Biomedical subjects

Olivier Traxer

Publications and source records attributed to Olivier Traxer.

At least 19 recordsLinked to original sources

PubMed2006

Upper urinary tract transitional cell carcinoma: recurrence rate after percutaneous endoscopic resection.

OBJECTIVES: To assess oncologic outcomes in patients undergoing percutaneous management for upper urinary tract transitional cell carcinoma (UUT-TCC) of the renal cavities. METHODS: We performed a retrospective review of data for patients who underwent percutaneous conservative surgery for a UUT-TCC between 1989 and 2005: sex; age at diagnosis; mode of diagnosis; smoking; history of bladder cancer; type of surgery; complications; tumour site, size, stage and grade, and recurrence and progression. We evaluated recurrence and survival rates. RESULTS: Data were analyzed for 24 patients. Median age was 70 yr. The tumour was located in the renal pelvis in 11 patients and in the caliceal system in 13 patients. Mean tumour size was 1.8 cm (range: 0.8-2.9). Four patients had a history of bladder carcinoma. Three patients experienced perioperative blood loss requiring transfusion, and one experienced colon wound. Median follow-up was 62 mo. Eight (33.3%) patients experienced local recurrence (three in the treated urinary tract, one in the contralateral tract, four in the bladder). Five patients underwent nephroureterectomy (NUT) during follow-up. Five (20.8%) patients have died, four from disease progression and one from cardiovascular causes. The 5-year disease-specific and tumour-free survival rates were 79.5% and 68%, respectively. CONCLUSIONS: Percutaneous management can be recommended as an alternative to NUT or ureteroscopy for low-grade or superficial UUT-TCCs localised in the renal cavities. These patients require long-term postsurgical surveillance. For patients with high-grade or invasive tumours, open NUT remains the gold standard.

Aged↗

PubMed2006

Type 2 diabetes increases the risk for uric acid stones.

An increased prevalence of nephrolithiasis has been reported in patients with diabetes. Because insulin resistance, characteristic of the metabolic syndrome and type 2 diabetes, results in lower urine pH through impaired kidney ammoniagenesis and because a low urine pH is the main factor of uric acid (UA) stone formation, it was hypothesized that type 2 diabetes should favor the formation of UA stones. Therefore, the distribution of the main stone components was analyzed in a series of 2464 calculi from 272 (11%) patients with type 2 diabetes and 2192 without type 2 diabetes. The proportion of UA stones was 35.7% in patients with type 2 diabetes and 11.3% in patients without type 2 diabetes (P < 0.0001). Reciprocally, the proportion of patients with type 2 diabetes was significantly higher among UA than among calcium stone formers (27.8 versus 6.9%; P < 0.0001). Stepwise regression analysis identified type 2 diabetes as the strongest factor that was independently associated with the risk for UA stones (odds ratio 6.9; 95% confidence interval 5.5 to 8.8). The proper influence of type 2 diabetes was the most apparent in women and in patients in the lowest age and body mass index classes. In conclusion, in view of the strong association between type 2 diabetes and UA stone formation, it is proposed that UA nephrolithiasis may be added to the conditions that potentially are associated with insulin resistance. Accordingly, it is suggested that patients with UA stones, especially if overweight, should be screened for the presence of type 2 diabetes or components of the metabolic syndrome.

Age Factors↗

PubMed2006

Comparison of open nephroureterectomy and ureteroscopic and percutaneous management of upper urinary tract transitional cell carcinoma.

