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K Taari

Publications and source records attributed to K Taari.

At least 19 recordsLinked to original sources
PubMed2004

Laparoscopic versus open nephrectomy for renal cell carcinoma?

Laparoscopic radical nephrectomy has become a well-standardized and reproducible, but technically demanding procedure. It is rapidly replacing the traditional open technique in radical nephrectomy with T1-2 tumours. Open operation will mainly be reserved for T3 tumours. Nephron-sparing surgery will play a major role in small (<4 cm) peripheral tumours. Open technique is still the standard for NSS, but with the refined techniques, laparoscopy may be soon coming.

Carcinoma, Renal Cell↗
PubMed2002

Viscoelastic memory and self-expansion of self-reinforced bioabsorbable stents.

The possibility to decide the speed and rate of expansion of stents is of great clinical importance by reason of the varying requirements for different indications to use stents. Self-reinforced bioabsorbable stents can be made self-expanding owing to the viscoelastic memory of the material. Stents are stable at room temperature and expansion occurs at body temperature. The level at which the expansion stops depends on the material, crystallinity, initial diameter of spira and annealing temperature. The expansion rate can be estimated by logarithmic equation, if material, draw ratio and diameter of stent wire are constant. This is, however, possible only if processing parameters are constant. Based on the present results annealing temperature and expansion time were seen to be directly proportional to the expansion rate of the stent.

Animals↗
PubMed2001

Endorectal magnetic resonance imaging of prostatic cancer: comparison between fat-suppressed T2-weighted fast spin echo and three-dimensional dual-echo, steady-state sequences.

The aim of this study was to develop an endorectal MRI strategy for prostatic cancer. We evaluated the MR images from 44 consecutive prostatic cancer patients treated by radical prostatectomy. Each sequence from every examination was assessed separately with a specific tumor map drawn. Tumor localization, capsular penetration, and seminal vesicle invasion were marked on maps on the basis of T2 and DESS (dual-echo steady-state) sequences. Thirty patients also had T1-weighted images, and these were assessed with regard to possible tumor outgrowth. The maps were compared with histopathological findings from radical prostatectomy specimens. According to our study, DESS equaled T2 in every respect. No statistically significant differences between the sequences were found with respect to detecting either tumor localization, outgrowth, or seminal vesicle invasion. DESS is a potential new sequence in prostatic MRI as it has been proven to parallel the routinely used T2-weighted imaging.

Aged↗
PubMed2001

Optimal timing of post-biopsy MR imaging of the prostate.

PURPOSE: To assess the quantity and frequency of hemorrhage after prostatic biopsy. As post-biopsy blood products may interfere with interpretation of MR images, we also investigated the optimal timing for MR examination after biopsy. MATERIAL AND METHODS: Fifteen patients scheduled for prostatic biopsies were imaged with endorectal MR before and after the procedure. In addition, MR studies of 42 patients with prostate cancer were retrospectively analyzed. The amount of post-biopsy blood product and the degree of its interference with image interpretation were assessed. RESULTS: Of a total of 57 patients, 44 (77%) had visible post-biopsy hemorrhage. However, the presence of blood products were considered to interfere with interpretation of the images in only 12 (21%) cases. This disturbing effect seems to diminish after 21 days from biopsy. The total amount of blood clearly decreased after 28 days. CONCLUSION: Deferring MR imaging for at least 3 weeks after prostatic biopsy is advisable. T1-weighted images are necessary to rule out false-positive findings caused by post-biopsy hemorrhage.

Aged↗
PubMed2001

Prostatic MR imaging. Accuracy in differentiating cancer from other prostatic disorders.

