title: Feasibility of photoacoustic evaluations on dual-thermal treatment of ex vivo bladder tumors.
abstract: A variety of thermal therapeutic methods have been investigated to treat bladder tumors but often cause bowel injury and bladder wall perforation due to high treatment dosage and limited clinical margins. The objective of the current study is to develop a dual-thermal modality to deeply coagulate the bladder tumors at low thermal dosage and to evaluate therapeutic outcomes with high contrast photoacoustic imaging (PAI). High intensity focused ultrasound (HIFU) is combined with 532 nm laser light to enhance therapeutic depth during thermal treatments on artificial tumor-injected bladder tissue ex vivo. PAI is employed to identify the margins of the tumors pre- and post-treatments. The dual-thermal modality achieves 3- and 1.8-fold higher transient temperature changes and 2.2- and 1.5-fold deeper tissue denaturation than laser and HIFU, respectively. PAI vividly identifies the position of the injected tumor and entails approximately 7.9 times higher image contrast from the coagulated tumor as that from the untreated tumor. Spectroscopic analysis exhibits that both 740 nm and 760 nm attains the maximum photoacoustic amplitudes from the treated areas. The proposed PAI-guided dual-thermal treatments (laser and HIFU) treatments can be a feasible therapeutic modality to treat bladder tumors in a controlled and efficient manner.
authors.affiliation: Interdisciplinary Program of Biomedical Mechanical & Electrical Engineering, Pukyong National University, Busan, 608-737, South Korea.
authors.forename: Van Phuc
authors.initials: VP
authors.lastname: Nguyen
authors.affiliation: Interdisciplinary Program of Biomedical Mechanical & Electrical Engineering, Pukyong National University, Busan, 608-737, South Korea.|Department of Biomedical Engineering and Center for Marine-Integrated Biomedical Technology (BK 21 Plus), Pukyong National University, Busan, 608-737, South Korea.
authors.forename: Junghwan
authors.initials: J
authors.lastname: Oh
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics, Suwon, 443-803, South Korea.
authors.forename: Suhyun
authors.initials: S
authors.lastname: Park
authors.affiliation: Interdisciplinary Program of Biomedical Mechanical & Electrical Engineering, Pukyong National University, Busan, 608-737, South Korea.|Department of Biomedical Engineering and Center for Marine-Integrated Biomedical Technology (BK 21 Plus), Pukyong National University, Busan, 608-737, South Korea.
authors.forename: Hyun
authors.initials: H
authors.lastname: Wook Kang
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D057086:High-Intensity Focused Ultrasound Ablation; D066298:In Vitro Techniques; D007834:Lasers; D008954:Models, Biological; D061088:Photoacoustic Techniques / Q000379:methods; D013057:Spectrum Analysis; D013552:Swine; D013696:Temperature; D013997:Time Factors; D001743:Urinary Bladder / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology / Q000628:therapy*
keywords: Bladder tumors; HIFU; dual-thermal treatments; laser treatments; photoacoustic imaging