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The aim of this article is to review the magnetic resonance (MR) findings of pelvic floor descent and pelvic organ prolapse in women. In addition, a detailed grading system of pelvic organ prolapse and pelvic floor relaxation based on dynamic MR imaging is presented. The technique described here uses very fast MR sequences, is reproducible and easily learned by radiologists and technologists, is well accepted by patients, and provides as much information as traditional projectional X-ray imaging. Reference points are the pubococcygeal line and puborectalis muscle sling. The grading system is based on degree of organ prolapse through the hiatus and the degree of puborectalis descent and hiatal enlargement.

Purpose: We assessed the merit of dynamic half Fourier acquisition, single shot turbo spin-echo sequence T2-weighted magnetic resonance imaging (MRI) for evaluating pelvic organ prolapse and all other female pelvic pathology by prospectively correlating clinical with imaging findings., Materials and Methods: From September 1997 to April 1998, 100 consecutive women 23 to 88 years old with (65) and without (35) pelvic organ prolapse underwent half Fourier acquisition, single shot turbo spin-echo sequence dynamic pelvic T2-weighted MRI at our institution using a 1.5 Tesla magnet with phased array coils. Mid sagittal and parasagittal views with the patient supine, relaxed and straining were obtained using no pre-examination preparation or instrumentation. We evaluated the anterior vaginal wall, bladder, urethra, posterior vaginal wall, rectum, pelvic floor musculature, perineum, uterus, vaginal cuff, ovaries, ureters and intraperitoneal organs for all pathological conditions, including pelvic prolapse. Patients underwent a prospective physical examination performed by a female urologist, and an experienced radiologist blinded to pre-imaging clinical findings interpreted all studies. Physical examination, MRI and intraoperative findings were statistically correlated., Results: Total image acquisition time was 2.5 minutes, room time 10 minutes and cost American $540. Half Fourier acquisition, single shot turbo spin-echo T2-weighted MRI revealed pathological entities other than pelvic prolapse in 55 cases, including uterine fibroids in 11, ovarian cysts in 9, bilateral ureteronephrosis in 3, nabothian cyst in 7, Bartholin's gland cyst in 4, urethral diverticulum in 3, polytetrafluoroethylene graft abscess in 3, bladder diverticulum in 2, sacral spinal abnormalities in 2, bladder tumor in 1, sigmoid diverticulosis in 1 and other in 9. Intraoperative findings were considered the gold standard against which physical examination and MRI were compared. Using these criteria the sensitivity, specificity and positive predictive value of MRI were 100%, 83% and 97% for cystocele; 100%, 75% and 94% for urethrocele; 100%, 54% and 33% for vaginal vault prolapse; 83%, 100% and 100% for uterine prolapse; 87%, 80% and 91% for enterocele; and 76%, 50% and 96% for rectocele., Conclusions: Dynamic half Fourier acquisition, single shot turbo spin-echo MRI appears to be an important adjunct in the comprehensive evaluation of the female pelvis. Except for rectocele, pelvic floor prolapse is accurately staged and pelvic organ pathology reliably detected. The technique is rapid, noninvasive and cost-effective, and it allows the clinician to visualize the whole pelvis using a single dynamic study that provides superb anatomical detail.

Objectives: With significant vaginal prolapse, it is often difficult to differentiate among cystocele, enterocele, and high rectocele by physical examination alone. Our group has previously demonstrated the utility of magnetic resonance imaging (MRI) for evaluating pelvic prolapse. We describe a simple objective grading system for quantifying pelvic floor relaxation and prolapse., Methods: One hundred sixty-four consecutive women presenting with pelvic pain (n = 39) or organ prolapse (n = 125) underwent dynamic MRI. The "H-line" (levator hiatus) measures the distance from the pubis to the posterior anal canal. The "M-line" (muscular pelvic floor relaxation) measures the descent of the levator plate from the pubococcygeal line. The "O" classification (organ prolapse) characterizes the degree of visceral prolapse beyond the H-line., Results: The image acquisition time was 2.5 minutes per study. Each study cost $540. In the pain group, the H-line averaged 5.2 +/- 1.1 cm versus 7.5 +/- 1.5 cm in the prolapse group (P <0.001). The M-line averaged 1.9 +/- 1.2 cm in the pain group versus 4.1 +/- 1.5 cm in the prolapse group (P <0.001). Incidental pelvic pathologic features were commonly noted, including uterine fibroids, ovarian cysts, hydroureter, urethral diverticula, and foreign body., Conclusions: The HMO classification provides a straightforward and reproducible method for staging and quantifying pelvic floor relaxation and visceral prolapse. Dynamic MRI requires no patient preparation and is ideal for the objective evaluation and follow-up of patients with pelvic prolapse and pelvic floor relaxation. MRI obviates the need for cystourethrography, pelvic ultrasound, or intravenous urography and has become the study of choice at our institution for evaluating the female pelvis.

