Are portable bladder scanning and real-time ultrasound accurate measures of bladder volume in postnatal women?

Real-time ultrasound and portable bladder scanners are commonly used instead of catheterisation to determine bladder volumes in postnatal women but it is not known whether these are accurate. Change in bladder volumes measured by ultrasound and portable scanners were compared with actual voided volume (VV) in 100 postnatal women. The VV was on average 41 ml (CI 29 - 54 ml) higher than that measured by ultrasound, and 33 ml (CI 17 - 48 ml) higher than that measured by portable scanners. Portable scanner volumes were 9 ml (CI -8 - 26 ml) higher than those measured by ultrasound. Neither method is an accurate tool for detecting bladder volume in postnatal women.

A Double-Blind, Randomized, Placebo-Controlled Trial of Prilocaine and Felypressin (Citanest and Octapressin) for the Relief of Pain Associated with Cervical Biopsy and Treatment with the Semm Coagulator

OBJECTIVE

To quantify the anticipated and actual pain experienced in association with preliminary cervical punch biopsies and subsequent ablative treatment with the Semm coagulator, and to test the hypothesis that the intracervical injection of prilocaine with felypressin reduces the intensity of the pain experienced.

MATERIALS AND METHODS

One hundred consecutive women referred with abnormal cervical smears for colposcopic assessment and considered suitable for treatment with the Semm coagulator were recruited to a double-blind, randomized, prospective, placebo-controlled trial conducted in a colposcopy clinic in a university teaching hospital. Personal particulars were taken and anticipated pain scored. The patients were injected with randomized externally identical vials of prilocaine and felypressin (Citanest and Octapressin) or placebo. After biopsy and treatment, patients scored their actual pain experienced. Pain scores were compared as the main outcome measure. Relative risks with 95% CIs were calculated and compared using the CI Analysis computer programme (Professor Martin J Gardner and the British Medical Journal Version 1.1, copyright 1991).

RESULTS

Anticipated pain was greater than the actual pain experienced in both groups. Women receiving the local anesthesia experienced a significantly greater reduction in pain (p < .05) with only 4.3% and 6.7% experiencing moderate pain during biopsy and treatment, respectively. The active drug abolished severe pain. In the placebo group, 44.7% felt mild pain at the most.

CONCLUSIONS

Intracervical injection of prilocaine and felypressin reduces the intensity of pain experienced in women undergoing cervical biopsy and treatment with the Semm coagulator. Its use is commendable but is not absolutely necessary in all cases.

Tension free vaginal tape: a procedure for all ages

OBJECTIVE

To assess the success and complications of the tension free vaginal tape (TVT) procedure in different age groups.

PATIENTS AND METHODS

This prospective long-term study of 179 consecutive cases of urodynamically confirmed urinary incontinence that had had the TVT procedure was conducted from March 1999 to December 2002 at a District General Hospital. To assess whether outcome was influenced by the patient's age, the patients were divided into three age groups: group A (30-49 years old), group B (50-69 years old) and group C (70-90 years old). Operative details and early and late complications were recorded, and patients were followed up with clinic visits at 6 weeks and 6 months and a quality of life questionnaire was completed at 1 year.

RESULTS

Of the 179 patients included in the study, 53 (29.6%) were in group A, 91 (50.8%) in group B and 35 (19.5%) in group C. The subjective cure rate for the patients was 84.9%, 81.3% and 85.3% in groups A, B and C, respectively. A significant improvement in symptoms was reported by 3.8%, 14.3% and 8.6% women, respectively. The failure rate was 11.3%, 4.4% and 5.7%, respectively. The intraoperative complication rate was 5.6%. The overall postoperative complication rate was 29.6%. A total of 86.2% of the patients were treated as day cases. Patients who had intraoperative complications or initial voiding difficulties (i.e. those patients requiring "in/out" catheterization before spontaneous voiding was established) were in hospital for 1-2 days.

CONCLUSIONS

Our data showed better subjective cure rates and substantial improvement rates without any significant increase in intraoperative complications with increasing age. Postoperative complications of urgency and vaginal wall erosion were more common in the older aged patients but were easily resolved. Hospital stay and recovery period were short, making TVT a suitable procedure for all ages.

In vitro evaluation of gallstone dissolution with methyl-tert-butyl ether and ultrasound energy

Given the large number of cholecystectomies performed annually, a nonsurgical approach to gallstone therapy is of great interest. A laboratory ultrasound system has been developed to study enhancement of methyl-tert-butyl ether (MTBE) dissolution of human gallstones in vitro. A mathematical model that quantitatively characterizes the dissolution process via a rate constant has been developed. Using this model, the kinetics of 15 gallstones from a single patient were evaluated for three dissolution methods: 1) unstirred MTBE, 2) aspirated MTBE, and 3) ultrasonically enhanced MTBE. The results showed excellent fits between the model and measured dissolution rates. 195 kHz continuous-wave (CW) ultrasonically enhanced dissolution rates exhibited a 6.2 fold gain over the manually aspirated MTBE and a 49.5 fold gain over static MTBE dissolution. Investigation of 50% duty cycle pulsed mode ultrasound revealed that total power appears to be the determinant of the observed dissolution rates. Gallstone calcification showed a strong correlation with dissolution rates measured by the model.

A beamformer for the acquisition of evoked potentials

Evoked potentials (EP) contain information about various physiological parameters and the estimation and detection of these signals can aid in the diagnosis of many pathological conditions. However, the signal-to-noise ratio (SNR) for EP measurement is often very low, and thus signal processing techniques must be employed to enhance the SNR. A delay and sum beamformer acquisition system has the potential for significant SNR improvement in EP measurements. In this communication it is shown that an electrode array acquisition system implements a uniform coherent delay and sum beamformer. The performance of the beamformer is characterized in terms of the number of electrodes, and cross-channel correlation. When compared to conventional ensemble averaging, the beamformer reduces the number of response repetitions required to achieve a given SNR by a factor which approaches the number of channels in the acquisition system.