimen weight was 116.1 (75.3-346.0) g, the patient age 65.0 (56-72) years, the body mass index 28.4 (21-41) kg/m2, the preoperative International Prostate Symptom Score 10 (0-32), and the prostate-specific antigen (PSA) level 7.54 (1.9-20.1) ng/mL. The clinical stage was T1c in 26 men and T2a in four. The biopsy Gleason scores were 3 + 3 = 6 in 25 men, 3 + 4 = 7 in four and 4 + 3 = 7 in one. The mean (range) estimated blood loss was 208 (100-600) mL and the operative duration 193 (150-270) min. The cancer was organ-confined in all patients and all surgical margins were negative. The mean (range) duration of indwelling catheterization was 12.7 (11-14) days. There were no complications during or after rRP, and the PSA level was undetectable in all patients after surgery. CONCLUSIONS: RP for patients with large prostates is technically challenging. The robotic approach does not appear to compromise oncological control. We show the feasibility of rRP for men with large glands.

Aged↗
PubMed2006

Robotic prostatectomy: a pooled analysis of published literature.

OBJECTIVE: Robotic prostatectomy has been recently added to the treatment armamentarium of localized prostate cancer. We reviewed published data on this modality with critical appraisal of outcomes and complications. METHODS: A Medline search was performed that encompassed all published articles on robotic prostatectomy. Select data on open radical retropubic (RRP) and laparoscopic (LP) prostatectomy from centers of excellence in the USA and Europe were included for objective comparison. Perioperative parameters, pathological results, including surgical margin rate, complications and postoperative continence and potency rates were reported. Advantages and shortcomings of robotic prostatectomy, and the learning curve and cost issues were also addressed. RESULTS: Robotic prostatectomy offers advantages of minimally invasive access surgery, including enhanced visualization, decreased bleeding and transfusion rate, shorter hospital stay and faster recovery. Pathological outcomes are comparable to RRP and LP with acceptable positive margin rate. At short-term follow-up, continence and potency results appear to be equivalent to RRP and LP. The learning curve of robotic prostatectomy is faster than that of LP. Cost remains a matter of debate at the present time. Long-term cancer control results of robotic prostatectomy are still maturing. CONCLUSIONS: Robotic prostatectomy is a promising minimally invasive surgical approach for men with localized prostate cancer. Short-term clinical and pathological results compare favorably to RRP and LP.

Humans↗
PubMed2005

First prize: ureteral segmental replacement revisited.

BACKGROUND AND PURPOSE: Long strictures of the proximal ureter are difficult to manage, and circumferential replacement with various natural and synthetic materials has been unsuccessful. We sought to use cultured autologous cells seeded onto graft material for proximal-ureteral replacement. Additionally, we wished to determine if urothelial cell-seeded de-epithelialized small bowel would generate adequate ureteral replacement. MATERIALS AND METHODS: Three sets of experiments were performed. First, autologous pig-bladder smooth-muscle and urothelial cells were expanded in culture on large sheets of multilayer small-intestinal submucosa (SIS). These sheets were then tubularized and used to replace a 5-cm segment of proximal ureter in pigs. Second, autologous cells harvested from the bladders of Beagle dogs were cultured and seeded on porcine ureteral acellular matrix, which was used to replace a 3-cm segment of ureter in dogs. Segments were wrapped in omentum to enhance vascularity. Third, a de-epithelialized small-bowel segment seeded with autologous bladder-epithelial cells was transversally retubularized (Monti) into a 4-cm ureteral replacement. Follow-up studies consisted of retrograde pyelography, serum chemistry assays, hematoxylin/eosin studies, and immunohistopathologic examination using antibodies against alpha-smooth-muscle actin and pancytokeratin AE1-AE3. RESULTS: Coculture of urinary-tract cells on large segments of SIS failed to create adequate ureteral replacement. All grafts were contracted and stenotic, with complete obstruction of the ipsilateral renal unit. Similar results were seen in the Beagles. Despite clinical obstruction and gross contraction of the graft, a circumferential muscular ureteral wall lined with multilayer transitional epithelium was present. Urotheliumseeded de-epithelialized Monti bowel segments resulted in patent ureteral replacement without hydroureteronephrosis and with normal renal function, serum electrolytes, and acid-base balance. However, bowel mucosa fully regenerated, with multilayer transitional epithelium growing adluminally in continuity with the proximal and distal anastomotic sites. CONCLUSIONS: Seeding of ureteral grafts with autologous bladder cells does not promote success in two largeanimal models using different xenogenic acellular matrices. However, muscle and urothelium regeneration occurs with ureteral acellular matrix in the dog. Urothelium-seeded de-epithelialized Monti bowel segments may be an acceptable substitute for long proximal ureteral segments. Further technical refinements are required to replace the bowel mucosa completely with normal urothelium.

