DR은 독일 연구 재단 (DFG) 연구비 (RA 1분의 1,848)과 유럽 연구위원회 그랜트부터의 지원을 인정합니다. VN은 유럽 연구위원회 고급 탐정 상 재정 지원을 인정하고, 의학 상에 BMBF의 혁신.

π-FBG 감지기 1. Optoacoustic 특성 <ol><li> 한천에 현탁 미세한 구형의 준비 : <ol><li> 유리 비커에 증류수로 한천 분말 (1.3 중량 %)을 혼합. 끓는 온도에 가까운 용액을 가열하고 용액이 공기 거품의 명확하고 무료로 될 때까지 한천 분말을 용해 할 수있는 핫 플레이트 자석 교반기 장치를 사용합니다. 대안 적으로, 한천 용액을 수동으로 유리 교반기를 사용하여 교반하면서 수행 종래의 전자 렌지를 사용하여 가열 될 수있다. 플라스틱 금형, 그 팁 예를 들어 주사기에 뜨거운 용액을 붓고 잘라. </li><li> 한천 솔루션에 대한 현미경 분야의 소량을 뿌려 솔루션이 완전히 응고 될 때까지 기다립니다. 플런저를 밀어 금형 밖으로 고체 한천 팬텀을 가져 가라. </li><li> 입체 현미경으로 팬텀을보기는 하나의 미세한 영역을 포함 한천의 작은 조각을 잘라. </li><li> 1.1.1 단계를 반복 t을 추가한천 솔루션 단일 미세한 구를 포함하는 고체 한천 조각 오. </li><li> 응고 후, 미세 구가 가까운 팬텀의 표면에 위치하도록 현미경 한천 팬텀를 잘라. </li></ol></li><li> Optoacoustic 측정 <ol><li> π-FBG의 양쪽에 단단히 섬유를 보유하는 두 개의 V 홈 섬유 홀더를 사용하여 세 가지 차원 (XYZ) 번역 시스템 운영 단계에 홀더를 연결. 섬유는 초음파의 전달을 가능하게 침수되어 있는지 확인합니다. </li><li> 고전력 나노초 펄스 레이저 광 섬유의 다른 부분을 조명 의해 감지 π-FBG 요소의 대략적인 위치를 찾는다. 조명이 π-FBG에서 수행되는 경우에는 약한 코팅의 광 흡수는 신호를 생성합니다. </li><li> 직접 π-FBG 아래 한천 포함 된 미세 구를 놓습니다. 미세한 영역은 육안으로 볼 수 있어야합니다. </li><li> 이동 스테이지를 사용하여, 미세한 구형에서 신호가 최강과 그 대응 시간 지연이 최소 인 위치를 찾기 위해 접지에 평행 한 평면에서 π-FBG의 2D 검사를 수행한다. </li><li> 미세한 영역에 최대 전력을 제공하는 조명에 마지막 조정을 수행합니다. </li><li> 이동 스테이지를 사용하여 π-FBG의 3 차원 스캔을 수행하고, 각 위치에 대하여 신호를 기록한다. </li><li> 초음파 검출기의 공간적 종속 주파수 응답을 얻기 위해 푸리에 기록 시간 영역의 초음파 신호의 변환을 수행한다. </li></ol></li></ol> 견고 함과 π-FBG 감지기의 성능의 감도 2. 추정 <ol><li> π-FBG의 양쪽에 단단히 섬유를 보유하고 π-FBG 잠수함 두 개의 V 홈 섬유 홀더를 사용합니다. </li><li> π-FBG 얼굴을 튼튼하게 어두운 판 또는 흑연 막대를 삽입하고 그것을 재치를 조명강한 음향 장을 생성하는 H 고전력 나노초 펄스 레이저 빔. </li><li> 물 탱크 내부에 물 펌프를 배치하고 환경 조건의 급격한 변화를 만들기 위해 전원을 켭니다. </li><li> 시스템의 견고성을 추정하기 위해, 잠금 회로와 출력을 측정 모두 온 오프. 제공된 잠금이 수행되지 않은 경우, 정확하게 초음파 신호를 검출하는 것은 불가능하다. </li><li> 물 펌프의 전원을 끕니다. </li><li> 인해 소스의 높은 간섭으로 감도 이득을 추정하기 위해, 저 간섭 소스와 광대역 펄스 레이저를 교체하고 음향 측정을 반복한다. 저 간섭 소스가 사용될 때 감도의 강도의 순서 이상의 감소가 예상된다. </li></ol>

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저자는 더 경쟁 재정적 이익이 없다는 것을 선언합니다.