OBJECTIVES: To compare the outcomes in patients who had undergone either open nephroureterectomy or conservative endoscopic surgery (ureteroscopic or percutaneous management) for upper urinary tract transitional cell carcinoma. METHODS: We performed a retrospective review of the data for patients treated surgically for upper urinary tract transitional cell carcinoma from 1990 to 2004. The data included patient sex, age at diagnosis, mode of diagnosis, smoking history, history of bladder cancer, type of surgery, complications, and tumor site, size, stage, grade, recurrence, and progression. We also evaluated the recurrence and survival rates. RESULTS: Data were analyzed for 97 patients. The median patient age was 68 years. Sixteen patients had a history of bladder tumor. The surgical procedure was open nephroureterectomy in 54 patients, ureteroscopy in 27, and percutaneous endoscopic ablation in 16. The tumor stage, grade, and site were independent prognostic factors for survival in a multivariate analysis (P <0.05). The 5-year disease-specific survival rate was 81.9% for low-grade tumors and 47.3% for high-grade tumors (P = 0.0001). A correlation (P = 0.002) was found between low-grade tumors and superficial tumors. In patients with low-grade tumors (n = 46), the 5-year disease-specific survival rate after nephroureterectomy, ureteroscopy, and percutaneous endoscopy was 84%, 80.7%, and 80%, respectively (P = 0.89); the corresponding 5-year tumor-free survival rates were 75.3%, 71.5%, and 72% (P = 0.78). CONCLUSIONS: Conservative surgery can be recommended as an alternative to nephroureterectomy for low-grade or superficial upper urinary tract transitional cell carcinoma. For patients with high-grade or invasive tumors to be candidates for conservative surgery will require the development of additional prognostic factors (eg, molecular markers). These patients require long-term postoperative surveillance.

Aged↗

PubMed2006

New-generation flexible ureterorenoscopes are more durable than previous ones.

OBJECTIVES: To determine the deterioration in the maximal active deflection and flow capabilities of a new-generation flexible ureteroscope (URS). METHODS: We performed 50 ureterorenoscopies using the same URS: a Karl Storz 11278 AU1 Flex-X, which is capable of a 270 degree active deflection in the ventral and dorsal directions. Postoperatively, we evaluated the maximal active ventral and dorsal deflection, irrigation flow at 100 cm H2O, and the number of broken optical fibers. RESULTS: The URS was used for a total of 76 hours, 15 minutes (average 95 minutes per procedure). The maximal ventral deflection had deteriorated from 270 degrees to 208 degrees at the last procedure. The maximal dorsal deflection had decreased from 270 degrees to 133 degrees. The irrigation flow at 100 cm H2O had decreased from 50 mL/min initially to 40 mL/min at the last procedure. The number of broken image fibers had reached six at the 50th procedure. One repair was necessary at the 50th procedure because of a laser perforation of the working channel. CONCLUSIONS: The need for repair occurs less frequently with the new-generation of URSs, especially when they are used by an experienced endourologist. In the future, improvements in the durability of the flexible URS will still be key for widespread use of the technique and especially to limit damage by the laser to the working channel.

Durable Medical Equipment↗

PubMed2006

Endoscopic lithotripsy and the FREDDY laser: initial experience.

BACKGROUND AND PURPOSE: The frequency-doubled double-pulse neodymium:YAG (FREDDY) laser has been developed for endoscopic lithotripsy and combines the characteristics of solid and dye lasers with a thin flexible optical fiber enabling it to be used with flexible ureterorenoscopy. Furthermore, it is less expensive and easier to maintain than other lasers. Our goal was to evaluate its efficacy and role in the ureteroscopic treatment of urinary stones. PATIENTS AND METHODS: We used a FREDDY laser in 26 patients (29 stones). For 4 stone cases, this was the first line of treatment; for the remaining cases, this was the second line of treatment, following SWL in 23 cases and nephrolithotomy in 2 cases. The mean stone size was 9 mm, with a range of 6 to 15 mm. There were 13 renal and 16 ureteral stones. The absence of residual fragments at 3-month postoperative radiography was considered to reflect successful treatment. RESULTS: Twenty-six stones were treated with satisfactory results. Within 3 months, 18 patients were stone free (69%), and 72.4% of the stones (21/29) had been treated completely. Fragments of 8 stones still remained in 8 patients. Of these stones, 5 were >10 mm and persisted at 3 months. Fragmentation was ineffective for 2 cystine stones and poor for 1 calcium oxalate monohydrate stone. Hospitalization, on average, was 1.5 days with a range of 1 to 3 days. A ureteral perforation was observed in the case of an impacted ureteral stone. CONCLUSIONS: Because of the wavelengths used, endoscopic FREDDY laser lithotripsy is an effective and harmless method. This laser can be used as a therapeutic tool because of its moderate cost and ability to be used with flexible ureterorenoscopy. However, it is important to be aware of the FREDDY laser's limited fragmentation capabilities for cystine stones and its inability to treat tissue lesions such as urinary-tract stenosis and tumors.