PURPOSE: We assessed the accuracy of MR imaging in differentiating between cancer and other prostatic disorders, and evaluated the diagnostic criteria for various prostatic diseases. MATERIAL AND METHODS: A total of 74 endorectal coil MR studies were performed on 72 patients. Twenty patients had prostatic cancer, 20 benign prostatic hyperplasia (BPH), 4 acute bacterial prostatitis, 5 chronic bacterial prostatitis (2 also belonging to the previous category), 19 chronic non-bacterial prostatitis/chronic pelvic pain syndrome, and 6 were symptomless voluntary controls. All studies were interpreted by two experienced radiologists in random order. Radiologists were blinded to all clinical data including the age of the patients. Based on MR findings, both radiologists filled in a form covering diagnostic criteria and diagnosis. RESULTS: Accuracy in diagnosing prostate cancer was 74%. Sensitivity was 50% and specificity 83%, and positive and negative predictive values were 53 and 82%, respectively. Bacterial prostatitis showed some features similar to carcinoma. Abundant BPH rendered cancer detection more difficult. No diagnostic criterion was clearly better than the others. Interobserver agreement on the MR diagnosis ranged from moderate to good. CONCLUSION: Without knowledge of accurate clinical data, MR seems to be too insensitive in detecting prostate cancer to be used as a primary diagnostic tool.

Aged↗
PubMed2000

Magnetic resonance imaging of prostatic cancer: does detection vary between high and low gleason score tumors?

BACKGROUND: Both Gleason score and prostate-specific antigen (PSA) concentration are prognostic factors for prostate cancer. We assessed our ability to localize cancer lesions based on Gleason scores and PSA values by endorectal coil magnetic resonance imaging (MRI). We also evaluated whether the size of the prostate affects tumor detectability. METHODS: We compared the findings of MRI and histopathological results of radical prostatectomy specimens from 63 patients; they were divided into four groups, based on Gleason score and also on serum PSA concentration. Furthermore, the possible effect of prostatectomy specimen weight on MRI interpretation was examined. RESULTS: A highly significant difference appeared in detection of cancer lesions based on their differentiation grade. No statistically significant difference existed between PSA groups in detection of tumors, but the large size of the prostate seemed to render image interpretation more difficult. CONCLUSIONS: Endorectal MRI detects poorly differentiated prostate cancer lesions more accurately than clinically insignificant tumors.

Aged↗
PubMed1999

Holmium:YAG laser for urinary stones.

OBJECTIVE: To evaluate the results of Holmium:YAG (Ho:YAG) laser lithotripsy in the treatment of urinary stones. MATERIAL AND METHODS: Between 1993 and 1997, 59 patients with 85 urinary stones were treated with the Ho:YAG laser lithotripsy. Retrospective evaluation was done on the 64 procedures available, comprising 53 ureteric, 8 bladder, and 2 renal calculi, and one stone in a ureterocele. RESULTS: The Ho:YAG laser fragmented all types of calculi. Of 38 patients, 29 (76%) with ureteric stones were stone-free and 7 (18%) had stone fragments smaller than 2 mm left 1-3 months after the lithotripsy, resulting in a total clinical success rate of 95%. The procedure caused four ureteric perforations. One ureteric stricture, after repeated treatments for a Steinstrasse formation, led to nephrectomy. CONCLUSIONS: The Ho:YAG laser was reliable and effective for most of the urinary stones. The largest stones in any location, and stones of hard composition, however, were treated with combined disintegration methods. Four minor ureteric perforations and one ureteric stricture were related to laser use.

Female↗
PubMed1999

Finasteride following balloon dilatation of the prostate. A double-blind, placebo-controlled, multicenter study.