Animals↗
PubMed2004

Robotic prostatectomy - a review.

OBJECTIVE: To review the current medical literature on robotic prostatectomy (RP) and report clinical outcomes of this newly developed technique. DATA SOURCE: A MEDLINE search was performed using the following headings: prostate cancer, radical prostatectomy, robotics, robot assisted, laparoscopy, telesurgery. In addition, recently published abstracts on RP were reviewed. STUDY SELECTION: Studies that reported clinical and pathological variables of patients undergoing RP were included in this meta-analysis. DATA EXTRACTION: Data were extracted from published articles and abstracts. DATA SYNTHESIS: Robotic systems enhance surgeons' technical abilities and offer the potential of precise surgical technique. Short-term follow-up studies demonstrate that RP is at least comparable in efficacy to open and laparoscopic prostatectomy, including clinical and pathologic parameters. RP has benefits of minimal invasiveness, decreased blood loss, and quicker recovery compared with open surgery. Functional and cancer control results are still immature, but most studies reported favorable outcomes. CONCLUSIONS: RP is a promising minimally invasive surgical approach for men with prostate cancer. Short-term clinical and pathological results are comparable to those with open and laparoscopic prostatectomy.

Humans↗
PubMed2004

Correlation of ureteroscopic appearance with histologic grade of upper tract transitional cell carcinoma.

OBJECTIVES: To correlate urologists' impressions of the tumor grade of upper tract tumors at ureteroscopy with the histologic findings after biopsy or resection. METHODS: A retrospective review of all patients who underwent diagnostic or therapeutic ureteroscopy for upper tract transitional cell carcinoma (TCC) between 1992 and 2002 was performed. Only patients who had proven TCC with a descriptive narration of the urologists' impressions of tumor grade and a representative pathologic specimen were included. The urologist's impression of tumor grade was reported as low or high grade according to the operative report and was correlated with the histologic grade. A total of 40 tumors met inclusion criteria. RESULTS: Ureteroscopy classified 28 tumors as low grade, 10 as high grade, and 2 as benign. The histologic findings of the 28 tumors believed to be low grade on ureteroscopy showed that 20 (71%) were grade 1-2, and of the 10 tumors believed to be high grade, 8 (80%) were actually grade 3-4. The overall accuracy of ureteroscopy in predicting the tumor grade of upper tract TCC was 70%. The benign-appearing lesions proved to be malignant. CONCLUSIONS: The urologists' impressions of tumor grade on ureteroscopy were relatively good. However, visual assessment alone was inaccurate in 30% of the cases in our series. Therefore, we believe that biopsies remain essential for accurate grading of upper tract TCC. Therapeutic decisions should not be based solely on visual ureteroscopic assessment of tumor appearance.

Biopsy↗
PubMed2004

Chronic prostatitis/chronic pelvic pain syndrome: is there a role for local drug infiltration therapy?

The clinical syndrome of chronic prostatitis ranges from well-defined chronic bacterial infections to poorly defined chronic pelvic pain syndrome (CPPS), previously referred to as "prostatodynia" or "abacterial prostatitis." Faced with the obscure nature of the disease, its protracted course, and the poor response to oral medication, urologists have considered alternative routes of drug administration. We review the indications and outcomes of local drug infiltration (intraprostatic antibiotic and zinc, intrasphincteric botulinum toxin A, pudendal nerve blocks) and discuss their potential use and benefit in the treatment of chronic prostatitis syndromes.

Anti-Bacterial Agents↗
PubMed2004

Peritoneal and systemic inflammatory mediators of laparoscopic bowel injury in a rabbit model.

PURPOSE: Unrecognized bowel injury following laparoscopy has a subtle and delayed clinical presentation compared with that after open surgery. We determined peritoneal and systemic immune function in laparoscopic and open bowel injury cases. We propose that laparoscopy does not activate immune responses to the same extent as open surgery. MATERIALS AND METHODS: A total of 40 rabbits were divided into 4 groups. Two study groups were subjected to laparoscopic and open bowel injury, and 2 control groups underwent pneumoperitoneum and sham open surgery, respectively, without bowel injury. Animals were sacrificed 1 day, 3 days and 1 week postoperatively. Macroscopic and histological findings were analyzed. Peritoneal fluid, systemic white blood count (WBC) and differentials were done with a hemocytometer. Peritoneal fluid and serum interleukin (IL)-8 concentrations were measured by enzyme-linked immunosorbent assay. RESULTS: Macroscopic and histological findings were indistinguishable in the 2 study groups. However, study groups demonstrated higher peritoneal WBCs than their respective controls at 1 and 3 days (p <0.05). Peritoneal WBC was lower in the laparoscopy than in the open study group at 3 days (p <0.05). There was a significant decrease in peritoneal lymphocytes and monocytes in the laparoscopic vs the open study group at 3 days. No differences were found in systemic WBC or differentials among all groups. Peritoneal IL-8 concentrations were higher in the laparoscopic bowel injury than in the laparoscopic control group at 1 and 3 days (p <0.05). However, there were no differences in peritoneal or serum IL-8 concentrations between both study groups. CONCLUSIONS: Laparoscopic surgery seems to be unable to sustain peritoneal immune responses, which may mask reliable clinical signs and symptoms of peritonitis associated with bowel injury.

