Hemodynamic patterns of pharmacologically induced erection: evaluation by color Doppler sonography

PURPOSE

Penile erection is achieved through hemodynamic mechanisms that can be assessed best with color flow imaging and Doppler waveform analysis. We performed dynamic studies using computer assisted analysis to assess the hemodynamic patterns of pharmacologically induced erection.

MATERIALS AND METHODS

A total of 73 color Doppler ultrasound studies was performed in 66 patients with erectile dysfunction. Various blood flow parameters, including peak systolic velocity, end diastolic velocity, mean flow rate, resistive index and artery diameter, were observed continuously and recorded frequently for about 30 minutes after intracorporeal injection of papaverine/phentolamine/prostaglandin E1 mixture. A computerized Doppler waveform analysis of 3 curves or greater was performed for each recording to minimize error. A second injection was administered if the first injection failed to induce a rigid erection. Status of the erection was observed and recorded throughout the study. A computerized graph was generated for each corpus.

RESULTS

After intracorporeal injection the time to reach normal or peak velocity varied from 1 to 24 minutes. Among 146 corpus units in 73 color Doppler ultrasound studies we observed the following hemodynamic patterns: I-normal maximal peak systolic velocity (35 cm. per second or greater), sustained; Ia-end diastolic velocity 0 or less with complete erection response (19 units); Ib-end diastolic velocity greater than 0 or incomplete erection response (14 units); II-normal maximal peak systolic velocity (35 cm. per second or greater), transient; IIa-end diastolic velocity 0 or less with complete erection response (21 units); IIb-end diastolic velocity greater than 0 or incomplete erection response (12 units); III-borderline maximal peak systolic velocity (30 to 35 cm. per second); IIIa-end diastolic velocity 0 or less with complete erection response (10 units); IIIb-end diastolic velocity greater than 0 or incomplete erection response (8 units); IV-low maximal peak systolic velocity (less than 30 cm. per second); IVa-end diastolic velocity 0 or less with complete erection response (24 units); and IVb-end diastolic velocity greater than 0 or incomplete erection response (38 units).

CONCLUSIONS

Erection is a complex and dynamic process. A new classification of hemodynamic patterns is presented that aids in assessing and interpreting more thoroughly blood flow parameters to stratify more precisely the hemodynamic patterns of erectile dysfunction.

Color Doppler ultrasound criteria to diagnose varicoceles: correlation of a new scoring system with physical examination

OBJECTIVES

Color Doppler ultrasound (CDU) diagnostic criteria for varicoceles are poorly defined, and the role of CDU in diagnosing varicoceles is controversial. The purpose of this study is to assess the diagnostic accuracy of CDU for varicoceles compared to physical examination.

METHODS

We prospectively studied 64 patients with CDU and collected the following data: maximum diameter of scrotal veins, the presence of a venous plexus, sum of the diameter of up to six veins of the plexus, and the duration and amplitude of flow change on Valsalva maneuver. To avoid interphysician variation, all patients were examined by one designated senior urologist with the sonographer remaining unaware of the findings.

RESULTS

CDU parameters of 127 testis units in 64 patients were analyzed and compared to the physical findings. Fifty-nine testis units were positive and 57 units were negative for varicocele on physical examination. In 11 testis units, results of physical examination were inconclusive regarding the presence of varicocele. The commonly accepted CDU criterion for varicocele (maximal vein diameter of 3 mm or greater) had a sensitivity of 53% and specificity of 91% compared to physical examination. We developed a new scoring system incorporating the maximal venous diameter (score 0 to 3), the presence of a venous plexus and the sum of the diameters of veins in the plexus (score 0 to 3), and the change of flow on Valsalva maneuver (score 0 to 3). Using a total score of 4 or more to define the presence of CDU-positive varicocele, we observed a sensitivity of 93% and a specificity of 85% when compared to physical examination. All moderate to large varicoceles found on physical examination were positive by CDU diagnosis using the scoring system, but the same group had only a 68% positive rate by traditional CDU diagnostic criteria.

CONCLUSIONS

Using the proposed new scoring system, CDU has been shown to be a reliable and accurate method of diagnosis for varicoceles compared to the current reference standard physical examination. CDU has the advantages of being able to objectively examine venous plexus and measure blood flow parameters and to be less observer-dependent than physical examination.

