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Karim Touijer

Publications and source records attributed to Karim Touijer.

11 recordsLinked to original sources
PubMed2007

The anterior layer of Denonvilliers' fascia: a common misconception in the laparoscopic prostatectomy literature.

PURPOSE: Incision of the anterior layer of Denonvilliers' fascia is commonly cited as a key step in successful dissection of the vasa deferentia and seminal vesicles from the posterior bladder neck during laparoscopic radical prostatectomy. However, anatomical descriptions do not support the presence of Denonvilliers' fascia anterior to the seminal vesicles. To address this inconsistency we performed a detailed anatomical study of tissue planes encountered during laparoscopic dissection of the posterior bladder neck. MATERIALS AND METHODS: To grossly characterize the tissue planes encountered during laparoscopic posterior bladder neck dissection, ex vivo dissections were performed on 4 separate cystoprostatectomy specimens. Biopsies of the representative areas were obtained from 20 consecutive laparoscopic radical prostatectomy specimens by 2 dedicated uropathologists. RESULTS: Following incision into the posterior bladder neck mucosa, longitudinally oriented fibers were readily visualized, extending from bladder neck to prostate base. Histologically this anatomical landmark represents the fusion of 2 separate tissue layers, that is an inner lamella composed of longitudinally disposed smooth muscle fibers in continuation with the longitudinal fascia of the bladder detrusor (medial fascicle of the detrusor running in between the ureters) and an outer lamella composed of fibroadipose tissue in continuation with the bladder adventitia. CONCLUSIONS: Our anatomical and histological analysis refutes the prevailing belief in the laparoscopic literature that the longitudinal muscle fibers identified during dissection of the posterior bladder neck represent the anterior layer of Denonvilliers' fascia. They correspond to the posterior longitudinal fascia of the detrusor muscle that is externally upholstered by the bladder adventitia.

Fascia↗
PubMed2006

Risk-adjusted analysis of positive surgical margins following laparoscopic and retropubic radical prostatectomy.

OBJECTIVES: To prospectively compare in a contemporary and contemporaneous series the positive surgical margin (PSM) rate between laparoscopic (LRP) and retropubic (RRP) radical prostatectomy at the same institution. METHODS: Between 1 January 2003 and 30 June 2005, 1177 consecutive men with clinically localized adenocarcinoma of the prostate underwent radical prostatectomy at the same institution: 485 laparoscopically and 692 through a retropubic approach. Partin table probability of organ-confined (OC) disease was used as an index of disease aggressiveness: The PSM rate between the two approaches was compared, with adjustment for the OC probability. RESULTS: Overall both surgical approaches had a comparable PSM rate of 11.3% after LRP and 11% after RRP. In a logistic regression analysis adjusting for OC probability, there was no statistically significant difference between LRP and RRP (odds ratio [OR]: 1.156; 95% confidence interval [%95 CI], 0.792, 1.686; p=0.5). There was a statistically significant decrease over time in the rate of PSM for LRP (OR: 0.71 per 100 patients treated; %95 CI, 0.57, 0.89; p=0.003), while that of RRP was unchanged (OR: 1.06 per 100 patients treated; %95 CI, 0.94, 1.21; p=0.3; p=0.002 for interaction between change over time and procedure). CONCLUSIONS: In our institution, laparoscopic and retropubic radical prostatectomy provide comparable PSM rates for patients with clinically localized prostate cancer. The PSM rate over the study period remained unchanged in the RRP experience, indicating a mature and well-established operative technique, while that of LRP underwent a significant decrease, demonstrating that the procedure and therefore the results continued to evolve during the study.

Adenocarcinoma↗
PubMed2006

Preoperative and intraoperative risk factors for side-specific positive surgical margins in laparoscopic radical prostatectomy for prostate cancer.