BACKGROUND AND AIMS: To evaluate the efficacy, safety and tolerability of finasteride administered for 24 months following successful balloon dilatation in patients with benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: 75 patients with moderate to severe symptoms of benign prostatic hyperplasia were first treated with balloon dilatation. After a 4-week placebo runin period, 64 patients with successful dilatation and over 50 % reduction in symptoms were randomized to receive either finasteride (33 pts.) at 5 mg/day or placebo (31 pts.) for 24 months. Altogether 12 patients dropped out at some stage, and the final analysis hence included 27 patients in the finasteride group and 25 patients in the placebo group. RESULTS: The symptom scores increased by an average of 3.2 points in the finasteride group and 4.4 points in the placebo group during two years. The mean maximum flow in the finasteride group remained constant: 13.7 ml/s at baseline and 13.9 ml/s at 24 months. In the placebo group the mean maximum flow decreased from 13.3 ml/sec to 11.2 ml/s. During the two-year study period, neither of the groups displayed any changes in residual urine. The above mentioned changes were not statistically significant, however. Prostate volume and serum PSA were significantly lower in the finasteride group (p < 0.001). The groups did not differ with regard to side-effects. CONCLUSIONS: On the basis of the findings, BPH patients with moderate to severe symptoms can be treated with balloon dilatation. The effect of balloon dilatation is quick, and it alleviates the patients' symptoms immediately. Finasteride treatment maintains the positive effect of balloon dilatation. This combination of treatment is tolerated well and side-effects are rare. The favourable effect of balloon dilatation was maintained for at least two years. Finasteride treatment diminished significantly both prostate volume and serum prostate-specific antigen after balloon dilatation compared to placebo treatment.

Catheterization↗
PubMed1998

Magnetic resonance imaging of clinically localized prostatic cancer.

PURPOSE: We assess the accuracy of endorectal coil magnetic resonance imaging (MRI) for detecting tumor localization, capsular penetration and seminal vesicle invasion in clinically organ confined prostate cancer. We also evaluate intra-observer and interobserver agreement in interpreting MRI studies. MATERIALS AND METHODS: MRI studies of 51 consecutive patients a mean of 61 years old with biopsy proved prostate cancer were retrospectively read twice by 2 radiologists in random order. Both radiologists marked tumor localization, capsular penetration and seminal vesicle invasion on standard tumor maps. These findings were compared with the histopathological results of radical prostatectomy specimens. RESULTS: The overall accuracy of detecting cancer localization was 61%. The detection rate for cancer foci less than 5 mm. was only 5% but for lesions greater than 10 mm. it was 89%. There was 91 and 80% accuracy for detecting capsular penetration and seminal vesicle invasion, respectively. Sensitivity and specificity were 60 and 63, 13 and 97, and 59 and 84% for localization, capsular penetration and seminal vesicle invasion, respectively. Intra-observer and interobserver agreement ranged from fair to good (kappa coefficient 0.240 to 0.647). CONCLUSIONS: Endorectal MRI seems to be better than previously reported for detecting seminal vesicle invasion and tumor foci in the anterior half of the prostate. Sensitivity in detecting minor capsular penetration of the tumor was low, which can probably be improved by methodological development. MRI may be useful for locating cancer foci in patients with high prostate specific antigen values but repeatedly negative biopsy findings.

Aged↗
PubMed1997

Radioiodinated estramustine phosphate and estramustine binding protein antibody accumulate in the prostate of a mouse.

BACKGROUND: The purpose of this study was to determine the distribution of radioiodinated estramustine (RI-EMP) and a radioiodinated antibody against estramustine binding protein (RI-EMBP-AB) in mice. METHODS: RI-EMP and RI-EMBP-AB were injected in male mice intravenously, and the activities of tissue samples were measured 1-31 hr from the injection. Pure iodine-125 (RI) was used as a control. RESULTS: RI-EMP accumulated in the prostate, which contained 2.6% of injected activity (ID) per gram tissue at 7 hr. The liver had an activity of 21.4% ID/g at 1 hr, which decreased as RI-EMP was secreted in bile. The lung contained 2.3% ID/g at 7 hr, and it retained the activity longer than the prostate. RI-EMBP-AB accumulated in the prostate: The activity was 2.9% ID/g at 7 hr. The gallbladder contained 6.5% ID/g at 7 hr. CONCLUSIONS: Due to its cytotoxic and radiosensitizing properties, RI-EMP can possibly be used for treating prostate cancer and other tumors.

Animals↗
PubMed1997

The biodegradable self-reinforced poly-DL-lactic acid spiral stent compared with a suprapubic catheter in the treatment of post-operative urinary retention after visual laser ablation of the prostate.

