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J L Pariente

Publications and source records attributed to J L Pariente.

32 records · Page 2Linked to original sources
PubMed1998

Characterization of urinary calculi: in vitro study of "twinkling artifact" revealed by color-flow sonography.

OBJECTIVE: The "twinkling artifact" is a color-flow sonographic artifact described behind calcifications and presenting as a random color encoding in the region where shadowing would be expected on gray-scale images. Our purpose was to study the relationship between this twinkling artifact seen behind urinary stones on color-flow sonography and the morphology or biochemical composition of these urinary stones. MATERIALS AND METHODS: Forty-seven urinary stones were studied in vitro with color-flow sonography. Transmit frequency, color gain, velocity range, color filters, focal depth, and depth of field were changed during scanning. The twinkling artifact was graded 0 when absent, 1 when present but occupying a portion of acoustic shadowing, and 2 when occupying the entire acoustic shadowing. Stones were studied under a binocular magnifying glass to characterize the surface, and infrared spectrophotometry was used to determine the chemical composition. RESULTS: Calculi of calcium oxalate dihydrate and calcium phosphate always produced a grade 1 or grade 2 twinkling artifact. Absence of artifact was noted only for calcium oxalate monohydrate and urate stones. In 100% of grade 0 calcium oxalate stones, the monohydrate compound was predominant (>93%). In 100% of grade 2 calcium oxalate stones, the dihydrate compound was predominant (>75%). For calcium oxalate stones, the surface pattern was correlated with their composition. Sensitivity and specificity for absence of artifact, as indicative of calcium oxalate monohydrate, were 60% and 83%, respectively, for all stones and 56% and 100%, respectively, only for radiopaque stones. CONCLUSION: An in vitro relationship exists between the twinkling artifact and the morphology of urinary stones. Color-flow sonography could play a role in detecting dense calcium oxalate monohydrate calculi, which in turn may help predict fragmentability.

Artifacts↗
PubMed1998

[Can the prostatic capsule be preserved during cystectomy for bladder tumors: a study of urethral and prostatic involvement in the cystectomy specimens].

OBJECTIVES: To evaluate the frequency of urethral and prostatic lesions on cystectomy specimens for bladder tumour. MATERIAL AND METHODS: This retrospective histological study was based on 260 specimens: radical cystectomies performed in 7 operative sites. The prostate and urethra were analysed in 3 planes (upper, middle and lower thirds). The apex was studied separately. Urethral invasion was identified by continuity of the tumour or by the presence of vesical CIS. RESULTS: Urethral involvement is frequent (30.6% cases) essentially due to contiguous invasion (43/80). CIS is the second pathological association (44 urethral CIS/75 bladder CIS). Prostatic adenocarcinoma was present in 17.8% of cases with a Gleason score > 6 for 30% of lesions. CONCLUSION: The high frequency of urethral and prostatic involvement does not justify preservation of the prostate during cystectomy. A serial prospective study should define the precise criteria able to minimize the risk of conservative surgery.

Adenocarcinoma↗
PubMed1998

[The biocompatibility of catheters and stents used in urology].

Biocompatibility can be interpreted as the optimal combination of a series of interactions occurring at the material-tissue interface as soon as these two systems are in contact. It is a multifactorial interface property which integrates all of the phenomena involved in a biological environment i.e. absence of toxicity of the material for the body and absence of degradation of the material by the body. Biocompatibility can be evaluated in a normative context by using in vivo techniques in animals or in vitro techniques using cell cultures allowing the study of cytotoxicity (related to a concept of safety) and cytocompatibility (related to biological acceptability) of a material. Because of their intimate contact with the urothelium throughout implantation, the biocompatibility of catheters and stents constitutes a major requirement. This review presents the current data reported in the literature concerning the evaluation of the biocompatibility of materials used in urology. The main problems encountered are alterations of the urothelium, such as erosions or, on the contrary, mucosal hyperplasia, and the existence of incrustations developing on these materials.

Animals↗
PubMed1997

Initial evaluation of CYFRA 21-1 diagnostic performances as a urinary marker in bladder transitional cell carcinoma.