Adult↗

PubMed2006

[Flexible ureteroscopy and holmium-Yag laser: material and technique].

Flexible ureteroscopy combined with Holmium-YAG laser is an effective, reproducible and minimally traumatic diagnostic and therapeutic technique perfectly adapted to diseases of the upper urinary tract. This technology must be part of the therapeutic armamentarium of any centre involved in the management of urinary stones. The technical facilities must be complete and adapted. Flexible ureteroscopy is a technique with a rapid learning curve once the operator is familiar with all of the equipment. This article describes the material and technique of flexible ureteroscopy combined with Holmium-YAG laser.

Equipment Design↗

PubMed2006

[Inferior calyx stone and flexible ureterorenoscopy to mobilize the stone before fragmentation].

Flexible ureterorenoscopy is recommended for the treatment of inferior calyx stones, 10 to 15 mm in diameter, particularly after failure of extracorporeal lithotripsy. It is recommended to mobilize an inferior calyx stone towards the renal pelvis or superior calyx before starting fragmentation. This manoeuvre is essential to preserve the ureterorenoscope. The objective of this technical note is to explain the stone "relocalization" manoeuvre and describe how in situ treatment of an inferior calyx stone can be dangerous for the flexible ureterorenoscope.

Humans↗

PubMed2006

[Multiple endocrine neoplasia type 1: a possible cause of severe and recurrent urolithiasis].

Multiple endocrine neoplasia (MEN) is defined by the presence of at least two functionally unrelated endocrine gland tumours in the same subject. There are three types of MEN. MEN type 1 (or Wermer syndrome) is an autosomal dominant cancer syndrome. In the light of a case report, the authors recall the characteristics of MEN type 1 responsible for severe and recurrent urolithiasis and emphasize the need for systematic aetiological work-up for all patients presenting a first episode of urolithiasis according to the guidelines of the Association Française d'Urologie Stone Committee (CLAFU).

Female↗

PubMed2006

[Metabolic syndrome, obesity and urolithiasis].

The current concept of metabolic syndrome comprises abdominal obesity and cardiovascular risk factors (HT and metabolic disorders). Compared to a control group, individuals with metabolic syndrome have a fourfold higher risk of cardiovascular disease and an increased risk of diabetes. Apart from cardiovascular morbidity, these patients also appear to have an increased incidence of urolithiasis. Urologists must therefore recognize this syndrome in order to identify this particular subgroup of urolithiasis patients. The objective of this article is to review the metabolic syndrome in order to help urologists to recognize this syndrome so that they can identify patients requiring more specific management and medical follow-up.

Humans↗

PubMed2006

[Study of the safety of double J ureteric stents].

INTRODUCTION: Endoscopic placement of ureteric stents was first described in 1967 by Zimskind. Few studies have evaluated the impact of double J ureteric stents on the patient's quality of life. This prospective study was designed to evaluate the safety and morbidity associated with ureteric stents. PATIENTS AND METHODS: From February 2001 to June 2003, 115 patients (64 men and 51 women; mean age: 49.5 years [range: 19-90]) were included in this study. Ureteric stents were placed under general anaesthesia for urolithiasis (80 cases), ureteroplasty (25 cases) and extrinsic ureteric compression (10 cases). 28 cm 7F polyurethane stents were used in every case. Patients with double J stent for renal transplantation or pregnancy were excluded. The safety of stents was evaluated on the day of removal by a questionnaire based on a 100 mm visual analogue scale (VAS). RESULTS: The mean duration of stenting was 91.8 days (range: 10-287). Macroscopic haematuria was reported in 56% of cases, dysuria was reported in 36% of cases and urgency was reported in 78% of cases. The mean score on the VAS was 44 (0-100) for global impression, 41 (0-100) for bladder pain, 41 (0100) for low back pain, 62 (2-100) for low back pain during micturition and 32 (0-100) for straining on the stent. CONCLUSIONS: Double J stents are associated with high morbidity, which is sometimes underestimated by operators. Our study confirms that the duration of stenting must be as short as possible in order to improve patient comfort, which implies rapid organization of the aetiological management of these patients.

