PubMed Health⌕ Search

Biomedical subjects

R Yiou

Publications and source records attributed to R Yiou.

14 recordsLinked to original sources
PubMed2006

Long-term functional and oncological results after retroperitoneal laparoscopic prostatectomy according to a prospective evaluation of 550 patients.

The objective of the study was to evaluate the long-term results of retroperitoneal laparoscopic radical prostatectomy (LRP). From 2001 to 2005, 550 consecutive patients underwent a laparoscopic extraperitoneal prostatectomy in our department. Continence and erectile function were analysed prospectively by a self-administrated questionnaire. Mean operating time was 188 min, mean bladder catheterisation time 5.9 days, mean hospital stay 4.6 days Pathological stage was pT2 in 55.8%, pT3a in 29.6%, pT3b in 9.1% and pT4a in 5.4% tumours. Positive surgical margins were 17.9% for pT2, 44.8% for pT3 tumours and 71.4% for pT4a tumours. Five years survival without biochemical progression was 78.8%. After 24 months of follow-up, diurnal continence rate was 91%, and potency rate was 64% when both neurovascular bundles were preserved, 78.6% when the patients were younger than 60 years. LRP is now a standardised procedure. An extraperitoneal approach combines the advantages of a laparoscopic procedure with those of an extraperitoneal approach.

Erectile Dysfunction↗
PubMed2004

[Tissue engineering in urology].

Tissue engineering refers to the techniques that are aimed at regeneration of human tissues and organs. Two elements are necessary for these techniques: matrix and cells. Matrix is the scaffold where tissues may organise. Cells are either autologous cells stimulated to regenerate in vivo, aided by implantation of matrix ("guided tissue regeneration"), or autologous cells cultured outside the body (in vitro) and later returned as auto-transplants. All types of conventional tissue reconstructive surgery need tissue engineering. These techniques have been introduced recently into the clinical practice. One of the main limitations of reconstructive surgery in genitourinary tract is the lack of autologous tissue. Two autotransplants could be distinguished: coherent tissue structure or cell suspensions. The great number of studies published in this area emphasizes the importance of the future clinical implication in urology.

Animals↗
PubMed2004

Laparoscopic promontory sacral colpopexy: is the posterior, recto-vaginal, mesh mandatory?

OBJECTIVE(S): The aim of our retrospective study was to determine if systematic placement of a posterior mesh, in addition to an anterior vesico-vaginal mesh, is necessary for laparoscopic treatment of pelvic organ prolapse. METHODS: A laparoscopic promontory sacral colpopexy was performed in 108 patients, including 55 patients with a concurrent laparoscopic Burch procedure (50.9%). We compared 33 patients treated with a single anterior mesh (SAM) and 71 treated with a double, anterior and posterior, mesh (DM). RESULTS: The difference between the SAM and DM groups was statistically significant in terms of posterior compartment failure (rectocele and/or enterocele): 31.3% and 5.9%, respectively (p=0.0006). This significant difference persisted in the Burch (B) group (p=0.001), but not in the non-Burch (NB) group (p=0.98). Among the SAM group, this difference between the B and NB groups, was significant (57.1% versus 0%; p=0.0015) and above all not a single posterior failure was observed in the NB group. CONCLUSION(S): The placement of a posterior mesh, if highly effective, appeared unnecessary in the absence of an associated Burch procedure or a patent posterior prolapse. The posterior mesh also increased risk of postoperative complications and side effects.

Adult↗
PubMed2004

Laparoscopic radical nephrectomy for T1 renal cancer: the gold standard? A comparison of laparoscopic vs open nephrectomy.

