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At least 19 recordsLinked to original sources
PubMed1996

The urodynamic impact of transrectal high-intensity focused ultrasound on bladder outflow obstruction.

OBJECTIVES: The aim of this study was to determine the urodynamic impact of transrectal high-intensity focused ultrasound (HIFU), which is presently evaluated as a minimally invasive treatment option for benign prostatic hyperplasia (BPH), on bladder outflow obstruction by means of pressure flow analyses. METHODS: A total number of 30 patients suffering from symptomatic BPH underwent pressure flow studies before and after transrectal HIFU (mean time interval: 4.5 months; range: 3-6 months). In parallel, the international prostate symptom score (IPSS), free flow and postvoid residual volume were determined at regular time intervals postoperatively. RESULTS: The IPSS decreased from preoperatively 15.8 +/- 5.9 (n = 30; mean +/- SD) to 6.9 +/- 4.4 at 3 months (n = 30) and 7.2 +/- 5 at 6 months (n = 30). Within the same time period the maximum uroflow (Qmax; ml/s) increased from 8.8 +/- 2.2 to 11.3 +/- 3.4 (3 months) and 12.1 +/- 3.6 (6 months) and the postvoid residual volume (ml) declined from 100 +/- 47 to 44 +/- 33 and 55 +/- 50, respectively. Pressure flow studies revealed a reduction of the minimal voiding pressure (cm H2O) from preoperatively 70 +/- 23 (mean +/- SD) to 51 +/- 22 (p < 0.005) postoperatively and a decline of the detrusor pressure at maximum flow (cm H2O) from 74.2 +/- 24 to 57 +/- 15 (p < 0.005). The linear passive urethral resistance relations (linear PURR) dropped from 3.7 +/- 1.1 to 2.2 +/- 1.2 (p < 0.005). According to the Abrams-Griffiths nomogram, 24 (80%) patients were classified preoperatively as obstructed, the remaining 20% as being in equivocal zone. Postoperatively, 13% were obstructed, 50% in the equivocal zone and 37% of patients were rated as obstructed. CONCLUSION: Transrectal HIFU is capable of improving objective and subjective BPH parameters as well as of decreasing the degree of bladder outflow obstruction.

Aged↗
PubMed1999

Transrectal high-intensity focused ultrasound using the Ablatherm device in the treatment of localized prostate carcinoma.

OBJECTIVES: High-intensity focused ultrasound (HIFU) consists of focused ultrasound waves emitted from a transducer that are capable of inducing tissue damage. The histologic effects and clinical outcome of the HIFU treatment were studied in two different groups of men with prostate carcinoma. METHODS: The HIFU treatment was performed under regional or general anesthesia with the Ablatherm device. In one group, HIFU was performed 7 to 12 days before radical prostatectomy, and meticulous histopathologic examination of the radical prostatectomy specimens was performed. The second group consisted of patients with localized prostate carcinoma for whom radical prostatectomy was not an option and who received HIFU treatment alone. RESULTS: In 14 patients treated with HIFU before radical prostatectomy, complete necrosis was seen in the treated region in all cases. On the dorsal border, however, incomplete destruction of tissue was noted, and in 4 cases a small vital tumor focus was seen. In the second group, of those patients in whom the entire prostate was treated, a negative biopsy result and a prostate-specific antigen (PSA) level less than 4 ng/mL was obtained in 60% and a PSA nadir less than 0.5 ng/mL in 55% of patients. CONCLUSIONS: HIFU treatment results in the two groups clearly demonstrate the potential of this modality in the treatment of localized prostate carcinoma. This study showed that extensive coagulative necrosis can be obtained in the treated areas; however, exact targeting is crucial and a prerequisite for extended clinical application of HIFU.

Aged↗
PubMed1995

Effect of high-intensity focused ultrasound on human prostate cancer in vivo.

