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Biomedical subjects

W H Bush

Publications and source records attributed to W H Bush.

At least 37 records · Page 2Linked to original sources
PubMed1999

Endourological treatment of ureteroenteric strictures: efficacy of Acucise endoureterotomy.

PURPOSE: The Acucise endoureterotomy balloon catheter has proved to be a safe and effective alternative to open surgery for the management of ureteropelvic junction obstruction and benign ureteral stricture disease. The established management of ureteroenteric strictures following urinary diversion is open surgical revision. There are few reports evaluating the efficacy of Acucise endoureterotomy in patients with ureteroenteric strictures. MATERIALS AND METHODS: The Acucise cutting balloon catheter was used to treat 9 patients with 12 ureteroenteric strictures 2 cm. or less in length. Median time from diversion to stricture was 48 months (range 13 to 192). Success was defined as resolution of symptoms and radiographic confirmation of patency. RESULTS: Recurrence of malignancy accounted for failure in 1 patient with bilateral strictures. Of the remaining 10 benign strictures 7 (70%) required open revision or serial stent changes. The remaining 3 strictures in 2 patients have remained patent at 30 and 18 months of followup for a success rate of 30%. There were no perioperative or operative complications. Mean followup was 9 months after Acucise treatment before intervention was necessary. CONCLUSIONS: Acucise endoureterotomy for ureteroenteric strictures following urinary diversion is a low morbidity procedure. Although the success rate is only 30%, Acucise endoureterotomy offers an alternative to immediate open surgical revision.

Adult↗
PubMed1998

Treatment of the adverse effects of contrast media.

Although low-osmolar contrast media are relatively safe, a moderate non-life-threatening reaction requiring some treatment does occur in 0.2-0.4% of patients. A severe life-threatening reaction can be expected in 0.04% of patients. Prompt recognition and treatment are invaluable in blunting the adverse response of a patient to radiographic contrast material and may prevent the reaction from becoming severe or even life-threatening. Radiologists and their staff should review treatment protocols regularly so that each can play his/her role efficiently. Knowledge, training, and preparation are crucial for guaranteeing appropriate and effective therapy in the event of an adverse contrast-related event. On the basis of a review of the literature, we suggest a treatment protocol.

Acidosis, Lactic↗
PubMed1998

Adverse effects of contrast media: incidence, prevention and management.

Although contrast media are relatively well tolerated, a non-life-threatening, moderate reaction requiring some treatment occurs in 1 to 2% of patients receiving ionic high-osmolar contrast media and in 0.2 to 0.4% of patients receiving non-ionic low-osmolar contrast media. Severe, life-threatening reactions can be expected in about 0.2% of patients after injection of ionic high-osmolar and 0.04% after non-ionic low-osmolar contrast media. Prompt recognition and treatment are invaluable in blunting an adverse response of a patient to radiographic contrast material, and may prevent a reaction from becoming severe or even life-threatening. Some reactions can be prevented by pretreatment before administration of contrast media. Knowledge, training and preparation are crucial in guaranteeing appropriate and effective therapy in the event of an adverse contrast-related event. Radiologists and their staff should review treatment protocols regularly so that each can accomplish his or her role efficiently.

Contrast Media↗
PubMed1997

Renal artery origins: location and distribution in the transverse plane at CT.

PURPOSE: To determine the in situ location and distribution of the renal artery origins in the transverse plane with computed tomography (CT). MATERIALS AND METHODS: CT scans of the paired main renal arteries in 200 patients (89 men, 111 women) were retrospectively reviewed. The locations of the renal artery origins, defined on the basis of their optimal profile angles, and the angle between them were measured. The degree of aortic atherosclerosis was graded in 119 of the 200 patients. RESULTS: The origins of 400 paired main renal arteries were identified. A statistically significant difference was found between the average best profile angle on the right (24 degrees [range, 26 degrees-70 degrees]) and that on the left (5 degrees [range, -75 degrees to 38 degrees]) (P < .001). Truly laterally located renal arteries were seen on the right in 11 (5%) of 200 right renal arteries and on the left in 56 (28%) of 200 left renal arteries. One hundred eighty-six (93%) of 200 right ostia and only 40 (20%) of 200 left ostia were in an anterolateral location. One hundred four (52%) of 200 left ostia and three (2%) of 200 right ostia were in a posterolateral location. The prevalence of truly opposite renal arteries was 17%. The average profile angle between the renal artery origins was 161 degrees (range, 72 degrees-225 degrees) and was significantly larger in women (P = .001). No relationship was found between ostial location and patient age or atherosclerotic grade. CONCLUSION: In the transverse plane, the location of the origin of the right renal artery tended to be anterolateral and of the left renal artery tended to be posterolateral or lateral. The variation in location and distribution width was great.