PURPOSE: CYFRA 21-1, an immunoradiometric assay developed for the detection of a soluble cytokeratin 19 fragment, is evaluated for its diagnostic performance in urine of patients with transitional cell carcinoma. MATERIALS AND METHODS: CYFRA 21-1 was investigated in serum and urine of 128 patients, including 48 with bladder transitional cell carcinoma (group 1), 44 with other urological pathological conditions (group 2) and 36 free of urothelial disease (group 3). Urinary cytopathology was also performed. RESULTS: Mean urinary CYFRA was 123.5 +/- 53, 11.9 +/- 4.8 and 2.3 +/- 0.2 ng./ml. for groups 1 to 3, respectively, and was significantly different. From the receiver operating characteristics curve, the optimal combination of 96% sensitivity and 74% specificity was determined for a threshold value of 4 ng./ml. while overall cytopathology sensitivity was 43%. CONCLUSIONS: Urinary CYFRA 21-1 may be a useful marker for diagnosing transitional cell carcinoma.

Aged↗
PubMed1997

[The value of transrectal MRI in the staging of localized prostate cancer].

OBJECTIVE: To determine the diagnostic value of transrectal magnetic resonance imaging (MRI) in the local staging of prostatic cancer. METHOD: 75 patients suffering from clinically localized prostatic cancer were included consecutively from December 1992 to September 1996. An MRI examination (1.5 Tesla, Siemens) with a transrectal coil was performed before radical prostatectomy. The results of this examination in terms of capsular invasion, seminal vesicle lesion and apical invasion were correlated with the results of histological examination of the operative specimen and the findings of digital rectal examination, transrectal ultrasonography, serum PSA level and biopsy mapping. RESULTS: The best performance of transrectal MRI concerned elimination of seminal vesicle lesion with a specificity of 92%. The positive predictive value of transrectal MRI was 90% for the capsular invasion. The positive predictive value of transrectal MRI was 56% for the apex, the sensitivity was 40% and the specificity was 82%. When transrectal MRI did not reveal any extraprostatic involvement the risk of positive margins on radical prostatectomy was less than 6%. CONCLUSION: In this study, transrectal MRI appeared to be satisfactory to improve the staging of localized prostate cancer, especially in terms of seminal vesicle lesion and apical invasion, but, most importantly, appeared to be very useful to predict negative resection margins.

Aged↗
PubMed1996

[Therapeutic strategy apropos of 122 cases of early disclosed traumatic rupture of the urethra].

When ureteral rupture is suspected after trauma with fracture of the pelvis, insertion of a suprapubic catheter is required as an emergency measure. Ureteral lesions must be repaired early by the 5th to 10th day after trauma. Pyelography or retrograde ureterography is required to determine whether there is total or partial rupture and the degree of damage is identified endoscopically. We operated 73 total ruptures in deferred emergency situations (58 transpubic, 14 perineal approaches) and achieved good results in 80%. There were also 41 partial ruptures treated with an indwelling catheter in which 21 developed strictures requiring secondary uretrotomy. In three particular situations (anorectal damage, infected perineal wound, polytrauma with head trauma), in 8 patients were managed with suprapubic drainage alone before repair 3 months later. Different complications, including stricture and impotency were observed.

Adolescent↗
PubMed1995

[Conservative surgery in cancer of the kidney].

Partial nephrectomy is classically indicated in patients with renal cell cancer on a single kidney, although a certain amount of debate continues on surgical technique: simple enucleation or true partial nephrectomy. Incidence of multifocal tumours has been estimated at 6 to 19.6%. The crucial problem for the surgeon is to recognize satellite tumours pre- and peroperatively since it has been estimated that 4 to 10% of renal cell carcinomas contain a multifocal disease unrecognized during surgery. Is conservative nephrectomy acceptable for patients with a functional contralateral kidney? There are several arguments in favour of the technique: fortuitously discovered tumours are generally smaller and in a less advanced stage, morbidity after conservative surgery is low compared with total nephrectomy, nephron sparing improves long-term renal function and survival at 3 to 5 years is 95 to 100%. The fact that the risk of cancer on the contralateral kidney is small (1 to 2%) compared with the risk of local recurrence and the lack of sufficiently long follow-up in large series are negative arguments. Conservative nephrectomy must therefore be considered as the best solution when nephron sparing is essential. Total nephrectomy remains the reference treatment in other cases although the discussion remains open for cases with small (< 2.5 cm) tumours.

