Does rapid intraoperative parathyroid hormone analysis predict cure in patients undergoing surgery for primary hyperparathyroidism? A prospective study.

BACKGROUND AND AIMS: Preoperative 99mTc-sestamibi scintigraphy is used by many surgeons to identify the anatomical location of pathological parathyroid glands in patients undergoing surgical treatment for hyperparathyroidism. However, false negative results do occur. It has been suggested that intraoperative parathyroid hormone (PTH) analysis may enhance the possibility of performing successful focused, unilateral neck surgery in these patients. This study aimed to evaluate whether an adequate fall in intraoperative parathyroid hormone values predicts the removal of all hyperfunctioning parathyroid tissue and postoperative normocalcemia. MATERIAL AND METHODS: One hundred consecutive patients undergoing surgery for hyperparathyroidism had preoperative 99mTc-sestamibi scintigraphy and intraoperative parathyroid hormone (PTH) analysis. A fall in intraoperative PTH value by more than 50% of baseline value ended the procedure. This prospective study presents the clinical and biochemical results. RESULTS: The overall sensitivity of the 99mTc-sestamib scintigraphy was 88% and for single adenomas 95%. The scintigraphy failed to detect the correct pathology in all cases with multiglandular disease (7 patients). A fall in intraoperative PTH value by more than 50% of baseline value was achieved in all patients. The combination of intraoperative PTH analysis and 99mTc-sestamibi scintigraphy enabled us to limit the operation to a focused, unilateral operation in 87 of the 100 patients. All patients were normocalcemic postoperatively. CONCLUSIONS: A fall in intraoperative PTH value more than 50 % of baseline value seems to predict postoperative normocalcemia and the removal of all hyperfunctioning parathyroid tissue. Bilateral neck exploration is avoided in the majority of patients.

Measurement of sound emission by endoscopic lithotripters: an in vitro study and theoretical estimation of risk of hearing loss in a fetus.

BACKGROUND: There is concern about applying intraureteral lithotripsy in pregnant patients, as the sound created by the equipment may damage fetal hearing. MATERIALS AND METHODS: The sound intensities produced by electrokinetic, pneumomechanic, holmium laser, ultrasound, and electrohydraulic intraluminal lithotripters were measured in an in vitro model. RESULTS: The purely mechanical modalities (electrokinetic and pneumomechanic) generated lower peak pressures than the other devices. Theoretical calculations were performed based on the fact that in vivo, the sound path and the fetal middle ear cavities are filled with fluid. Calculated pressure levels that give displacement amplitudes of the tympanic membrane, the ossicles, and the basilar membrane comparable to hearing loss risk criteria for airborne impulsive noise are greater than measured for all of the lithotripters. The fluid-filled middle ear thus seems to give the fetus protection against sound. The fluid also improves the symmetry of the cochlea structure, reducing the influence of direct bone transmission. CONCLUSIONS: The peak pressure of the sound emitted by lithotripsy in the ureter during pregnancy is unlikely to be harmful to fetal hearing. Other risk factors, such as the form of the sound waves and the pulse duration were not evaluated. The theoretical assessments are simplified, and one should be careful about drawing conclusions from theoretical considerations and calculations alone.

Gas-containing renal stones treated with percutaneous nephrolithotomy: case report.

We present a rare case of E. coli emphysematous pyelonephritis with sepsis. The radiologic presentation consisted of multiple radiolucent gas-filled, free-floating uric acid calculi in a hydronephrotic renal pelvis. The infection was treated by intravenous fluids and antibiotics and percutaneous nephrostomy drainage. The patient was rendered stone free by percutaneous nephrolithotomy and ultrasound lithotripsy.

[Surgical treatment of urolithiasis in Norway]. / Kirurgisk behandling av urolithiasis i Norge.

The aim of the study was to investigate treatment strategies for urolithiasis as they are practised in Norway today. A questionnaire was sent to the somatic hospitals in Norway. All surgical treatment of urolithiasis was to be registered over a three month period, from 1 September to 30 November 1992. 78% of the hospitals responded, and 505 patients were included in the survey. Extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy and uretero-renoscopy are well established treatment modalities in all parts of the country. The treatment practice follows the accepted international guidelines and treated at the larger treatment centres.

