A computer integrated prostatectomy system named PROBOT has been produced to aid in the resection of prostatic tissue. The system is image guided, model based, with simulation and online video monitoring. The development and trial of the system have not only demonstrated the successful robotic imaging and resection of the prostate, but have also shown that soft tissue robotic surgery in general, can be successful.

A method to optimise the whole process of operation/vaporising the prostate tissue using a prostatectomy robot to relieve urethra blockage is presented. The cavity that closely satisfies the surgeon defined model can be created by robot in half of the time that done manually, The desired vaporising region can even be reshaped during the operation, resulting in new optimised vaporising sequence that excludes the region already operated. The method also excluds vulnerable regions from operation for safety, All models maintained benefit for pre/intra/post-operation evaluation. The method exhibits a promising future for the application of robotic prostatectomy and robotic surgery on soft tissue in general.

As men age, their prostates can enlarge, causing urinary difficulty. Surgery to correct this [transurethral resection of the prostate (TURP)] is a skilled and time-consuming operation requiring many repetitive motions of a cutter. A robot has been developed to perform these motions, relieving the surgeon of much of the burden of surgery. This robot has been tried both in the laboratory and later on human subjects and has proved itself capable of performing prostate resection. The Probot system consists of on-line imaging and three-dimensional prostate model construction, an appropriate surgeon-computer interface, a counterbalanced mounting frame and a computer controlled robot.

OBJECTIVE:To compare the volumes and dimensions of the prostate gland as measured by transrectal and transurethral ultrasonography (TRUS and TUUS) and to study the prostatic changes that occur in the presence of an urethral instrument.PATIENTS AND METHODS:Twenty men (mean age 71 years, range 43-85) with symptoms of prostatic enlargement underwent TRUS and the dimensions and volumes of their prostates were obtained by the dimensional method and by step planimetry. Within 24 h, all the men were examined cystoscopically under sedoanalgesia and underwent TUUS. Their prostatic volumes and dimensions were again measured by the dimensional method and by step planimetry. Step planimetry was carried out using a specially designed indexer firmly attached to the examination couch or operating table. All the static images and planimetry slices were video recorded for later computer enhancement and to study the three-dimensional changes occurring in the prostate. The volumes and dimensions obtained by TRUS and TUUS were compared.RESULTS:Volumes obtained by transurethral step planimetry were 22% greater than those from transrectal planimetry. Although there was a good correlation (r = 0.984) between transurethral planimetry and the volumes derived using the transurethral dimensions with the prolate ellipsoid formula, the latter produced values 17% and 25% lower by the transurethral and transrectal routes, respectively. These volume estimates varied widely, indicating that the simple addition of a constant to the prolate ellipsoid formula would not correct the volume. Three-dimensional changes of the prostate occurred with TRUS and TUUS: with TUUS, the craniocaudal and anteroposterior diameters were significantly larger (by 7% and 18%, respectively) while the transverse diameter was smaller by 20%.CONCLUSION:The estimated volumes and dimensions of the prostate differed when measured by TRUS and TUUS and three-dimensional changes in the prostate occurred in the presence of an urethral instrument.

Transurethral electrovaporization of the prostate (TVP) is a new minimally invasive procedure to treat enlargement of the prostate. It was the aim of this study to compare the efficacy, post-operative morbidity and costs of transurethral resection (TURF) with TVP of the prostate. Forty men requiring a transurethral resection of the prostate over a period of 12 months were randomly selected to undergo either TURP (20 men) or TVP (20 men). The improvement in the urinary symptoms and peak urinary flow of the two groups were measured before and after surgery. The post-operative morbidity, hospital stay, operating time and the costs of the two procedures were analysed in detail. Both TURF and TVP were found to have the same efficacy in relieving prostatic symptoms and obstruction with a successful surgical outcome in 85% of the men. The mean hospital stay for the TVP group (1.85 days) was significantly lower than the TURF group (3.5 days) as were the postoperative bladder irrigation and catheterization time (P<0.0001). TVP was significantly cheaper than TURP due mainly to the reduced hospital stay, blood transfusions and cost of bladder irrigants. The overall morbidity was less for the TVP group (10%) in comparison to TUFF (15%). TVP is as effective as TURF in relieving prostatic symptoms while being less morbid and cheaper with a shorter hospital stay: probably a better alternative to TURF.

OBJECTIVES:To determine why there are variations in the volumes of the prostate obtained by step planimetry and those calculated from the prolate ellipsoid formula using the measured maximum gland dimensions, to assess the reproducibility of estimates of prostate volume from transrectal ultrasonography (TRUS) and to determine the effect of the angle of the transrectal probe, the human error in the clinical setting and the benefit of computer enhancement of the ultrasonograms.PATIENTS AND METHODS:Forty-five men (mean age 72 years, range 43-89) with symptoms of prostatic enlargement were divided randomly into three groups; those in group 1 had their prostate volume estimated three times by measuring the maximal gland dimensions and calculating the volume using the prolate ellipsoid formula (dimensional method) and by step planimetry, to assess the reproducibility of TRUS; men in group 2 had their prostate volume estimated using the dimensional method and by step planimetry with the probe in the optimal axis, and then from scans repeated after deflecting the transrectal probe 5 degrees anteriorly and posteriorly; men in group 3 had their prostate volume estimated once by the dimensional method and by step planimetry. Step planimetry was carried out using a specially designed indexer firmly attached to the examination couch. All 'frozen' images and planimetry slices were videotaped for later computer enhancement. The volumes and dimensions obtained by each method were compared.RESULTS:The volumes obtained by step planimetry were 17% greater than those obtained by the dimensional method because the craniocaudal, anteroposterior and transverse diameters were underestimated significantly by the latter (by 13%, 2% and 7%, respectively). The largest anteroposterior and transverse diameters were included in the same axial scan in only 44%, while the largest craniocaudal diameter was in the midline in only 38%, of the patients. The human error in the clinic was negligible (2%) with a good correlation between the dimensions and volumes obtained in the clinic and those from computer-enhanced images (r = 0.94). There were no advantages in computer enhancing the TRUS images. Volumes calculated from the dimensional method using the maximum dimensions obtained from planimetric contours correlated well with planimetric volumes (r = 0.93). The reproducibility of TRUS showed a mean error of 8% by the dimensional method and 1% by step planimetry. Anterior deflection of the transrectal probe reduced the estimated volume by 2% and posterior deflection increased the volume by 4%, using the dimensional method, while there were no significant volume changes when estimated by step planimetry.CONCLUSION:This study confirms that to estimate accurately the volume of the prostate using the prolate ellipsoid formula, the current methodology needs to be changed. The largest anteroposterior and transverse diameters may need to be measured in different transverse scan slices and the largest craniocaudal diameter in a sagittal scan away from the midline. If volume estimation is to be repeated then step planimetry is reliable and TRUS using the prolate ellipsoid formula is not.

