Development of a rapidly computable descriptor of prostate tissue temperature during transurethral conductive heat therapy for benign prostate hyperplasia
Tóm tắt
Benign prostate hyperplasia (BPH) is a condition in older men in which the mass of tissue in the prostate gland gradually increases over the course of many years, ultimately leading to urinary outflow obstruction. Current treatment of this condition is to surgically remove the obstructing tissue. One novel alternative therapy being studied is transurethral thermocoagulation of excessive prostatic mass. In this approach, a heat-emitting catheter is placed in the prostatic urethra, and the intraprostatic segment of the catheter is heated to temperatures above 60°C for one hour. Two-dimensional cylindrical-co-ordinate computer simulations of this treatment modality were run to model resultant temperature distributions within the prostate gland and surrounding tissues. The simulations revealed that resultant tissue temperature changes were related directly to the power delivered to the catheter and inversely to the rate of blood perfusion. Further analysis of the temperature profiles produced a rapidly computable predictor of tissue temperature in the radial dimension. Using the predictor, a ‘kill radius’ around the prostatic urethra can be easily computed on-line, during treatment, from clinically available data, catheter, power and catheter temperature. The computed kill radius may serve as a useful predictor of the extent of thermal devitalisation of unwanted obstructing tissue and the long-term success of the treatment in relieving urinary outflow obstruction without surgery.
Tài liệu tham khảo
Albritton, E. C. (1952)Standard values in blood. W. B. Saunders Co., New York.
Anderson, L., Dahn, I., Nelson, C. andNorgen, A. (1967) Method for measuring prostatic blood flow with Xenon in the dog.Investigat. Urol.,5, 140–148.
Castaneda, F., Reddy, P.K., Hulbert, J. C., Lund, G., Letourneau, J. G., Wasserman, N., Hunter, D. W., Castaneda-Zuniga, W. R. andAmplatz, K. (1987) Retrograde prostatic urethroplasty with balloon catheter.Sems. in Intervent. Radiol.,4, 115–121.
Castaneda, F. (1989) Prostatic urethroplasty complications.,6, 79–81.
Cooper, T. E. andTrezek, G. J. (1971) Correlation of thermal properties of some human tissue with water content.Aerospace Med.,42, 24–27.
DeFord, J. A. (1989) On-line estimation and control of minimum tumor temperatures during interstitial brain hyperthermia. PhD Dissertation Purdue University, West Lafayette, Indiana.
DeFord, J. A., Babbs, C. F., Patel, U. H., Fearnot, N. E., Marchosky, J. A. andMoran, C. J. (1990) Accuracy and precision of computer-simulated tissue temperatures in individual human intracranial tumours treated with interstitial hyperthermia.Int. J. Hyperthermia,6, 755–770.
DeFord, J. A., Babbs, C. F., Patel, U. H., Bleyer, M. W., Marchosky, J. A. andMoran, C. J. (1991) Effective estimation and computer control of minimum tumour temperature during conductive interstitial hyperthermia.,7, 441–453.
DeFord, J. A. Babbs, C. F. andPatel, U. H. (1992) Droop: a rapidly computable descriptor of local minimum tissue temperature during conductive interstitial hyperthermia.Med. & Biol. Eng. & Comput.,30, 333–342.
Ercole, C. J. (1989) Surgical and medical therapy of benign prostatic hyperplasia.Sems. in Intervent. Radiol.,6, 97–101.
Gonzalez, J. A., Ganesh, D. L. andBolong, D. T. (1989) Prostatic urethroplasty results at William Beaumont Hospital.6, 57–60.
Haffner, J. F. andLiavag, I. (1969) Blood flow of the hyperplastic and neoplastic human prostate measured by hydrogen polarography.Scand. J. Urol. & Nephrol.,3, 271–275.
Herrera, M. A., McCullough, D., Harrison, L. andLink, K. M. (1989) Prostatic urethroplasty results at Bowman Gray School of Medicine.Sems. in Intervent. Radiol.,6, 61–64.
Hulbert, J. C. (1989) Benign prostatic hyperplasia.,6, 8–9.
Incropera, F. P. andDeWitt, D. P. (1981)Fundamentals of heat transfer. Wiley & Sons, New York.
Jain, R. K. andDudar, T. E. (1983) Microcirculatory flow response to hyperthermia (abstract). 31st Ann. Meet. Radiat. Res. Soc., San Antonio, Texas, 26 February–3 March, Abstract Ac-5, p. 8.
Kuban, D. A., El-Mahdhi, A. M., Schellhammer, P. F., andBabb, T. J., (1985), “The effect of transurethral prostatic resection on the incidence of osseous prostatic metastasis”,Cancer,56, 961–964.
Levine, E. S., Cisek, V. J., Mulvihill, M. N., andCohen, E. L. (1986), “Role of transurethral resection in dissemination of cancer of prostate”,Urology,28(3), 179–183.
Machan, L., Gill, K. P., Abel, P., Jager, H. R., Williams, G. andAllison, D. J. (1989) Prostatic urethroplasty results at the Royal Postgraduate Medical School.Sems. in Intervent. Radiol.,6, 65–71.
Mebust, W. K., Holtgrewe, H. L., Cockett, A. T. K., Peters, C. P., and the Writing Committee (1989) Transurethral prostatectomy: immediate and postoperative complications. A cooperative study of 13 participating institutions evaluating 3,885 patients.J. Urol.,141, 243–247.
Patel, U. H., DeFord, J. A. andBabbs, C. F. (1991) Computer aided design and evaluation of novel catheters for conductive interstitial hyperthermia.Med. & Biol. Eng. & Comput.,29, 25–33.
Pennes, H. H. (1948) Analysis of tissue and arterial blood temperature in the resting forearm.J. Appl. Physiol.,1, 93–122.
Sapozink, M. D., Boyd, S. D., Astrahan, M. A., Jozsef, G. andPetrovich, Z. (1990) Transurethral hyperthermia for benign prostatic hyperplasia: preliminary clinical results.J. Urol.,143, 944–950.
Strohmaier, W. L., Bichler, K. H., Fulchter, S. H. andWilbert, D. M. (1990) Local microwave hyperthermia of benign prostatic hyperplasia.144, 913–917.
Vincente, J., Chechile, G., Salvador, J. andIzquierdo, F. (1989) Long-term follow-up of patients with intraurethral prostheses.Sems. in Intervent. Radiol.,6, 82–89.