Aortic Diseases↗
PubMed1997

Renal artery origins: best angiographic projection angles.

PURPOSE: To determine the best projection angles for imaging the renal artery origins in profile. MATERIALS AND METHODS: A mathematical model of the anatomy at the renal artery origins in the transverse plane was used to analyze the amount of aortic lumen that projects over the renal artery origins at various projection angles. Computed tomographic (CT) angiographic data about the location of 400 renal artery origins in 200 patients were statistically analyzed. RESULTS: In patients with an abdominal aortic diameter no larger than 3.0 cm, approximately 0.5 mm of the proximal part of the renal artery and origin may be hidden from view if there is a projection error of +/-10 degrees from the ideal image. A combination of anteroposterior and 20 degrees and 40 degrees left anterior oblique projections resulted in a 92% yield of images that adequately profiled the renal artery origins. Right anterior oblique projections resulted in the least useful images. CONCLUSION: An error in projection angle of +/-10 degrees is acceptable for angiographic imaging of the renal artery origins. Patients sex, site of interest (left or right artery), and local diameter of the abdominal aorta are important factors to consider.

Angiography↗
PubMed1995

Determination of serum creatinine level before intravenous administration of iodinated contrast medium. A survey.

RATIONALE AND OBJECTIVES: To study the practice of obtaining serum creatinine before administering intravenous iodinated contrast medium and the costs associated with this practice. MATERIALS AND METHODS: In June 1993, a questionnaire was sent to 217 physicians who are members of the Society of Uroradiology or the Society of Computed Body Tomography/Magnetic Resonance. There were 149 respondents who completed a total of 70 questionnaires, providing a response rate of 69% (149/217). RESULTS: The percentage of institutions that always require a serum creatinine before administering intravenous contrast medium for excretory urography, body computed tomography, and head computed tomography was 13%, 20%, and 14%, respectively. In institutions where routine serum creatinine is not required, approximately 60% request a serum creatinine in either insulin-dependent or juvenile type 1 diabetes. The mean maximal acceptable time between the serum creatinine value and contrast administration is 29 days. It takes a mean of 69 minutes to get the results of a stat serum creatinine and costs a mean of 15 dollars for the test. In patients with no risk factors, the mean for the highest serum creatinine value at which respondents still gave contrast was 2.1 mg/dL; in patients with risk factors, the mean was 1.9 mg/dL. There was no correlation between the use of serum creatinine and the number of studies performed in the institution or the type of contrast used. CONCLUSIONS: The practice of requiring a pretest serum creatinine and its interpretation regarding the use of contrast media are quite variable. In view of this disparity in opinion, development and acceptance of a list of patients who are at increased risk for contrast-induced nephropathy may be desirable.

Acute Kidney Injury↗
PubMed1994

Catheter modification for transrenal temporary total ureteral obstruction: the "occlusive" nephroureteral catheter.

When temporary diversion of urine is desired and a simple nephrostomy catheter is insufficient or passage of a ureteral stent cannot be achieved, a standard 8 or 10 F nephroureteral catheter can be modified to provide a single nephrostomy drainage catheter with an occluded ureteral segment that provides total diversion of urine. The "occlusive" nephroureteral catheter is exchangeable over a guide wire as necessary. When healing of the ureteral or bladder process has occurred, the catheter is removable, allowing restoration of normal urine flow.

Adult↗
PubMed1992

Prolonged continuous intravenous infusion interleukin-2 and lymphokine-activated killer-cell therapy for metastatic renal cell carcinoma.