OBJECTIVES: Identification of variables predicting positive surgical margins (PSMs) in patients undergoing laparoscopic radical prostatectomy (LRP) for clinically localized prostate cancer is lacking. Our objective was to determine preoperative risk factors and the association of ipsilateral degree of neurovascular bundle dissection (intraoperative factor) with side-specific PSMs in these patients. MATERIAL AND METHODS: Between October 2002 and April 2005, one surgeon performed LRP on 407 previously untreated patients. Of 814 evaluable prostate sides, 728 harboured prostate cancer in the specimen and composed the study population. For each prostate side, we obtained clinical stage, biopsy Gleason, maximum percentage of tumour in the biopsy, suspected extracapsular extension (ECE) on endorectal coil magnetic resonance imaging (MRI), degree of neurovascular bundle (NVB) dissection, and PSMs. PSM was defined as cancer cells at the inked margins. Logistic regression analyses with random effects were generated. RESULTS: Of the 728 prostate sides with cancer, 51 (7%) had at least one PSM. In multivariable analysis, higher PSA (p=0.01), Gleason score of 7 compared with < or =6 in the biopsy (p=0.04), lower prostate volume on MRI (p=0.01), and interfascial NVB dissection compared with intrafascial dissection (p=0.01) were associated with an increased risk of side-specific PSMs. Suspected ECE on MRI (p=0.9) and clinical stage (p=0.3) were not significantly associated with side-specific PSMs. A subset analysis of 321 patients with bilateral tumours did not show statistically significant differences in PSMs according to tumour side (p=0.3). CONCLUSIONS: High serum prostate-specific antigen, biopsy Gleason score of 7, low prostate volume, and interfascial NVB dissection were independently associated with side-specific PSMs after LRP, and should be considered during planning of the LRP surgical strategy.

Aged↗
PubMed2006

Anatomy and preservation of accessory pudendal arteries in laparoscopic radical prostatectomy.

OBJECTIVE: The incidence of laparoscopically diagnosed accessory pudendal arteries (APAs) varies depending on how proactive the surgeon is to find them. Their preservation depends on their calibre and location. Our objective was to provide a detailed description of how to identify, dissect, and preserve APAs during laparoscopic radical prostatectomy (LRP). METHODS: Between January 2003 and January 2005, we treated 377 men with LRP; 325 met inclusion criteria for this study. We defined an APA as any artery located within the periprostatic region running parallel to the dorsal vascular complex and extending caudally towards the anterior perineum, other than cavernous arteries, corona mortis, and satellite arteries to the superficial and deep vascular complex. Two distinct varieties of APAs were identified: (1) lateral APAs course along the lateral aspect of the prostate and branch off any of the terminal branches of the hypogastric artery; and (2) apical APAs emerge through the levator ani fibres near the apical region of the prostate and most likely branch off the pudendal artery or corresponds to an aberrant course of the pudendal artery itself. We present a video depicting the laparoscopic anatomy of APAs and the technique to preserve them. RESULTS: Ninety-six of 325 men (30%) were found to have 125 separate APAs. Using the depicted surgical technique, we were able to preserve 83% of all APAs. Forty-nine of 55 lateral APAs (89%) and 55 of 70 apical APAs (79%) were preserved. Thirty-five of 38 large-calibre APAs (92%) and 70 of 87 small-calibre APAs (80%) were spared. The side-specific incidence of PSMs were 3% and 6% when APAs were preserved and not preserved, respectively (p=0.5). CONCLUSIONS: APAs are frequently identified during laparoscopic prostatectomy. Their preservation is feasible in LRP without increasing the risk of causing a PSM. It is reasonable to integrate APA preservation as part of the modern radical prostatectomy, although their role in functional outcomes still needs to be prospectively established.

Arteries↗
PubMed2006

Laparoscopic radical prostatectomy: a critical analysis of surgical quality.