결론적으로, 초음파 감지를위한 새로운 광 방법은 π-FBG 펄스 간섭의 조합을 기반으로하는, 도입된다. 이 기술은 특히 거의 임의의 개체 조명 패턴을 가능 센싱 요소의 투명성 때문에 optoacoustic 이미징 애플리케이션에 적합하다. 반면, 표준 압전 기반의 초음파 탐지기는 불투명하기 때문에 부피가 큰 영상 설정에지도 이미지가 개체에 광학 경로의 일부를 차단합니다. 개발 된 광 검출기 따라서 optoa...

초음파 감지기는 다양한 이미징 애플리케이션에 중요한 역할을한다. 통상적으로, 초음파는 전압 신호 (1)에 압력 파동을 변형 압전 트랜스 듀서에 의해 검출된다. optoacoustic 이미징, 초음파는 고출력 변조 된 광 2-6 개체를 조명하여 열 팽창의 과정을 통해 생성된다. 압전 트랜스 듀서 optoacoustic 응용 프로그램의 선택의 방법이지만 소형 압전 트랜스 듀서는 종종 낮은 감도를 특징으로하고 있기 때문에, 이들의 사용은 종종 주로 소형화를 방해한다. 압전 트랜스 듀서는 광학적으로 불투명하기 때문에 또한, 그들은 심각하게 사용할 수있는 영상 구성에 대한 가능성을 제한, 이미지가 개체에 빛 전달을 방해 할 수 있습니다. 트랜스 듀서에 대한 개체에서 후방 산란되는 광은 또한 초음파의 적절한 검출을 제한하고 광학적으로 인해 유도 parasit으로 이미징 시스템의 설계를 복잡하게 할 수IC는 트랜스 듀서 (7)에 신호를 보낸다. 초음파의 광 검출기는 optoacoustic 영상 시나리오 8-12에서 많은 혜택을 제공합니다 압전 트랜스 듀서에 대한 가능한 대안으로 인식되고있다 : 그들은 종종 투명하며 일반적으로 감도의 손실없이 소형화 할 수있다. 광 검출기의 작동 원리로 인해 초음파의 존재로 광학 매질에서 생성 분 변형 간섭계의 검출이다. 종종, 광 공진기는 광 신호의 위상에 대한 변형의 효과를 증가 따라서, 연장 기간에 대한 섭동 매체에 광을 포착함으로써 검출 감도를 향상시키기 위해 사용된다. 이러한 경우, 광 검출 방식은 직접 공진기에 변형을 구조화 관해서 공진 파장 모니터링 변형에 기초한다. 가장 일반적으로, 좁은 선폭의 연속파 (CW) 기술은 CW 레이저를 일까지 조정 된 사용E 공진 파장. 공진에서 작은 변화는 따라서 용이하게 모니터링 할 수있는 투과 / 반사 된 레이저 빛의 강도 변화를 일으키는 공진 내의 레이저의 파장의 상대 위치를 변경 파장. 공진 시프트가 너무 강한 경우에는, 예를 들면 공진 효과적으로 검출기 (13)를 포화시키는, 레이저의 파장에서 떨어져 완전히 이동할 수 있고, 압력, 온도 나 진동에 큰 변화 때문에. 펄스 간섭 (14)는 신호 포화의 한계에 대한 해결책을 제공하며, 휘발성 환경 조건에서 초음파 감지 할 수 있습니다. 반면 CW 방식을 선폭에게 좁은 펄스 간섭은 공진기를 조명하기 위해 광대역 펄스 소스를 사용한다. 공진이 이동하면서이 경우, 상기 공진기는, 그 공진 주파수에 대응하는 파장들만을 송신하는 대역 통과 필터로서 작용다시 14,15 직교하도록 고정 마하 젠더 간섭계를 이용하여, 예 공진기의 출력시 광 신호의 파장 변화를 측정함으로써 검출. 자동 리셋 회로는 즉시 인해 환경 조건에 극단적 인 변화에 분실되는 경우 간섭계의 작동 지점을 복원하는 데 사용됩니다. 이 때문에 소스의 상대적으로 넓은 대역폭, 공진 파장은 열악한 환경 조건에서 안정된 검출 작업을 가능하게, 심지어 강한 섭동에서 조명 대역 내에서 유지됩니다. 