Transrectal high-intensity focused ultrasound (HIFU) was recently established as a highly effective means of inducing contact and irradiation-free intraprostatic coagulative necrosis. This technique, therefore, appears potentially useful for treating localized prostate cancer (PC). To evaluate this issue, a total of 29 human prostates with localized cancer was subjected to HIFU treatment in vivo before radical retropubic prostatectomy. HIFU therapy was performed with the use of HIFU transducers with focal lengths of 3.0 cm (n = 3), 3.5 cm (n = 19), and 4.0 cm (n = 7), and the site intensity was varied from 1260 to 2000 W/cm2. The extent of intraprostatic necrosis was determined by planimetrical analysis of whole mount prostatic sections. Transrectal HIFU consistently induced sharply delineated intraprostatic coagulative necrosis within the target area, whereas alterations of perioprostatic structures were never observed. The cross-sectional area of necrosis increased from 1.1 +/- 0.7 cm2 (SD; n = 3; 3.0-cm focal length; 1428 W/cm2) to 1.2 +/- 0.7 cm2 (n = 2; 3.5-cm focal length; 1428 W/cm2), 1.8 +/- 0.17 cm2 (n = 8; 3.5-cm focal length; 1680 W/cm2), 2.8 +/- 0.32 cm2 (n = 9; 3.5-cm focal length; 2000 W/cm2) and 3.8 +/- 0.4 cm2 (n = 7; 4.0 cm focal length; 1260 W/cm2). HIFU beam transmission and the therapeutic effect were comparable in benign and malignant prostatic tissue. Interstitial thermometry (n = 6) revealed maximum intraprostatic temperatures in the focal zone up to 98.6 degrees C. Outside the focal zone and on the rectal wall, no significant temperature rises were noted. Subsequently, HIFU was applied to unilateral histologically proven T2a/T2b PC (n = 10) in an attempt to destroy all cancer before radical retropubic prostatectomy. PC was always correctly targeted. In 7 individuals, PC was partially (mean, 53%; range, 38-77%) destroyed; in the remaining 3 cases the entire tumor was ablated. Although these histological data permit no definitive conclusion on the clinical efficacy of this approach, transrectal HIFU seems to be an attractive novel minimally invasive treatment option for localized PC.

Aged↗
PubMed1993

Production of prostatic lesions in canines using transrectally administered high-intensity focused ultrasound.

High-intensity focused ultrasound is a method of destroying tissue at a point distant from the transducer without injuring intervening tissue. A transrectal probe was developed and used to treat 26 canines in order to determine the feasibility of using this therapy in humans. Lesions of coagulative necrosis which evolved into cystic cavities were produced. Surrounding tissue was preserved without evidence of injury.

Animals↗
PubMed1998

Clinical outcome of high-intensity focused ultrasound for treating benign prostatic hyperplasia: preliminary report.

OBJECTIVES: To preliminarily summarize the clinical outcomes of the transrectal high-intensity focused ultrasound procedure using the prototype Sonablate (HIFU1) and the new Sonablate-200 (HIFU2) for treating symptomatic benign prostatic hyperplasia. METHODS: We treated 35 and 22 patients with HIFU1 and HIFU2, respectively. Preoperative and postoperative evaluations were made using the International Prostate Symptom Score (IPSS), quality of life (QOL) data, and the results of uroflowmetry and transrectal ultrasound, and any complications were noted. RESULTS: IPSS and QOL scores showed significant improvement after using both HIFU1 and HIFU2 at 3, 6, and 12 months, postoperatively (P < 0.0001 to < 0.01; Wilcoxon signed-ranks test). Maximum flow rate (8.9 to 15.5 mL/s, P < 0.001) and prostatic volume (32.2 to 22.8 mL, P < 0.01) were significantly improved at 12 months postoperatively in patients who underwent HIFU2 treatment but not in patients who underwent HIFU1. Two hematospermia and one gross hematuria in patients treated with HIFU1 and one epididymitis in a patient treated with HIFU2 were seen but no severe complications were noted. CONCLUSIONS: Focused ultrasound is an effective new technology by which tissue can be destroyed at a site distant from the source of energy without damaging surrounding tissue. The clinical efficacy of HIFU2 was superior to that of the prototype HIFU1.

Aged↗
PubMed1998

[Preliminary results of the treatment of 44 patients with localized cancer of the prostate using transrectal focused ultrasound].