The need for an alternative management to transurethral resection of the prostate (TURF) is indicated because of its known post-operative morbidity and the increasing incidence of benign prostatic hyperplasia requiring operation with a considerably costlier effect on health care budgets. Despite the search, no beneficial alternative has yet emerged and it is envisaged that robotizing the procedure may be of benefit. The design of a purpose-built robot is described which consists of a specially designed motorized safety frame, a dedicated motion controller, an integrated ultrasound and camera system and a computer system. The software and the procedural protocol are briefly described. Clinical trial is in progress with a rapid set-up time of only 8 min. It is concluded that the robot is ultimately expected to be an ideal alternative to conventional TURP.

The rapid development of minimally invasive surgery means that there will be fundamental changes in interventional treatment. Technological advances will allow new minimally invasive procedures to be developed. Application of robotics will allow some procedures to be done automatically, and coupling of slave robotic instruments with virtual reality images will allow surgeons to perform operations by remote control. Miniature motors and instruments designed by microengineering could be introduced into body cavities to perform operations that are currently impossible. New materials will allow changes in instrument construction, such as use of memory metals to make heat activated scissors or forceps. With the reduced trauma associated with minimally invasive surgery, fewer operations will require long hospital stays. Traditional surgical wards will become largely redundant, and hospitals will need to cope with increased throughput of patients. Operating theatres will have to be equipped with complex high technology equipment, and hospital staff will need to be trained to manage it. Conventional nursing care will be carried out more in the community. Many traditional specialties will be merged, and surgical training will need fundamental revision to ensure that surgeons are competent to carry out the new procedures.

Replacement of open surgery with minimally invasive techniques for treating stones in the renal tract has greatly reduced patients' morbidity and mortality and the period of hospitalisation and convalescence. Extracorporeal shockwave lithotripsy does not require anaesthesia and requires little analgesia so that treatment can be given on an outpatient basis, and there is no wound to heal. Only a small puncture site is needed for percutaneous endoscopic lithotomy, and with the advent of prophylactic antibiotics there are few complications. Of renal stones, about 85% can now be successfully treated by extracorporeal lithotripsy alone, and almost all of the stones too large or hard for lithotripsy can be treated endoscopically, with ultrasonic or electrohydraulic probes being used to fragment the stone. Stones in the upper and lower thirds of the ureter can be treated by extracorporeal lithotripsy, but stones in the middle third, which cannot normally be visualised to allow focusing of the shockwaves, usually require ureteroscopy. Nearly all bladder stones can be treated by transurethral endoscopy with an electrohydraulic probe. Only the largest renal tract stones still require open surgery.

The action of the motilin receptor agonist erythromycin on human gallbladder contraction, measured by ultrasound, both in normal subjects and those with gallstone disease was studied. In 17 normal subjects, oral erythromycin administration (500 mg; vs. placebo) reduced fasting gallbladder volume at 2 hours (26.2 vs. 19.0 mL; P less than 0.001), and postprandial residual gallbladder volume (9.0 vs. 4.4 mL; P less than 0.001) and the rate constant of gallbladder emptying following the meal was significantly increased. Erythromycin also reduced fasting and residual gallbladder volumes in 13 patients with gallstone disease: in 6 who underwent cholecystolithotomy, fasting volume was 29.5 vs. 22.3 mL (P less than 0.05) and residual volume was 17.7 vs. 6.5 mL (P less than 0.05), and in 7 with gallstones in situ, fasting volume was 23.8 vs. 14.3 mL (P less than 0.05) and residual volume was 17.2 vs. 5.0 mL (P less than 0.05). In 7 of 8 subjects with gallstones and impaired gallbladder emptying, the gallbladder emptied normally following administration of erythromycin, and in 3 of the other 5 gallstone subjects gallbladder emptying was increased. In 6 normal subjects given erythromycin three times weekly for 1 month, the effect was maintained (fasting volume, 18.8 mL, P less than 0.001; residual volume, 3.7 mL, P less than 0.001). Oral erythromycin significantly reduces fasting and postprandial residual gallbladder volumes in both normal subjects and subjects with gallstones and reverses the gallbladder motility defect found in a proportion of subjects with gallstones. This effect is maintained for a month in normal subjects.

Although the concept of prostate liquefaction had been proposed by Wickham 15 years ago, its clinical application has been delayed by various technical problems. The authors report on the investigative procedures that have been undertaken to design and develop the ELSA (Endoscopic Liquidiser and Surgical Aspirator) prototype which has been utilized in the clinical setting with promising results.