심문, 즉 광학 펄스를위한 코 히어 런트 소스의 사용은 낮은 노이즈 검출을 용이하게한다. 실험에 사용 된 대응 펄스 간섭계 시스템은도 1에 도시된다. 심문 사용할 펄스 레이저가 100 이상 60 mW의 그리고 스펙트럼 폭의 출력 전력과 100 MHz의 반복율에서 90 FSEC 펄스를 생성뉴 멕시코. 광학 필터는 약 0.4 ㎚의 FWHM 스펙트럼 폭이 있고 공진 주파수에 동조 하였다. 필터 후, 광 증폭기는 필터링에 상당한 손실을 보상하기 위해 사용되었다. 추가 필터링은 증폭기에서 증폭 된 자연 방출을 줄이기 위해 증폭단 후에 도포 하였다. 실험에 사용되는 공진기, 특히 초음파 감지 의료용 Teraxion 사 제조 PI-위상 시프트 된 광섬유 브래그 격자 (π-FBG) 08이고, π-FBG를 모든 섬유 성분있는 장점을 가지고 따라서 강력한 소규모.도 2는이 연구에서 사용 된 광섬유의 치수와 15 MHz의 소형화 혈관 내 초음파 (IVUS) 압전 변환기 사이의 비교를 나타낸다. 이러한 평면 도파로 제작 마이크로 링 공진기와 같은 일부 다른 공진 기반의 탐지 방식은 구성 요소의에서 커플 링 섬유를 필요로입력 및 출력, 더 깨지기 쉬운 장치에 선행 또는 소형화를 방해 하나. 대조적으로,-π에서 광섬유 브래그 격자는 파이버 성분이고, 추가로 섬유 결합을 필요로하지 않는다. π-광섬유 브래그 격자의 공진은 그들의 중앙 PI 위상 시프트에 의해 생성된다; 광은 격자 자체의 길이보다 상당히 짧은 섬유의 부분 위에 PI 위상 시프트 주위 포획된다. 우리의 실험에서는, π-FBG는 4mm 및 κ = 2mm의 결합 계수의 길이를 가지고 있었다 -1 감도는 감성 지수 κ의 비율로 격자의 중심에서 감소함에 따라, 그 길이를 따라 불균일하게 분포시켰다 . 감도 분포 (SD)의 전체 폭의 절반 - 최대 (FWHM)은 약 350 μM이었다. 격자의 공명 폭은 그 길이 및 다음 식에 따라 그 결합 계수 모두에 의해 결정된다 : <img alt="식 (1)" fo:content-width="1.5in" src= &quot;/ files/ftp_upload/50847/50847eq1.jpg&quot;폭 = &quot;150&quot;/&gt; (1) λ는 공진 파장, n은 어디 EFF는 섬유 (8)으로 안내 모드의 유효 굴절률이다. π-FBG 감지기 이미징 응용 프로그램에 적합 여부를 평가하려면, 공간적으로 의존 응답은 넓은 주파수 대역에 걸쳐 측정 할 필요가있다. 그러나이 작업은 기존의 음향 기술을 사용할 때 매우 도전이다. 따라서 우리는 투명한 한천에 포함 된 어두운 미세한 구체 optoacoustic 점 광원 역할을하는 초음파 검출기 특성 16 optoacoustic 방법을 사용합니다. 우리의 실험에서, 미세 구가 약 100 ㎛의 직경을 가지고 있으며, 10 Hz에서의 반복률, 약 13 나노초의 펄스 지속 시간, 그리고 200 mW의 평균 전력으로 고성능 나노초 펄스 광으로 조명된다. 미세한 SPH에 입금 광 에너지ERES optoacoustic 효과로 인해 광대역 초음파 신호를 생성한다. π-FBG 감지기는 그것의 공간적 따라 음향 응답을 얻기 위해 미세한 영역에 상대적으로 번역됩니다. 그림 3은 optoacoustic 실험의 그림을 보여줍니다. 일반적으로,이 기술은 초음파 검출기의 종류를 특성화하기 위해 사용될 수있다.