Objective: The purpose of this paper is to present our experience with CT- and fluoroscopy-guided percutaneous nephrostomy tube (PNT) placement and to describe the technique of placement with patients in the supine-oblique position., Materials and Methods: A CT scanner was coupled with a ceiling-mounted C-arm for fluoroscopy at the CT table, PNT was done with CT localization and fluoroscopic control. We attempted 148 placements in 129 patients, with most patients in the supine or the supine-oblique position., Results: Successful PNT placement was achieved in 144 (97%) of 148 kidneys. In the native kidney group, 101 (81%) of 124 PNTs were placed with the patients in the supine-oblique position. We experienced no major complications, three (2%) minor complications, and two (1%) catheter dislodgments., Conclusion: CT-fluoroscopy control allows routine PNT placement with patients in the supine or the supine-oblique position and is associated with the lowest complication rate to our knowledge.

In detection and work-up of a renal carcinoma, imaging plays the most critical role. Differentiation of renal cell carcinoma from angiomyolipoma and complex cysts is highly accurate, but differentiation from benign oncocytoma is not. The most important discoveries regarding local staging are presence of venous tumor thrombus and its cephalad extension, followed by regional lymph node metastases. Biopsy of a renal mass is indicated when a concomitant primary malignancy is present elsewhere, but only if treatment will be influenced by findings. Preoperative embolization is reserved for the most difficult cases, and palliative embolization is useful in selected cases. Helical computed tomography is the most sensitive method for detecting small lung metastases.

We investigated a catheter that can longitudinally incise ureteral strictures under fluoroscopic guidance without the need for ureteroscopy and its attendant risks. The catheter consists of a low-pressure balloon and an overlying cautery wire; the balloon allows precise localization of the stricture, seen as a waist in the balloon, and the overlying cautery wire can be fluoroscopically oriented at the stricture. One to two centimeter ureteral strictures were created in 6 swine. Two to four weeks later strictures were incised in a retrograde or antegrade fashion with the cautery-wire balloon catheter, and double J stents placed for a duration of three weeks. In 5 of 6 renal units strictures improved anatomically with resolution of hydronephrosis at 3 to 4 months' follow-up. Urodynamic absence of obstruction was verified by Whitaker testing. In one animal, the tip of the catheter dislodged in the ureter with subsequent loss of the renal unit. The engineering error that lead to this complication has since been rectified. With correction of the aforementioned problem, this Phase 1 study has demonstrated the feasibility, safety and preliminary efficacy of the cautery-wire balloon catheter for endourologic management of ureteral strictures.

The authors report their experience with 56 percutaneous nephrostomies (PCNs) performed on an outpatient basis on 55 patients. Complications included pain that required use of parenteral medication in four patients, bleeding in three that resolved spontaneously, and shaking chills or fever in 12. This last complication, considered to be a sign of sepsis and treated with antibiotics, occurred more frequently than the 1.4%-4.5% infectious complication rate reported in the literature. Antibiotic use during and after PCN significantly decreased the likelihood of sepsis. In the high-risk group, antibiotic administration during and after PCN decreased the risk of developing signs of sepsis from 50% to 9%. On the basis of the authors' results and the findings in the literature about antibiotic prophylaxis, guidelines are recommended to improve the safety of PCN as an outpatient procedure. In the majority of instances PCN should still be considered to be more safely performed as an inpatient procedure at this time.