Animals↗
PubMed2004

Comparison of laparoscopic saline infused to dry radio frequency ablation of renal tissue: evolution of histological infarct in the porcine model.

PURPOSE: We investigated and compared the gross and histopathological features of radio frequency (RF) ablated renal tissue using saline infused RF ablation (RFA) vs dry RFA in a porcine model. MATERIALS AND METHODS: Ten porcine kidneys underwent laparoscopic RFA. The lower and upper poles of each right kidney were treated with 1 and 2 cycles of saline augmented (wet) RFA, respectively. The upper pole of each left kidney was RF ablated without saline infusion (dry RFA) and a control lesion was created in the lower pole. The animals were sacrificed immediately after ', 2 and 9 days after (subacute), and 14 and 21 days after (chronic) treatment, respectively. Gross pathological and histological changes caused by the different RF treatments were compared. RESULTS: Mean time to attain target temperature was shorter with wet than with dry RFA. Grossly the lesion sizes achieved were larger using wet RFA but independent of the number of wet RFA treatment cycles. Gross lesion sizes decreased with time for each treatment modality. No histopathological differences were seen between the 2 RFA treatment modalities as well as between 1 vs 2 cycles of wet RFA. In the acute phase hematoxylin and eosin staining of ablated tissue revealed focal areas of alterations in renal tubular histology. However, nicotinamide adenine dinucleotide staining of corresponding areas confirmed the lack of cellular viability except for glomeruli. In the subacute phase there were focal coagulation necrosis and thrombosed blood vessels. Within the necrotic areas the glomeruli were the last structures to lose viability. In the chronic phase fibrosis with decreased lesion size was seen. Nicotinamide adenine dinucleotide staining demonstrated that the cellular kill was permanent during the entire study period. CONCLUSIONS: The effects of RFA of renal tissue has 2 phases, namely initial direct thermal ablation causing acute cell death and a later subacute phase causing subsequent infarction of the distal arterial vascular supply to the ablated region, resulting in more cell death and coagulative necrosis. Glomeruli are the last structures to lose viability in necrotic areas. Most importantly cellular death caused by RFA is permanent.

Animals↗
PubMed2003

Electrical prostate morcellator: an alternative to manual morcellation for laparoscopic nephrectomy specimens? An in vitro study.

OBJECTIVES: To compare the safety and efficacy of morcellation with the electrical prostate morcellator (EPM) or manual morcellation of the kidney, using an internal view within the morcellation sac. METHODS: Thirty porcine kidneys, mean renal mass 174.5 g, were divided into three groups of 10. All morcellations were performed inside the LapSac. Groups 1 and 2 underwent morcellation using the EPM, monitored inside the LapSac using the nephroscope and outside the LapSac with the laparoscope, respectively. Group 3 underwent manual morcellation with ring forceps. The groups were assessed for morcellation time, fragment size, and LapSac integrity. RESULTS: In group 1, one pinhole perforation occurred; in group 2, nine perforations occurred (five large and four pinhole). No perforations occurred (P <0.001) in group 3 (manual morcellation). The mean morcellation time for groups 1 through 3 was, respectively, 86.9, 47.1, and 15.1 minutes (P <0.0001). The corresponding mean fragment size was 0.011, 0.015, and 1.36 g. The difference in mean fragment size was significantly different between the manual morcellation group and the EPM groups (P <0.001), but not between the two EPM groups (P = 0.12). CONCLUSIONS: Manual morcellation was safe, fast, and superior to morcellation with the EPM monitored either inside or outside the LapSac. The high rate of LapSac perforation precludes the use of EPM after laparoscopic radical nephrectomy in the clinical forum.

Animals↗
PubMed2003

Comparison of the mechanical, flow, and optical properties of contemporary flexible ureteroscopes.