OBJECTIVE: To review the literature and answer the question of whether the laparoscopic approach meets the quality standards. METHODS: We conducted an extensive Medline literature search. The articles obtained and the experience at Memorial Sloan-Kettering Cancer Center were used for interpretation and critical analysis of results. Long-term quality indicators are oncologic efficacy, potency rate, and continence rate. Short-term quality indicators are blood loss and transfusion rate, hospital stay, postoperative recovery, and rate and severity of complications. RESULTS: Long-term quality indicators. Oncologic efficacy. Despite recent evidence that pelvic lymph node dissection (PLND) at radical prostatectomy may be necessary to detect occult positive lymph nodes, and that extended node dissection may also have a positive impact on disease-free survival, PLND is rarely performed during laparoscopic radical prostatectomy (LRP), which may have a negative impact on the long-term recurrence-free probability. Positive margins rates range from 11% to 26%, ranging from 6% to 8% for organ-confined disease and from 35% to 60% in those with extraprostatic extension. Most of these data include the first patients operated on when the technique of LRP was in early development. These rates seem high as compared to the contemporary data achieved in retropubic radical prostatectomy. Short-term biochemical recurrence rate have been published by only two centers and generalization to the whole laparoscopic patients and to long-term results are at present time hazardous. Functional outcome. Given the complexity of measuring, interpreting, and reporting continence and erectile dysfunction, the available results after LRP do not allow drawing any conclusion. Furthermore, the number of patients on whom results are reported is disproportionately low in relation to the large LRP experience accumulated so far. Short-term quality indicators. Assessment of LRP equanimity includes factors such as blood loss, transfusion rates, hospital stay, duration of catheterization, and complication profile. All the reports are concordant and demonstrate a benefit for the laparoscopic approach. However, no prospective and parallel studies compare the respective advantages of LRP and radical retropubic prostatectomy in reference centers. CONCLUSIONS: In a review of the published literature results of LRP, there is not enough evidence to answer the question of whether the laparoscopic approach meets the quality standards. The available biochemical recurrence information is promising but limited to the short-term and the experience of two centers only. The question of omitting the PLND or performing a limited one in high-risk patients needs to be answered. The functional results analyses suffer from a lack of uniformity in methodology, a limited follow-up, and a disproportionately small number of patients in relation to the accumulated experience. Future reports of the post-learning phase era are dramatically needed.

Humans↗
PubMed2006

Impact of a multidisciplinary continuous quality improvement program on the positive surgical margin rate after laparoscopic radical prostatectomy.

OBJECTIVE: Outcome after radical prostatectomy is highly sensitive to fine nuances in the surgical techniques. We sought to determine the impact of a process of continuous control and monitoring on the positive surgical margin rate in a contemporary series of laparoscopic radical prostatectomy. METHODS: Between January 2003 and October 2004, 301 men underwent laparoscopic radical prostatectomy for clinically localized prostate cancer (cT1-cT3a). A weekly case review conference involving surgeons, radiologists, and uropathologists was held to discuss the preoperative, intraoperative, and pathologic findings of significant cases. We analyzed the trend of positive surgical margins and compared the clinical and detailed pathologic characteristics of the cancer during the study period. RESULTS: We created logistic regression models with positive margin as the dependent variable and surgical experience as the predictor, adjusting for possible secular changes in disease severity (prostate-specific antigen, pathologic stage, and Gleason grade). There was a decrease in the rate of surgical margins: odds ratio 0.68/100 patients treated (95% confidence interval [CI] 0.44, 1.05; p=0.08). The predicted probability for a positive surgical margin falls from 17.3% for the first patient to 7.5% for the 301st. These values are close to the observed rates for the first and last 50 patients. There was no important change in surgical risk over the course of the study, and the rate of nerve sparing remained stable throughout the study period. CONCLUSIONS: In this contemporary series, which is unaffected by downward stage migration, the decreasing rate of positive surgical margins can be explained by subtle surgical technique modifications and a continuous multidepartmental effort for quality improvement.

Biopsy↗
PubMed2005

Positive surgical margins and accessory pudendal artery preservation during laparoscopic radical prostatectomy.

PURPOSE: To determine whether preservation of accessory pudendal arteries (APAs) adversely influences the rate of positive surgical margins (PSMs) during laparoscopic radical prostatectomy (LRP). MATERIAL AND METHODS: Between January 2003 and January 2005, 377 men with clinically localized prostate cancer underwent a LRP; 325 met inclusion criteria for this study. The variety (apical or lateral), laterality (left or right), size, and preservation status of all identified APAs were prospectively recorded. A genitourinary pathologist mapped the specimens and established tumor locations and PSM sites. RESULTS: Ninety-six of 325 men (30%) were found to have 125 separate APAs. The apical variety predominated; 56% of APAs were apical and 44% were lateral. Successful preservation was possible for 104/125 (83%) individual arteries. The overall rate of PSM was 11.7%. The rates for those with and without identified APAs were 9% and 13%, respectively (p=0.4). The incidence of PSMs in the ipsilateral region of APA localization was not affected by preservation status; ipsilateral PSM rates were 3% and 6% for those preserved and not preserved, respectively (p=0.5). CONCLUSIONS: Identification and preservation of APAs during laparoscopic radical prostatectomy did not adversely affect the rates of PSMs. APA preservation can be undertaken without compromise to the oncological integrity of the laparoscopic radical prostatectomy.