Percutaneous interventional procedures can be valuable in the evaluation and treatment of urologic complications of renal transplantation. Thirty-three patients underwent percutaneous procedures, including relief of obstruction by catheter nephrostomy, diagnostic antegrade pyelography with Whitaker testing, aspiration of various fluid collections (lymphocele, hematoma, urinoma, and abscess), and renal artery angioplasty, during a three year period at three institutions, to provide temporizing treatment and anatomic data. Surgical intervention was sometimes avoided, but more often it could be deferred to allow the patient to stabilize prior to surgery. Complications that required surgery occurred in two patients.

Thirty-five patients with high blood pressure underwent digital intravenous subtraction angiography (DSA) for evaluation of renovascular disease. Eight had recurrent hypertension after renal transplantation, and four after aortorenal bypass. Twenty-three had DSA as part of a hypertensive screening workup for renovascular disease. Diagnostic studies were obtained in 33 patients. Twelve patients had confirmatory arteriograms and agreement occurred in 10. DSA detected significant pathology in nine of the post-renal-surgery patients. DSA followed by a minimal number of overhead abdominal films to evaluate the renal parenchyma, ureters, and bladder was found to be a preferable alternative to the conventional rapid-sequence excretory urogram as a screening test for patients with suspected renovascular disease.

A spectrum of rare urachal abnormalities in the adult is described, including urachal cyst, infected urachal cyst and abscess, and urachal carcinoma. The clinical and radiographic features are presented, and diagnosis using ultrasound, computed tomography, and needle aspiration is discussed. Treatment of infected urachal cysts with percutaneous catheter drainage is described.

A large field format imaging system which utilizes a flat fluorescent screen rather than the traditional image intensifier as the primary x-ray detector is discussed in this paper. A low light level image isocon camera is optically coupled to a rare-earth screen. An overview of the isocon camera and its return beam mode of operation is included. Theoretical limitations to this approach to real time radiographic imaging are discussed in terms of system efficiency and signal-to-noise ratio (SNR) requirements. The viability of this concept for radiographic imaging is considered with respect to the image intensifier-camera unit. The merits of employing a CsI:Na screen as the primary detector and an isocon tube with an improved SNR are presented as potential areas for further investigation.

Transcatheter arterial embolization is becoming an accepted method of controlling massive acute hemorrhage, including that secondary to blunt and penetrating renal trauma. Two patients with retroperitoneal bleeding postrenal biopsy and angiographically proved pseudoaneurysms at the biopsy sites had successful embolization without sequelae. Experimental and clinical experience with transcatheter embolization is reviewed. It appears that this modality is a safe, effective way of controlling renal hemorrhage.

Percutaneous nephrostomy is a very valuable radiologic procedure for providing temporary or permanent urinary diversion of an obstructed upper urinary tract. While changes in catheter and guide wire technology have allowed for marked enhancement of the indications for percutaneous nephrostomy, the classic indications remain, such as decompression in patients with urosepsis and azotemia, especially with concomitant medical problems that require time to bring under control.

Percutaneous transperitoneal fine-needle lymph-node biopsy was performed in 52 patients to establish a diagnosis of metastatic disease in nodal defects detected during lymphography. The procedure was found to be highly accurate, with few false-negatives and no false-positives.

An anterior transperitoneal incision was used to remove stones from 20 kidneys in 18 patients (2 bilateral). Our experience with 35 kidneys operated upon by this method (15 previously reported) has been favorable. Use of percutaneous nephropyelostomy tubes to drain obstructed kidneys in septic patients has permitted all procedures to be done under non-emergency conditions. Careful alignment of x-ray equipment and adjustment of exposure technique in the operating room before induction of anesthesia result in consistently good quality preoperative and intraoperative roentgenograms. The transperitoneal approach has afforded good access to the anterior portion of the renal pelvis even in those patients who have had previous operations on the kidney by the flank approach. Additional intra-abdominal procedures done at the same operation have included urinary diversion by ileal loop, revision of previous ileal loop, ureterolithotomy, pyeloureteroplasty, partial nephrectomy, cholecystectomy and appendectomy. The procedures done with the patients in the supine position have been well tolerated even in patients with serious coincident medical diseases.