OBJECTIVES: New designs have improved the ability of flexible ureteroscopes to assess the upper urinary tract. However, limitations of tip deflection may interfere with diagnosis and treatment of lower pole renal pathologic features and smaller working channels may impair irrigant flow. Our purpose was to compare the new flexible ureteroscopes with prior models to determine whether engineering advances have overcome these problems. METHODS: Two newly released flexible ureteroscopes, the ACMI DUR-8 Elite and the Storz 11278AU, were compared with four other ureteroscopes, the ACMI DUR-8, Storz 11274AAU, Olympus URF-P3, and Wolf 9F. Active tip deflection, irrigation flow rates, and intraluminal pressures with and without various endoscopic tools were assessed. The specifications, purchase prices, and repair costs were obtained from the individual manufacturers. Also, the field of view and screen image size of each scope were compared. RESULTS: The ACMI DUR-8 Elite and Storz 11278AU had improved tip deflection of 79 degrees and 144 degrees, respectively, from previous ureteroscopes. Although the tip deflections of all ureteroscopes were compromised by the insertion of endoscopic tools, new ureteroscopes were less affected. With a 3F basket within the working channel, the ACMI DUR-8 Elite and the Storz 11278AU had a loss of downward deflection of only 0.7% and 2.8% compared with a loss of 9.6% and 5.0% for their older models, respectively. However, the flow rate of these new instruments was decreased. CONCLUSIONS: The new flexible ureteroscopes have significantly better active tip deflection than previous models, both with and without endoscopic instrumentation inserted. However, improved flexibility comes at the expense of a decreased flow rate.

Equipment Design↗
PubMed2003

Immune response to laparoscopic bowel injury.

BACKGROUND AND PURPOSE: Laparoscopic bowel injuries are rare but potentially fatal if recognition is delayed. Unlike the situation after open surgery, patients with unrecognized bowel injury after laparoscopy do not present with the typical "acute surgical abdomen." We investigated monocyte, neutrophil, and lymphocyte apoptosis as indicators of the immune response and whether this response is stimulated or suppressed by laparoscopic bowel injury compared with bowel injury induced during open surgery. MATERIALS AND METHODS: After an animal protocol was approved, laparoscopy was performed in a rabbit model. A total of 44 animals were divided into four groups of 11 rabbits each. Laparoscopic bowel injury was created using 30-W electrocautery at 0 (control), 1, and 5 hours after induction of pneumoperitoneum. Bowel injury was created in the fourth group during open laparotomy. Animals were euthanized at 0, 1 day, 1 week, or 2 weeks after surgery. Apoptosis was assessed by staining the nuclei of blood cells with H-33342 dye. RESULTS: At 1 week, neutrophil, monocyte, and lymphocyte apoptosis levels were 2.4- to 5-fold lower after laparoscopy (1-hour pneumoperitoneum) compared with open surgery. However, at 2 weeks, the percentage of apoptosis had equalized in the two groups. Interestingly, with longer laparoscopic procedures (5 hours), the percentage of apoptosis at 0 and 1 day more closely approached that seen after open surgery. At 2 weeks, there was a significant difference in apoptosis levels in all cell types between the experimental groups compared with controls (P < 0.001). No animals undergoing a 5-hour open procedure survived to 2 weeks after bowel injury. CONCLUSIONS: Open surgery resulted in a significant increase in programmed cell death compared with controls in the immediate postoperative period following bowel injury. Laparoscopic surgery produced a delayed response and after 2 weeks with bowel perforation approached open surgery levels. The difference in the degree of cellular death may be secondary to a smaller degree of stimulation of the immune response in laparoscopic surgery.

Analysis of Variance↗
PubMed2003

Residual air persists in the renal collecting system following percutaneous nephrolithotomy.

OBJECTIVES: To determine the presence or absence of air in the renal collecting system 48 hours following percutaneous nephrolithotomy (PCNL). METHODS: The study was based on a review of the records of the last 100 consecutive patients undergoing PCNL for stone extraction. Two urologists and a uroradiologist reviewed post-PCNL nephrostogram films and determined the presence or absence of air in the urinary tract. RESULTS: Nephrostography was routinely performed 48 hours after PCNL, and all films of the 100 patients were reviewed. Gas was detected in 98 (98%) of the 100 cases that appeared as gas pyelograms outlining the renal calyces. Of the 98 cases, 33 (34%) demonstrated gas in the upper calyx, 10 (10%) in the middle calyx, 12 (13%) in the lower calyx, and 43 (44%) in more than one calyx. Gas was not detected in the renal parenchyma or perirenal areas. CONCLUSIONS: Gas is present within the renal collecting system 48 hours after a percutaneous procedure. Prospective studies should be performed to document the amount of time needed for complete resolution of gas from the collecting system.

Adult↗