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J E Lingeman

Publications and source records attributed to J E Lingeman.

At least 19 recordsLinked to original sources
PubMed1998

Lower-pole caliceal stone clearance after shockwave lithotripsy, percutaneous nephrolithotomy, and flexible ureteroscopy: impact of radiographic spatial anatomy.

Spatial anatomy of the lower renal pole, as defined by the infundibulopelvic angle (LIP angle), infundibular length (IL), and infundibular width (IW), plays a significant role in the stone-free rate after shockwave lithotripsy. A wide LIP angle, a short IL, and a broad IW, individually or in combination, favor stone clearance, whereas a LIP <70 degrees, an IL >3 cm, or an IW < or =5 mm are individually unfavorable. When all three unfavorable factors or an unfavorable LIP and IL coexist, the post-SWL stone-free rate falls to 50% or less. Using these criteria, more than one fourth of our patients with a lower-pole calculus might have been better served by an initial percutaneous or perhaps ureteroscopic procedure, neither of which is significantly affected by the lower-pole spatial anatomy.

Adolescent↗
PubMed1998

High-speed photographic evaluation of holmium laser.

Little information has been published regarding the relative contributions and exact mechanisms involved in stone fragmentation during holmium laser lithotripsy. High-speed photography has been used to evaluate other intracorporeal lithotripsy devices, and we chose this method to evaluate the holmium laser. High-speed photographic evaluation of cavitation bubbles produced by the four fiber sizes (200, 365, 550, and 1000 microm) showed a moderate degree of correlation (n = 0.71 for 1 J pulses, r = 0.80 for 4 J pulses) between maximal bubble size and fiber diameter. Eliminating the data from the eroded 550 microm fiber strengthened the correlation to r = 0.94 for 1 J pulses and r = 0.99 for 4 J pulses. The importance of keeping fiber tips in good working condition was thereby demonstrated. Evidence of a thermal effect of the laser on stone and chalk was also obtained. In a parallel study, no correlation (r = -0.08) was found between fiber diameter and stone fragmentation efficiency using chalk as an in vitro stone model.

Calcium Carbonate↗
PubMed1998

Alterations in predicted growth rates of pediatric kidneys treated with extracorporeal shockwave lithotripsy.

The long-term effects of extracorporeal shockwave lithotripsy (SWL) on the kidneys of children treated for renal calculi are unclear. In order to determine if SWL has any negative effects on renal growth rates, we reviewed long-term (mean 9-year) follow-up data on 29 pediatric patients treated between 1984 and 1988 with an unmodified Dornier HM3 lithotripter. Changes in renal length, serum creatinine, and blood pressure were analyzed. Predicted renal growth was calculated using a formula for age-adjusted renal length. Treated kidneys were stratified into normal and abnormal groups based on a history of renal surgery, evidence of recurrent infection, and obvious anatomic abnormalities. Fifty-six upper urinary tract calculi were treated in 34 renal units. Twenty-two renal units (68%) were rendered stone free, and 65% of the patients continue to be stone free. At follow-up, one patient was classified as having new-onset hypertension, and the mean serum creatinine was 0.93 +/- 0.08 mg/dL. Both at treatment and at follow-up, no significant differences were found in the sizes of the treated and untreated kidneys. However, at treatment, the abnormal group of kidneys seemed to be smaller than expected (mean Z -1.30 +/- 1.10), whereas the group of normal kidneys was very close (mean Z 0.18 +/- 0.54) to the predicted length. At follow-up, the deviations between actual and predicted renal length were significantly more negative. Treated kidneys were an additional 1.26 +/- 0.49 SD units below their expected length (p = 0.02). Untreated kidneys were further below normal as well but possibly to a lesser degree (-0.82 +/- 0.36; p <0.04). Although there was a trend for the abnormal group to have smaller kidneys than the normal group, both groups showed the same trend toward an age-adjusted reduction in renal growth at follow-up. The alterations in renal growth patterns observed in this population are unsettling and could be secondary to either treatment effect (SWL) or, more likely, to some underlying pathology intrinsic to pediatric kidneys with urolithiasis. Until further data are available, SWL in the pediatric population should be applied with caution and at the lowest dosage sufficient to achieve stone comminution.

Adolescent↗
PubMed1997

Quantitation of shock wave lithotripsy-induced lesion in small and large pig kidneys.