Primary care--opportunities and threats. Developing prescribing in primary care

The latest white papers on the NHS focus on stimulating innovation in the delivery of primary care and removing barriers to further development. Some of this innovation relates directly to prescribing in primary care, and in this article the authors speculate on what might happen if the prescribing initiatives referred to in the white papers were extended and disseminated more widely. The initiatives which might have the biggest impact are those encouraging closer collaboration between general practitioners and community pharmacists and those aiding extension of the current nurse prescribing scheme in primary care. Both offer considerable opportunities to improve primary care, but both bear some potential risks.

'Mouseyes': an aid to wound measurement using a computer

The aim of this study was to assess the efficacy of an image-area and perimeter-length measurement system consisting of a personal computer with integral mouse device and a computer program, 'Mouseyes', written for the purpose. The study was designed to see how image area, perimeter length and curvature affected the overall accuracy and reproducibility of measurement. Five volunteers (three male, four right-handed, one left-handed) were recruited to carry out the task of digitising a series of 12 shapes of known dimensions. The difference between derived and true image measurements were investigated. The accuracy and reproducibility of area measurement increased with increasing area magnitude. Digitised areas were typically calculated with an error of 1.3% or less. The coefficient of variation was less than 2%, indicating a high reproducibility of measurement; the greatest inaccuracies and variability occurred with smaller sizes. The system has been proved to be a reliable, accurate and reproducible method for the measurement of irregularly shaped areas and linear dimensions.

Age differences in patterns and correlates of the frequency of prayer

This study examines differences by age cohort in (a) the frequency of prayer, (b) racial and gender variation in prayer, and (c) religious and sociodemographic correlates of prayer. Analyses are conducted across four age cohorts (18-30, 31-40, 41-60, > or = 61) using data from the 1988 National Opinion Research Center (NORC) General Social Survey (N = 1,481). Findings reveal that prayer is frequently practiced at all ages, but more frequently in successively older cohorts. In addition, females and, to a lesser extent, African Americans pray more frequently than males and Whites, respectively. Further, hierarchical multiple regression analyses reveal statistically significant associations across age cohorts between prayer and key measures of religious behavior, feeling, belief, and experience.

Nonsurgical treatment of basal cell carcinomas with intralesional 5-fluorouracil/epinephrine injectable gel

BACKGROUND

To develop a nonsurgical treatment alternative for basal cell carcinomas (BCCs), we evaluated intralesional sustained-release chemotherapy with 5-fluorouracil/epinephrine injectable gel (5-FU/epi gel).

OBJECTIVE

To optimize the dose and treatment schedule, we compared the safety, tolerance, and efficacy of six treatment regimens of 5-FU/epi gel in patients with BCCs.

METHODS

Two doses and four treatment schedules of 5-FU/epi gel were compared in an open-label, randomized study of 122 patients with biopsy-proven BCCs. One BCC per patient was treated for up to 4 to 6 weeks, then observed for 3 months at which time the tumor site was completely excised for histologic examination.

RESULTS

Overall, 91% of evaluable treated tumors (106 of 116) in all regimens had histologically confirmed complete tumor resolution. No clinically significant treatment-related systemic adverse events occurred. The best response rate, tolerance, and patient compliance with assigned dose were in patients receiving 0.5 ml of 5-FU/epi gel three times a week for 2 weeks. The complete response rate based on histologic assessment in this group was 100%.

CONCLUSION

Results demonstrate that treatment of BCC with 5-FU/epi gel is both safe and effective, may result in histologically confirmed complete response rates comparable to surgery, and provides a nonsurgical treatment alternative in selected patients.

A comparison of three methods of bag valve mask ventilation

A method of bag valve mask ventilation in which the resuscitator compresses the self inflating bag between their open palm and the side of their body was compared with conventional single and two resuscitator bag valve mask ventilation. Fifteen nurses each ventilated three patients for 4 min following the induction of general anaesthesia, using one method per patient in random order. Tidal volume and peak mask pressures were higher with the two resuscitator technique than with either form of single resuscitator ventilation; There were no significant differences between the two methods of single resuscitator ventilation. Tidal volume: mean (S.D.); 'open palm': 270 ml (160); single resuscitator: 260 ml (220); two resuscitators: 480 ml (210). Peak mask pressure (mmHg): mean (SD); 'open palm': 19 (8); single resuscitator: 17(9); two resuscitator: 28 (11).