OBJECTIVE: To evaluate the efficacy and safety of a biodegradable self-reinforced poly-DL-lactic acid (SR-PLA) spiral stent compared with a suprapubic catheter after visual laser ablation of the prostate (VLAP) in a randomized study. PATIENTS AND METHODS: The study comprised 45 patients (mean age 67.6 years, range 52-81) with bladder outlet obstruction caused by benign prostatic hyperplasia who received either a SR-PLA stent (22 patients) and a suprapubic catheter, or a suprapubic catheter only (23 patients) after undergoing VLAP. The suprapubic catheter was removed when voiding started. The response to VLAP and the effect of the stent or catheter were assessed using symptom scores, peak flow rate (Qmax), post-void residual volume (PVR), stent degradation, infection and outcome. RESULTS: Voiding started on the first or second day after treatment in 18 (median one day) of 22 patients with a spiral stent and in eight (median 6 days) of 23 patients with only the suprapubic catheter. The mean degradation time of the SR-PLA stent was 6 months; spiral fragments were found in the prostatic urethra or the urinary bladder in 20 of the patients on cystoscopy. Improvements in patient-weighted symptom score, mean Qmax and PVR were significant in both groups at the 6 month follow-up. The infection rate increased with the duration of suprapubic catheterization, from 25% (0-3 days) to 44% (> 3 days). Stones were seen in two stented patients during the follow-up. CONCLUSION: The SR-PLA spiral stent is safe and effective for the treatment of post-operative urinary retention after laser therapy. The degradation time of the stent was unnecessarily long compared with the duration of prostatic swelling and tissue sloughing after laser therapy. The infection rate depends on the duration of suprapubic catheterization.

Aged↗
PubMed1997

Effects of biodegradable self-reinforced polyglycolic acid, poly-DL-lactic acid and stainless-steel spiral stents on uroepithelium after Nd:YAG laser irradiation of the canine prostate.

OBJECTIVE: To evaluate the safety and tissue effects on canine uroepithelium and prostate of biodegradable self-reinforced polyglycolic acid (SR-PGA) and self-reinforced poly-DL-lactic acid (SR-PLA) spiral stents compared to stainless-steel (SS) spiral stents. MATERIAL AND METHODS: Twenty-five dogs (median body weight 12 kg) underwent a one-stage midline laparotomy and cystotomy. A side-firing Nd:YAG laser fibre was placed in the prostatic urethra antegradely and laser power applied at a setting of 20 W for 10 s in each side lobe, followed by dilatation to 4 mm diameter and insertion of a spiral stent. Dogs were randomized to receive an SR-PGA, SR-PLA or SS stent and no catheter was placed post-operatively. The dogs were killed after a follow-up of 1, 3 or 6 months and the bladder, prostate and urethra removed. Routine histological sections were prepared from the bladder, prostate, the proximal urethra immediately below the prostate and the distal urethra. RESULTS: Histological examination showed a mild to moderate foreign-body reaction and an acute inflammatory reaction after 1 month in the SR-PGA and the SR-PLA groups. The tissue effect was minimal in the SR-PGA group after 6 and 12 months. The SS stent group had more fibrosis, chronic inflammation and oedema at all follow-up assessments. There were erosions of the epithelium with subepithelial oedema in the animals with the SS stent. No dysplasia was detected and some remnants of the suture material were evident in the area of the cystotomy closure. There was one stricture at the apex of prostate in the SR-PGA group at 3 months in one re-operated dog. CONCLUSION: The histopathological changes in tissues caused by SR-PGA and SR-PLA stents were generally minor and decreased during the follow-up. The biocompatibility of SR-PGA and SR-PLA stents was good when combined with Nd:YAG laser treatment of the prostate.

Animals↗
PubMed1997

A randomized study to compare biodegradable self-reinforced polyglycolic acid spiral stents to suprapubic and indwelling catheters after visual laser ablation of the prostate.

