우리는 국립 과학 재단 (National Science Foundation) (경력 CBET-1055379)과 국립 보건원 (1RC4EY021357, 1R01EY019951)에서 관대 한 지원을 감사합니다. 우리는 또한 중국 장학위원회에서 웨이의 노래를 지원을 인정합니다.

1. 시스템 구성 <ol><li> PAOM 서브 시스템 <ol><li> 조명 출처 : ND : YAG 레이저 (SPOT-10-100, Elforlight (주), 영국 : 20 μJ / 펄스, 2 nsec 펄스 지속 시간, 30 kHz에서 최대 펄스 반복 속도). </li><li> 베타 바륨-borate에 의해 532 nm의에 주파수를 두 배로 1064 nm의에서 출력 레이저가 있습니다 (BBO) 크리스탈 (CasTech, 산호세, CA). 레이저 선 거울로 더 분할 한 후, 532 nm의 광은 단일 모드 광섬유 (P1-460A-FC-5, Thorlabs)를 통해 전달하고 있으며, 1064 nm의 레이저가 트리거 포토 다이오드 (DET10A, Thorlabs)에 의해 기록됩니다 PA 신호 획득. </li><li> 단일 모드 광섬유에서 나오는 레이저 빛이 검류계 (GM, QS-7, Nutfield 기술)과 망원경을 구성하여 망막에 전달됩니다 (F1 = 75 mm와 F2 = 14mm, 에드먼드 광학) 6. </li><li> 산만 바늘 변환기 (40 MHz의 중심 주파수, 16 MHz의 대역폭, 0.4 × 0.4 mm 2 개 활성 요소의 크기, NIH 자원 Cente초음파 변환기 기술, 남부 캘리포니아 대학)에 대한 연구는 망막에서 생성 PA 신호를 감지 할 수 눈꺼풀과 접촉에 배치되어 있습니다. 초음파 젤 (Sonotech)는 좋은 음향 커플 링에 대한 변환기 팁과 동물 눈꺼풀 사이에 적용됩니다. </li><li> PA 신호는 두 앰프 (ZFL-500LN +, 미니 회로, 그리고 5073PR, 올림푸스)에 의해 증폭되고, (CS14200, 게이지가 적용) 데이터 수집 보드가 디지털화되어 있습니다. </li></ol></li><li> SD 10 월 서브 시스템 <ol><li> 낮은 일관성 광원 : 광대역 초 발광 다이오드 (IPSDD0804, InPhenix, 센터 파장 :; : 50 nm의 6 dB 대역폭 840 nm의) 6 μm의 축 해상도를 결정합니다. </li><li> 가까운 적외선 빛이 (50)에 의해 팔과 샘플 팔을 참조하도록 분할되어 × 50 사용자 정의 단일 모드 광섬유 커플러 (OZ 광학). </li><li> 뜨거운 거울 (FM02, Thorlabs)에 의해 PAOM 조명의 빛으로 결합 후, 10 월 샘플 팔이 동일한 검사 및 배달 광학 무선 인터넷 접속을 공유일 PAOM 6. </li><li> 집에서 내장 분석기는 라인 스캔 CCD 카메라 (Aviiva SM2, e2v)는 24 kHz에서의 A-라인 속도를 수있는 SD 10 월의 간섭 신호를 기록하는 데 사용됩니다. 전형적인 분석기의 설계는 몇 가지 이전에 다음 ID로 출판 인쇄물 11 섬유 결합 SD 10 월 분석기에서 찾을 수 있습니다하는 것은 현재 상업적으로 사용할 수 있습니다. SD 10 월 감도는 90dB보다 더 나은 것으로 측정됩니다. </li></ol></li><li> 계획을 스캔 <ol><li> 검류계의 검색 빠른 2-D 래스터도 PAOM 레이저 발사와 10월 분석기의 신호 인수를 모두 실행 아날로그 출력 보드 (PCI-6731, 내쇼날 인스트루먼트)에 의해 제어됩니다. 그 결과, PAOM 및 10월 서브 시스템에있는 데이터 인수가 동기화됩니다. </li><li> PAOM 데이터 수집은 포토 다이오드 기록 PAOM 레이저 순서 (1.1.2 참조)에 의해 실행됩니다. </li><li> 3-D 입체 이미지 또는 2-D fundus 이미지는 (256 256 B-스캔 이미지에서 제작 B 당 A-라인) 이미지를 스캔합니다. </li></ol></li></ol> 2. 