The cost of medicines in the United Kingdom. A survey of general practitioners' opinions and knowledge

Prescribing costs in general practice continue to grow. Their importance is underlined by the amount of information concerned with costs that general practitioners (GPs) receive, and by the existence of target budgets. In 1986 and 1991, surveys showed that GPs agreed that cost should be borne in mind when choosing medicines, but that their knowledge of drug prices was often inaccurate. This study assessed the current knowledge and attitudes of GPs in the UK in respect of prescribing costs, and examined the influence of various developments in general practice since 1986 on the accuracy of drug price estimation. 1000 randomly selected GP principals (500 in Scotland and 125 in each of 4 English health regions) were sent a postal questionnaire. The GPs' level of agreement with 5 statements concerned with prescribing costs, and the accuracy of their estimates of the basic price of 31 drugs, were analysed. Most GPs (71%) agreed that prescribing costs should be taken into account when deciding on the best treatment for patients. Fundholders were more likely than non-fundholders: (i) to agree that prescribing costs could be reduced without affecting patient care; (ii) to agree that providing more information on costs would lower the cost of prescribing; and (iii) to comment that cost guidelines had changed their prescribing habits. Fundholders were less likely than non-fundholders to reject the principle of fixed limits on prescribing costs. Overall, one-third of the price estimates given were accurate (within 25% of the actual cost). For the most expensive drugs in the survey [those priced over 10 pounds sterling (Pound) per pack], half of the price estimates were accurate. There were significant differences between non-fundholders' and fundholders' estimates of the price of less expensive drugs (those priced at less than 10 pounds per pack). Use of a formulary or computer-displayed drug price information did not affect the accuracy of price estimates. It may be that GPs who were more knowledgeable and concerned about costs were more likely to become fundholders. It is also possible that the expansion of fundholding, or other mechanisms that give GPs responsibility for resource allocation, might improve accurate cost awareness in prescribing. Clinical and economic review of repeat prescribing is recommended.

Morbidity and prescribing patterns for the middle-aged population of Scotland

BACKGROUND

As part of a large national survey of morbidity recording on general practice computers, morbidity and prescribing data were collected from three separate sources for more than 10,000 patients aged 45-64 years, randomly selected from 41 Scottish general practices.

AIM

To amalgamate the three sources of data to provide estimates of prevalence rates for a range of common chronic diagnoses, and of medication rates for associated repeat prescription drugs.

METHOD

Forty-one Scottish general practices were selected on a geographic basis in relation to the national population distribution. Within each practice, 250 patients aged 45-64 years were selected at random. Data relating to 19 diagnoses and 40 repeat prescription drugs were extracted from the computer records of these patients and compared with information held on patients' paper records and supplied by patients in response to a postal questionnaire. After assessing the completeness and accuracy of computer-held information, the three sources of data were amalgamated according to agreed protocols.

RESULTS

Lifetime prevalence rates are presented for each diagnosis, broken down by sex and age group. Differences in rates between the sexes, and with change in age, were in the expected direction for all diagnoses, and were matched by corresponding differences in entitlements to repeat prescription drugs. Comparison of these lifetime rates with published prevalence rates indicates a latent pool of morbidity within the community, which ranges from 1.0 to 10.0 times the annual prevalence rate for different conditions.

CONCLUSION

The amalgamated data provide an estimate of lifetime prevalence rates for the range of conditions examined. They complement conventional morbidity statistics and have potential value in allowing the underlying management costs of specific chronic conditions to be evaluated.