OBJECTIVE: To evaluate the complication rate and clinical follow-up of patients treated for T1 renal cancer by open or laparoscopic nephrectomy at the same institution, as this approach appears to be attractive for treating small renal cancers. PATIENTS AND METHODS: Between 1995 and 2002, 39 patients underwent retroperitoneal laparoscopic and 26 transperitoneal open radical nephrectomy for T1 renal cancer (TNM 1997). Variables before during and after surgery, e.g. cancer recurrence, were compared between the groups. RESULTS: There were no differences between the laparoscopic and open groups in age, sex ratio, weight, height, fitness score, operative duration (134 vs 133 min), minor or major complications, tumour diameter, Fuhrman grade or length of follow-up. Patients who underwent laparoscopic surgery had less blood loss (133 vs 357 mL, P < 0.001), less need for transfusion (none vs 150 mL, P = 0.04), a lower consumption of analgesia drugs, and shorter hospitalization (5.5 vs 8.8 days, P < 0.001). With a mean follow-up of 20.4 months there was no recurrence or tumour progression. CONCLUSION: Laparoscopic radical nephrectomy for patients with T1 renal cancer is a safe, reliable procedure that decreases hospitalization time and bleeding, and ensures the same cancer control as open nephrectomy.

Adult↗
PubMed2002

Outcome of radical cystectomy for bladder cancer according to the disease type at presentation.

OBJECTIVE: To examine whether the outcome of cystectomy for invasive transitional cell carcinoma (TCC) of the bladder was influenced by the type of disease at initial presentation. PATIENTS AND METHODS: The charts of 76 patients treated for TCC by radical cystectomy from 1987 to 1997 in our unit were reviewed. The patients were divided into three groups: group 1 comprised 43 patients with primary invasive disease; group 2 included 12 patients with progression of an initial superficial bladder tumour after failure of conservative treatment; and group 3 comprised 21 patients who had a radical cystectomy for superficial TCC, with a high risk of progression after attempts at conservative treatment. The pathological findings on transurethral resection and cystectomy specimens, cancer-specific survival and the time to progression were compared among the three groups. RESULTS: The rate of pT0 in cystectomy specimens was 16%, 41% and 24% in groups 1, 2 and 3, respectively. Under-staging occurred in 24% of cases in group 3. The 10-year cancer-specific survival rates were 48%, 47% and 82% in groups 1, 2 and 3, respectively. The cancer-specific survival rate and progression rate were not significantly different between groups 1 and 2, but were significantly lower/higher in these patients than in group 3 (P < 0.01). CONCLUSIONS: These data suggest that the prognosis of superficial TCC which progresses despite conservative management is no better than that of invasive TCC at initial presentation, despite the closer follow-up received by the former patients. Early identification of this group of patients may improve the cancer-specific survival, as early cystectomy for high-risk superficial TCC yields better results.

Aged↗
PubMed2002

Muscle precursor cell autografting in a murine model of urethral sphincter injury.

OBJECTIVE: To determine whether muscle precursor cells (MPCs) harvested from limb skeletal muscle can enhance the regeneration process of the striated urethral sphincter after injury. MATERIAL AND METHODS: Striated urethral sphincters of male mice were injured by an injection of a myotoxic substance (notexin). In the experimental group, 2 days after injury, MPCs were enzymatically harvested from striated muscles of the lower limbs and labelled with PKH 26, then immediately re-injected into the injured urethral sphincter of the same animal. In the control group, saline buffer was injected instead of MPCs. Animals were killed 7 days or 1 month after injury and the sphincters removed for histological study (the presence of PKH 26-labelled myofibres, measurement of myofibre diameter and total number of myofibres). RESULTS: MPC autografting accelerated sphincter muscle repair, as shown by a higher myofibre diameter (P = 0.03) and number (P = 0.01) in the experimental group than in the controls at 7 days. One month after their injection MPCs were still detectable in the regenerating sphincters and participated in the formation of new myofibres. CONCLUSION: This study provides the experimental basis for a new therapeutic approach to urethral sphincter insufficiency after surgical or obstetrical injury, based on MPC autografting.

Animals↗
PubMed2001

Anatomical basis of lumboscopy.