BACKGROUND: Shock wave lithotripsy (SWL) is known to cause injury to the kidney. However, it is not known how lesion size varies as the parameters of SWL treatment (number of shocks, kilovoltage, kidney size) are changed. This hypothesis could not be tested because there was no method available to quantitate accurately the SWL-induced renal lesion. METHODS: A dosage of 2,000 shocks at 24 kV delivered by an unmodified Dornier HM3 lithotripter was applied to the lower pole calyx of the right kidney of small and large pig kidneys. A new method was developed to embed a whole pig kidney for serially sectioning, recording, and digitization. Automated computer color recognition made it possible to discriminate regions of hemorrhage from undamaged tissue and allowed quantitation of the lesion in single sections and in the entire kidney. RESULTS: The new protocol resulted in an accurate identification of sites of hemorrhage and calculations of the volume fraction of injured renal tissue. Lesion size induced in small kidneys was significantly larger than that induced in the larger kidneys (7.6 +/- 1.2% and 1.6 +/- 0.7%, respectively). CONCLUSIONS: Computer segmentation of serially sectioned SWL-treated kidneys has determined that kidney size is a risk factor for enhanced renal injury.

Animals↗
PubMed1997

Ureteral Stones Clinical Guidelines Panel summary report on the management of ureteral calculi. The American Urological Association.

PURPOSE: The American Urological Association convened the Ureteral Stones Clinical Guidelines Panel to analyze the literature regarding available methods for treating ureteral calculi and to make practice policy recommendations based on the treatment outcomes data. MATERIALS AND METHODS: The panel searched the MEDLINE data base for all articles related to ureteral calculi published from 1966 to January 1996. Outcomes data were extracted from articles accepted after panel review. The data were then meta-analyzed to produce outcome estimates for alternative treatments of ureteral calculi. RESULTS: The data indicate that up to 98% of stones less than 0.5 cm. in diameter, especially in the distal ureter, will pass spontaneously. Shock wave lithotripsy is recommended as first line treatment for most patients with stones 1 cm. or less in the proximal ureter. Shock wave lithotripsy and ureteroscopy are acceptable treatment choices for stones 1 cm. or less in the distal ureter. CONCLUSIONS: Most ureteral stones will pass spontaneously. Those that do not can be removed by either shock wave lithotripsy or ureteroscopy. Traditional blind basket extraction, without fluoroscopic control and guide wires, is not recommended. Open surgery is appropriate as a salvage procedure or in certain unusual circumstances.

Humans↗
PubMed1997

Simultaneous bilateral percutaneous nephrolithotomy.

PURPOSE: We evaluate the results of simultaneous bilateral percutaneous nephrolithotomy. MATERIALS AND METHODS: The charts of 52 patients scheduled for simultaneous bilateral percutaneous nephrolithotomy at the Methodist Hospital of Indiana were retrospectively reviewed. The results of the 48 patients who underwent the procedure were tabulated and analyzed. RESULTS: Mean operative time was 269 minutes and mean hospital stay was 5.6 days. Of the patients 45 were rendered stone-free (96.9% of 96 renal units) and 3 had insignificant debris (fragments less than 4 mm.) unilaterally. Complications were infrequent and included hydrothorax in 5 cases, ureteral obstruction by fragment migration in 2, hematuria causing clot retention in 2, blood transfusion in 2 and ureteral perforation with a guide wire in 1. CONCLUSIONS: Simultaneous bilateral percutaneous nephrolithotomy is a well tolerated, safe, cost-effective and expeditious approach to patients with bilateral renal calculi requiring percutaneous nephrolithotomy.

Adolescent↗
PubMed1997

Extracorporeal shock wave lithotripsy. Development, instrumentation, and current status.

In this article, the author briefly reviews the early development of the lithotriptor, provides a detailed review of lithotriptors that are currently available, and gives an overview of the present extracorporeal shock wave lithotripsy indications and techniques. The author also presents a brief overview of the results that are produced by various lithotriptors.

Anesthesia↗
PubMed1997

Effects of SWL on glomerular filtration rate and renal plasma flow in uninephrectomized minipigs.