Analysis of early readmissions after combined pancreas-kidney transplantation

Combined pancreas-kidney transplantation (PKT) has become generally accepted as an effective treatment option, but controversy exists regarding the early morbidity rate of the procedure. To address this issue, we retrospectively analyzed all readmissions occurring in the first 3 months after PKT. Over a 5-year period, we performed 98 PKTs with bladder drainage. The mean recipient age was 36.6 years, with a mean pretransplant duration of diabetes of 23.5 years. All patients received quadruple immunosuppression with antilymphocyte induction therapy. The mean length of initial hospital stay was 20 days. One hundred forty-five readmissions occurred in 73 patients (74.5%), with the initial readmission occurring at a mean of 8.5 days after hospital dismissal and 28 days after PKT. Twenty-five patients (25.5%) had no readmissions, 35 (36%) had one readmission, 17 (17%) had two readmissions, and the remaining 21 patients (21.5%) had three or more readmissions in the first 3 months. The mean number of readmissions was 1.5 per patient. Forty-seven patients (48%) were readmitted within 1 week, and all but one initial readmission occurred within 1 month of hospital dismissal. Causes of readmission included rejection (51), infection (32), pancreas-specific morbidity (such as dehydration, hematuria, or pancreatitis; 50), and miscellaneous causes (12). Thirteen patients (13%) underwent reoperation during readmission. The mean length of hospital stay during readmission was 7.6 days. The mean total length of hospitalization in the first 3 months after PKT was 31 days. Over the span of 5 years, no changes have occurred either in the incidence, timing, causes, or duration of readmissions. The patient survival rate is 96%, the kidney graft survival rate is 90%, and the pancreas graft survival rate is 88% after a mean follow-up of 2.6 years. Mean rehabilitation time (return to work or normal activity) after PKT was 4.0 months. In conclusion, PKT is associated with a fixed morbidity characterized by early readmission (within 1 week) in nearly half of patients and pancreas-specific morbidity as the cause in 35% of readmissions. During evaluation, prospective candidates should be counseled regarding the unique morbidity of PKT. Successful management strategies must emphasize the intensity of early follow-up and recognize the propensity toward immunologic, metabolic, exocrine, and urologic side effects.

Expression of human cytochrome P4501A1 (CYP1A1) in Saccharomyces cerevisiae inhibits cell division

1. Saccharomyces cerevisiae cells, genetically engineered to express human cytochrome P4501A1 (CYP1A1), have a mean doubling time of 5.8 h, which is considerably slower than that of control yeast cells that have undergone the same transformation process but with a plasmid lacking CYP1A1 cDNA (3.3 h). 2. A smaller reduction in the rate of cell division is observed in yeast cells expressing the closely related human P450, CYP1A2. No reduction is seen with plaice CYP1A, despite similar levels of P450 expression and enzyme activity (ethoxyresorufin O-deethylation) and no inhibition of growth is observed with yeast cells expressing higher levels of human CYP2D6. 3. Repeated culture of cells from a single CYP1A1 transformant colony results in a gradual loss of P450 expression and of CYP1A1-associated enzymatic activity over a 5-6 week period. In contrast, expression of human CYP2D6 by a single transformant colony is stable for at least 6 months. 4. The loss of CYP1A1 activity from transformed cells is accompanied by a return to normal growth rate, similar to that of control cells. 5. Inhibition of CYP1A1 enzyme activity during culture, by either type I (alpha-naphthoflavone), type II (ellipticine) or mechanism-based (1-(1'propynyl)pyrene) CYP1A inhibitors, does not affect growth rate, suggesting that some other property of human CYP1A1 protein is responsible for the growth inhibition observed.

Long-term outcome of prostatic stent treatment for benign prostatic hyperplasia

OBJECTIVES

To evaluate the long-term result of prostatic stent treatment for patients with benign prostatic hyperplasia (BPH).

METHODS

We reviewed our experience with prostatic stents in 24 patients with bladder outlet obstruction caused by BPH for whom up to 63 months of follow-up data were available.

RESULTS

Prostatic stents were successfully placed in 24 of 25 patients enrolled in the study. All 9 patients treated for urinary retention voided spontaneously after stent placement. In 14 (93%) of 15 patients with nonretention, voiding symptoms decreased by 50% or more. The stent was removed in 9 patients for persistence of symptoms, symptom recurrence, or stent migration. Nine patients died of unrelated causes during the follow-up period. The stents functioned adequately in these patients until death. In the remaining 6 patients, the stent was still in place at the last follow-up visit (range 12 to 52 months, average 35) after placement, and their Madsen-Iversen symptom scores ranged from 3 to 10. Fourteen patients underwent cystoscopy 1 to 37 months after stent placement. Epithelium did not completely cover the stent in any of these patients; however, no stone formation was noted.

CONCLUSIONS

Prostatic stents can be effective in relieving bladder outlet obstruction caused by BPH. They appear to be most useful in patients at high surgical risk and with a limited life expectancy. However, stent removal, which can be difficult, may be required in more than one-third of patients. We recommend prostatic stent placement primarily in patients who would otherwise be relegated to an indwelling catheter.