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			<td height="43" style="height:43px;width:216px;">&#960;-FBG</td>
			<td style="width:71px;">Teraxion Inc.</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">&#160;Custom made device</td>
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			<td height="43" style="height:43px;width:216px;">microscopic sphere</td>
			<td style="width:71px;">Cospheric LLC</td>
			<td style="width:119px;">BKPMS 90-106um- 10g</td>
			<td style="width:167px;">100 &#181;m polyethylene microsphere</td>
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			<td height="64" style="height:64px;width:216px;">Femto-second pulse laser used for interrogation&#160;</td>
			<td style="width:71px;">Menlo Systems GmbH</td>
			<td style="width:119px;">T-Light Femtosecond Laser</td>
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			<td height="64" style="height:64px;width:216px;">Optical filter</td>
			<td style="width:71px;">Optoplex Corporation</td>
			<td style="width:119px;">2-Port Optical Tunable Filter (50 GHz)</td>
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			<td height="64" style="height:64px;width:216px;">Optical amplifier</td>
			<td style="width:71px;">Amonics</td>
			<td style="width:119px;">AEDFA-PM-PA-35-B-FC</td>
			<td style="width:167px;">Benchtop 35dB Gain Pre Amp Polarization Maintaining EDFA&#160;</td>
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			<td height="232" style="height:232px;width:216px;">50/50 coupler</td>
			<td style="width:71px;">OZ-Optics</td>
			<td style="width:119px;">FUSED-22-1550-8/125-50/50-3S3S3S3S-3-0.5-PM</td>
			<td style="width:167px;">Fused 2x2 fiber splitter with 0.5 meter long, 3mm OD PVC jacketed 1550nm 8/125&#956; PM fiber 
			pigtails, 50/50 split ratio in the slow axes of PM fibers and with super FC/PC connectors on all 
			ports.</td>
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			<td height="43" style="height:43px;width:216px;">Fiber holder</td>
			<td style="width:71px;">Thorlabs</td>
			<td style="width:119px;">T711/M-250</td>
			<td style="width:167px;">Metric, Post-Mountable Fiber Clamp, 250 &#181;m&#160;</td>
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			<td height="43" style="height:43px;width:216px;">Agar for microbiology</td>
			<td style="width:71px;">Sigma Aldrich</td>
			<td style="width:119px;">05039-500G</td>
			<td style="width:167px;"></td>
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			<td height="64" style="height:64px;width:216px;">Nano-second pulse laser used for generating the optoacoustic signals</td>
			<td style="width:71px;">Opotek</td>
			<td style="width:119px;">VIBRANT Arrow 532 type I</td>
			<td style="width:167px;"></td>
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			<td height="43" style="height:43px;width:216px;">Graphite rod</td>
			<td style="width:71px;">&#160;Faber-Castell</td>
			<td style="width:119px;">120700</td>
			<td style="width:167px;">Faber-Castell Pencil Leads - 0.7 mm</td>
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wideband optical detector of ultrasound for medical imaging applications

최근 optoacoustic 이미징 분야에서 입증 된 바와 같이 초음파의 광 센서는 압전 기술에 대한 유망한 대안이다. 의료 분야에서는, 광 센싱 기술의 주요 제한 사항 중 하나는 검출 포화있다 환경 조건, 압력 및 온도 등의 변화로 그 감수성이다. 또한, 임상 적 환경은 종종 센서의 크기와 견고성에 대한 엄격한 제한을 부과한다. 본 연구에서는 펄스 간섭 및 섬​​유 기반의 광 센서의 조합은 초음파 감지 보여줍니다. 모든 섬유 기술의 사용과 같은 혈관 이미징 매우 까다로운 의료 애플리케이션과 호환 기계적가요 감지 소자로 연결하는 반면 펄스 간섭계는, 환경 조건의 급속한 변화의 존재 판독 시스템의 강력한 성능을 가능하게한다. 짧은 센서 길이를 달성하기 위해서PI-위상 시프트 광섬유 브래그 격자는 350 μM의 유효 길이에 걸쳐 빛을 트래핑 공진기 역할을하는 데 사용됩니다. 높은 대역폭을 사용하려면, 센서 등의 혈관 이미징 원주 영상의 형상에 매우 유용합니다 초음파의 측방 감지에 사용됩니다. optoacoustic 촬상 설정은 상이한 위치에서 탄성 포인트 소스에 대한 센서의 응답을 결정하는 데 사용된다.