In search of a hepatolienographic agent, the iothalamate ethyl ester particulate suspension was prepared with the average particle size of 1.5 mu in diameter. When mixed with plasma of different animal species, the physical properties of the particular suspension changed significantly. The nature of this difference is not understood but is probably related to protein-particle interaction in the different species. Doses of 550 mg iodine per kg body weight as a single intravenous infusion of the particulate suspension resulted in satisfactory opacification of liver and spleen in rats, followed by complete loss of radiopacity within three days. Larger doses resulted in the death of the rats within 12-14 hours. In general, the mice tolerated larger doses than rats, but there was very poor opacification of the liver, despite good opacification of spleen. Further work is being carried out to improve the suspension and to better understand the difference in behavior of the particulate suspension in different animal species.

Nephromegaly associated with hyperalimentation and its effect on renal function were studied. Renal size was determined in 44 patients receiving total parenteral nutrition (TPN). Of 26 patients in whom kidney size could be determined before and during TPN, all but one had normal-size kidneys before TPN. Six had no increase in renal size, and kidneys increased in size in 20. One or both kidneys became abnormally large in 9 patients. There was no detectable change in renal function and kidneys decreased in size upon discontinuation of hyperalimentation. Abnormal renal size bore no relation with weight gain or liver function tests.

Through an artificially created ureteral obstruction in the dog, a ureteral stent was placed with the aid of a percutaneous nephrostomy tube. The stent was removed after two weeks. This resulted in permanent relief of the obstruction in the treated animals. In contrast to this, the control animals remained completely obstructed with resultant hydronephrosis and loss of kidney. It is proposed that this method can be used in humans where nephropyelostomy had been placed and where surgical correction of the obstructed ureter is not feasible.

A new radiological sign is described consisting of opacification of the pelvocalyceal wall during the early stage of an excretory urogram. This sign is associated with acute infection in an obstructed urinary tract system.

The incidence and cause of urinary tract obstruction in 100 consecutive patients with polycystic renal disease are reported. Because of nonspecific symptoms, poor renal function, and calyceal distortion, obstruction may be difficult to detect. A number of patients had infundibular obstruction caused by a calculus, clot, or inflammation and edema of the pelvocalyceal wall.

Emergency temporary percutaneous nephrophelostomy was performed 35 times in 34 patients. This procedure was used to relieve urinary tract obstruction when azotemia, infection, sepsis, or associated medical conditions precluded surgical correction of a renal obstruction. In all patients there was excellent clinical response. Supine oblique positioning in ill patients facilitates placement of nephrophelostomy tubes.

A new system for digital vascular subtraction imaging is presented. The image receptor consists of a rare-earth screen with light output optically focused onto the photocathode of a low-light-level image Isocon camera. This system represents a departure from the conventional use of the image intensifier for digital subtraction imaging. Our initial results suggest that this system could be competitive with traditional image intensifier systems and that it deserves clinical trial.

The anatomy and radiographic appearance of five types of augmentation enterocystoplasty (ileocystoplasty, cecocystoplasty, ileocecocystoplasty, sigmoidocystoplasty, and enterourethroplasty) are described. Retrograde cystrography is the procedure of choice for optimal visualization of an augmented bladder and most complications. Excretory urography is useful for following concurrent upper tract disease and ureteral stenosis. Critical factors in a optimal examination are maximal filling of the bladder and radiographs in multiple projections.

A new method for arresting uncontrollable intercostal hemorrhage is presented. It consists of selective transcatheter embolization of the bleeding artery, either by pieces of gel foam or autologous blood clots. In the patient presented in this paper, the hemorrhage was identified and successfully controlled by embolizing the bleeding artery. Thoracotomy was unnecessary, and there were no complications related to the procedure.