시스템 정렬 <ol><li> BBO 크리스탈의 주파수 복제 효율과 단일 모드 광섬유의 커플 링 효율을 극대화 할 수 있습니다. PAOM 조명의 빛을 최적화 할 때 인사 눈 보호를 위해 LG3 고글 (Thorlabs)을 착용하십시오. </li><li> 직경 2.0 mm에 PAOM의 섬유 출력 레이저를 Collimate. </li><li> 동축 할 PAOM 및 SD 10 월의 결합 조명 조명을 맞 춥니 다. </li><li> ~ 0.8 MW의 빛을 프로빙 ~ 40 뉴저지 / 펄스 및 SD 10 월의 PAOM 여기 빛을 설정 둘 다 6,12 안전 눈으로보고됩니다. </li></ol> 3. 생체 Multimodal 망막 영상에서 <ol><li> 투명 폴리 프로필렌 상자에 쥐를 전송하고, isoflurane (피닉스 제약 주식회사)와 일반 1.5 %의 농도의 공기와 2.0 리터 / 10 분에 분의 유량의 혼합물에 의해 동물을 마취. </li><li> homema에 anesthetized 쥐를 구속드 다섯 축 조절 자유 (그림 1) 및 가열 패드 (Repti 칼로리, 확대 실험실, 주식회사)에 의해 ~ 37 ° C에서의 체온을 유지와 홀더. 실험을하는 동안 1.0 % 농도와 1.5 리터 / 분 유량과 혼합 isoflurane과 정상적인 공기의 흡입 가스로 마취를 유지합니다. </li><li> , 외과 가위를 사용하여 속눈썹을 잘라 1 % Tropicamide의 안과 솔루션 동공을 팽창하고, 0.5 % Tetracaine 하이드로 클로라이드의 안과 솔루션을 사용하여 홍채 괄약근 근육을 마비. 쥐 눈 각막 탈수 및 백내장 형성을 방지하기 위해 다른 모든 분에게 인공 눈물 물방울 (Systane, 앨콘 연구소 주식회사)을 적용합니다. 이미징 동안 펄스 산소 농도계 (8,600 V, Nonin 의료, MN)에 의해 동물 심장 박동, 호흡, 혈액의 산소를 모니터링합니다. </li><li> SD 10 월 조명 라이트를 켜고 ~ 0.8 MW 될 수있는 프로빙 빛을 확인합니다. </li><li> 검류계 검사를 활성화합니다. SD 10 월의 조사 광 전송을 정렬쥐 망막로하고, 5 축 동물 소유자를 조정하여 관심있는 망막 지역 (ROI)을 식별합니다. 투자 수익 (ROI)은 다른 연구 요구 사항에 따라 선택해야하는 동안 여기 광 디스크가 의도적으로, 시야의 중앙에 배치됩니다. </li><li> 또한 최고의 광학 초점에 도달 할 때까지 모두 스캔 방향 (래스터 스캐닝 방향을 전환하여)에서 망막 단면의 SD 10 월 이미징 품질을 최적화하기 위해 동물 소유자를 조정합니다. </li><li> 다섯 축 조절 플랫폼에서 바늘 변환기를 준비 변환기 팁에 초음파 젤 한 방울을 적용하고, 부드럽게 동물의 눈꺼풀에 변환기 팁에 문의하십시오. </li><li> 외부 - 트리거 모드로 PAOM 레이저를 설정, 검류계 검사를 시작하고 동물 망막의 PAOM 단면 이미지를 실시간으로 디스플레이를 활성화합니다. PAOM 이미지 동안, 최고의 신호 대 잡음 비율 (SNR)를 보유하고 때까지 조심스럽게 변환기의 방향을 조정 골고루 지구 보여줍니다모두 스캔 방향으로 PA의 진폭 패턴을 ributed. </li><li> 검색 매개 변수를 설정하고 SD 10 월과 PAOM의 동시 망막 이미징을 실시합니다. SD 10 월과 PAOM 오프 라인의 3 차원 이미지를 재구성. 우리 재건 코드는 MATLAB에 기록 된 및 3 차원 시각화는 (Volview, Kitware) 프리웨어를 uing 달성했다. SD 10 월 재건을위한 알고리즘은 11. 심판에서 발견 할 수 있으며, PAOM 재건을위한 알고리즘은 참조에서 찾을 수 있습니다. 6 참조가. 13. 필요한 경우) 3.7 절차) -3.9를 반복합니다. </li><li> 실험 후, SD 10 월 프로빙 빛을 해제 즉시 홀더에서 동물을 제거하고 자연스럽게 깨어날 때까지 따뜻하게. 복구 할 눈에 대한 추가 시간 동안 어두운 환경에서 동물을 유지. 동물 마취 및 이미징 획득을 포함하여 전체 실험 기간은, 경험 교환을위한 미만 30 분입니다. </li></ol>

