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Francis Dubosq

Publications and source records attributed to Francis Dubosq.

13 recordsLinked to original sources

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↗

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↗

[How to anticipate specialization at the Examen National Classant (National Entrance Examination) to encourage interns to choose urology].

OBJECTIVES: To analyse the value of an introduction to urology session to recruit interns following the Examen National Classant (ENC) (National Entrance Examination). MATERIALS AND METHODS: Over a 2-year period, interns appointed to surgery in Paris participated in a one-day introduction to urology session before starting work as surgical interns. A questionnaire at the beginning of internship recorded: age, gender, teaching hospital, student attachment in urology and desired specialization as a function of the surgical training programmes proposed by the ENC. Items concerning the desired specialization were resubmitted to the interns at the end of the session. RESULTS: Population. 166 interns, 98 females (59%) and 68 males (41%) with a mean age of 24.8 +/- 5 years (range: 22-31) participated in this study. 110 interns had trained at a Parisian teaching hospital (66.2%) and 56 (33.8%) had trained at a provincial teaching hospital. 31 interns (18.7%) had completed at least one urology attachment during their medical training. Desired specialization: Orthopaedics was the discipline most frequently cited (n=48; 28.9%). Urology was selected by 19 interns (11.4%), 17 of whom had completed an urology attachment during their medical training. At the end of the introduction to urology session, another 15 interns initially oriented towards other specializations were interested in urology training. CONCLUSION: Specialization of certain surgical disciplines during internship could become inevitable in the medium term. In this case, the organization of national introduction to urology sessions in each ENC allocation region would be a solution to encourage motivated interns to immediately choose urology as their surgical speciality by preference rather than by default.

Adult↗

[Renal cell carcinoma and trichloroethylene].

The authors report the case of a 51-year-old man with a history of trichloroethylene (TCE) poisoning. He was treated by radical nephrectomy after discovery ofa right renal mass corresponding to renal cell carcinoma. The objective of this study is to discuss the role of TCE abuse as a renal carcinogen. TCE is an excellent solvent used to degrease metal parts. It can enter the body by inhalation, ingestion or cutaneous contact, but the respiratory tract is the main route of absorption of TCE. Many epidemiological studies have been conducted on workers exposed to TCE, but they have not been able to clearly establish a link between exposure by inhalation to TCE and cancer. The International Agency for Research on Cancer has accumulated sufficient evidence to consider TCE to be carcinogenic to animals and considers that TCE is probably carcinogenic to humans. Toxic metabolites derived from TCE induce chronic renal tubular lesions and may exert a genotoxic effect on the proximal convoluted tubule. The initial genotoxic effect appears to be related to mutations of the VHL suppressor gene. The chronic toxic effects and the possible role of TCE in the development of cancer have not been specifically studied in the context of TCE abuse behaviour. To our knowledge, this is the first case of renal cell carcinoma reported in a TCE addict.

Carcinoma, Renal Cell↗

[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↗

[Improvement of the recruitment of surgery interns derived from the Epreuves Nationales Classantes (National-Ranking Exam): practical solution applied to urology].

OBJECTIVES: To analyse the value of an urology initiation session proposed to young interns to improve recruitment of the discipline since the introduction of the new National-Ranking Exam (NRE). MATERIALS AND METHODS: In October 2004, the 77 interns appointed to surgery in Paris on the basis of the ENC participated in a one-day urology initiation session organized by the AFUF, at the AP-HP School of Surgery. All interns were given a questionnaire at the beginning of the session to record the following data: age, gender, teaching hospital, a student attachment in urology and desired specialization as a function of the surgical training programmes proposed by the ENC. Items concerning the desired specialization were resubmitted to the interns at the end of the session. RESULTS: Population. 77 interns, 48 females (62.3%) and 29 males (37.7%) with a mean age of 25.2 +/- 5 years (range: 23-31). 55 interns had trained at a Parisian teaching hospital (67%) and 22 (28.6%) had trained at a provincial teaching hospital. 16 interns (20.8%) had completed at least one urology attachment during their medical training. Desired specialization. Orthopaedics was the discipline most frequently cited (n = 20; 26%). Urology was chosen by 8 interns (10.40%), who had all completed an urology attachment during their medical training. At the end of the urology initiation session, another 8 interns expressed the desire to specialize in urology. Of the 16 potential urology interns, 9 (56.2%) confirmed that their decision was final. CONCLUSION: Urology occupies a special place and remains a popular surgical speciality among students. Organization of practical sessions constitutes a solution to inform, create an emulation and motivate surgery interns to choose urology.