OBJECTIVE: To evaluate the efficacy and morbidity of treatment of localized prostatic cancer using transrectal high-intensity focused ultrasound. MATERIAL AND METHODS: 44 patients (mean age: 72 years) with clinical stage T1 (20) or T2 (24) prostatic cancer, not eligible for radical prostatectomy, were treated by two different prototypes of the Ablatherm (Technomed Medical System). The second prototype includes several safety devices designed to reduce morbidity. 99 sessions were performed, i.e. an average of 2.25 sessions per patient: the prostate was treated in one session (5 patients), 2 sessions (26 patients), 3 sessions (10 patients), or 4 sessions (3 patients), usually under spinal anaesthesia. The mean PSA was 9.92 ng/ml and the mean prostatic weight was 37 g. RESULTS: Complications occurred in 10 (50%) of the first 20 patients treated (1993-1995): 2 recto-urethral fistulas, 2 asymptomatic rectal burns, 2 cases of stable urinary retention, 1 case of severe incontinence, 3 cases of bladder neck sclerosis, and 1 febrile urinary tract infection. In the 24 patients treated subsequently (1995-1997), complications occurred in only 4 patients (16%): 1 case of stable urinary retention, 1 febrile urinary tract infection, 1 case of bladder neck sclerosis, 1 case of stress incontinence. A complete response (repeated negative follow-up biopsies) was obtained in 27 patients (61%). The mean post-treatment PSA level in patients of this group was 1.09 +/- 1.06 and remained stable (mean follow-up: 346 days; range: 60-1250). A residual cancer was detected in 17 patients (39%). 8 patients were considered to be failures (mean post-treatment PSA: 4.8 ng/ml) and received adjuvant treatment (hormonal: 3; external radiotherapy: 5). Complementary treatment by focused ultrasound will be performed in another 9 patients, if their PSA rises above 3 ng/ml (patients of this group are symptomatic with a mean post-treatment PSA of 1.6 ng/ml). CONCLUSION: The morbidity of treatment by transrectal focused ultrasound has now been reduced. These results suggest that this new treatment can constitute a useful option for certain patients with localized cancer, not suitable for radical prostatectomy.

Adenocarcinoma↗
PubMed2000

High-intensive focused ultrasound in localized prostate cancer.

BACKGROUND AND PURPOSE: The results of the standard treatment for prostate cancer-radical prostatectomy-are not entirely satisfactory. A new local therapy, transrectal high-intensive focused ultrasound (HIFU), has been developed. We reviewed our experience with HIFU for palliation of localized prostate cancer. PATIENTS AND METHODS: Our series included 65 men with confirmed prostate cancer without detectable metastases who were not suitable candidates for radical prostatectomy. After prophylactic suprapubic cystostomy, the patients were treated using the Ablatherm version 2.32 under spinal anesthesia. The effects were monitored by serum prostate specific antigen assays, digital rectal examination, and biopsy. The mean follow-up is 10 months (range 1-18 months). RESULTS: There were no intraoperative or postoperative deaths, and there have been no deaths from prostate cancer. Residual cancer was detected in 35% of the patients in whom only biopsy-positive portions of the prostate were treated and 17% of those in whom the entire gland was treated. Retreatment was performed 1 month after the first session in these patients. The prostate volume increased an average of 30% after treatment, but by 3 months, the gland was 10% to 20% smaller than its original size. Three patients suffered complications secondary to overheating of the rectal wall or treatment too close to the external urethral sphincter. CONCLUSION: The low morbidity, minimal invasiveness, avoidance of systemic side effects, and potentially curative effect make HIFU a potentially useful option for the treatment of localized prostate cancer.

Aged↗
PubMed2000

Long-term outcome of transrectal high- intensity focused ultrasound therapy for benign prostatic hyperplasia.

OBJECTIVE: The aim of this study was to determine the long-term outcome after transrectal high-intensity focused ultrasound (HIFU) therapy for patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). METHODS: Between June 1992 and March 1995, 98 men (mean age: 66 years) with LUTS due to BPH underwent transrectal HIFU therapy at our institution, and the data of 80 patients were included in this long-term analysis. Principal inclusion criteria were a peak flow rate (Qmax) < or =15 ml/s, AUA/IPSS score > or =18 and a prostate volume < or =75 ml. Postoperatively, patients were seen at 6-month intervals with assessment of symptom score, uroflowmetry and post-void residual volume. In the present analysis, follow-up was terminated at 4 years. The mean follow-up of the study population (excluding the patients who underwent transurethral resection of the prostate, TURP, due to insufficient therapeutic response) was 41.3 months (range: 13-48 months). RESULTS: In treatment responders (HIFU only; n = 45), the symptom score decreased from preoperatively 19.6 to 8.5 (-53%) after 12 months and subsequently showed only marginal fluctuations within the 4-year study period. The Qmax increased from preoperatively 9.1 to 11.8 ml/s (+30%) after 12 months and gradually declined to 10.2 ml/s (+12%) after 4 years. 35 men (43.8%) underwent TURP due to insufficient therapeutic response during the 4-year study period. The mean time interval between HIFU therapy and TURP was 26.5+/-2.7 months (range: 1-48 months). The retreatment-free period was significantly longer for patients with a pretreatment average flow rate >5 ml/s (p = 0.05) and lower grades of urodynamically documented bladder outflow obstruction (p = 0.03). A similar trend, which did not reach statistical significance, was noted for individuals with higher Qmax and lower post-void residuals. CONCLUSIONS: These long-time data indicate that transrectal HIFU therapy for BPH, at least in its present form, did not stand the test of time, as 43.8% of patients had to undergo TURP within 4 years after initial therapy. These data underline the need for long-term studies with follow-ups over several years to reliably assess the role of less invasive treatment options for BPH.