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모든 실험 동물의 절차는 노스 웨스턴 대학의 기관 동물 케어 및 사용위원회에 의해 승인되었습니다.

여기, 우리는 SD 10 월과 함께 PAOM를 사용하여 쥐의 눈의 망막 생체 이미징에 동시에 대한 자세한 지침을 제시한다. 광 산란 기반의 SD 10 월은 아마도 망막 영상 3에 대한 임상 &quot;금 표준&quot;입니다, 그러나,이 망막에서 광 흡수를 감지 할 문자를 구분하지 않습니다. 새로 개발 PAOM이 망막 6 광 흡수 특성을 제공하는 유일한 광 - 흡수 기반 안과 이미징 양상이다. 헤모글로빈과...

integrated photoacoustic ophthalmoscopy and spectral-domain optical coherence tomography

임상 진단 및 주요 안구 질환의 근본적인 조사 모두 크게 다양한 비 침습적 안과 이미징 기술의 혜택을 누리 실 수 있습니다. 망막 영상 등 fundus 사진 1, 공 촛점 스캐닝 레이저 ophthalmoscopy (cSLO) 2, 광학 일관성의 단층 촬영 (OCT) 3와 같은 modalities, 질병 onsets 및 progressions를 모니터링하고, 새로운 치료 전략을 개발에 큰 기여를합니다. 기존 그러나, 그들은 주로 망막에서 백 반영 광자에 의존하고 있습니다. 결과적으로, 보통 강한 망막 pathophysiology 상태와 관련된 망막의 광 흡수 특성은 기존의 이미징 기술에 의해 액세스 할 수 없습니다. Photoacoustic ophthalmoscopy (PAOM)는 높은 감도 4-7로 눈 광학 흡수 대조의 감지를 허용 신흥 망막 이미징 양상이다. PAOM 앤에osecond 레이저 펄스는 학생을 통해 전달하고 눈꺼풀에 부착 산만 초음파 변환기에 의해 감지 photoacoustic (PA) 신호를 유도 할 수있는 뒤쪽 눈에서 스캔합니다. 때문에 헤모글로빈과 멜라닌의 강한 광 흡수, PAOM은 비 invasively 이미징 망막과 choroidal vasculatures을, 고 대비 6,7에서 망막 색소 상피 (RPE) 멜라닌 할 수 있습니다. 더 중요한 것은, 잘 발달 spectroscopic photoacoustic 이미징 5,8에 따라, PAOM는 당뇨병 성 망막증과 같은 몇 가지 실명을 야기하는 안구 질환을 치료 9 생리와 병리를 공부에 중요 할 수 있습니다 망막 혈관에서 헤모글로빈 산소 포화도를 매핑 할 수있는 잠재력을 보유하고 neovascular 연령 관련 황반 변성. 또한, 유일한 기존의 광 - 흡수 기반 안과 이미징 양상되고, PAOM가 잘 구축 된 임상 안과 영상 테와 통합 할 수 있습니다chniques는 여러 광학 대비 6,10에 따라 눈의보다 포괄적 인 해부학 및 기능 평가를 얻을 수 있습니다. 이 작품에서 우리는 광학 흡수와 망막의 분산 특성이 모두 공개 아르 쥐의 생체 망막 영상에서 동시에에 PAOM 및 스펙트럼 도메인 10월 (SD 10 월)를 통합 할 수 있습니다. 시스템 구성, 시스템 정렬 및 이미징 인수는 표시됩니다.