[Extracorporeal shock wave lithotripsy in urolithiasis. An update]. / Ekstrakorporal sjokkbølgebehandling av urolithiasis. En oppdatering.

The author discusses the present role of extracorporeal shock wave treatment of urolithiasis. The views are based on personal experience and a review of the recent literature. Compared with the original device, second generation lithotriptors have led to almost painless treatment. They are less effective in fragmenting the stones, however, which implies a higher number of repeat treatments. The indications and contraindications for extracorporeal shock wave lithotripsy have remained unchanged over the last years. In principle, stones along the whole upper urinary tract can be treated. The ideal situation is a stone in the kidney pelvis less than 2.5 cm in diameter or an unimpacted stone in the upper or lower ureter, with normal collective system anatomy. The main determinants for treatment outcome are stone burden, number, location and chemical composition, presence of infection, intrarenal anatomy and fluid dynamics. Special situations often need additional treatment with other treatment modalities. Rest fragments, even less than 4 mm, are often of clinical significance within two years of treatment. Bioeffects of extracorporeal shock wave lithotripsy include anatomical and functional alterations. Usually they are resolved within weeks. The relationship between extracorporeal shock wave lithotripsy and new onset hypertension remains unresolved.

Visual laser coagulation of the prostate using intraurethral gel anesthesia and light intravenous analgesia and sedation.

Twenty-eight patients with symptomatic bladder outlet obstruction secondary to benign prostatic hyperplasia were treated as outpatients by visual laser coagulation of the prostate using only intraurethral gel anesthesia and light intravenous sedation and analgesia. No premedication was administered. Laser coagulation was performed with the Myriadlase side-firing fiber using a standard Sharplan neodymium: YAG laser source at 40 W power setting, and 650 (516-1000) J/g of prostate tissue was delivered. Patient acceptance was favorable. All remained relaxed, cooperative, and without pain during the procedure. None of the patients required any further anesthesia. There was no significant change in blood pressure, pulse rate, or peripheral oxygen saturation measurements during the procedure. Any patient who feels comfortable with a diagnostic cystoscopy being performed using intraurethral gel anesthesia should find this anesthesia protocol acceptable for laser coagulation of the prostate.

[Visual laser coagulation for benign prostatic hyperplasia. Preliminary experiences]. / Visuell laserkoagulasjon for benign prostatahyperplasi. Preliminaere erfaringer.

A total of 28 patients with symptomatic bladder outlet obstruction due to benign prostatic hyperplasia were treated by visual laser coagulation (VLAP) performed with the Myriadlase sidefiring neodymium: YAG laser fibre at 40 Watts power. The treatment was performed as an outpatient procedure using intraurethral gel anaesthesia and light intravenous sedation and analgesia. Prostatic volume was 32 g (18-90 g), and 650 Joule per gram prostatic tissue (516-1000 J/g) was administered. The patients were evaluated at mean 9.2 weeks. The mean operative time was 34 minutes. The procedure was very gentle, all patients tolerated it well and there was no bleeding. Most patients experienced some dysuria for three to four weeks after the procedure, two had severe symptoms. Two patients remained in retention and required transurethral resection. The rest expressed subjective satisfaction with the results. Peak urinary flow increased from mean 9.0 ml/sec preoperatively to 15.4 ml/sec; a mean increase of 78%. One patient developed clinical urinary tract infection. There were no other complications of clinical significance.

A new system for descriptive classification of stones in the upper urinary tract.

A descriptive classification is proposed to stratify upper urinary tract stones by their number, size and location. The system considers the minimal but most important factors regarding the choice of surgical treatment and its success. Its principle is adaptable to more complex staging systems already existing. Practical use of the system has shown it to reflect clinical events, and its simplicity offers an opportunity for compliance in routine clinical study. It facilitates easy computerized stratification of stones in the upper urinary tract.