Arteries↗
PubMed2005

Quality improvement in laparoscopic radical prostatectomy for pT2 prostate cancer: impact of video documentation review on positive surgical margin.

PURPOSE: We correlated intraoperative video documentation and pathology findings to understand the mechanisms by which positive surgical margins occur and improve the surgical technique. MATERIALS AND METHODS: Between January 2003 and May 2004, 240 consecutive patients underwent laparoscopic radical prostatectomy, of whom 180 had pT2 prostate cancer and represent the population of this study. After the first 90 patients (group 1) we started a quality assurance study, analyzing intraoperative video recordings and correlating them with pathology findings in patients with a positive margin. The cancer characteristics and positive margin rate were compared between the first 90 patients and the subsequent 90 after the study was initiated (group 2). RESULTS: Of the 12 cases of positive surgical margins studied the video review helped identify 8 with a technical error. In all 4 cases in which a technical error could not be identified the positive margin site was at the distal apex. The most frequent identifiable mechanism by which positive margins occurred was a capsular tear during neurovascular bundle dissection. The 2 groups were comparable in regard to preoperative cancer characteristics and total tumor volume. In patients who underwent bilateral nerve sparing the positive margin rate was 10.6% in group 1 and 5.4% in group 2 (p = 0.18). All positive margins in group 2 involved the prostatic apex. CONCLUSIONS: Quality assurance efforts through pathological and intraoperative documentation review can help decrease the positive margin rate, particularly in organ confined disease. However, eradicating positive margins at the distal prostatic apex remains a challenge.

Humans↗
PubMed2004

Advances in laparoscopic partial nephrectomy.

PURPOSE OF REVIEW: The advantages of the laparoscopic approach in the management of kidney tumors are unequivocal and the role of laparoscopy in nephron-sparing surgery is evolving. In a selected group of patients with small exophytic renal tumors laparoscopic partial nephrectomy became an alternative to open partial nephrectomy. However, the application of laparoscopic partial nephrectomy to larger, centrally located tumors or tumors in unfavorable sites is limited by the difficulty of achieving adequate, prompt collecting system closure and hemostasis with a limited warm ischemia time. The most recent developments in laparoscopic partial nephrectomy are the subject of this review. RECENT FINDINGS: A number of sealant products have been used as an adjunct or principal hemostatic agent in the animal model. Their application in the clinical setting remains limited to small parenchymal bleeding; larger vessels and pelvicaliceal openings are better managed by vascular clamping and intracorporeal suturing. Vascular clamping confers warm ischemia, and attempts at renal hypothermia included cold kidney irrigation through either a ureteral stent or a renal artery cannulation, and the application of ice slush for parenchymal surface cooling. SUMMARY: Laparoscopic partial nephrectomy is technically demanding; efforts directed towards facilitating hemostasis, improving renal cooling or shortening the warm ischemia time will expand its indications further.

Humans↗
PubMed2003

Acute respiratory distress syndrome.

Acute respiratory distress syndrome is a manifestation of acute injury to the lung, commonly resulting from sepsis, trauma, and severe pulmonary infections. Clinically, it is characterized by dyspnea, profound hypoxemia, decreased lung compliance, and diffuse bilateral infiltrates on chest radiography. Provision of supplemental oxygen, lung rest, and supportive care are the fundamentals of therapy. The management of acute respiratory distress syndrome frequently requires endotracheal intubation and mechanical ventilation. A low tidal volume and low plateau pressure ventilator strategy is recommended to avoid ventilator-induced injury. Timely correction of the inciting clinical condition is essential for preventing further injury. Various medications directed at key stages of the pathophysiology have not been as clinically efficacious as the preceding experimental trials indicated. Complications such as pneumothorax, effusions, and focal pneumonia should be identified and promptly treated. In refractory cases, advanced ventilator and novel techniques should be considered, preferably in the setting of clinical trials. During the past decade, mortality has declined from more than 50 percent to about 32 to 45 percent. Death usually results from multisystem organ failure rather than respiratory failure alone.

Humans↗