그림 2는 SD 10 월과 PAOM는 흰둥이 쥐 (A와 B) 각각 색소 쥐 (C와 D)에 동시에 획득의 2-D fundus 이미지를 보여줍니다. SD 10 월 fundus 이미지 (그림 2A와 2C)에서, 망막 혈관은 빛을 프로빙의 헤모글로빈 흡수로 인해 어두운 모습을 갖추고 있습니다. 망막 혈관 (그림 2B의 RV)뿐만 아니라, PAOM 때문에 부족한 RPE의 멜라닌의 흰둥이 눈 choroidal vasculatu...

Watch this Scientific Journal Video about Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography at JoVE.com

Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography

Photoacoustic 안과 (PAOM), 광 - 흡수 기반 이미징 양상은 현재 안과 이미징 기술로 망막의 보완 평가를 제공합니다. 우리는 쥐의 동시 multimodal 망막 이미징을위한 스펙트럼 영역 광 간섭 단층 촬영의 (SD -10 월)와 통합 PAOM의 사용을보고합니다.

통합 Photoacoustic Ophthalmoscopy 및 스펙트럼 도메인 광 결맞음 단층 촬영 장치

Both the clinical diagnosis and fundamental investigation of major ocular diseases greatly benefit from various non-invasive ophthalmic imaging ...

integrated-photoacoustic-ophthalmoscopy-spectral-domain-optical

Research

JoVE Journal

Bioengineering

11.4K 조회수.  Northwestern University. Photoacoustic 안과 (PAOM), 광 - 흡수 기반 이미징 양상은 현재 안과 이미징 기술로 망막의 보완 평가를 제공합니다. 우리는 쥐의 동시 multimodal 망막 이미징을위한 스펙트럼 영역 광 간섭 단층 촬영의 (SD -10 월)와 통합 PAOM의 사용을보고합니다.

비디오: Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography

Three-dimensional Optical-resolution Photoacoustic Microscopy

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As the mainstays of in vivo three-dimensional (3-D) optical microscopy, single-/multi-photon fluorescence microscopy and optical coherence tomography (OCT) have demonstrated their extraordinary sensitivities to fluorescence and optical scattering contrasts, respectively. However, the optical absorption contrast of biological tissues, which encodes essential physiological/pathological information, has not yet been assessable. 
The emergence of biomedical photoacoustics has led to a new branch of optical microscopy optical-resolution photoacoustic microscopy (OR-PAM)1, where the optical irradiation is focused to the diffraction limit to achieve cellular1 or even subcellular2 level lateral resolution. As a valuable complement to existing optical microscopy technologies, OR-PAM brings in at least two novelties. First and most importantly, OR-PAM detects optical absorption contrasts with extraordinary sensitivity (i.e., 100%). Combining OR-PAM with fluorescence microscopy3 or with optical-scattering-based OCT4 (or with both) provides comprehensive optical properties of biological tissues. Second, OR-PAM encodes optical absorption into acoustic waves, in contrast to the pure optical processes in fluorescence microscopy and OCT, and provides background-free detection. The acoustic detection in OR-PAM mitigates the impacts of optical scattering on signal degradation and naturally eliminates possible interferences (i.e., crosstalks) between excitation and detection, which is a common problem in fluorescence microscopy due to the overlap between the excitation and fluorescence spectra. 
Unique for optical absorption imaging, OR-PAM has demonstrated broad biomedical applications since its invention, including, but not limited to, neurology5, 6, ophthalmology7, 8, vascular biology9, and dermatology10. In this video, we teach the system configuration and alignment of OR-PAM as well as the experimental procedures for in vivo functional microvascular imaging.

