Evaluation of renal resistive index, maximum velocity, and mean arterial flow velocity in a hydronephrotic partially obstructed pig model.

RATIONALE AND OBJECTIVES: The authors investigate, in a controlled pig model, the usefulness of Doppler sonographic measurements of resistive index (RI), maximum velocity (Vmax), and mean velocity (Vmean) in diagnostic evaluation of the partially obstructed kidney. METHODS: Seven female pigs underwent surgical partial unilateral renal obstruction at the ureteropelvic junction. Doppler parameters of RI, Vmax, and Vmean were measured preoperatively and postoperatively in obstructed and contralateral nonobstructed kidneys. The General Linear Model multivariate analysis of variance was used for statistical analysis of data. RESULTS: There was no significant difference in the preoperative control values of RI (P = 0.71), Vmax (P = 0.27), and Vmean (P = 0.12). There was a statistically significant decrease in the Vmax and Vmean after postoperative day 5 in the obstructed kidney compared with the contralateral nonobstructed kidney (P = 0.01 and 0.03, respectively). There was no statistically significant difference in RI during the study. CONCLUSIONS: In this study, RI was not a reliable indicator of partial renal obstruction. Measurements of maximal and mean blood flow velocities reached discriminatory significance only after the fifth postobstructive day, proving insensitive in the immediate postobstructive period. Vmax and Vmean demonstrated a decrease in the partially obstructed renal collecting system after 5 days of obstruction and may serve as useful parameters in the evaluation of obstruction after the immediate acute period, when compared with a nonobstructed contralateral system.

Diphtheria corneal ulcers.

An adult with cutaneous diphtheria was admitted with bilateral purulent conjunctivitis and a perforated eye with most of the cornea absent due to Corynebacterium diphtheriae. At the time of admission of grayish patch of corneal epithelium was noted in the other eye, and in the next 24 hours there developed a large corneal perforation with dissolution of much of the cornea. Involvement of the external eye in diphtheria is rare but it is usually associated with cutaneous forms of the disease. Cutaneous diphtheria has been prominent in several recent outbreaks in the United States. Prompt recognition, early antibiotic treatment, and neutralization of the toxin with antitoxin are required for successful therapy.

Pleural effusion secondary to ureteral obstruction.

Urinary tract obstruction may produce a pleural effusion detectable by chest x-ray film. This uncommon finding must be differentiated from intrathoracic and intraperitoneal causes of pleural effusion, including intrathoracic metastases when a malignant tumor is the cause of the urinary tract obstruction.

Invasive bladder carcinoma treated by radical cystectomy: survival of patients.

Sixty-three patients underwent radical cystectomy for invasive bladder carcinoma at West Virginia University Medical Center from 1961 to 1978. Survival statistics are presented and discussed in comparison with alternative modes of therapy. A brief discussion of complications is also presented.

Genitourinary leiomyomas.

Leiomyomas may originate from any anatomic location of smooth muscle in the genitourinary system but are uncommon neoplasms. Five unusual cases of leiomyomas arising from the renal pelvis, bladder, spermatic cord, and glans penis are presented. The leiomyoma arising from the glans penis in a three-year-old boy is the first case of a leiomyoma in that location noted in the literature. A review of leiomyomas from each genitourinary structure of origin is presented.

Intrapelvic pressure monitoring in the partially obstructed porcine kidney.

OBJECTIVES: The diagnosis of urinary obstruction in newborns and infants remains difficult because the diagnostic studies available at present are fraught with many problems. It is our premise that precise measurement of renal pelvic pressures under physiologic conditions in patients with urinary tract dilation will allow diagnosis of obstruction and prediction of further renal damage. This study evaluates an intrapelvic pressure monitoring system. METHODS: Four porcine subjects had partial ureteropelvic junction obstruction created surgically; two subjects were used as controls. Doppler ultrasound and MAG-3 furosemide renography were performed preoperatively and each week pressures were measured with a Millar 5 F solid-state pressure transducer and the analog signals were converted on line to digital information to allow signal processing and later data analysis. Antegrade nephrostograms were obtained at the same sitting and showed that the model remained stable over time. Measurements were obtained at physiologic flow rates as well as at the standard Whitaker infusion rate of 10 cc/min. RESULTS: Thirteen pressure studies were performed on 9 kidneys. Each study was classified as normal (4), partial obstruction (8), or total obstruction (1), based on ultrasound and nephrostogram criteria. The normal units had baseline pressures of 4.12 +/- 0.94 cm water (H2O), which increased to 9.12 +/- 1.38 cm H2O with infusion. In the partially obstructed group, baseline was 16.4 +/- 3.83 cm H2O and increased to 35.3 +/- 15.9 cm H2O with infusion. The kidney with total obstruction showed a baseline pressure of 27 cm H2O, which increased to 68 cm H2O with infusion. These pressure measurements were also compared to furosemide renography. CONCLUSIONS: Intrapelvic pressures correlated well with conventional ultrasound and nephrostogram in the evaluation of partial obstruction. However, the results of furosemide renography and the Whitaker test were quite variable and did not accurately define partial obstruction or correlate with intrapelvic pressure. The Millar solid-state transducer monitoring system is an accurate method of evaluating the intrapelvic pressure and could possibly become a standard for diagnosing significant urinary obstruction against which other studies can be evaluated.

Hypernephroma and associated ureteral involvement.

The propensity of a hypernephroma to invade the renal vein and even the inferior vena cava is widely known. However, in contrast to papillary carcinoma of the kidney, hypernephromas rarely involve the ureter. Review of the English literature reveals 42 reported cases of ureteral involvement. Most represented metastases as opposed to direct, contiguous extension which is extremely rare. C case of hypernephroma with contiguous castlike extension into the ureter without mucosal violation is presented. Mechanisms of ureteral involvement and implications regarding treatment of hypernephromas are discussed.

Tangent screen perimetry using twin test objects.

A T-shaped carrier with twin test objects is an inexpensive efficient visual field screening device which facilitated identification of a nasal steppe, a paracentral scotoma, an enlarged blind spot, an arcuate scotoma, macular sparing, or hemianopic defects.

Long-term corneal retention of a plant foreign body.

A fragment of sunflower stalk had been retained in the cornea of a 71-year-old man for 58 years. During initial healing of the wound, which included formation of a retrocorneal membrane over the foreign body in the anterior chamber, there was probably loss of endothelial cells. This probably predisposed the cornea to the endothelial decompensation that occurred following cataract extraction and implant of an intraocular lens 56 years after the foreign body first appeared in the cornea.

Laser prostatectomy devices and their tissue effects.

Laser systems used for prostatectomy may be right-angle (sidefiring) devices, which are either refractive or reflective, or contact devices. The tissue physics of these systems differ, and as a result, there are very real differences in the optimal exposure techniques. An understanding of the device being used is essential for producing a satisfactory result.