PURPOSE: A randomized controlled study was done to evaluate the efficacy of the self-reinforced polyglycolic acid spiral stent compared to a suprapubic catheter, and combined suprapubic and indwelling catheters in the prevention of urinary retention after visual laser ablation of the prostate. MATERIALS AND METHODS: We studied 72 men with benign prostatic hyperplasia who underwent placement of a suprapubic catheter and visual laser ablation of the prostate. In 27 men in group 1 the self-reinforced polyglycolic acid spiral stent was inserted into the prostatic urethra after visual laser ablation of the prostate, while 23 in group 2 received no other devices. In 22 men in group 3 an indwelling catheter was left in situ for an average of 6.5 days. RESULTS: Voiding began 1 or 2 days postoperatively in 20 of 27 patients (median 1 day) in group 1, and 8 of 23 (median 6 days) in group 2. In 16 of 22 men in group 3 voiding began 1 or 2 days (median 6) after removal of the indwelling catheter. Improvements in patient weighted symptom score, mean peak urinary flow rate and post-void residual volume were significant (p < 0.001) at 6 months of followup in all groups. The overall infection rate was 30%. CONCLUSIONS: The self-reinforced polyglycolic acid spiral stent is superior to the suprapubic catheter alone, and to combined indwelling and suprapubic catheters for the treatment of postoperative urinary retention after laser therapy, offering possibilities for shorter catheterization time.

Aged↗
PubMed1996

Renal function remains after unilateral total and contralateral partial nephrectomy: an experimental study in pigs using 99mTc-DTPA.

Twelve nephrectomies (NEs) were performed in 12 pigs (11-17 kg). Total NE was performed on the left side and partial NE on the right side (lower third of the kidney), thus two-thirds of the total kidney volume was removed. Renal function was studied with 99mTc-diethylenetriaminepentaacetic acid (DTPA) renography and serum urea and creatinine levels preoperatively, and 1 and 2 weeks postoperatively. The pigs were imaged in each session for 30 min by collecting 10-s frames from a posteroanterior (PA) view of an anaesthesized animal. The injected activity was 37 MBq. Serial blood samples were taken from the subclavian vein at 0, 1, 2, 3, 5, 15, 25, 40, 60 and 120 min (six animals) after 99mTc-DTPA injection. The DTPA disappearance rate (DDR) was determined from these samples and in other cases (six animals) a blood sample at 20 min was used. The DDR was also determined from the dynamic gamma imaging data: Regions of interest (ROI) were upper body, spleen, heart and kidneys. The ROI analysis correlated well with the blood sampling data (r = 0.97, P < 0.0001). The reference values for pig DDRs were 0.99 +/- 0.08%/min. These values were 0.71 +/- 0.08%/min at 1 week postoperatively and 0.63 +/- 0.08%/min at 2 weeks. DTPA clearance rates were preoperatively 0.53 +/- 0.06 ml/s; at 1 week postoperatively 0.41 +/- 0.06 ml/s; and at 2 weeks 0.35 +/- 0.06 ml/s. There were no significant differences pre- and postoperatively in creatinine and urea concentrations. The DTPA clearance (ml/s) and disappearance rates (%/min) when determined per kidney area (cm2) increased significantly (P < 0.001 at both 1 and 2 weeks); in 11 of 12 animals the function of the resected right kidney was higher than the split function of the whole right kidney preoperatively. Unilateral nephrectomy initiates a functional adaptation or a growth response in the contralateral kidney to compensate for the loss of a renal mass. These data also indicate that two-thirds of the kidney volume in young pigs can be removed without danger.

Adaptation, Physiological↗
PubMed1995

Biodegradable self-reinforced polyglycolic acid spiral stent in prevention of postoperative urinary retention after visual laser ablation of the prostate-laser prostatectomy.