Aged↗
PubMed1998

Regulation of heat shock protein 27 expression of prostatic cells in response to heat treatment.

BACKGROUND: The clinical value of heat-induced coagulation of prostatic tissue is evaluated as a minimally invasive treatment for patients with benign prostatic hyperplasia (BPH) and, more recently, localized prostate cancer (PC). To obtain a more detailed insight on the effect of heat on prostatic cells, heat shock protein (HSP) 27 expression of normal and malignant prostatic cells was studied. METHODS: In vitro, HSP27 expression of prostatic stromal cells and the human prostate cancer cell line LNCaP was studied by Western blotting when cultured at 37 degrees C. Subsequently, the effect of a sublethal heat shock from 43-49 degrees C for 60 min on HSP27 expression of LNCaP was determined. In vivo, HSP27 expression pattern of nine human prostates, which were treated in vivo by thermoablation with transrectal high-intensity focused ultrasound (HIFU) 3 hr-8 days prior to surgical removal, was analyzed by immunohistochemistry. Untreated BPH (n = 10) and PC (n = 7) specimens served as controls. RESULTS: Under physiologic conditions (37 degrees C), LNCaP and prostatic stromal cells expressed a 27-kD and 56-kD anti-HSP27 reactive molecule. Following sublethal cell heating, HSP27 (27 kD) expression of LNCaP increased by 3-4-fold in a temperature-dependent manner. In untreated BPH specimens (n = 10), muscle cells stained HSP27-positive in all samples, while epithelial cells (EC) were negative in 6 out of 10 specimens. At the border of the high-intensity focused ultrasound (HIFU) necrosis, increased HSP27 expression was consistently demonstrable (n = 9). HSP27 upregulation was strongest 2-3 hr after HIFU but still demonstrable after 5-8 days. In this border zone, basal and secretory EC as well as muscle cells stained strongly for HSP27. CONCLUSIONS: Benign and malignant human prostatic cells respond to heat by increased expression of HSP27 in vitro and in vivo. Transrectal HIFU therapy induces intraprostatic thermonecrosis surrounded by a zone characterized by a massive upregulation of HSP27 expression.

Cells, Cultured↗
PubMed1995

[Minimally invasive therapy of benign prostatic hyperplasia with focussed ultrasound].

To determine the morphologic impact and safety of high-intensity focused ultrasound (HIFU) administered transrectally for tissue ablation, a total of 22 prostates were treated in vivo with transrectal HIFU prior to surgical removal. Location and size of the tissue lesions correlated well with the predefined target area and revealed sharply delineated coagulative necrosis in all cases. In a subsequent phase II clinical trial the clinical effectiveness of transrectal HIFU as a minimally invasive treatment modality for patients with symptomatic benign prostatic hyperplasia (BPH; n = 50) was studied. The maximum urinary flow rate (Qmax, ml/s) increased from 8.9 +/- 0.6 (n = 50; mean +/- SEM) to 12.8 +/- 0.9 (3 months, n = 46), 11.9 +/- 0.9 (6 months, n = 44) and 12.2 +/- 1.0 (12 months, n = 32). Within the same time period, the post-voiding residual volume (ml) decreased from 113 +/- 17 (mean +/- SEM) to 47 +/- 6, 57 +/- 7, and 49 +/- 6. These data demonstrate that transrectal HIFU can induce intraprostatic coagulative necrosis. The phase-II clinical data presented in this paper reveal that transrectal HIFU is an effective and safe minimally invasive treatment option for BPH. Nevertheless, a randomised phase-III trial comparing HIFU and TURP is mandatory to define the definitive role of transrectal HIFU in BPH, and is presently planned.

Adult↗
PubMed1993

Prostatic tissue destruction by high-intensity focused ultrasound: experimentation on canine prostate.