Lumboscopy provides an approach to the retroperitoneum for the majority of upper urinary tract operations. The technique involves a knowledge of specific anatomical landmarks that differ from those in classical open surgery, because of the inferior approach to the renal pedicle with the kidney initially mobilized in a ventral and cranial position. An anatomical study was conducted on five cadavers, using images from surgical operations, in order to describe the vascular elements of the retroperitoneal spaces as they are approached during lumboscopy, as well as to define specific anatomical landmarks. Identification of psoas major is crucial as it is then possible to locate the renal pedicle opposite and the area of the great vessels medially. During dissection of the renal pedicle the renal vein and its branches are the first elements to be approached. On the left side the distal portion of the renal vein can be confused with a reno-hemi-azygo-lumbar trunk, due to the initial ventral mobilization of the kidney stretching it. Because of the inferior view of the renal pedicle the reno-hemi-azygo-lumbar trunk can obscure part of the renal artery and may be confused with the renal vein. On the right side initial identification of the inferior vena cava on the medial aspect of psoas major facilitates identification of the gonadal, renal and suprarenal veins all located in the same plane.

Cadaver↗
PubMed2001

Relationship between penile thermal sensory threshold measurement and electrophysiologic tests to assess neurogenic impotence.

OBJECTIVES: Erectile function is usually assessed by neurophysiologic tests such as the bulbocavernosus reflex or pudendal nerve somatosensory evoked potentials. These tests investigate only large nerve fibers, although erection depends on autonomic nerve fibers, which are of small diameter. Warm and cold sensory fibers have similar calibers as the autonomic nerve fibers, and their integrity can be reliably evaluated by the measurement of thermal sensory thresholds. We studied penile thermal sensory testing in parallel with standard electrophysiologic tests to assess their sensitivity in the diagnosis of penile neuropathy. METHODS: Twenty-five normal male subjects without erectile dysfunction or evidence of diffuse neuropathy (group 1) and 35 diabetic patients who complained of impotence (group 2) were studied. Erectile function was quantitated using the erectile dysfunction symptom score. Warm, cold, and vibratory sensory thresholds were assessed on the dorsal aspect of the penis. In addition, penile sympathetic skin responses and pudendal nerve somatosensory evoked potentials were recorded. RESULTS: We found a significant difference between the two groups in the erectile dysfunction symptom score (P <0.0001), cold threshold (P = 0.0007), and warm threshold (P = 0.0025), but not for the other parameters. The erectile dysfunction symptom score correlated with the penile warm and cold thresholds (P = 0.0006 and 0.002, respectively). CONCLUSIONS: Thermal thresholds assess small nerve fiber damage, which can indirectly reflect autonomic disturbances, particularly in the context of a diffuse neuropathy such as diabetic polyneuropathy. Penile thermal sensory testing correlated strongly with the clinical evaluation of erectile function and is a new and promising tool for the diagnosis of neurogenic impotence.

Adult↗
PubMed2001

Pudendal nerve terminal motor latency: age effects and technical considerations.

OBJECTIVES: The measurement of the pudendal nerve terminal motor latency (PNTML) is used to assess anal sphincter innervation. In healthy subjects, we studied the influence of age on PNTML and the advantage of a new intra-rectal stimulator. METHODS: PNTML was determined in a first series of 40 normal subjects, aged 21-75 years, using a standard St. Mark's electrode, and in a second series of 20 normal subjects over 50 years, using a new intra-rectal monopolar stimulator that did not require finger insertion through the anal canal. RESULTS: In the first series, PNTML ranged from 1.8 to 5.6 ms (mean+/-SD 2.94+/-0.8 ms) and correlated positively with the age of the subjects (P=0.01, Spearman test). In the second series, PNTML ranged from 2.2 to 5.4 ms (3.7+/-0.9 ms) and was similar to that of the subjects over 50 years of the first series (3.5+/-0.4 ms) (P=0.35, Mann-Whitney U test). CONCLUSIONS: This study showed significant effects of age on PNTML. This should encourage every examiner to establish age-stratified reference values of PNTML for older age groups. In addition, we showed the advantage of using a new type of intra-rectal stimulator to reduce the patient's discomfort by avoiding finger insertion to stimulate the pudendal nerve.

