title: Hybrid-modality ocular imaging using a clinical ultrasound system and nanosecond pulsed laser.
abstract: Hybrid optical modality imaging is a special type of multimodality imaging significantly used in the recent past in order to harness the strengths of different imaging methods as well as to furnish complementary information beyond that provided by any individual method. We present a hybrid-modality imaging system based on a commercial clinical ultrasound imaging (USI) system using a linear array ultrasound transducer (UST) and a tunable nanosecond pulsed laser as the source. The integrated system uses photoacoustic imaging (PAI) and USI for ocular imaging to provide the complementary absorption and structural information of the eye. In this system, B-mode images from PAI and USI are acquired at 10 Hz and about 40 Hz, respectively. A linear array UST makes the system much faster compared to other ocular imaging systems using a single-element UST to form B-mode images. The results show that the proposed instrumentation is able to incorporate PAI and USI in a single setup. The feasibility and efficiency of this developed probe system was illustrated by using enucleated pig eyes as test samples. It was demonstrated that PAI could successfully capture photoacoustic signals from the iris, anterior lens surface, and posterior pole, while USI could accomplish the mapping of the eye to reveal the structures like the cornea, anterior chamber, lens, iris, and posterior pole. This system and the proposed methodology are expected to enable ocular disease diagnostic applications and can be used as a preclinical imaging system.
authors.affiliation: Nanyang Technological University , Centre for Optical and Laser Engineering, School of Mechanical and Aerospace Engineering, 50 Nanyang Avenue, Singapore 639798, Singapore.
authors.forename: Hoong-Ta
authors.initials: HT
authors.lastname: Lim
authors.affiliation: Nanyang Technological University , Centre for Optical and Laser Engineering, School of Mechanical and Aerospace Engineering, 50 Nanyang Avenue, Singapore 639798, Singapore.
authors.forename: Murukeshan Vadakke
authors.initials: MV
authors.lastname: Matham
keywords: hybrid-modality imaging; ocular imaging; photoacoustic imaging; ultrasound imaging
references.citation: Echocardiography. 2001 May;18(4):355-61
references.pmid: 11415509
references.citation: Clin Exp Ophthalmol. 2004 Dec;32(6):639-47
references.pmid: 15575836
references.citation: IEEE Trans Med Imaging. 2005 Apr;24(4):436-40
references.pmid: 15822801
references.citation: Exp Eye Res. 2005 Nov;81(5):561-9
references.pmid: 15949799
references.citation: Nat Biotechnol. 2006 Jul;24(7):848-51
references.pmid: 16823374
references.citation: J Nucl Med. 2008 Feb;49(2):169-72
references.pmid: 18199608
references.citation: Opt Express. 2008 Oct 13;16(21):16284-93
references.pmid: 18852734
references.citation: Med Phys. 2008 Dec;35(12):5758-67
references.pmid: 19175133
references.citation: Acta Ophthalmol. 2009 Nov;87(8):917-9
references.pmid: 19416107
references.citation: Opt Lett. 2010 Feb 1;35(3):270-2
references.pmid: 20125691
references.citation: Nat Photonics. 2009 Aug 29;3(9):503-509
references.pmid: 20161535
references.citation: Ultrasound Med Biol. 2010 May;36(5):733-42
references.pmid: 20420969
references.citation: Trends Biotechnol. 2011 May;29(5):213-21
references.pmid: 21324541
references.citation: Cell. 2011 Mar 4;144(5):646-74
references.pmid: 21376230
references.citation: Science. 2012 Mar 23;335(6075):1458-62
references.pmid: 22442475
references.citation: Opt Lett. 2012 Apr 1;37(7):1244-6
references.pmid: 22466209
references.citation: Nat Med. 2012 Aug;18(8):1297-1302
references.pmid: 22797808
references.citation: J Biomed Opt. 2012 Jul;17(7):076012
references.pmid: 22894495
references.citation: Sci Rep. 2014 Oct 06;4:6525
references.pmid: 25283870
references.citation: Photoacoustics. 2013 Aug 28;1(2):36-42
references.pmid: 25302148
references.citation: Health Phys. 2013 Sep;105(3):271-295
references.pmid: 30522251