High-intensity focused ultrasound (HIFU) has been used transrectally to induce intraprostatic coagulation necrosis lesion in the canine prostate. The device combines a firing system (power amplifier and therapy transducer) and a localization system (ultrasound scanner). Thirty-seven dogs have been treated with ultrasound intensity ranging from 720 W/cm2 to 2300 W/cm2 and shot durations ranging from 1 to 4 seconds. The threshold for focal ultrasonic lesions was determined to be 1000 W/cm2 with a 1-second shot duration. Intraprostatic lesions were obtained without any damage to the rectal wall. These lesions were homogeneous coagulation necroses and progressed first to an inflammatory fibrosis and then to sclerosis with cavity formation. Intraprostatic lesions also occurred with a combination of moderate acoustic intensity (720 W/cm2) and longer shot duration (4 seconds). The temperature reached at the focal point of the transducer was 85 degrees C. The study confirms the possibility of creating irreversible lesions in the prostatic tissue through the rectal wall. The destruction of localized prostatic cancer seems to be possible in the near future using HIFU delivered by the transrectal route.

Animals↗
PubMed1993

High-intensity focused ultrasound in the treatment of prostatic disease.

Beginning in 1987, high-intensity focused ultrasound was investigated experimentally in a canine model to determine whether or not prostate tissue could be destroyed with good aiming and control. Subsequently a transrectal probe was developed and used to treat canine prostates in a formal study to determine whether or not this technology could be used to treat human benign prostatic hypertrophy. Next, after FDA approval, 15 patients were treated at Indiana University in the fall of 1992. Both canine and human studies have shown that high-intensity focused ultrasound administered via a transrectal probe is capable of creating prostate lesions without injury to intervening and surrounding tissue.

Animals↗
PubMed1998

Transcutaneous high-intensity focused ultrasound and irradiation: an organ-preserving treatment of cancer in a solitary testis.

OBJECTIVES: The aim of this study was to determine the feasibility and safety of transcutaneous ablation of human testicular tissue by high-intensity focused ultrasound (HIFU). METHODS: Transcutaneous ablation of human testicular tissue by HIFU was performed with equipment previously developed for transrectal prostate ablation. This device utilizes a piezoceramic transducer operating at 4.0 MHz with a site-intensity of 1,600-2,000 W/cm2. To study the histological impact of transcutaneous HIFU, tests of 4 patients with prostate cancer were subjected to transcutaneous HIFU-therapy prior to scrotal orchiectomy in a phase I trial. In a phase II clinical trial, 4 patients with the typical sonographic pattern of a tumor in a solitary testis were treated with transcutaneous HIFU as a minimally invasive organ-preserving approach followed by a 6 weeks' course of prophylactic irradiation of the testis with 20 Gy. In all 4 patients, the contralateral testis had been previously removed for testis cancer. RESULTS: Histologically, HIFU-treated areas exhibited signs of cellular necrosis in all cases (n = 4). The border between viable and necrotic tissue was extremely sharp comprising only 5-7 cell layers. In the phase II clinical study, we aimed to ablate the entire cancer in a single therapeutic HIFU session. HIFU treatment was performed under general anesthesia. As negative side effects we observed a cutaneous thermolesion in 1 individual. One patient refused to undergo postoperative irradiation and developed a local failure. This patient underwent radical orchiectomy. Another patient received two cycles of chemotherapy for a single suspicious retroperitoneal lymph node diagnosed 6 months after HIFU therapy. Three patients are tumor-free with a follow-up of 16, 23 and 31 months, respectively. CONCLUSIONS: This study demonstrates the feasibility and safety of transcutaneous testicular tissue ablation by HIFU. Despite the major drawback of this technique, i.e. that no tumor histology is obtained, we believe that transcutaneous HIFU followed by irradiation has the potential to be established as a minimally invasive treatment alternative to organ-preserving surgery for tumors in a solitary testis.

Adult↗
PubMed1994

High-intensity focused ultrasound in the treatment of prostatic tissue.