Percutaneous transperitoneal fine needle biopsy is a harmless, easy to perform, and most direct procedure used to diagnose uncertain causes of ureteral obstruction and displacement of various parts of the urinary tract system. Frequently it is the least invasive method that can decide further treatment.

Image opacification, patients' tolerance, and clinical and laboratory findings were evaluated in patients having excretory urography at three centers. In a double-blind, parallel study, iopamidol was compared with diatrizoate (50-ml dose), and in an open-label trial, the administration of a 100-ml dose of iopamidol was evaluated. In the double-blind study, a total of 84 patients received 50 ml of either iopamidol or diatrizoate. In the open-label study, another 42 patients received a 100-ml dose of iopamidol. Image opacification scores after the administration of the 50-ml doses showed better opacification with iopamidol than with diatrizoate in the renal calices (p less than .05) and in the composite kidney (p less than .05). Opacification scores were higher for 100-ml doses of iopamidol than for 50-ml doses in all anatomic regions as well as in the composite kidney (p = .0001). Patients' tolerance to iopamidol was significantly better than their tolerance to diatrizoate (p less than .025). Investigators observed adverse drug reactions in a total of 10 patients. In the double-blind study, one of 43 patients had transient bradycardia after the administration of iopamidol. In the same study, four of 41 patients who received diatrizoate had five minor adverse drug reactions. With 100-ml doses of iopamidol, five of 42 patients had adverse reactions. No adverse side effects required therapy in either study. There were no significant changes in vital signs or laboratory values after drug administration. The results of this study show that iopamidol is a suitable agent for excretory urography at doses of 50 and 100 ml. Patients report fewer unpleasant side effects with iopamidol than with diatrizoate. Overall image quality was better with iopamidol than with diatrizoate. Overall evaluation of drug performance was better with iopamidol than with diatrizoate.

Two patients are described who presented with complete urinary obstruction secondary to nonopaque uric acid stones. They were treated with percutaneous nephrostomy for urinary diversion and urinary alkalinization by local irrigation and oral sodium bicarbonate therapy with complete dissolution of the stone after 16 and 21 days of therapy. Percutaneous nephrostomy with urinary alkalinization is a reasonable, relatively safe alternative to surgical stone removal for patients with obstructing uric acid stones.

Ten cases of multiple ureteral diverticula are presented. Microscopic correlation was available in 5. Associated findings included urinary stones, obstruction, infection, and transitional-cell carcinoma. Such diverticula are one manifestation of epithelial hyperplasia, more commonly seen as ureteritis cystica.

Thirty-two patients with inadvertent intraoperative ureteral trauma or ligation are presented. One-third of the injuries were due to general surgical procedures such as lumbar sympathectomy, aortoiliac bypass and colectomy. Because of postoperative pain, discomfort and sedation, these injuries are frequently unrecognized for long periods. This delay in diagnosis results in significant morbidity and mortality. The usual radiologic approach is an excretory urogram supplemented if necessary by a retrograde pyelogram. Temporary percutaneous or operative nephropyelostomies have been employed in seven of these patients.

The American Medical Systems' inflatable anti-incontinence device is a relatively new prosthesis. Its design, function, and proper method of radiographic evaluation in the pre- and postoperative patient are discussed. Complications peculiar to this device are demonstrated.

The improved appearance of digital radiographs filtered to improve local contrast and sharpen edges has not increased acceptance of these images by radiologists. Furthermore, many radiologists assert that correct diagnosis is not improved with these filtered images. This study was designed to test this assertion for digital subtraction angiograms (DSA) of renal images. Four experiments are described. First, phantom studies identified filters and their parameters thought likely to be acceptable and useful in diagnosing renal images formed by DSA. Second, these filters and parameters were then tested on medical images to assess their acceptance by radiologists. Third, display modes of windowing, positive/negative presentation, and magnification were varied for filtered and unfiltered images to assess preferences of radiologists. Fourth, filtered and unfiltered magnified images were used to test improved diagnosis. In the final experiment, 148 images from 33 renal studies (15 normal, 18 abnormal) were magnified, gray level windowed, and filtered. Diagnosis was not improved by the two edge sharpening filters tested.