Adult↗

[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↗

[Endoscopic lithotripsy and FREDDY laser technology. Initial experience].

INTRODUCTION AND PURPOSE: FREDDY laser technology was developed for endocorporeal lithotripsy. The purpose of this study was to evaluate, based on our initial experience, the efficacy and place of this technology in the treatment of urinary calculi by ureterorenoscopy. (World of Medicine) to treat 26 patients (29 stones) by ureterorenoscopy. This was the second procedure for 25 stones: after ESWL (23 cases) or percutaneous nephrolithotomy (2 cases) and the first procedure for 4 stones. The mean stone diameter was 9 mm (range: 6-15 mm). Thirteen stones were situated in the kidney and 16 were in the ureter. Success of treatment was defined by the absence of residual fragments immediately after the operation or at one month on plain abdominal x-ray. RESULTS: Twenty-six stones were satisfactorily fragmented. At three months, 21 out of 26 (80.7%) patients were stone-free corresponding to 21 out of 29 (72.4%) stones). Failures concerned 8 stones (5 patients). For five stones, measuring more than 10 mm, residual fragments persisted at three months. For three other stones, two cystine stones and one calcium oxalate monohydrate stone, fragmentation was insufficient or even nonexistent for the cystine stones. The mean length of hospital stay was 1.5 days (range: 1-3 days). A ureteric perforation due to a stone impacted in the ureteric wall was observed. CONCLUSIONS: FREDDY laser endoscopic lithotripsy is a safe and effective method due to the wavelength used. This laser could constitute an alternative treatment option in view of its moderate cost and the fact that it is adapted to flexible ureterorenoscopy. However, it presents certain limitations in terms of fragmentation, particularly in the case of cystine stones, and cannot be used to treat solid lesions (urinary tract strictures and tumours).

Adult↗

Impact on active scope deflection and irrigation flow of all endoscopic working tools during flexible ureteroscopy.

OBJECTIVE: Flexible ureteroscopy is nowadays an alternative effective option for treatment of upper urinary tract stones, especially in the lower renal pole. Access in this case is often limited by active deflection capabilities of the instrument which is always deteriorated by the passage of different tools through the working channel. Insertion of them limits also the irrigation flow and so that the visibility. These deteriorations vary largely following the tool inserted. We performed an in vitro evaluation of deterioration of active deflection, possibility of tool insertion in maximal active deflection and irrigation flow in 6 different flexible ureteroscopes with almost all of tools available. METHODS: A total of 546 measures of maximal deflection, test of passage of tools in maximal deflection and measures of irrigation flow passage through the working channel were made on 6 different ureteroscopes, the ACMI DUR-8, the ACMI DUR-8 "Elite", the Karl Storz 11274 AA, the Karl Storz 11278 AU1 "Flex-X", the Wolf 7325.172 and the Olympus URF/P-3 without any tool inserted and with 22 different tools (14 extraction devices and 8 lithotripsy probes). RESULTS: Larger caliber tools resulted in more deflection degradation than smaller ones but it is more evident in case of use of non-nitinol tools instead of the nitinol ones. Generally lithotripsy probes affected active deflection more than nitinol extractions tools but different brand laser fibres present different results. Usually 1.6 and 1.9F electro hydraulic probes offer a slightly better deflection than does the 200micro laser fibre. Ballistic shock probes are so stiff that can not be used for treating lower renal pole stones. CONCLUSIONS: An array of different instruments are nowadays available for upper renal endoscopic treatment but they differ largely on stiffness and on obstruction to irrigation flow. Laser probes are very problematic to insert in the already deflected instruments, something that is less evident with the EHL probes and the smaller nitinol extraction tools. Irrigation flow is inversely proportional to the diameter of the tool inserted. Tools with a diameter of 3 French or more block totally the flow.