This study tested the hypothesis that the effects of SWL on hemodynamics in solitary kidneys differ from those in kidneys of binephric animals. Five female miniature pigs (Pitman-Moore, 6 months of age, 30-35 kg) were anesthetized for unilateral nephrectomy. Seven pigs served as binephric controls. Two weeks later, each pig was anesthetized, prepared for unilateral or bilateral urine collections, and subjected to SWL (Dornier HM3, 2000 shocks, 24 kV). Clearances of inulin (glomerular filtration rate; GFR) and para-aminohippurate (renal plasma flow; RPF) were measured 1 hour prior to and 1, 4, and 24 hours after SWL. The GFR and RPF were higher in uninephrectomized than in intact pigs at all time points. In both groups, SWL reduced GFR and RPF. In the binephric pigs, RPF was reduced at all times post-SWL, but in the uninephrectomized pigs, RPF was returning toward baseline by 4 hours post-SWL and was not different from baseline at 24 hours. A comparison of whole-animal GFR and RPF (righ plus left clearances in binephric pigs v solitary renal clearances in uninephrectomized pigs) showed that whole-animal GFR and RPF did not differ between the groups before or after SWL. Compensatory renal hypertrophy and improved hemodynamics in solitary kidneys may acutely attenuate the renal vasoconstrictive effect of SWL. The long-term consequences of the compensatory changes are unknown.

Animals↗
PubMed1997

Urologic applications of the Holmium laser.

The Holmium laser has now been in clinical use in urology for several years. The indications for its use continue to expand, and now include lithotripsy and urothelial tumor ablation anywhere in the urinary tract, resection of the prostate, incision of various urinary tract strictures, and vaporization of cutaneous lesions of the external genitalia. The 2100-nm wavelength provides the Holmium laser with a unique combination of vaporization and coagulation, allowing a precise cutting action when higher energy levels are applied. A shallow depth of penetration (< 0.5 mm) in water and tissue allows precise energy application and provides a margin of safety. The machine's user-friendly setup facilitates its operation by urologists and assistance by allied health-care personnel. The multiple urologic applications make the Holmium laser an attractive instrument for everyday utilization by any medium to large urological unit.

Clinical Trials as Topic↗
PubMed1996

Use of extracorporeal shock wave lithotripsy for treatment of nephrolithiasis and ureterolithiasis in five dogs.

The safety and efficacy of extracorporeal shock wave lithotripsy in 5 dogs with nephrolithiasis and ureterolithiasis was assessed. Three dogs had bilateral nephrolithiasis, 1 had bilateral nephrolithiasis and unilateral ureterolithiasis, and 1 had unilateral nephrolithiasis and unilateral ureterolithiasis. A first-generation lithotriptor was used for all treatments. None of the dogs developed clinically important complications during or after treatment, except for 1 dog treated for bilateral nephrolithiasis that developed transient ureterolithiasis. Renal function was unchanged in all dogs following treatment. Clinical signs resolved in all dogs. Extracorporeal shock wave lithotripsy appears to be a safe and effective means of treating nephrolithiasis and ureterolithiasis in dogs and appears to cause less renal parenchymal damage and renal function loss than does nephrotomy.

Animals↗
PubMed1996

Branching patterns of the renal artery of the pig.

BACKGROUND: The pig kidney is similar in structure and function to the human kideny, thus making it a useful model in understanding the human kidney in health and disease. However, little is known about the branching pattern of the pig renal artery as compared with the human and other animals. METHODS: The right and left kidneys from 11 juvenile pigs were injected with either Mercox compound to form a vascular cast or contrast media to obtain a renal arteriogram. Branching patterns of the renal artery were then examined to the level of the interlobar arteries. RESULTS: Examination of all 22 kidneys showed the main stem renal artery branching into two predictable patterns, designated I and II. The renal artery in pattern I (17 of 22 kidneys) divides into upper and lower polar arteries that then form anterior and posterior segmental arteries. Pattern I has two variations. Pattern II (5 of 22 kidneys) has a variable blood flow to the upper pole. Not only do anterior and posterior segmental arteries pass to the upper pole, but additional vessels arising from the lower polar artery also supply the upper pole. CONCLUSIONS: The most common branching pattern of the main stem renal artery is pattern I, which divides the blood flow of the entire kidney into two distinct regions. Pattern II is less frequently seen and shows more variability in number and location of branches.

Animals↗
PubMed1996

Value of laparoscopy in the management of calculi complicating renal malformations.