Extracorporeal shock wave lithotripsy (ESWL) was performed on 925 patients (1,222 treatments) for 446 calyceal, 345 pelvic, 172 ureteral, and 108 staghorn calculi. ESWL necessitated 6.3 KUB and 1.2 renal ultrasound studies per treatment session. Intravenous urography was required in 6% of patients after ESWL. Percutaneous nephrostomy tube placement was performed by the radiologists in 10% of patients. Procedures related to nephrostomy tube placement included percutaneous nephrolithotripsy, tube changes, nephrostography, and stone fragment irrigations and retrievals. Staghorn calculi treatment with ESWL required the most procedures by radiologists (34% for partial staghorn and 56% for complete staghorn) compared with 3%, 8%, and 11% for calyceal, pelvic, and ureteral stones, respectively. In all, 8,478 radiologic examinations and procedures were performed pertaining to ESWL. This is approximately 35 studies per day. While this number may be high because it represents the early experience of the authors with ESWL, the impact on the radiology department can be substantial.

The use of percutaneous nephrostomies (PCNs) in 1456 patients (1660 kidneys) treated with extracorporeal shock-wave lithotripsy (ESWL) was evaluated. In this group, 138 PCNs (130 patients) were performed in 133 kidneys. Forty-seven percent of PCNs were placed in patients with staghorn calculi; 24% were for stones in the renal pelvis, and 20% for ureteral stones. The most common indication for PCN was fever and obstruction (57%). In 15%, the indications were failure to decompress an obstructed system from a retrograde direction, clogged double-J ureteral stents, and perforation of the ureter. Prophylactic PCN placement in the treatment of staghorn calculi and large stones in the renal pelvis accounted for 12%. Five percent were placed for miscellaneous other reasons, and for 11% there was no documentation of the indication because they were placed before the patients came to our center. Localization of the collecting system for optimal placement of PCN is unique in ESWL patients because the residual stone fragments provide natural contrast. This eliminates the need for administration of contrast material in 50% of the patients. Twenty-six percent of PCN tracts were subsequently used for other procedures (e.g., percutaneous nephrolithotomy, fragment irrigation, ureteral stone manipulation). Bleeding complications from PCN occurred in 7%. Other minor complications occurred in 12% of cases. PCN is a useful adjuvant to ESWL treatment of kidney stones. Although its major use is to relieve urinary tract obstruction, it is also used as a preliminary step in planning other percutaneous interventional procedures. This is particularly the case in the treatment of large bulky stones in the renal pelvis and staghorn calculi.

Thermo-magnetic surgery is an innovative modality in the treatment of malignancies. This unique combination can produce selectively controlled destruction of deep tumors. Heating of the magnetic metallic compounds of ferrosilicone by hysteresis produces temperatures which are incompatible with cancer cell survival. The intense focal heating causes a coagulation necrosis. Damage to surrounding normal tissue can be avoided by careful temperature monitoring and power control of the magnetic field. Cell destruction in the target tissue has been demonstrated by light and electron microscopy. Reproducible and predictable VX2 renal carcinomas in rabbits have been produced and used as the tumor model in the initial experiments of this research project. A clinical trial with selected cancer patients, performed with this technique of thermo-magnetic surgery, is now a reasonable and feasible procedure.

A new imaging system for digital subtraction angiography (DSA) was evaluated in 30 clinical studies. The image receptor is a 25 X 25 cm, 12 par gadolinium oxysulfate rare-earth screen whose light output is focused to a low-light-level Isocon camera. The video signal is digitized and processed by an image-array processor containing 31 512 X 512 memories 8 bits deep. In most patients, intraarterial DSA studies were done in conjunction with conventional arteriography. In these arterial studies, images adequate to make a specific diagnosis were obtained using half the radiation dose and half the amount of contrast material needed for conventional angiography. In eight intravenous studies performed either to identify renal artery stenosis or for evaluation of congenital heart anomalies, the images were diagnostic but objectionably noisy.

