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G J Fuchs

Publications and source records attributed to G J Fuchs.

8 recordsLinked to original sources

Fitting growth curve models to longitudinal data with missing observations.

We discuss the analysis of growth curve data with missing or incomplete information. The approach is to fit subject-specific models and then to carry out an analysis in terms of the estimated parameters. This achieves reduction of data and eliminates the need for special considerations for subjects with missing data. Although there is no perfect substitute for complete data, our approach provides a way to handle missing data using a straightforward application of well-known statistical methodology.

Cephalometry

[Flexible endoscopy of the upper urinary tract. A new minimally invasive method for diagnosis and treatment].

Retrograde intrarenal surgery (RIRS) utilizing flexible, actively deflectable instruments has become a valuable asset in the diagnosis of upper urinary tract pathology and the treatment of stone disease. Flexible endoscopic surgery of the proximal ureter and in the intrarenal collecting system constitutes the natural extension of rigid instrumentation in the upper urinary tract. At our institution retrograde ureteral and intrarenal surgery has become an +integral part of our diagnostic and therapeutic armamentarium. This is documented by almost 300 treatments and diagnostic procedures performed in the upper urinary tract over the past 3 years.

Carcinoma, Transitional Cell

Current state and future developments of noninvasive treatment of human urinary stones with extracorporeal shock wave lithotripsy.

Extracorporeal shock wave lithotripsy has now been in clinical use for 8 years and it has replaced other treatment techniques for the majority of surgical calculi in the upper urinary tract. For the first time it provides a completely noninvasive method for the treatment of renal and ureteral stones. The current range of its indications includes approximately 70 per cent of nonselected urinary stone patients. An additional 25 per cent of the patients with more complex stones in the upper urinary tract can receive treatment with the lithotriptor combined with endourological procedures. More recent additions to the range of clinical routine applications with the original lithotriptor have been its use on common bile duct stones combined with endosurgical or radiological manipulations. With a modified kidney lithotriptor gallstones have been treated successfully, which has led to the development of a multipurpose device for biliary and urinary stones.

Humans

Extracorporeal shock-wave lithotripsy of bile duct calculi. An interim report of the Dornier U.S. Bile Duct Lithotripsy Prospective Study.

A multi-institutional study to evaluate the efficacy, clinical application, and safety of extracorporeal shock-wave lithotripsy (ESWL) with the Dornier HM-3 or HM-4 lithotripter for bile duct calculi (BDC) was initiated in September, 1987. Symptomatic patients who entered into this prospective trial had BDC in the common bile duct and/or the intrahepatic, cystic or lobar ducts of the liver that were inaccessible or untreatable by papillotomy or percutaneous stone extraction. The study excluded gallbladder stones. Nasobiliary (54.4%) or transhepatic catheters (10.5%) and T-tube or cholecystostomy tubes (17.5%) or combinations (14.0%) permitted access for radiographic contrast to allow fluoroscopic monitoring of stone position and fragmentation. Exclusion criteria included pregnancy, failure to localize the stone, disturbances of coagulation, pacemakers, or vascular aneurysms or large bones that lie in the focal axis of the shock waves. Eleven institutions treated 42 patients (23 male, 19 female) with BDC; age range was 25 to 95 years (mean +/- SD, 73.5 +/- 13.8) and ASA risk category was 1 to 4 (mean, 2.3 +/- 0.8). Fourteen patients (33.3%) had a single BDC; 28 had 2 to 8 stones (mean, 2.7 +/- 1.8) ranging in size from 6 mm to 30 mm (mean, 18.5 +/- 6.4). The majority (66.7%) of patients were postcholecystectomy. The 42 patients received 57 ESWL treatments consisting of 600 to 2400 shocks per treatment (mean, 1924 +/- 289) at 12 to 22 kV (mean, 18.5 +/- 1.9) administered over 20 to 125 minutes (mean, 52.9 +/- 20.8). General anesthesia was used in 32% of the treatments; the majority were treated with epidural or regional block (42.1%), local infiltration (28.1%), or intravenous sedation (38.6%). Fifteen patients (35.7%) required two ESWL treatments. Stone fragmentation occurred in 94.6% of evaluable patients and in 90.4% of ESWL treatments, respectively; however, BDC fragments remained in 59.5% of patients 24 hours after treatment (diameter less than or to 3 mm, 12%; 4 to 9 mm, 16%; greater than or equal to 10 mm, 68%). Some patients (50%) required adjunctive procedures to achieve stone removal that included endoscopic extraction (n = 10; 47.6%), biliary lavage (n = 8; 38.1%), endoscopic bile duct prosthesis (n = 1; 4.8%), and operation (n = 2; 9.5%). ESWL treatment complications during hospitalization were observed in 15 patients (35.7%) and were present in four (9.5%) at discharge. Complications included macrohematuria (5%), biliary pain (15%), biliary sepsis (5%), hemobilia (10%), ileus (2.5%), and adverse pulmonary changes (7.5%). One patient developed pancreatitis before ESWL at ERCP that resolved prior to discharge.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult

Case history of a prune-belly syndrome with extracorporeal shock wave lithotripsy treatment of allograft nephrolithiasis.

This is a case history of a prune-belly syndrome with multiple urologic disorders leading to a renal transplant due to a chronic renal failure at age 8. After four allograft pyelolithotomies he was referred to us with a staghorn stone in the same graft. He was successfully treated with extracorporeal shock wave lithotripsy and a percutaneous nephrostomy and is now stone-free.

Child

[Complications of extracorporeal shockwave lithotripsy].

The authors reviewed treatments performed worldwide using extracorporeal shock wave lithotripsy since its introduction in West Germany in 1980 to determine the efficacy of this treatment modality and its potential risks. The prevention of complications related to patients or shock wave energy are discussed, as well as the cardiovascular complications related to immersion, prevention of lesions to nearby organs, treatment of ESWL-induced bleeding, treatment of post-ESWL ureteral obstruction, prevention and treatment of infection, and long-term biological effects. Currently, less than 5% of patients are excluded from treatment with ESWL due to technical reasons or increased risk of periprocedural complications. Patients with cardiac pacemakers have been treated safely. Calcifications of the ipsilateral renal artery or aorta are considered only relative contraindications. However, certain technical limitations exist; i.e., the Dornier HM-3 cannot support patients weighing more than 135 kg., and patient height is also a limiting factor. There is an impressively low incidence of complications related to the energy of the shock wave. The severity and extent of damage are dose- and pressure-dependent. The potential for induction of cardiac arrhythmias secondary to the shock wave exists; however, effective prevention is achieved by coupling the shock wave discharge to the electrocardiogram. Complications of immersion are also extremely rare and can be avoided by careful preoperative evaluation. Damage to nearby organs such as pulmonary, gastric, duodenal or colonic contusions, constitute a very infrequent complication. Elevations of liver enzymes have also been noted post-lithotripsy. However, all these changes were transient and had no significant clinical consequences. Management of post-ESWL ureteral obstruction is by endourological procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Infections

Colposcopy.

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Colposcopy