High-intensity focussed ultrasound (HIFU) treatment in uraemic secondary hyperparathyroidism

Abstract Purpose In this study, the robustness and feasibility of a noise elimination method using continuous wave response of therapeutic ultrasound signals were investigated when tissue samples were moved to simulate the respiration-induced movements of the different organs during actual high-intensity focused ultrasound (HIFU) treatment. In addition to that, the failure conditions of the proposed algorithm were also investigated. Methods The proposed method was applied to cases where tissue samples were moved along both the lateral and axial directions of the HIFU transducer to simulate respiration-induced motions during HIFU treatment, and the noise reduction level was investigated. In this experiment, the speed of movement was increased from 10 to 40 mm/s to simulate the actual movement of the tissue during HIFU exposure, with the intensity and driving frequency of HIFU set to 1.0–5.0 kW/cm2 and 1.67 MHz, respectively. To investigate the failure conditions of the proposed algorithm, the proposed method was applied with the HIFU focus located at the boundary between the phantom and water to easily cause cavitation bubbles. The intensity of HIFU was set to 10 kW/cm2. Results Almost all HIFU noise was constantly able to be eliminated using the proposed method when the phantom was moved along the lateral and axial directions during HIFU exposure. The noise reduction level (PRL in this study) at an intensity of 1.0, 3.0, and 5.0 kW/cm2 was in the range of 28–32, 38–40, and 42–45 dB, respectively. On the other hand, HIFU noise was not basically eliminated during HIFU exposure after applying the proposed method in the case of cavitation generation at the HIFU focus. Conclusions The proposed method can be applicable even if homogeneous tissues or organs move axially or laterally to the direction of HIFU exposure because of breathing. A condition under which the proposed algorithm failed was when instantaneous tissue changes such as cavitation bubble generation occurred in the tissue, at which time the reflected continuous wave response became less steady.

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High-Intensity Focused Ultrasound Treatment for Advanced Pancreatic Cancer

Gastroenterology Research and Practice ◽

10.1155/2014/205325 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 20

Author(s):

Yufeng Zhou

Keyword(s):

Pancreatic Cancer ◽

High Intensity ◽

Focused Ultrasound ◽

Advanced Pancreatic Cancer ◽

High Intensity Focused Ultrasound ◽

Treatment Modalities ◽

Karnofsky Performance Scale ◽

Great Success ◽

Hifu Treatment ◽

Performance Scale

Pancreatic cancer is under high mortality but has few effective treatment modalities. High-intensity focused ultrasound (HIFU) is becoming an emerging approach of noninvasively ablating solid tumor in clinics. A variety of solid tumors have been tried on thousands of patients in the last fifteen years with great success. The principle, mechanism, and clinical outcome of HIFU were introduced first. All 3022 clinical cases of HIFU treatment for the advanced pancreatic cancer alone or in combination with chemotherapy or radiotherapy in 241 published papers were reviewed and summarized for its efficacy, pain relief, clinical benefit rate, survival, Karnofsky performance scale (KPS) score, changes in tumor size, occurrence of echogenicity, serum level, diagnostic assessment of outcome, and associated complications. Immune response induced by HIFU ablation may become an effective way of cancer treatment. Comments for a better outcome and current challenges of HIFU technology are also covered.

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High-intensity focussed ultrasound (HIFU) als salvagebehandeling van recidiverend prostaatcarcinoom: stand van zaken wetenschap en praktijk. Een review van systematische reviews

Tijdschrift voor Urologie ◽

10.1007/s13629-020-00291-x ◽

2020 ◽

Vol 10 (8) ◽

pp. 156-164

Author(s):

Valery E. P. P. Lemmens ◽

Olav G. J. M. van Aubel

Keyword(s):

High Intensity ◽

Kwaliteit Van Leven ◽

Salvage Hifu ◽

Focussed Ultrasound

SamenvattingEr verschijnen steeds meer oorspronkelijke studies naar de veiligheid en effectiviteit van HIFU als salvagebehandeling van een lokaal recidief van het prostaatcarcinoom (Pca). Ook verschenen recentelijk meerdere systematische reviews (SR’s) over dit onderwerp. Deze review van SR’s geeft inzicht in de huidige stand van wetenschap en praktijk ten aanzien van salvage-HIFU van een lokaal recidiverend Pca. De meest recente en tevens grootste SR toont bij een lokaal recidief na bestraling geen verschil in overleving tussen HIFU en salvage radicale prostatectomie of salvagebestraling. De morbiditeit na salvage-HIFU was lager dan na een salvage radicale prostatectomie. In verband met de hoge morbiditeit bij een salvage radicale prostatectomie wordt deze zelden uitgevoerd. HIFU als salvagebehandeling kan daarom worden gezien als een veelbelovend alternatief. Dit geldt zeker voor patiëntengroepen bij wie leeftijd, ziektestadium en wens van de patiënt in de richting wijzen van afzien van agressievere therapieën, en bij wie het risico op bijwerkingen en vermindering van de kwaliteit van leven te hoog wordt geacht. De huidige evidence geeft voldoende aanleiding om, in afwachting van studies met hogere bewijskracht, HIFU als salvagebehandeling aan te bieden in plaats van androgeendeprivatietherapie, dan wel niet te behandelen.

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