Novel application of three-dimensional shear wave elastography in the detection of clinically significant prostate cancer.

The present study evaluated three-dimensional shear wave elastography (3D SWE) in the detection of clinically significant prostate cancer. Clinically significant prostate cancer was defined by a minimum of one biopsy core with a Gleason score of 3+4 or 6 with a maximum cancer core length >4 mm. Patients with serum prostate-specific antigen levels of 4.0-20.0 ng/ml who were suspected of having prostate cancer from multi-parametric magnetic resonance imaging (mpMRI) were prospectively recruited. The 3D SWE was performed pre-biopsy, after which patients underwent MRI-transrectal ultrasound image-guided targeted biopsies for cancer-suspicious lesions and 12-core systematic biopsies. The pathological biopsy results were compared with the mpMRI and 3D SWE images. A total of 12 patients who were suspected of having significant cancer on mpMRI were included. The median pre-biopsy PSA value was 5.65 ng/ml. Of the 12 patients, 10 patients were diagnosed as having prostate cancer. In the targeted biopsy lesions, there was a significant difference in Young's modulus between the cancer-detected area (median 64.1 kPa, n=20) and undetected area (median 30.8 kPa, n=8; P<0.0001). On evaluation of receiver operating characteristics, a cut-off value of the Young's modulus of 41.0 kPa was used for the detection of clinically significant cancer, with which the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of cancer detection were 58, 97, 86 and 87%, respectively. When combining this cut-off tissue elasticity value with Prostate Imaging Reporting and Data System (PI-RADS) scores, the sensitivity, specificity, positive predictive value and negative predictive value of cancer detection were improved to 70, 98, 91 and 92%, respectively. In the cancer-detected lesions, a significant correlation was identified between the tissue elasticity value of the lesions and Gleason score (r=0.898, P<0.0001). In conclusion, PI-RADS combined with measurement of Young's modulus by 3D SWE may improve the diagnosis of clinically significant prostate cancer.

Urethra-sparing high-intensity focused ultrasound for localized prostate cancer: Functional and oncological outcomes.

OBJECTIVES: To evaluate longitudinal changes in urinary function and quality of life, and the oncological outcomes of patients treated with urethra-sparing high-intensity focused ultrasound for localized prostate cancer. METHODS: Patients with negative findings in the urethra and the anterior urethral zone using transrectal ultrasound-guided targeted biopsies, and magnetic resonance imaging, received urethra-sparing or whole-gland high-intensity focused ultrasound as the primary therapy for localized prostate cancer without transurethral resection of the prostate. Longitudinal changes in urinary function and quality of life, and the oncological outcomes of the patients were analyzed retrospectively. RESULTS: The median follow-up times for urethra-sparing and whole-gland high-intensity focused ultrasound were 36 and 30 months, respectively. Comparing the patients treated with urethra-sparing high-intensity focused ultrasound (n = 45) with those treated with whole-gland high-intensity focused ultrasound (n = 65), there were significant differences in the International Prostate Symptom Score (P = 0.014) at 3 months, International Prostate Symptom Score quality of life (P = 0.033) at 3 months, maximum urinary flow rate (mL/s; at 3 months, P = 0.010; at 6 months, P = 0.038) and residual urine volume (mL; at 3 months, P < 0.0001; at 6 months, P = 0.016; at 12 months, P = 0.028). For quality of life, there were significant differences in Functional Assessment of Cancer Therapy - General (at 3 months, P = 0.022) and Functional Assessment of Cancer Therapy - Prostate (at 3 months, P = 0.028; at 6 months, P = 0.034). There were no significant differences in oncological outcomes regarding negative biopsy rates on follow up (91% vs 92%; P = 0.8) or biochemical disease-free survival rates (86.7% vs 89.2%; P = 0.7). CONCLUSIONS: Urethra-sparing high-intensity focused ultrasound might prevent prolonged bladder outlet obstruction, and could be a treatment option for localized prostate cancer.

Morphological analysis of the effects of intraoperative transrectal compression of the prostate during high-intensity focused ultrasound for localized prostate cancer.

OBJECTIVES: To evaluate the effects of transrectal compression of the prostate for intra-operative prostatic swelling and intraprostatic point shift during high-intensity focused ultrasound treatment of localized prostate cancer. METHODS: Patients treated with whole-gland high-intensity focused ultrasound as primary monotherapy for localized prostate cancer were enrolled in the study. Using the standard and compression method, the volumes of degassed water in the balloon covering the high-intensity focused ultrasound probe were 50 mL and 80-160 mL, respectively. To identify prostatic swelling and shift during high-intensity focused ultrasound and the volume occupied by the non-enhanced area, three-dimensional prostate models were reconstructed using ultrasound and contrast-enhanced magnetic resonance imaging. RESULTS: In comparison with the standard (n = 40) and compression (n = 48) methods, intraoperative increase in the prostate volume (21% vs 5.3%; P = 0.044), intraprostatic point shift (4 mm vs 2 mm, P = 0.040 in the transition zone; 3 mm vs 0 mm; P = 0.001 in the peripheral zone) and the volume occupied by the non-enhanced area (89% vs 96%; P = 0.001) were significantly suppressed. The biochemical disease-free survival rate in patients treated using the compression method was significantly improved relative to the standard method (92.6% vs 76.5%; P = 0.038). Regarding complications, there was no significant difference in the rate of urethral stricture (P = 0.9), urinary tract infection (P = 0.9), incontinence (P = 0.3), erectile dysfunction (P = 0.9) or recto-urethral fistula between the patients treated using the standard and compression methods. CONCLUSIONS: Intraoperative transrectal compression suppresses intraoperative increase in the prostate volume and intraprostatic point shift during high-intensity focused ultrasound, having the potential to achieve precise whole-gland and lesion-targeted focal therapy.