Adult↗

PubMed2006

[Anterograde flexible ureteroscopy for stones of the uretero-sigmoid junction of a Mainz II pouch].

The incidence of stones after urinary diversion is variable but considerable. The authors report the case of a patient with a stone of the uretero-sigmoid junction of a Mainz II pouch occurring three years after radical cystectomy for recurrent carcinoma in situ refractory to conservative treatment. The patient was treated by anterograde Holmium:YAG laser flexible ureteroscopy. This clinical case illustrates the role of anterograde flexible ureteroscopy combined with Holmium:YAG laser as a minimally invasive, sale and effective technique for the management of stones in a urinary diversion.

Colon, Sigmoid↗

PubMed2006

[Role of endoscopy in the management of upper urinary tract tumors].

Transitional cell carcinomas of the upper urinary tract are rare tumours that represent about 5% of all transitional cell carcinomas. The reference treatment is currently open nephroureterectomy. Low-grade or superficial urinary tract tumours have a good prognosis, similar to that of noninvasive bladder tumours (80% 5-year specific survival). The surgical management of upper urinary tract tumours is gradually evolving towards complete preservation of the upper urinary tract and renal parenchyma, when compatible with local conditions. Conservative endoscopic treatments (ureteroscopy, percutaneous treatment) provide good oncological results and constitute a possible alternative to nephroureterectomy for the systematic management of good prognosis tumours. The cost of endoscopy equipment and consumable items is currently a limiting factor to the widespread use of these techniques.

Carcinoma, Transitional Cell↗

PubMed2005

Can ureteral stent encrustation analysis predict urinary stone composition?

OBJECTIVES: To determine the value of mid-infrared spectroscopy (MIRS) of ureteral stent encrustations in predicting urinary stone composition. METHODS: A retrospective study analyzed the composition of stent encrustations and urinary stones by MIRS in patients who had had a stent for ureteral obstruction between 2001 and 2003. The overall correlation was evaluated. The correlation coefficient kappa for agreement between the proportions of each component was calculated. RESULTS: A total of 72 stents and 72 stones from 72 patients were analyzed. The mean stent indwelling time was 55.5 days (range 14 to 102). The stents had been placed for fever (52 cases, 72%), pain refractory to analgesics (15 cases, 21%), and impairment of kidney function (5 cases, 7%). The overall correlation between stone composition and stent encrustation was 71.4%, excluding biofilm analysis. The kappa value was 0.78 for the main component (n = 72; P < 0.0005), 0.61 for the secondary component (n = 72; P < 0.0005), and 0.91 for the agreement between the composition of encrustations at each end of a stent (n = 30; P < 0.0005). CONCLUSIONS: MIRS analysis of stent encrustations is a reliable method of predicting stone composition when the stone cannot be retrieved. Systematic MIRS analysis of stent encrustations is not recommended but can be very useful in clinical situations in which no stone is available.

Adult↗

PubMed2005

[How to identify the neck of a caliceal diverticulum in flexible ureterorenoscopy].

A caliceal diverticulum corresponds to a cavity communicating with the renal excretory tract via a neck. Surgical treatment is required when the caliceal diverticulum is symptomatic with repercussions on the patient's quality of life. A retrograde approach via holmium:YAG laser ureterorenoscopy has been recently used to treat the stone and externalize the caliceal diverticulum into the pyelocaliceal cavities. The problem raised by this approach is identification of the diverticular neck. The objective of this technical note is to describe a technique to facilitate identification of the diverticular neck.

Diverticulum↗

PubMed2005

[Management of priapism in patients with sickle-cell anaemia].