Contemporary criteria for cadaveric organ donation in renal transplantation: the need for better selection parameters

A major problem facing transplantation is the disparity between the availability of cadaver donors and the number of recipients awaiting transplantation. Efforts to deal with this issue have involved the use of "marginal donors." Results obtained using these organs have often been significantly worse at 1 and 3 years of follow-up. The problem of how to select and utilize these donors is of critical importance to both patients and society. Current criteria available for assessing cadaver donors are based on ideal donors. Although these appear adequate for predicting the results for the ideal donor, they are not adequate for assessing results for marginal donors. New criteria are of critical importance for better utilization of these organs. The purpose of this review is to examine the current criteria for ideal and marginal donors, review the critical issues to be clarified, and discuss options for improvement results in the future.

General practice blood pressure recording in Scotland: variations in the classification of hypertension

A questionnaire concerning blood pressure assessment, as part of health promotion activity, was circulated to all 770 Gpass practices in Scotland producing a 64.6% response rate. The results reveal a wide range in both the systolic and diastolic levels chosen to classify blood pressure as normal, borderline raised or raised. Practices are using a variety of values to indicate hypertension when considering systolic and, to a lesser extent, diastolic pressure. The variations found suggest that both over and under treatment are a significant risk to patients. The introduction of the 1993 health promotion regulations means that practices are required to actively target their practice population for blood pressure assessment and appropriate intervention. We suggest that this process will be enhanced if doctors are encouraged to adopt the established guidelines for the classification of blood pressure or general practice computer software is adopted to offer blood pressure protocol support.

Pancreas allograft rejection: correlation of transduodenal core biopsy with Doppler resistive index

PURPOSE

To determine the usefulness of sonographically obtained resistive indexes (RIs) in the diagnosis of pancreas allograft rejection.

MATERIALS AND METHODS

Findings were studied from 78 transduodenal pancreas allograft biopsies that were ultrasound-guided and cystoscopically directed. The 78 biopsies included 40 that were compared directly with baseline RI data. Biopsies were categorized by result and correlated with concurrent RIs (including 26 RIs obtained within 24 hours of biopsy) with the chi2 test for categoric variables and the Student t test for continuous variables. Sensitivity, specificity, and positive and negative predictive values were calculated with standardized formulas.

RESULTS

The mean RIs between the no rejection, mild acute rejection, and moderate acute rejection groups were not statistically significantly different; however, the mean RI associated with chronic rejection was statistically significantly higher (P < .05) than that in the other groups. The sensitivity, specificity, and positive and negative predictive values of either an elevated RI (> 0.70) or greater than 10% increase in the RI above the baseline value in the diagnosis of acute rejection were approximately 50%.

CONCLUSION

Neither the absolute level of the RI nor the relative increase was correlated with acute rejection proved at biopsy. Changes in RIs after pancreas transplantation were a poor indicator of acute rejection, but the absolute value of the RI was elevated in cases of chronic rejection.

Mesenteric arteriovenous fistula after vascularized pancreas transplantation resulting in graft dysfunction

Mesenteric arteriovenous fistula (AVF) is an unusual complication after vascularized pancreas transplantation. We report the case of a patient who developed a mesenteric AVF in the transplanted mesenteric bundle which resulted in severe and protracted endocrine insufficiency necessitating reinstitution of insulin therapy. This was reversible with surgical correction of the AVF. This complication should be included in the differential diagnosis of pancreas allograft dysfunction.

Humoral graft-versus-host disease after pancreas transplantation with an ABO-compatible and Rh-nonidentical donor. Case report and a rationale for preoperative screening

Severe hemolysis and graft ischemia complicating solitary pancreas transplantation with an ABO-compatible, Rh-negative, anti-D-positive donor to Rh-positive recipient is described in this article. A brief review of the literature is presented. A rationale for preoperative screening for red cell antibodies during solid organ transplantation in this special setting is discussed.

The application of an artificial neural network to Doppler ultrasound waveforms for the classification of arterial disease

In this study we have investigated the application of an Artificial Neural Net classifier to the diagnosis of vascular disease using Doppler ultrasound blood-velocity/time waveforms. A multi-layer perceptron network was trained with waveforms from control subjects and from patients with arterial disease. The diseased cases were confirmed by angiography and allocated to three groups according to the location of the stenosis: proximal or distal to the site of measurement or multi-segmental. We compared network classification results with a Bayesian classifier following a Principal Component Analysis of the waveforms. Versions of both classifiers were trained to discriminate two classes (normal v. abnormal) and four classes. In both cases the neural networks gave superior discrimination to the Bayesian classifier. While the four-class network was unable to provide useful discrimination among the stenosis sites, discrimination between abnormal classes was obtained which is comparable to that achieved by a human expert observer.