Time-dependent change of blood flow in the prostate treated with high-intensity focused ultrasound.

Avascular areas on contrast-enhanced magnetic resonance imaging have been considered to be areas of localized prostate cancer successfully treated by high-intensity focused ultrasound. However, the optimal timing of magnetic resonance imaging has not been discussed. The thermal effect of high-intensity focused ultrasound is degraded by regional prostatic blood flow. Conversely, the mechanical effect of high-intensity focused ultrasound (cavitation) is not affected by blood flow, and can induce vessel damage. In this series, the longitudinal change of blood flow on contrast-enhanced magnetic resonance imaging was observed from postoperative day 1 to postoperative day 14 in 10 patients treated with high-intensity focused ultrasound. The median rates of increase in the non-enhanced volume of the whole gland, transition zone and peripheral zone from postoperative day 1 to postoperative day 14 were 36%, 39%, and 34%, respectively. In another pathological analysis of the prostate tissue of 17 patients immediately after high-intensity focused ultrasound without neoadjuvant hormonal therapy, we observed diffuse coagulative degeneration and partial non-coagulative prostate tissue around arteries with vascular endothelial cell detachment. These observations on contrast-enhanced magnetic resonance imaging support a time-dependent change of the blood flow in the prostate treated with high-intensity focused ultrasound. Additionally, our pathological findings support the longitudinal changes of these magnetic resonance imaging findings. Further large-scale studies will investigate the most appropriate timing of contrast-enhanced magnetic resonance imaging for evaluation of the effectiveness of high-intensity focused ultrasound for localized prostate cancer.

[Examination of the orbitomeatal basal line-anthropological basal line crossing angle and acanthiomeatal line-anthropological basal line crossing angle].

Orbitomeatal basal line-anthropological basal line (OML-ABL), and the acanthiomeatal line (AML)-ABL crossing angles were measured using profile pictures. There were 219 volunteers in total: 42 people four years old, 44 people nine years old, 45 people 14 years old, 43 people 19 years old, and 45 people 40 years or older (48±7.4 years). The average OML-ABL crossing angle was 14.3 degrees in the 4-year-old group, while that of the 40-year or older group was 11.1 degrees. The deviation width of the 4-year-old group was 4.8 degrees, and that of the 40-year or older group was 2.4 degrees. The average AML-ABL crossing angle was 12.3 degrees in the 4-year-old group, while that of the 40-year or older group was 15.7 degrees. There were differences between males and females. The deviation width of the 4-year group was 5.4 degrees, and that of the 40-year or older group was 2.7 degrees. The results showed that 14.0 degrees for around 4-year-old, and 12.0 degrees for around 9- to 14-year-olds, could be used as OML-ABL crossing angles as a practical proposition.

[Experimental study of the influence on pacemakers of X-rays from angiocardiography equipment].

We performed an experimental study of the influence on pacemakers (PM) of X-rays from the angiocardiography equipment. (1) We used one PM of DDD mode in this study. (2) The PM was irradiated under two exposure levels: one the standard dose and the other the maximum dose in the angiocardiography study situation. (3) We set the pacing lead wires to the bilateral atria and ventricles in Irnich's human body model. (4) We set two irradiation fields, one with a lead block on the PM and the other without the lead block. The result showed that when the PM was included in the irradiation field and the exposure level was of the maximum dose, the influence of irradiation on the PM was that of level 2 as classified by a research report by the Ministry of Internal Affairs and Communications. The absorbed dose of the PM was 93.4 mGy under these conditions. We confirmed that radiation dose does not affect a pacemaker with pacing lead wire. However, it acts on the generator of the PM owing to the direct photoelectric effect. When there were many dose rates (or total radiation dose), an obstacle occurred.

[Analysis of natural medicines by micellar electrokinetic chromatography (MEKC) (II)--determination of atractylenolide III in Atractylodis Rhizoma].

We have investigated a method to analyze the marker substance of natural medicines by employing capillary electrophoretic techniques such as micellar electrokinetic chromatography (MEKC). We previously reported a simple MEKC assay method for calycosin in Astragali Radix and its fluid extract. In this investigation, we analyzed the marker substance atractylenolide III in Atractylodis Rhizoma. Atractylenolide III was clearly separated from the other components in A. Rhizoma and its dried extract by simple solvent extraction with hexane and subsequent MEKC analysis with sodium dodecyl sulfate (SDS) within 10 min. Validation of the analytical procedures of the assay method was performed according to the Japanese Pharmacopoeia and International Conference on Harmonization guidelines. As a result, we confirmed that capillary electrophoresis, including MEKC, is a powerful method for estimating the quality of natural medicines and traditional Chinese medicines consisting of various components.