OBJECTIVE: Beginning in 1987, high-intensity focused ultrasound was investigated in the canine model to determine the feasibility of destroying prostate tissue. After demonstrating the ability to ablate prostate tissue reliably in a canine model, a 15-patient pilot clinical study was undertaken at Indiana University in the fall of 1992. This pilot study was undertaken to assess the safety in the human clinical situation, as well as to give some early efficacy results. METHODS: The early canine feasibility studies were conducted via a suprapubic extracorporeal approach using two separate transducers, one for imaging and the other for therapy. Subsequent to this, a transrectal probe, which had the dual capability of both imaging and therapy, was developed and used to treat canine prostates in a formal, "good laboratory practice" study to determine the safety of this technology prior to beginning treatment of human benign prostatic hypertrophy. RESULTS: The formal canine studies demonstrated that prostatic tissue could be reliably ablated in the therapy zone. The dosimetry and duty cycle required to ablate canine prostatic tissue effectively was also determined in this study. The study also demonstrated that the prostatic tissue could be ablated without injury to the intervening rectal tissue or periprostatic tissue. The human pilot study has also demonstrated safety of high-intensity focused ultrasound, as well as early efficacy. CONCLUSIONS: These early clinical results are encouraging, but assessment of efficacy will require a randomized study comparing high-intensity focused ultrasound to sham and to transurethral prostatectomy. This multicenter trial is currently planned.

Animals↗
PubMed1997

High-intensity focused ultrasound in the treatment of benign prostatic hyperplasia.

OBJECTIVE: To assess the role of high-intensity focused ultrasound (HIFU) in the treatment of symptomatic benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: Thirteen patients (mean age 65 years, range 58-74) were treated with HIFU as part of a phase-2 clinical trial and evaluated prospectively using the International Prostate Symptom Score, uroflowmetry, and transrectal and transabdominal ultrasonography to determine prostate size and post-void residual urine volume, respectively. The results and the patients' satisfaction were assessed at regular intervals for 2 years. RESULTS: The new procedure was learned quickly and was easy to perform. Symptom scores decreased from a mean of 23 before treatment to 5 after 12 months and 7 after 2 years. There was an initial improvement in flow rates but they then declined. The size of the prostate and the post-void residual volume were both decreased after treatment. CONCLUSIONS: The treatment is safe, easy to implement and was effective in substantially reducing symptom scores in these few patients. However, we would not encourage its use as an alternative to other well established treatment modalities until it has been assessed fully in a randomized trial.

Aged↗
PubMed1996

Noninvasive ultrasonic subtotal ablation of the prostate in dogs.

OBJECTIVE: To determine whether high-intensity focused ultrasound (HIFU) can be used for subtotal ablation of the prostate gland in dogs without causing damage to surrounding tissues. DESIGN: Experimental trial. ANIMALS: Adult hounds > or = 5 years old and weighing between 20 and 30 kg. PROCEDURE: Prostatic ablation was performed in all dogs, using a transrectal HIFU probe. Acute effects of HIFU treatment were evaluated in 4 dogs. These dogs were euthanatized and necropsied 4 hours after the procedure. Chronic effects were evaluated in the other 3 dogs. Serial CBC, serum biochemical analyses, urinalyses, and transrectal ultrasonography were performed. Dogs were euthanatized and necropsied 3 months (1 dog) or 1 year (2 dogs) after HIFU treatment. RESULTS: Histologic examination of the prostate glands from the 4 dogs euthanatized 4 hours after treatment revealed that 80 to 90% of the gland had undergone hemorrhagic, liquefactive necrosis. Only slight discoloration of the prostatic capsule was detected, and there were not any gross or histologic lesions of the rectal mucosa or urinary bladder. All 3 dogs followed up after HIFU treatment developed cystic cavities within the prostate. Clinicopathologic testing did not indicate any long-term adverse effects. CONCLUSIONS AND CLINICAL RELEVANCE: This method was effective in causing subtotal ablation of prostatic tissue in dogs. Further study of morbidity is required before the technique can be used clinically.

Animals↗
PubMed1993

High-intensity focused ultrasound experimentation on human benign prostatic hypertrophy.

High intensity-focused ultrasound (HIFU) has been used transrectally to induce an intraprostatic coagulation necrosis lesion in human prostatic adenoma. The device to produce HIFU combines a firing system (power amplifier and therapy transducer) and an imaging system (ultrasound scanner). Nine patients have been treated on epidural anaesthesia with an ultrasound intensity similar to or higher than the acoustic intensity used in previous experiments on canine prostates. Intraprostatic lesions were obtained without any damage to the rectal wall. These lesions were also histologically determined to be coagulation necrosis with a complete destruction of the glandular tissue. These studies confirm the possibility of creating irreversible lesions in the prostatic tissue through the rectal wall. The destruction of localised prostatic cancer would seem to be possible in the near future by using HIFU delivered by the transrectal route.

Humans↗