A minimally invasive approach for urolithiasis patients with complex anatomic abnormalities occasionally necessitates the use of laparoscopic techniques, either alone or in combination with endourologic techniques. The management of these patients is best accomplished in centers with the facilities to provide a spectrum of endourologic and laparoscopic techniques. Two illustrative cases are described.

Aged↗
PubMed1996

Lithotripsy and surgery.

Advances in surgical techniques have dramatically altered the management of patients with symptomatic urolithiasis requiring intervention. Extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy, and ureteroscopy allow virtually any stone to be removed from the upper urinary tract without resorting to open surgical techniques. Extracorporeal shock wave lithotripsy is the preferred initial treatment for approximately 80% to 85% of calculi. Percutaneous nephrolithotomy is the preferred approach when dealing with more voluminous stone material (ie, > 2 cm). Ureteroscopy is generally reserved for distal ureteral calculi, although the recent advent of small flexible ureteroscopes have extended ureteroscopic techniques effectively into the proximal ureter and even the kidney. Staghorn stones are usually best managed initially with percutaneous nephrolithotomy followed by the addition of extracorporeal shock wave lithotripsy, if necessary. The relative advantages, disadvantages, and complications of extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy, and ureteroscopy will be reviewed.

Equipment Design↗
PubMed1995

Stones.

Explore the source record for details and available documents.

Colic↗
PubMed1995

Endoscopic management of total ureteral occlusion and ureterovaginal fistula.

Between August 1991 and June 1994, endoureterotomy was performed in nine patients for total ureteral occlusion. Four of these patients had an associated ureterovaginal fistula. The total ureteral occlusions were iatrogenic in eight patients and the result of trauma in one. The prone split leg position was used to facilitate simultaneous antegrade and retrograde ureteroscopy in all nine patients. The "cut-to-the-light" technique was utilized in six patients and a new technique employing a fascial incising needle was used in five patients. Five patients developed ureteral strictures within 5 months of the primary procedure that were corrected endoscopically. With a mean follow-up of 22 months, all nine patients have a successful outcome. Endoscopic management of difficult urteral disease such as total urteral occlusion and ureterovaginal fistula is a useful alternative to open surgery.

Adult↗
PubMed1995

Metabolic evaluation of infected renal lithiasis: clinical relevance.

Complete metabolic evaluation was performed in 21 patients with infected renal lithiasis. Patients with pure struvite stones (struvite +/- carbonate apatite) were significantly less likely to have metabolic abnormalities than patients who had struvite +/- carbonate apatite+calcium oxalate (2 of 14 v 7 of 7, P = 0.0003). Urine calcium excretion was markedly higher in the mixed stone group than the pure struvite group (342 +/- 98 mg/24 h v 136 +/- 82 mg/24 h; P < 0.0001). The differing opinions among researchers regarding the likelihood of finding metabolic abnormalities in patients with urolithiasis and infection probably reflect differences in the definitions of the populations studied. If patients with calculi containing only struvite +/- carbonate apatite are evaluated, we believe that few significant metabolic abnormalities will be identified.

Adolescent↗
PubMed1995

Shock wave lithotripsy with the Dornier MFL 5000 lithotriptor using an external fixed rate signal.

PURPOSE: We examine the effects of fixed rate shock wave administration on the cardiac rhythm and treatment efficacy of a tubless lithotriptor (Dornier MFL 5000*). A secondary goal was to examine the treatment efficacy of fixed shock wave administration compared to R wave triggered lithotripsy. MATERIALS AND METHODS: In this prospective study Holter monitoring was used before, during and after nonR wave triggered shock wave lithotripsy. RESULTS: An increase in premature ventricular contractions was noted during shock wave lithotripsy. However, there were no episodes of significant ventricular ectopia, ventricular tachycardia, asystole or heart block as a result of nonR wave triggered shock wave administration. NonR wave gated shock wave lithotripsy expedited patient treatment and (mean treatment time 46 +/- 21 minutes)., minimized the use of sedation during treatment and produced results similar to R wave gated shock wave lithotripsy with the MFL 5000 lithotriptor. CONCLUSIONS: With adequate precautions, fixed rate shock wave administration would appear to be a reasonable option to treat urolithiasis with the MFL 5000 lithotriptor as with other newer lithotriptors.

Adult↗