Herein we review 100 cases of adult polycystic kidney disease. Flank pain was the most common presentation in these cases. In 20% of the patients calculi were noted and 10% had obstruction. The average patient age at death was 57 years. The importance of tomography is emphasized with key radiographic features, such as bilateral large kidneys, inhomogeneous nephrogram, caliceal distortion and poorly defined renal margins. Cystic involvement of the liver and spleen may help to confirm the diagnosis. Differential diagnosis includes bilateral multiple simple cysts, angiomyolipomatosis and bilateral renal carcinomas.

Autonomic dysteflexia is a pathologic reflex which occurs in patients with a spinal cord lesion above T7. The most dangerous manifestation of this reflex is marked increase in systolic and diastolic blood pressure. The trigger is the distension of the urinary bladder, urethra, rectum, or intestine. It can and does occur during radiological examinations such as cystourethrography, loopography, and probably during the barium enema. Because of possible deleterious consequences of marked hypertension, blood pressures in these patients should be continuously monitored during the examinations and appropriate measures immediately instituted should the reaction occur.

Uroradiological examinations on 33 patients subjected to abdomino-perineal resection were analyzed. The most common finding was medial displacement of both ureters, with the right one frequently crossing the midline. Bladder deformity, sometimes severe, was present in all patients. Localized ureteral narrowing due to stricture or recurring neoplasm was found in 30% of the patients examined. Other common complications included retrovesical abscesses, periurethral abscesses, urethral fistulas and strictures, and bladder retention. All these findings were more prominent in men.

In support of the thesis that MRI may replace more invasive angiography in some applications, a total of 28 MR sections are presented to illustrate the vascular anatomy of the abdomen in coronal, transverse and sagittal planes. More than 20 vessels are identified ranging in size from the aorta to the left inferior adrenal vein and the spermatic veins. There is no anatomic continuity in sections made in the coronal and transverse planes; sequential sections of a single patient are presented in sagittal and parasagittal planes, however. The polarity of the images is reversed for ease of comparison with angiograms.

Angiography and nephroangiography has been performed 3 and 6--10 weeks after induced trauma to 18 rabbit kidneys. The lesions, mimicking crush trauma or surgical ectomy, were repaired using a cyano-acrylate. Perinephric tissue was adhered to the wound and made repair easier in crush trauma. In the resected kidneys it constituted a new pelvic wall. The angiographies demonstrated that in essence only the directly traumatized arteries were abnormal, that the cortical lesions were very small and the venous drainage unimpaired. The function, assessed on urograms, was good. No ureteric obstruction was present.

Percutaneous nephrostolithotomy has proved to be a safe and effective approach to the management of upper tract calculi, which is associated with a low rate of significant complications. Bowel perforation is an unusual complication of this technique. We report a case of a nephrocolic fistula following percutaneous nephrostolithotomy, and discuss the diagnosis and management of this rare complication.

Five percutaneous nephropyelostomies were performed on 4 patients with obstructed renal allografts. In all instances the procedure significantly influenced further management of these patients. It allowed pressure measurement within the obstructed collecting system, assessment of renal function after prolonged drainage, and anatomical delineation of the site of the obstruction using antegrade pyelography. Percutaneous pyelonephrostomy and drainage is a useful means to determine whether obstruction or rejection is the major contributor to renal failure following renal transplantation.

The relatively common occurrence of ureteral obstruction in patients with known malignancy elsewhere presents an interesting clinical problem. In those who have undergone abdominal surgery or radiation therapy for malignancy, it is difficult to determine whether ureteral obstruction is the complication of therapy or of recurrent metastatic carcinoma. Transperitoneal thin-needle aspiration biopsy provides an acceptable alternative in determining the true cause of the obstruction. This procedure is competitive with explorative surgery and laparoscopy and is much more specific than CT, excretory urography, and other imaging modalities. In our series of 32 patients, biopsy revealed metastatic tumor in 18 patients, thus altering their clinical management.

Percutaneous nephropyelostomy using the posterolateral approach was employed together with antibiotics and other supportive therapy as the initial step in the treatment of acute pyohydronephrosis, with gratifying results. Percutaneous nephropyelostomy is recommended as the procedure of choice for this specific clinical emergency.