도 4a 및도 4b는 각각 π-FBG의 중심으로부터 옵셋 세 섬유가 1 ㎜의 거리에있는 미세한 구형에서 신호 및 해당 스펙트럼을 보여준다. 도 3에 도시 된 바와 같은 오프셋은, Z 방향으로 주어진다. 분명히, 고주파 초음파 (f&gt; 10 MHz 이상)에 대한 광 검출기의 감도는 이방성이고, π-FBG의 중심에 직접 미세 구 이상일 때 가장 높은 . 실리카 섬유와 물 사이의 높은 음향 임피던스 불?...

Watch this Scientific Journal Video about Wideband Optical Detector of Ultrasound for Medical Imaging Applications at JoVE.com

Wideband Optical Detector of Ultrasound for Medical Imaging Applications

종종 안정적인 환경 조건을 필요로하기 때문에 초음파의 광학 검출 많은 영상 시나리오에서 비실용적이다. 우리는 제한적인 시나리오, 예를 들면 혈관 내 응용 프로그램에서 optoacoustic 영상에 적합한 소형화 및 민감도 수준의 휘발성 환경에서 초음파 감지하는 광학 기술을 보여줍니다.

광대역 의료 이미징 애플리케이션을위한 초음파의 광 검출기

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic ...

wideband-optical-detector-ultrasound-for-medical-imaging

Research

JoVE Journal

Bioengineering

10.7K 조회수.  Technical University of Munich and Helmholtz Center Munich.  종종 안정적인 환경 조건을 필요로하기 때문에 초음파의 광학 검출 많은 영상 시나리오에서 비실용적이다. 우리는 제한적인 시나리오, 예를 들면 혈관 내 응용 프로그램에서 optoacoustic 영상에 적합한 소형화 및 민감도 수준의 휘발성 환경에서 초음파 감지하는 광학 기술을 보여줍니다. 

비디오: Wideband Optical Detector of Ultrasound for Medical Imaging Applications

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 ...

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Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting airways, whereas adenocarcinomas are typically more peripheral in location. Lung malignancy detection early in the disease process may be difficult due to several limitations: radiological resolution, bronchoscopic limitations in evaluating tissue underlying the airway mucosa and identifying early pathologic changes, and small sample size and/or incomplete sampling in histology biopsies. High resolution imaging modalities, such as optical frequency domain imaging (OFDI), provide non-destructive, large area 3-dimensional views of tissue microstructure to depths approaching 2 mm in real time (Figure 1)2-6. OFDI has been utilized in a variety of applications, including evaluation of coronary artery atherosclerosis6,7 and esophageal intestinal metaplasia and dysplasia6,8-10.
Bronchoscopic OCT/OFDI has been demonstrated as a safe in vivo imaging tool for evaluating the pulmonary airways11-23 (Animation). OCT has been assessed in pulmonary airways16,23 and parenchyma17,22 of animal models and in vivo human airway14,15. OCT imaging of normal airway has demonstrated visualization of airway layering and alveolar attachments, and evaluation of dysplastic lesions has been found useful in distinguishing grades of dysplasia in the bronchial mucosa11,12,20,21. OFDI imaging of bronchial mucosa has been demonstrated in a short bronchial segment (0.8 cm)18. Additionally, volumetric OFDI spanning multiple airway generations in swine and human pulmonary airways in vivo has been described19. Endobronchial OCT/OFDI is typically performed using thin, flexible catheters, which are compatible with standard bronchoscopic access ports. Additionally, OCT and OFDI needle-based probes have recently been developed, which may be used to image regions of the lung beyond the airway wall or pleural surface17.
While OCT/OFDI has been utilized and demonstrated as feasible for in vivo pulmonary imaging, no studies with precisely matched one-to-one OFDI:histology have been performed. Therefore, specific imaging criteria for various pulmonary pathologies have yet to be developed. Histopathological counterparts obtained in vivo consist of only small biopsy fragments, which are difficult to correlate with large OFDI datasets. Additionally, they do not provide the comprehensive histology needed for registration with large volume OFDI. As a result, specific imaging features of pulmonary pathology cannot be developed in the in vivo setting. Precisely matched, one-to-one OFDI and histology correlation is vital to accurately evaluate features seen in OFDI against histology as a gold standard in order to derive specific image interpretation criteria for pulmonary neoplasms and other pulmonary pathologies. Once specific imaging criteria have been developed and validated ex vivo with matched one-to-one histology, the criteria may then be applied to in vivo imaging studies. Here, we present a method for precise, one to one correlation between high resolution optical imaging and histology in ex vivo lung resection specimens. Throughout this manuscript, we describe the techniques used to match OFDI images to histology. However, this method is not specific to OFDI and can be used to obtain histology-registered images for any optical imaging technique. We performed airway centered OFDI with a specialized custom built bronchoscopic 2.4 French (0.8 mm diameter) catheter. Tissue samples were marked with tissue dye, visible in both OFDI and histology. Careful orientation procedures were used to precisely correlate imaging and histological sampling locations. The techniques outlined in this manuscript were used to conduct the first demonstration of volumetric OFDI with precise correlation to tissue-based diagnosis for evaluating pulmonary pathology24. This straightforward, effective technique may be extended to other tissue types to provide precise imaging to histology correlation needed to determine fine imaging features of both normal and diseased tissues.

Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

A method to image ex vivo pulmonary resection specimens with optical frequency domain imaging (OFDI) and obtain precise correlation to histology is described, which is essential to developing specific OFDI interpretation criteria for pulmonary pathology. This method is applicable to other tissue types and imaging techniques to obtain precise imaging to histology correlation for accurate image interpretation and assessment. Imaging criteria established with this technique would then be applicable to image assessment in future in vivo studies.

의 광 주파수 도메인 영상<em&gt; 예 생체</em&gt; 폐 절제술의 표본 : 조직 병리학 간 상관 관계에 하나에 하나의 이미지를 얻기

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting ...

Preparation of Mica Supported Lipid Bilayers for High Resolution Optical Microscopy Imaging

Supported lipid bilayers (SLBs) are widely used as a model for studying membrane properties (phase separation, clustering, dynamics) and its interaction with other compounds, such as drugs or peptides. However SLB characteristics differ depending on the support used. 
Commonly used techniques for SLB imaging and measurements are single molecule fluorescence microscopy, FCS and atomic force microscopy (AFM). Because most optical imaging studies are carried out on a glass support, while AFM requires an extremely flat surface (generally mica), results from these techniques cannot be compared directly, since the charge and smoothness properties of these materials strongly influence diffusion. Unfortunately, the high level of manual dexterity required for the cutting and gluing thin slices of mica to the glass slide presents a hurdle to routine use of mica for SLB preparation. Although this would be the method of choice, such prepared mica surfaces often end up being uneven (wavy) and difficult to image, especially with small working distance, high numerical aperture lenses. Here we present a simple and reproducible method for preparing thin, flat mica surfaces for lipid vesicle deposition and SLB preparation. Additionally, our custom made chamber requires only very small volumes of vesicles for SLB formation. The overall procedure results in the efficient, simple and inexpensive production of high quality lipid bilayer surfaces that are directly comparable to those used in AFM studies.

We present a method of preparing mica supported lipid bilayers for high resolution microscopy. Mica is transparent and flat on an atomic scale, but rarely used in imaging because of handling difficulties; our preparation results in even deposition of the mica sheet, and reduces the material used in bilayer preparation.

운모의 준비 고해상도 광학 현미경 이미징 지질 이중층 지원

Supported lipid bilayers (SLBs) are widely used as a model for studying membrane properties (phase separation, clustering, dynamics) and its interaction ...