Sickle-cell anaemia is an autosomal recessive hereditary haemoglobinopathy. Patients with sickle-cell anaemia present a high risk of priapism. At least 40% of sickle-cell patients report episodes of priapism. Priapism in patients with sickle-cell tend to start during childhood and rapidly threaten the erectile prognosis. Apart from specific treatment of sickle-cell anaemia, the urologist must be able to recognize forms of intermittent priapism and promote medical prevention. The urologist must also be able to distinguish low-flow priapism from the rarer high-flow priapism, as the treatments differ. Treatment strategies are increasingly well defined, with an increasingly limited place for surgery.

Anemia, Sickle Cell↗

PubMed2005

[Value of infrared spectrophotometry morpho-constitutional analysis of double J stent encrustations for indirect determination of urinary stone composition].

INTRODUCTION: A single stone analysis is necessary during the patient's clinical history in order to institute specific drug treatment and health and dietary measures to prevent stone recurrence. In practice, only one in every two stones is recovered for morpho-constitutional analysis. The objective of this study was to determine the place of double J stent encrustation analysis for indirect determination of stone composition. MATERIAL AND METHODS: Double J stents and stones from all patients treated in the same centre over 24 months were consecutively analysed by infrared spectrophotometry. The correlation coefficient 1, evaluating the concordance between the composition of stones and double J stent encrustation was estimated statistically by SPSS 12.0 software (0<1<1; 1=0: no concordance; 1=1: perfect concordance). RESULTS: 45 males and 27 females with a mean age of 45.3 years (range: 29-70) were included Double J stents were placed for: febrile obstruction (N=52; 72%), acute renal colic (N=15; 21%) and impaired renal function (N=5; 7%). Calculated values for 1 were: 0.78 for the concordance between the predominant constituent of the stone and the encrustation (N=72; p < 0.0005); 0.91 for the concordance between the nature of the encrustation of the upper loop and that of the lower loop of the stent (N=30, p < 0.0005). CONCLUSION: The composition of mineral encrustation of double J stents is a good marker of stone formation. This constitutes an alternative method that can be used by urologists when no stone is available for spectrophotometric analysis.

Adult↗

PubMed2005

[How to avoid accumulation of stone fragments in the lower calix during flexible ureterorenoscopy].

Flexible ureterorenoscopy combined with Holmium:YAG laser is an emerging technology that already has its place among the urologist's treatment options for the management of urinary stones. The main indication for the technique is renal stones, particularly lower caliceal stones. After mobilization of the stone in the renal pelvis or upper caliceal group, fragmentation is achieved by Holmium:YAG laser and the largest fragments are removed. When small fragments persist that are difficult to extract, the patient's blood is injected into the lower caliceal group to obtain a blood clot This clot then fills the lower caliceal group and prevents secondary accumulation of residual stone fragments, facilitating elimination of fragments towards the ureter. This article describes this technique.

Humans↗

PubMed2005

[Comparative study of two latest generation flexible ureterorenoscopes].

INTRODUCTION AND OBJECTIVES: Miniaturization and development of flexible instruments have led to the development of flexible ureterorenoscopy. The objective of this study was to compare the capacities of active deflection of two latest generation flexible ureterorenoscopes and to evaluate alteration of deflection and flow of irrigating fluid in the presence of instruments in the operating channel. MATERIAL AND METHODS: Two ureterorenoscopes were evaluated in this study. The Karl STORZ Flex-X and the ACMI DUR-8 Elite. Comparison of deflection movements was performed ex situ by super-imposing all active movements of the two ureterorenoscopes. Alteration of deflection was performed by alternately placing an extraction or fragmentation instrument of variable dimensions in the operating channel. Alteration of flow was also assessed in the presence of the same instruments. RESULTS: The ex situ deflection capacities of the DUR-8 Elite flexible ureterorenoscope were more extensive than those of the Flex-X, but it was more complicated to manipulate. Alterations of deflection and flow of irrigation fluid were comparable for the two ureterorenoscopes. CONCLUSION: On the basis of these data, we can confirm that the two latest generation ureterorenoscopes present comparable capacities, but different functioning modalities. We therefore recommend that each operator test the two ureterorenoscopes to become familiar with their manipulation. Other studies are necessary to evaluate the optical properties, ease of use in clinical practice and fragility of these new ureterorenoscopes.

Equipment Design↗