PURPOSE: Two consecutive protocols of continuous intravenous (CIV) infusion interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells were carried out in patients with metastatic renal cell carcinoma (RCC) to determine the response rate and toxicity. PATIENTS AND METHODS: In both protocols, patients received induction IL-2 at 6 x 10(6) U/m2/d on days 1 to 5, and underwent leukapheresis on days 7 to 9 at the peak of rebound lymphocytosis. LAK cells were generated by a 5-day incubation with IL-2 at 1,000 U/mL, and were infused on days 12 to 14. For the first 20 patients (protocol A), maintenance IL-2 was administered at 6 x 10(6) U/m2/d on days 12 to 16. On the assumption that less IL-2 might be required to maintain rather than to induce LAK activity, and that a longer duration of maintenance IL-2 might enhance LAK survival and function in vivo, the protocol for the subsequent 22 patients (protocol B) was altered so that the maintenance phase consisted of a lower dose of IL-2 (2 x 10(6) U/m2/d) administered for a longer period of time (days 10 to 20). RESULTS: In protocol A, there were two complete responses (CRs) and three partial responses (PRs), for a total response rate of 25%. One PR was surgically converted into a CR. The durations of the CRs are 36+, 18+, and 18+ months. Hypotension and capillary leak were most severe during maintenance, which limited the median duration of maintenance IL-2 to 4 days. In protocol B, no patient experienced severe hypotension, and the median duration of maintenance IL-2 was 9 days. Two patients exhibited a CR and seven a PR, for a total response rate of 41%. Two PRs were surgically converted to CRs. The durations of CR are 14+, 9+, 6+, and 5+ months. In both protocols, the CIV induction regimen resulted in marked rebound lymphocytosis (mean, 11,097/microL) and LAK-cell yield (mean, 18.1 x 10(10)). The cumulative response rate was 14 of 42 patients, or 33% (95% confidence interval, 19% to 47%). CONCLUSION: These results demonstrate that both protocols of CIV IL-2 plus LAK cells have substantial antitumor activity, and that a longer maintenance phase of IL-2 at a lower dose is associated with significantly less toxicity without a loss of therapeutic efficacy.

Adult↗
PubMed1992

Radiology and treatment of urinary tract stone disease.

Renal and ureteral calculi are treated primarily using extracorporeal lithotripsy, with percutaneous nephrostolithotomy retaining an important role for the treatment of large stones and complex situations. Aspects of pretherapy evaluation are reviewed. The vast majority of calculi 5 mm or less in diameter in the mid and lower ureter will pass spontaneously; in patients with acute ureteral obstruction, lower-osmolar nonionic contrast for urography caused as much discomfort as conventional high-osmolar contrast. Treatment planning for extracorporeal lithotripsy has changed in that internal stenting is no longer routinely recommended. Milk-of-calcium and calyceal diverticular stones respond poorly to extracorporeal lithotripsy. The access route used for percutaneous stone removal varies among investigators. Some advocate an intercostal approach for up to one third of patients; substantial complications occur with placement of a track above the 11th rib. Sepsis develops after percutaneous nephrostomy in up to 21% of patients, but the risk of sepsis can be decreased significantly by the administration of antibiotics during and after the procedure. Complications of extracorporeal lithotripsy include renal hematoma (especially if the patient is hypertensive or is taking aspirin), regional organ injury, and bacteremia. Although originally feared to occur frequently, hypertension occurring after or caused by extracorporeal lithotripsy was not confirmed to be a major problem. The incidence in a 2-year postlithotripsy follow-up was no greater than that for control subjects.

Humans↗
PubMed1991

Endopyelotomy: review of results and complications.

Percutaneous endopyelotomy augmented by balloon dilation was performed on 27 of 40 patients for the treatment of symptomatic, primary ureteropelvic junction obstruction. Percutaneous ultrasonic lithotripsy was performed simultaneously on 12 of 27 patients (44%) for associated calculi. After endopyelotomy 24 of 27 patients became asymptomatic (clinical success rate 89%). Three clinically improved patients demonstrated only radiographic stability, while radiographic improvement was documented in 21 of 27 (radiographic success rate 78%). Adjuvant percutaneous ultrasonic lithotripsy was successful from the standpoint of stone removal in all patients and no increased morbidity could be identified. Of 27 patients 3 (11%) suffered major complications and are considered failures. Reasons for failure varied and are discussed. Included is a patient who at nephrostography and stent capping became septic and subsequently died. To decrease the risk of sepsis perioperative antibiotics to include at the time of nephrostomy tube capping are recommended. Angiography was performed in 19 of 40 patients to rule out an accessory crossing vessel at the ureteropelvic junction, and such a vessel was found in 6. From analysis of presenting excretory urograms (IVPs) we conclude that a crossing vessel cannot predictably be identified on an IVP.

Catheterization↗
PubMed1991

Acute reactions to intravascular contrast media: types, risk factors, recognition, and specific treatment.

Acute, potentially life-threatening systemic reactions to contrast media are less frequent with lower osmolality, nonionic contrast agents, but they are not totally eliminated. Severe reactions remain a reality in all radiology departments. Typical reactions to contrast media include nausea and/or vomiting, scattered to extensive urticaria, bronchospastic reaction, hypotension (isolated) with compensating tachycardia, anaphylactoid reaction, vagal reaction, cardiovascular collapse, convulsion, and seizure. For each type of reaction, rapid recognition and initiation of specific corrective therapy enhance response and minimize side effects of drugs. Specific drugs for treating each reaction type are reviewed, including recommended dose, contraindications, and alternative choices. An approach to the high-risk patient and prevention of acute systemic reactions is discussed and pretreatment protocols are outlined.

Anaphylaxis↗