Kiyotake Ichizuka1, Ryu Matsuoka2, Hiroko Aoki3, Junichi Hasegawa4, Takashi Okai5, Shin-Ichiro Umemura6. 1. Department of Obstetrics and Gynecology, Showa University Northern Yokohama Hospital, Chigasaki-chuo, Tsuzuki-ku, Yokohama, Kanagawa, 224-8503, Japan. ichizuka@med.showa-u.ac.jp. 2. Department of Obstetrics and Gynecology, Showa University, School of Medicine, Tokyo, Japan. 3. Department of Obstetrics and Gynecology, Mito Red Cross Hospital, Mito, Japan. 4. Department of Obstetrics and Gynecology, St. Marianna University, School of Medicine, Kawasaki, Japan. 5. Department of Obstetrics and Gynecology, Aiiku Hospital, Tokyo, Japan. 6. Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.
Abstract
PURPOSE: The objective of the present study was to develop a high-intensity focused ultrasound (HIFU) transducer more suitable for clinical use in fetal therapy for twin reversed arterial perfusion (TRAP) sequence. MATERIALS AND METHODS: We created a cooling and degassed water-circulating-type HIFU treatment device. HIFU was applied to renal branch vessels in three rabbits. Sequential HIFU irradiation contains a trigger wave, heating wave, and rest time. The duration of HIFU application was 10 s/course. Targeting could be achieved by setting the imaging probe in the center and placing the HIFU beam and imaging ultrasonic wave on the same axis. RESULT: We confirmed under sequential HIFU irradiation with a total intensity of 1.94 kW/cm(2) (spatial average temporal average intensity) that the vein and artery were occluded in all three rabbits. CONCLUSION: Simultaneous occluding of the veins and arteries was confirmed with trigger waves and a resting phase using the HIFU transducer treatment device created for this study. Clinical application appears possible and may represent a promising option for fetal therapy involving TRAP sequence.
PURPOSE: The objective of the present study was to develop a high-intensity focused ultrasound (HIFU) transducer more suitable for clinical use in fetal therapy for twin reversed arterial perfusion (TRAP) sequence. MATERIALS AND METHODS: We created a cooling and degassed water-circulating-type HIFU treatment device. HIFU was applied to renal branch vessels in three rabbits. Sequential HIFU irradiation contains a trigger wave, heating wave, and rest time. The duration of HIFU application was 10 s/course. Targeting could be achieved by setting the imaging probe in the center and placing the HIFU beam and imaging ultrasonic wave on the same axis. RESULT: We confirmed under sequential HIFU irradiation with a total intensity of 1.94 kW/cm(2) (spatial average temporal average intensity) that the vein and artery were occluded in all three rabbits. CONCLUSION: Simultaneous occluding of the veins and arteries was confirmed with trigger waves and a resting phase using the HIFU transducer treatment device created for this study. Clinical application appears possible and may represent a promising option for fetal therapy involving TRAP sequence.
Authors: Jeffrey C Livingston; Foong-Yen Lim; William Polzin; Jennifer Mason; Timothy M Crombleholme Journal: Am J Obstet Gynecol Date: 2007-10 Impact factor: 8.661
Authors: K Ichizuka; S Ando; M Ichihara; T Ishikawa; N Uchiyama; K Sasaki; S Umemura; R Matsuoka; A Sekizawa; T Okai; T Akabane; M Kushima Journal: Ultrasound Obstet Gynecol Date: 2007-07 Impact factor: 7.299
Authors: Hanmin Lee; Amy J Wagner; Edgar Sy; Robert Ball; Vickie A Feldstein; Ruth B Goldstein; Diana L Farmer Journal: Am J Obstet Gynecol Date: 2007-05 Impact factor: 8.661