Does the administration of systemic radiographic contrast media influence the acute changes in renal physiology following exposure to extracorporeal shock waves in dogs?

Five anesthetized dogs were studied for 4 to 5 hours after administration of extracorporeal shock waves to one kidney, the contralateral organ serving as control. Repetitive major doses of the nonionic monomeric radiographic contrast medium (CM) iohexol were injected intravascularly before and after application of the extracorporeal shock waves for further provocation of kidney function. Urinary excretion of electrolytes, N-acetyl-beta-glucosaminidase (NAG) and kallikrein, clearances of creatinine, inulin and para-amino-hippuric acid (PAH), serum aldosterone level and plasma renin activity (PRA) were determined. On the exposed side there was a significant fall in urinary osmolality. Effective renal plasma flow (ERPF) was reduced and glomerular filtration rate (GFR) was unchanged; thus filtration fraction (FF) was increased. Extraction of PAH was reduced, and true renal plasma flow was unchanged. Urinary osmolality on the control side was unchanged. There was a fall in ERPF and increased GFR; therefore, FF increased. The mean rise of PRA in the exposed kidney was significant after shock waves. Urine volume and urinary excretion of electrolytes and kallikrein were stable bilaterally. Relating the results to those obtained in identical canine experiments without CM, simultaneous administration of CM does not seem to significantly influence the changes in kidney function parameters caused by extracorporeal shock waves in the dog.

Absence of activation of proteolytic enzymes by extracorporeal shock waves.

The mechanism of tissue damage by extracorporeal shock wave lithotripsy has not been clarified, but proteolytic enzymes are known to play an important role in tissue breakdown in response to other types of injury. Screening tests for activation of the proteolytic enzymes kallikrein, plasmin, trypsins 1 and 2, and granulocyte elastase therefore were performed for 4 to 5 hours in 14 dogs after unilateral treatment with 1500 or 2000 extracorporeal shock waves under anesthesia and vigorous hydration. We also studied the activity of the proenzymes prekallikrein, plasminogen, and prothrombin and three plasma protease inhibitors (kallikrein inhibitor, antiplasmin, and antithrombin III). Blood from both renal veins (treated and control kidneys) and the aorta and tissue samples of the injured renal parenchyma and corresponding areas of the control kidneys revealed no proteolytic enzyme activation by the shock waves and no decline in the activities of proenzymes and enzymes inhibitors. Significant proteolysis does not seem to play a part in the tissue injury induced by extracorporeal shock wave lithotripsy.

Acute changes in kidney function following extracorporeal shock wave lithotripsy for renal stones.

Seventeen patients were subjected to analysis of various renal functional parameters before and after extracorporeal shock wave lithotripsy (ESWL) for renal stones. Thirteen patients were observed at 2 weeks and 3 months. Glomerular filtration rate (GFR) was not influenced by ESWL as based on unchanged serum levels of creatinine, beta 2-microglobulin and creatinine clearance. A significant increase in urinary excretion of beta 2-microglobulin, N-acetyl-beta-glucosaminidase and alkaline phosphatase, with return to pre-treatment values within 4 to 5 days, reflected transient disturbances in proximal tubular function. Urinary albumin excretion was increased 0-24 h after ESWL. No significant alterations were observed in plasma renin activity or serum aldosterone due to ESWL. Serum lactic dehydrogenase remained significantly increased for 2 weeks. In addition, significant changes in several blood and urine parameters were caused by immersion in water and intravenous infusions during treatment and were not specifically due to ESWL.

Acute changes in renal function following extracorporeal shock wave lithotripsy in patients with a solitary functioning kidney.