Optical-resolution photoacoustic microscopy (OR-PAM) is an emerging technology capable of imaging optical absorption contrasts in vivo with cellular resolution and sensitivity. Here, we provide a visualized instruction on the experimental protocols of OR-PAM, including system configuration, system alignment, typical in vivo experimental procedures, and functional imaging schemes.

입체 광학 해상도 Photoacoustic 현미경

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As ...

연구

생체공학

Detection and Isolation of Circulating Melanoma Cells using Photoacoustic Flowmetry

Circulating tumor cells (CTCs) are those cells that have separated from a macroscopic tumor and spread through the blood and lymph systems to seed secondary tumors1,2,3. CTCs are indicators of metastatic disease and their detection in blood samples may be used to diagnose cancer and monitor a patient&prime;s response to therapy. Since CTCs are rare, comprising about one tumor cell among billions of normal blood cells in advanced cancer patients, their detection and enumeration is a difficult task. We exploit the presence of pigment in most melanoma cells to generate photoacoustic, or laser induced ultrasonic waves in a custom flow cytometer for detection of circulating melanoma cells (CMCs)4,5. This process entails separating a whole blood sample using centrifugation and obtaining the white blood cell layer. If present in whole blood, CMCs will separate with the white blood cells due to similar density. These cells are resuspended in phosphate buffered saline (PBS) and introduced into the flowmeter. Rather than a continuous flow of the blood cell suspension, we induced two phase flow in order to capture these cells for further study. In two phase flow, two immiscible liquids in a microfluidic system meet at a junction and form alternating slugs of liquid6,7. PBS suspended white blood cells and air form microliter slugs that are sequentially irradiated with laser light. The addition of a surfactant to the liquid phase allows uniform slug formation and the user can create different sized slugs by altering the flow rates of the two phases. Slugs of air and slugs of PBS with white blood cells contain no light absorbers and hence, do not produce photoacoustic waves. However, slugs of white blood cells that contain even single CMCs absorb laser light and produce high frequency acoustic waves. These slugs that generate photoacoustic waves are sequestered and collected for cytochemical staining for verification of CMCs.

We have developed a flow cytometer using laser induced ultrasound to detect circulating melanoma cells as an early indicator of metastatic disease.

Photoacoustic Flowmetry를 사용하여 순환 흑색증 전지의 탐지 및 격리

Circulating tumor cells (CTCs) are those cells that have separated from a macroscopic tumor and spread through the blood and lymph systems to seed ...

In vitro Synthesis of Native, Fibrous Long Spacing and Segmental Long Spacing Collagen

Collagen fibrils are present in the extracellular matrix of animal tissue to provide structural scaffolding and mechanical strength. These native collagen fibrils have a characteristic banding periodicity of ~67 nm and are formed in vivo through the hierarchical assembly of Type I collagen monomers, which are 300 nm in length and 1.4 nm in diameter. In vitro, by varying the conditions to which the monomer building blocks are exposed, unique structures ranging in length scales up to 50 microns can be constructed, including not only native type fibrils, but also fibrous long spacing and segmental long spacing collagen. Herein, we present procedures for forming the three different collagen structures from a common commercially available collagen monomer. Using the protocols that we and others have published in the past to make these three types typically lead to mixtures of structures. In particular, unbanded fibrils were commonly found when making native collagen, and native fibrils were often present when making fibrous long spacing collagen. These new procedures have the advantage of producing the desired collagen fibril type almost exclusively. The formation of the desired structures is verified by imaging using an atomic force microscope.

In vitro Synthesis of Native, Fibrous Long Spacing and Segmental Long Spacing Collagen

Simple and reproducible procedures are described for making three structurally distinct collagen assemblies from a common commercially available Type I collagen monomer. Native type, fibrous long spacing or segmental long spacing collagen can be constructed by varying the conditions to which the 300 nm long and 1.4 nm diameter monomer building block is exposed.