PURPOSE: The efficacy and safety of a new biodegradable (self-reinforced polyglycolic acid) spiral stent in securing free voiding despite edema after visual laser ablation of the prostate were studied. MATERIALS AND METHODS: A biodegradable spiral stent was inserted into the prostatic urethra in 22 patients immediately after visual laser ablation of the prostate. Uroflowmetry, measurement of residual urine volume, urine culture, cystoscopy and assessment of symptomatic improvement were done before, and 1, 3 and 6 months after visual laser ablation of the prostate. RESULTS: All 22 patients voided freely on day 1 or 2 after visual laser ablation of the prostate. However, 4 patients later had urinary retention due to a short spiral or too rapid spiral degradation. Half of the patients experienced a transient decrease in flow with some obstructive symptoms at 3 weeks that lasted 1 to 2 weeks. At 4 weeks all spirals were degraded and 3 patients had a positive urine culture. The maximum flow rate increased and the residual urine volume decreased significantly concomitantly with significant symptomatic improvement. CONCLUSIONS: The self-reinforced polyglycolic acid spiral stent can effectively and safely prevent postoperative urinary retention after visual laser ablation of the prostate.

Aged↗
PubMed1995

Residual stones after percutaneous nephrolithotomy; sensitivities of different imaging methods in renal stone detection.

Kidneys of 35 renal stone patients treated with percutaneous nephrolithotomy (PNL) were examined at 12-36 months (mean 23 months) after the procedure by plain radiography (PR), conventional linear tomography (LT), computed tomography (CT), and ultrasonography (US) to find out the long-term stone-free rate as well as the accuracy of these imaging methods to detect residual or recurrent renal stones. The present series included 36 kidneys with a 56% postoperative stone-free status examined by plain radiography and a 58% one examined by linear tomography at 12-36 months. CT showed 47% and US 72% of the kidneys to be stone-free, respectively. The sensitivity of CT was superior to plain radiography (P < 0.05), linear tomography (P < 0.05) or US (P < 0.001) in the detection of residual or recurrent stones after percutaneous nephrolithotomy analyzed statistically by McNemar's test. In the same group of 35 patients, which consisted of the above 36 postoperative kidneys together with 19 contralateral kidneys, a total of 55 kidneys were evaluated by the above methods, revealing 56 stones in 31 kidneys. Of these stones 95% were detected by CT, 70% by plain radiography, 68% by linear tomography, and 32% by renal US. Of the 55 kidneys, 14 contained 20 stone fragments smaller than 3 mm, and 26 kidneys carried 43 concrements smaller than 6 mm. The sensitivities of the four imaging methods in the detection of these small fragments were as follows: plain radiography 60% and 60%, linear tomography 55% and 58%, CT 95% and 93%, and US 15% and 26%.(ABSTRACT TRUNCATED AT 250 WORDS)

Follow-Up Studies↗
PubMed1994

Partial nephrectomy with a combined CO2 and Nd:YAG laser: experimental study in pigs.

Twenty-eight partial nephrectomies were performed on nine pigs with a simultaneous, coaxial CO2-Nd:YAG laser at power settings of 20 W and 40 W, or with a steel scalpel. A vascular pedicle clamp was used without renal cooling. The time for hemostasis was 4.5 +/- 3.2 min (mean +/- SD) with the laser and 6.4 +/- 2.5 min with the steel scalpel (P = 0.064). There was no difference in the total operation time (10.4 +/- 3.5 min with the laser vs. 11.0 +/- 3.2 min with the steel scalpel, P = 0.470). The mean blood loss with the laser was 17.5 +/- 6.7 g and 22.1 +/- 15.2 g with the steel scalpel (P = 0.299). The number of ligatures needed for complete hemostasis was 2.9 +/- 2.1 with the laser and 5.0 +/- 2.3 with the steel scalpel (P = 0.011). The average thermal damage was 0.23 +/- 0.10 mm. It is concluded that the simultaneous CO2-Nd:YAG laser method can be used in partial nephrectomy and it offers better hemostasis than the conventional technique. Further studies with different power levels are needed.

Aluminum↗