Carcinoma, Renal Cell↗
PubMed1992

[Placenta praevia percreta with bladder invasion: a case report].

The authors report a rare case of placenta praevia percreta with bladder invasion giving rise to the need to carry out an emergency hysterectomy in order to stop the bleeding. The literature when analysed showed the possible outcome of this complication in a woman who had already had a caesarean section and who had placenta praevia that required a second caesarean. In this situation it is almost inevitable that a hysterectomy has to be carried out to stop the bleeding. The hysterectomy should be a total hysterectomy but this can be difficult because of the invariable "fusion" that takes place between the uterus and the posterior wall of the bladder. What has to the done bladder can range from simple closure of a hole in the bladder to ureteric diversion with reimplantation of the ureter depending on how badly the bladder has been invaded. In our case after a sub-total hysterectomy had been carried out with simple closure of the bladder, it was necessary to re-operate to treat a fistula between the bladder and the cervix.

Adult↗
PubMed1991

[Functional and metabolic results of 24 Bordeaux-type bladder replacements following total prostato-cystectomy with a more than 2 years follow-up].

In March 1985, we realised the first Bordeaux neo-bladder, with detubularized ileo-colic segment (15 cm of ascending colon and 20 to 25 cm of ileum). The urethra is anastomosed at the lowest point of the caecum. 61 male patients underwent total replacement of the bladder, and we analyse the results in 24 of them, with a follow up more than 2 years. The following results were noted: the sensation of voiding is always physiological, daytime continence is quite perfect, while nighttime continence is good for 71% of patients, the filling pressure of the neobladder is low with a maximum of 20 cm H 0 (range 5-20 cm H20), and its capacity ranged from 300 ml to 400 ml, the mean flow rate is 21 ml/s. We encountered no complication, nothing but 2 gall-stones and two patients with low vitamin B 12. We didn't note neither diarrhea, nor hyperchloremic acidosis. All patients maintained normal renal function. Initially, the indication of Bordeaux ileo-colic neobladder was limited to bladder replacement after cysto-prostatectomy for bladder cancer. Now, the good results obtained, and their durability without any major complication allow us to extend our indications to bladder enlargements in neurogenic bladders.

Cystectomy↗
PubMedDate not supplied

[Long-term results of a series of 39 of Bordeaux-type bladder replacements using ileocecal grafts after total prostatectomy and cystectomy].

A series of 136 bladder replacements using colon tissue was performed after total prostacystectomy for cancer of the bladder. Sixty-four Bordeaux-type ileocecal replacements were performed. The first bladder Bordeaux-type was created in March 1985. The technique involves detubulization of an ileocecal segment using 15 cm of the right colonic segment submucally according to the Goodwin technique. Uretral anastomosis uses the lower most portion of the cecum. Ileocecal anastomosis is performed manually or using a biofragmenting ring with terminoterminal junction as in the last 12 patients. After a follow-up of 1 to 8 years, 39 patients were evaluated for long-term results. The notion of need was obvious. Daytime continence was achieved in all patients. Night-time continence was achieved in 75% including several patients who had nocturnal mictions. Bladder filling occurred at low pressure with peaks from 5 to 20 cm H2O. Bladder capacity varied from 300 to 400 cc. Mean urinary flow was 21 ml/s. No cases of diarrhea were observed. Radiotransparent and asymptomatic bladder stones were seen in two cases. Mean corpuscular volume, vitamin B12 and folic acid levels were normal in 3/4 patients. No cases of elevated chloride were observed and no cases of oxaliuria occurred. Bladder Bordeaux-type construction offers a functional volume similar to the normal bladder with good metabolic tolerance, remarkable good stability over time and no deterioration of the upper urinary system.

Cecum↗