기본, 섬유 긴 간격 및 Segmental 긴 간격 콜라겐의 체외 합성에

Collagen fibrils are present in the  extracellular matrix of animal tissue to provide structural scaffolding and  mechanical strength. These native ...

Photoacoustic Cystography

Conventional pediatric cystography, which is based on diagnostic X-ray using a radio-opaque dye, suffers from the use of harmful ionizing radiation. The risk of bladder cancers in children due to radiation exposure is more significant than many other cancers. Here we demonstrate the feasibility of nonionizing and noninvasive photoacoustic (PA) imaging of urinary bladders, referred to as photoacoustic cystography (PAC), using near-infrared (NIR) optical absorbents (i.e. methylene blue, plasmonic gold nanostructures, or single walled carbon nanotubes) as an optical-turbid tracer. We have successfully imaged a rat bladder filled with the optical absorbing agents using a dark-field confocal PAC system. After transurethral injection of the contrast agents, the rat's bladders were photoacoustically visualized by achieving significant PA signal enhancement. The accumulation was validated by spectroscopic PA imaging. Further, by using only a laser pulse energy of less than 1 mJ/cm2 (1/20 of the safety limit), our current imaging system could map the methylene-blue-filled-rat-bladder at the depth of beyond 1 cm in biological tissues in vivo. Both in vivo and ex vivo PA imaging results validate that the contrast agents were naturally excreted via urination. Thus, there is no concern regarding long-term toxic agent accumulation, which will facilitate clinical translation.

Photoacoustic cystography (PAC) has a great potential to map urinary bladders, a radiation sensitive internal organ in pediatric patients, without using any ionizing radiation or toxic contrast agent. Here we demonstrate the use of PAC for mapping urinary bladders with an injection of optical-opaque tracers in rats in vivo.

광 음향 Cystography

Conventional pediatric cystography, which is based on diagnostic X-ray using a radio-opaque dye, suffers from the use of harmful ionizing radiation. The ...

Preparation and Photoacoustic Analysis of Cellular Vehicles Containing Gold Nanorods

Gold nanorods are attractive for a range of biomedical applications, such as the photothermal ablation and the photoacoustic imaging of cancer, thanks to their intense optical absorbance in the near-infrared window, low cytotoxicity and potential to home into tumors. However, their delivery to tumors still remains an issue. An innovative approach consists of the exploitation of the tropism of tumor-associated macrophages that may be loaded with gold nanorods in vitro. Here, we describe the preparation and the photoacoustic inspection of cellular vehicles containing gold nanorods. PEGylated gold nanorods are modified with quaternary ammonium compounds, in order to achieve a cationic profile. On contact with murine macrophages in ordinary Petri dishes, these particles are found to undergo massive uptake into endocytic vesicles. Then these cells are embedded in biopolymeric hydrogels, which are used to verify that the stability of photoacoustic conversion of the particles is retained in their inclusion into cellular vehicles. We are confident that these results may provide new inspiration for the development of novel strategies to deliver plasmonic particles to tumors.

We show the preparation and address the feasibility of cellular vehicles containing gold nanorods for the photoacoustic imaging of cancer.

금 나노 막대를 포함하는 세포 차량의 제조 및 광 음향 분석

Gold nanorods are attractive for a range of biomedical applications, such as the photothermal ablation and the photoacoustic imaging of cancer, thanks to ...

Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that implantation of a bone autograft would induce greater bone regeneration by abundant blood vessel formation. To investigate the effect of the graft on neovascularization at the defect site, we developed a micro&#8211;computed tomography (&#181;CT) approach to characterize newly forming blood vessels, which involves systemic perfusion of the animal with a polymerizing contrast agent. This method enables detailed vascular analysis of an organ in its entirety. Additionally, blood perfusion was assessed using fluorescence imaging (FLI) of a blood-borne fluorescent agent. Bone formation was quantified by FLI using a hydroxyapatite-targeted probe and &#181;CT analysis. Stem cell recruitment was monitored by bioluminescence imaging (BLI) of transgenic mice that express luciferase under the control of the osteocalcin promoter. Here we describe and demonstrate preparation of the allograft, calvarial defect surgery, &#181;CT scanning protocols for the neovascularization study and bone formation analysis (including the in vivo perfusion of contrast agent), and the protocol for data analysis.
The 3D high-resolution analysis of vasculature demonstrated significantly greater angiogenesis in animals with implanted autografts, especially with respect to arteriole formation. Accordingly, blood perfusion was significantly higher in the autograft group by the 7th day after surgery. We observed superior bone mineralization and measured greater bone formation in animals that received autografts. Autograft implantation induced resident stem cell recruitment to the graft-host bone suture, where the cells differentiated into bone-forming cells between the 7th and 10th postoperative day. This finding means that enhanced bone formation may be attributed to the augmented vascular feeding that characterizes autograft implantation. The methods depicted may serve as an optimal tool to study bone regeneration in terms of tightly bounded bone formation and neovascularization.

Implantation of autologous and allogeneic bone grafts constitute accepted approaches to treat major craniofacial bone loss. Yet the effect of graft composition on the interplay among neovascularization, cell differentiation and bone formation is unclear. We present a multimodal imaging protocol aimed to elucidate the angiogenesis-osteogenesis interdependence at the graft proximity.

컴퓨터 단층 촬영 및 골 형성 - 혈관 신생 커플 링의 광학 이미징 두개골 뼈자가 이식과 동종 이식 통합을 평가하기 위해

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that ...

Switchable Acoustic and Optical Resolution Photoacoustic Microscopy for In Vivo Small-animal Blood Vasculature Imaging

Photoacoustic microscopy (PAM) is a fast-growing invivo imaging modality that combines both optics and ultrasound, providing penetration beyond the optical mean free path (~1 mm in skin) with high resolution. By combining optical absorption contrast with the high spatial resolution of ultrasound in a single modality, this technique can penetrate deep tissues. Photoacoustic microscopy systems can have either a low acoustic resolution and probe deeply or a high optical resolution and probe shallowly. It is challenging to achieve high spatial resolution and large depth penetration with a single system. This work presents an AR-OR-PAM system capable of both high-resolution imaging at shallow depths and low-resolution deep-tissue imaging of the same sample in vivo. A lateral resolution of 4 &#181;m with 1.4 mm imaging depth using optical focusing and a lateral resolution of 45 &#181;m with 7.8 mm imaging depth using acoustic focusing were successfully demonstrated using the combined system. Here,&#160;in vivo&#160;small-animal blood vasculature imaging is performed to demonstrate its biological imaging capability.

Switchable Acoustic and Optical Resolution Photoacoustic Microscopy for In Vivo Small-animal Blood Vasculature Imaging

Here a switchable acoustic resolution (AR) and optical resolution (OR) photoacoustic microscopy (AR-OR-PAM) system capable of both high resolution imaging at shallow depth and low resolution deep tissue imaging on the same sample in vivo is demonstrated.

전환 가능한 음향 및 광학 해상도 Photoacoustic Microscopy for<em&gt; In Vivo</em&gt; 소 동물 혈관 조영술

Photoacoustic microscopy (PAM) is a fast-growing invivo imaging modality that combines both optics and ultrasound, providing penetration beyond the ...

A High-performance Compact Photoacoustic Tomography System for In Vivo Small-animal Brain Imaging

In vivo small-animal imaging has an important role to play in preclinical studies. Photoacoustic tomography (PAT) is an emerging hybrid imaging modality that shows great potential for both preclinical and clinical applications. Conventional optical parametric oscillator-based PAT (OPO-PAT) systems are bulky and expensive and cannot provide high-speed imaging. Recently, pulsed-laser diodes (PLDs) have been successfully demonstrated as an alternative excitation source for PAT. Pulsed-laser diode PAT (PLD-PAT) has been successfully demonstrated for high-speed imaging on photoacoustic phantoms and biological tissues. This work provides a visualized experimental protocol for in vivo brain imaging using PLD-PAT. The protocol includes the compact PLD-PAT system configuration and its description, animal preparation for brain imaging, and a typical experimental procedure for 2D cross-sectional rat brain imaging. The PLD-PAT system is compact and cost-effective and can provide high-speed, high-quality imaging. Brain images collected in vivo at various scan speeds are presented.