Twelve consecutive patients with a solitary functioning kidney were treated for renal stone by extracorporeal shock wave lithotripsy (ESWL*) with the modified Dornier HM3 lithotriptor and studied for 3 days after treatment. Urinary excretion of electrolytes, N-acetyl-beta-glucosaminidase (NAG), alkaline phosphatase, kallikrein, glycosaminoglycans, albumin and beta 2-microglobulin, and clearances of creatinine, inulin and para-aminohippuric acid were determined, as were serum levels of creatinine, urea, beta 2-microglobulin and aldosterone, and plasma renin activity. Urinary flow rate, free water clearance, and urinary excretion of NAG, kallikrein and beta 2-microglobulin were significantly increased 0 to 24 hours after ESWL. The urinary excretions of alkaline phosphatase, albumin and glycosaminoglycans were unchanged. Glomerular filtration rate was significantly decreased and effective renal plasma flow was unchanged. Filtration fraction was stable. Serum lactic dehydrogenase increased significantly after ESWL and remained high through the period of observation. Serum levels of creatinine, beta 2-microglobulin and aldosterone were unaltered. A decrease in plasma renin activity immediately after treatment is explained by the water immersion and the extracellular volume expansion during treatment.

Do extracorporeal shock waves affect urinary excretion of glycosaminoglycans?

Urinary excretion of glycosaminoglycans (GAGs) was studied in 9 anaesthetised dogs and 10 patients with single kidneys. The animals were studied for 4 to 5 hours after administration of shock waves to 1 kidney, the contralateral organ serving as control. Urinary excretion of GAGs was measured on both sides. The patients were studied 0 to 24 and 32 to 56 h after extracorporeal shock wave lithotripsy (ESWL). In the animals an increased mean urinary excretion of GAGs was observed on both sides; this was more marked in the treated kidney. The increase reflects tissue injury in the exposed kidney induced by the extracorporeal shock waves. No increase in mean urinary excretion of GAGs was observed in the patients.

Acute morphological changes in canine kidneys after exposure to extracorporeal shock waves. A light and electron microscopic study.

The acute effects of extracorporeal shock waves on renal morphology were studied by light and electron microscopy in 14 dogs. One kidney received an average clinical number of exposures, the nonexposed, contralateral kidney serving as control. The original Dornier HM-3 generator was used in 3 animals, the modified version in 11. Intravascular radiographic contrast medium was administered in five animals. Damage was observed in all exposed kidneys, none in the contralateral control kidney. The effects were characterized by renal and perirenal hemorrhage and edema, parenchymal hemorrhagic foci with tissue destruction, often extending from cortex to medulla. In the nearby regions there was endothelial cell damage in arteries, veins and glomerular capillaries. Breaks in the wall of these vessels were detected with platelet plug formations and thrombi. In glomeruli, breaks of Bowman's capsule and epithelial cell damage with loss of foot processes were observed. A wide range of tubular cell damage was demonstrated, ranging from vacuolization to complete necrosis. Tubular lumina were filled with red cells, indicating renal origin of hematuria. The tissue damage was less pronounced in kidneys exposed to the modified lithotriptor than to the original. No difference in the quantity or quality of damage was detected whether radiographic contrast medium was administered or not.

Acute physiological changes in canine kidneys following exposure to extracorporeal shock waves.

Nine anesthetized dogs were studied for four to five hours after administration of extracorporeal shock waves to one kidney, the contralateral organ serving as control. Urinary excretion of electrolytes, N-acetyl-beta-glucosaminidase (NAG) and kallikrein, clearances of creatinine, inulin and para-amino-hippuric acid (PAH), serum aldosterone level and plasma renin activity (PRA) were determined. On the exposed side there was a significant increase in urinary flow and urinary NAG excretion, and a significant fall in urinary osmolality. Effective renal plasma flow (ERPF) was reduced and glomerular filtration rate (GFR) unchanged, thus filtration fraction (FF) was increased. Extraction of PAH was significantly reduced compared with the control kidney. On the control side there was a significant increase in urinary flow and excretion of electrolytes, and a significant fall in urinary osmolality. GFR was increased and ERPF unchanged. FF therefore increased also on this side. The mean rise of PRA in the exposed kidney was higher than in the control kidney, the difference being not significant (p = 0.09). Our results may indicate a triggering of the renin-angiotensin system, and an effect on proximal tubular function following exposure of extracorporeal shock waves.