Equipment Design↗

[Management of dog bite trauma of the external genital organs].

Animal bites to the scrotum are rare, but potentially serious. In the light of a personal case, the authors discuss the management of these lesions. An animal bite comprises a triple infectious risk: bacterial, tetanus and rabies. Surgical exploration is indicated for assessment of the structures involved and debridement. The morbidity is related to the severity of the bite and the waiting time before consultation, and complications are rare. Orchidectomy is sometimes necessary, as in the case reported here, and the patient must be warned about this possibility. Antibiotic therapy is empirical: tetracycline and anti-anaerobe antibiotic. Rabies and tetanus prophylaxis must be performed according to vaccine guidelines.

Aged↗

[Spontaneous renal haematoma: diagnostic and therapeutic approach in 7 cases].

OBJECTIVE: Spontaneous renal haematomas are rare. The authors discuss the aetiological diagnosis and management of these haematomas. MATERIAL AND METHODS: Seven cases (3 females and 4 males) of spontaneous renal haematoma were managed between July 1999 and December 2002 and the case files were studied retrospectively. RESULTS: The circumstances of discovery were nonspecific. One patient presented with haemorrhagic shock. Radiological work-up comprised abdominal ultrasound and CT scan in almost every case. Ultrasound failed to demonstrate the aetiological diagnosis. CT revealed the cause of bleeding in 7 cases. MRI was performed in 4 cases, but urgent angiography was not performed. Four total nephrectomies were necessary, while two patients were treated by conservative surgery. One patient was simply followed by repeat CT scan. The short-term course was favourable with a mean follow-up of 23 months. CONCLUSION: Spontaneous renal haematomas raise 2 problems, that of their aetiology: tumours are the commonest causes (angiomyolipoma and renal cell carcinoma), and that of their management. Three therapeutic approaches are possible: radical surgery in the case of uncontrollable bleeding, conservative surgery or surveillance in the absence of a life-threatening emergency and when the aetiological diagnosis has not been established. Rigorous and repeated radiological surveillance can identify the cause of the bleeding allowing conservative surgery to be performed when indicated.

Aged↗

[Flexible double active deflection ureterorenoscopy].

INTRODUCTION AND OBJECTIVE: Secondary deflection of a flexible ureterorenoscope (FUR) is a passive mechanism, which can only be performed under certain anatomical conditions. The objective of this study was to present a new double active deflection FUR and to assess its value based on our initial experience. MATERIAL AND METHODS: From October 2002 to February 2003, we performed flexible retrograde ureterorenoscopy in 30 consecutive patients (34 renal units) using a double active deflection FUR (ACMI DUR 8 Elite). Bilateral ureterorenoscopy was performed during the same operating time in four patients. Ureterorenoscopy was diagnostic for 9 patients (macroscopic haematuria, urinary tract tumour), and therapeutic for 21 patients (stones, urinary tract tumour, ureteropelvic junction stenosis with stone). The value of double deflection as well as the efficacy and morbidity of the technique were evaluated. RESULTS: The main indication for flexible ureterorenoscopy was the treatment of urinary stones (73.6%), followed by the diagnosis of macroscopic haematuria and urinary tract tumours (26.4%). Ureteric dilatation was necessary in 38.3% of cases. The use of active secondary deflection was essential in 20% of cases (7/34) for complete investigation of the pyelocaliceal cavities. Access to the lower calices was not possible in one patient with a left pelvic kidney. 19 patients with urinary stones had no fragments (79.2%) at the end of the operation, while 4 had residual fragments in the lower calices. The global success rate for all operations was 85% (29/34). Two patients developed acute pyelonephritis during the 48 hours after the procedure and another two patients experienced acute renal colic. CONCLUSIONS: Our study confirms the data of the literature on flexible ureterorenoscopy in terms of indications and efficacy. The URS DUR 8 Elite allowed complete exploration of the pyelocaliceal cavities in more than 97% of cases. The use of active secondary deflection was unnecessary for the majority of patients (80%), but it represents a major technical progress which should be taken into account in the design of future flexible ureterorenoscopes.

Adult↗