A High-performance Compact Photoacoustic Tomography System for In Vivo Small-animal Brain Imaging

A compact pulsed-laser diode-based photoacoustic tomography (PLD-PAT) system for high-speed in vivo brain imaging in small animals is demonstrated.

다음을위한 고성능 컴팩트 광 음향 단층 촬영 시스템<em&gt; In Vivo</em&gt; 소형 동물 뇌 영상

In vivo small-animal imaging has an important role to play in preclinical studies. Photoacoustic tomography (PAT) is an emerging hybrid imaging modality ...

Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy (oSLO) and Optical Coherence Tomography (OCT)

While fluorescence imaging is widely used in ophthalmology, a large field of view (FOV) three-dimensional (3D) fluorescence retinal image is still a big challenge with the state-of-the-art retinal imaging modalities because they would require z-stacking to compile a volumetric dataset. Newer optical coherence tomography (OCT) and OCT angiography (OCTA) systems overcome these restrictions to provide three-dimensional (3D) anatomical and vascular images, but the dye-free nature of OCT cannot visualize leakage indicative of vascular dysfunction. This protocol describes a novel oblique scanning laser ophthalmoscopy (oSLO) technique that provides 3D volumetric fluorescence retinal imaging. The setup of the imaging system generates the oblique scanning by a dove tail slider and aligns the final imaging system at an angle to detect fluorescent cross-sectional images. The system uses the laser scanning method, and therefore, allows an easy incorporation of OCT as a complementary volumetric structural imaging modality. In vivo imaging on rat retina is demonstrated here. Fluorescein solution is intravenously injected to produce volumetric fluorescein angiography (vFA).

Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy oSLO and Optical Coherence Tomography OCT

Here, we present a protocol to get a large field of view (FOV) three-dimensional (3D) fluorescence and OCT retinal image by using a novel imaging multimodal platform. We will introduce the system setup, the method of alignment, and the operational protocols. In vivo imaging will be demonstrated, and representative results will be provided.

복합 체적 망막 이미징 오블리크 스캐닝 레이저 Ophthalmoscopy (오슬로) 및 광학 일관성 단층 촬영 (OCT)

While fluorescence imaging is widely used in ophthalmology, a large field of view (FOV) three-dimensional (3D) fluorescence retinal image is still a big ...

Nondestructive Monitoring of Degradable Scaffold-Based Tissue-Engineered Blood Vessel Development Using Optical Coherence Tomography

Engineered vascular grafts with structural and mechanical properties similar to natural blood vessels are expected to meet the growing demand for arterial bypass. Characterization of the growth dynamics and remodeling process of degradable polymer scaffold-based tissue-engineered blood vessels (TEBVs) with pulsatile stimulation is crucial for vascular tissue engineering. Optical imaging techniques stand out as powerful tools for monitoring vascularization of engineered tissue enabling high-resolution imaging in real-time culture. This paper demonstrates a nondestructive and fast real-time imaging strategy to monitor the growth and remodeling of TEBVs in long-term culture by using optical coherence tomography (OCT). Geometric morphology is evaluated, including vascular remodeling process, wall thickness, and comparison of TEBV thickness in different culture time points and presence of pulsatile stimulation. Finally, OCT provides practical possibilities for real-time observation of the degradation of polymer in the reconstructing tissues under pulsatile stimulation or not and in each vessel segment, by compared with the assessment of polymer degradation using scanning electron microscopic(SEM) and polarized microscope.

A step by step protocol for nondestructive and long-period monitoring the process of vascular remodeling and scaffold degradation in real-time culture of biodegradable polymeric scaffold-based tissue-engineered blood vessels with pulsatile stimulation using optical coherence tomography is described here.

광학 일관성 단층 촬영을 사용 하 여 분해 비 계 기반 조직 설계 혈관 개발의 비파괴 모니터링

Engineered vascular grafts with structural and mechanical properties similar to natural blood vessels are expected to meet the growing demand for arterial ...