Adult↗
PubMed2001

The pathophysiology of pelvic floor disorders: evidence from a histomorphologic study of the perineum and a mouse model of rectal prolapse.

The muscle changes related to pelvic floor disorders are poorly understood. We conducted an anatomical and histological study of the perineum of the normal mouse and of a transgenic mouse strain deficient in urokinase-type plasminogen activator (uPA-/-) that was previously reported to develop a high incidence of rectal prolapse. We could clearly identify the iliococcygeus (ILC) and pubococcygeus (PC) muscles and anal (SPA) and urethral (SPU) sphincters in male and female mice. The bulbocavernosus (BC), ischiocavernosus (ISC) and levator ani (LA) muscles could be found only in male mice. Histochemical analysis of the pelvic floor muscles revealed a majority of type IIA fibres. Rectal prolapses were observed only in male uPA-/- mice. The most obvious finding was an irreducible evagination of the rectal mucosa and a swelling of the entire perineal region corresponding to an irreducible hernia of the seminal vesicles through the pelvic outlet. The hernia caused stretching and thinning of the ISC, BC and LA. Myopathic damage, with degenerated and centronucleated myofibres, were observed in these muscles. The PC, ILC, SPA and SPU were not affected. This study provides an original description of a model of pelvic floor disorder and illustrates the differences existing between the perineum of humans and that of a quadruped species. In spite of these differences, the histopathologic changes observed in the pelvic floor muscles of uPA-/- mice with rectal prolapse suggest that prolonged muscular stretching causes a primary myopathic injury. This should be taken into account in the evaluation of pelvic floor disorders.

Animals↗
PubMed2000

Assessment of penile small nerve fiber damage after transurethral resection of the prostate by measurement of penile thermal sensation.

PURPOSE: To determine the occurrence of penile small nerve fiber damage following transurethral resection of the prostate (TURP) for benign prostatic hypertrophy (BPH). MATERIALS AND METHODS: Penile nerve function was evaluated in 18 consecutive patients prior to and one month after TURP for BPH. To test nerve fibers of small diameter, the penile warm and cold sensory thresholds were measured by means of a Peltier-based device, as well as the penile sympathetic skin potentials obtained following electrical stimulation at the wrist. To test nerve fibers of large diameter, the pudendal nerve somatosensory evoked potentials (pSEPs) and the penile vibratory thresholds were recorded. Clinical erectile function was quantified using a standardized questionnaire (erectile dysfunction symptom score, EDSS). Urinary handicap was assessed by the measurement of maximum flow rate (MFR) at uroflowmetry and by a standardized questionnaire (AUA symptom score, AUASS). RESULTS: Penile warm threshold (+7.8 vs +6.3C, p = 0.005), cold threshold (-8.5 vs -5.7C, p = 0.003) and vibratory threshold (9.3 vs 7.9 microm., p = 0.03) were significantly higher after than prior to TURP. The amplitude of pSEPs tended to decrease (1.7 versus 2.3 microV, p = 0.06), whereas the remaining neurophysiological parameters were unchanged. Clinical assessment by EDSS demonstrated a significant postoperative erectile function impairment (20.2 vs 17.5, p = 0.04), whereas mictional function improved (MFR: 19 vs 8.8 ml./s and AUASS: 4.9 versus 15.1, p < 0.0001). CONCLUSIONS: This study highlights the occurrence of penile small nerve fiber damage following TURP and supports the hypothesis of neurogenic damage as the primary cause of post-operative erectile dysfunction.

Aged↗
PubMed1999

Perineal approach to radical prostatectomy in kidney transplant recipients with localized prostate cancer.

Close urologic follow-up of renal transplant candidates and recipients often reveals prostate carcinoma at an early stage. Two patients who underwent renal transplantation for end-stage disease also underwent radical perineal prostatectomy for localized prostate carcinoma, 3 years after grafting in 1 patient and 4 years before grafting in the other. The perineal approach to prostatectomy may facilitate later renal transplantation and avoid allograft damage.

Adenocarcinoma↗