Biofunctionalized Prussian Blue Nanoparticles for Multimodal Molecular Imaging Applications

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, complementary imaging techniques. These imaging agents facilitate the real-time assessment of pathways and mechanisms in vivo, which enhance both diagnostic and therapeutic efficacy. This article presents the protocol for the synthesis of biofunctionalized Prussian blue nanoparticles (PB NPs) - a novel class of agents for use in multimodal, molecular imaging applications. The imaging modalities incorporated in the nanoparticles, fluorescence imaging and magnetic resonance imaging (MRI), have complementary features. The PB NPs possess a core-shell design where gadolinium and manganese ions incorporated within the interstitial spaces of the PB lattice generate MRI contrast, both in T1 and T2-weighted sequences. The PB NPs are coated with fluorescent avidin using electrostatic self-assembly, which enables fluorescence imaging. The avidin-coated nanoparticles are modified with biotinylated ligands that confer molecular targeting capabilities to the nanoparticles. The stability and toxicity of the nanoparticles are measured, as well as their MRI relaxivities. The multimodal, molecular imaging capabilities of these biofunctionalized PB NPs are then demonstrated by using them for fluorescence imaging and molecular MRI in vitro.

This protocol describes the synthesis of biofunctionalized Prussian blue nanoparticles and their use as multimodal, molecular imaging agents. The nanoparticles have a core-shell design where gadolinium or manganese ions within the nanoparticle core generate MRI contrast. The biofunctional shell contains fluorophores for fluorescence imaging and targeting ligands for molecular targeting.

멀티 모달 분자 이미징 애플리케이션을위한 Biofunctionalized 프 러시안 블루 나노 입자

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, ...

Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An oscillatory motion is generated at the focus of a 93-element and 4.5 MHz center frequency HIFU transducer by applying a 25 Hz amplitude-modulated signal using a function generator. A 64-element and 2.5 MHz imaging transducer with 68kPa peak pressure is confocally placed at the center of the HIFU transducer to acquire the radio-frequency (RF) channel data. In this protocol, real-time monitoring of thermal ablation using HIFU with an acoustic power of 7 W on canine livers in vitro is described. HIFU treatment is applied on the tissue during 2 min and the ablated region is imaged in real-time using diverging or plane wave imaging up to 1,000 frames/second. The matrix of RF channel data is multiplied by a sparse matrix for image reconstruction. The reconstructed field of view is of 90&#176; for diverging wave and 20 mm for plane wave imaging and the data are sampled at 80 MHz. The reconstruction is performed on a Graphical Processing Unit (GPU) in order to image in real-time at a 4.5 display frame rate. 1-D normalized cross-correlation of the reconstructed RF data is used to estimate axial displacements in the focal region. The magnitude of the peak-to-peak displacement at the focal depth decreases during the thermal ablation which denotes stiffening of the tissue due to the formation of a lesion. The displacement signal-to-noise ratio (SNRd) at the focal area for plane wave was 1.4 times higher than for diverging wave showing that plane wave imaging appears to produce better displacement maps quality for HMIFU than diverging wave imaging.

Real-time Monitoring of High Intensity Focused Ultrasound HIFU Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound HMIFU

This article describes real-time monitoring of HIFU ablation in canine liver with high frame rate ultrasound imaging using diverging and plane wave imaging. Harmonic Motion Imaging for Focused Ultrasound is used to image the decrease of acoustic radiation force induced displacement in the ablated region.

높은 강도의 실시간 모니터링의 초음파 (HIFU) 절제를 집중<em&gt; 체외</em&gt; 집중 초음파에 대한 조화 운동 이미징을 사용하여 개 간을 (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An ...

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 ...

High-throughput Identification of Bacteria Repellent Polymers for Medical Devices

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as contributing to antimicrobial resistance. One possible avenue for the reduction of device-associated infections is the identification of bacteria-repellent polymer coatings for these devices, which would prevent bacterial binding at the initial attachment step. A method for the identification of such repellent polymers, based on the parallel screening of hundreds of polymers using a microarray, is described here. This high-throughput method resulted in the identification of a range of promising polymers that resisted binding of various clinically relevant bacterial species individually and also as multi-species communities. One polymer, PA13 (poly(methylmethacrylate-co-dimethylacrylamide)), demonstrated significant reduction in attachment of a number of hospital isolates when coated onto two commercially available central venous catheters. The method described could be applied to identify polymers for a wide range of applications in which modification of bacterial attachment is important.

A high-throughput microarray method for the identification of polymers which reduce bacterial surface binding on medical devices is described.

의료 기기에 대한 박테리아의 높은 처리량 식별 구충제 폴리머

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as ...

Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal Therapy and Surgery) project. One of the aims of this project is to engineer novel, real-time image processing methods for intra-operative use in the treatment of congenital birth defects, such as spina bifida and the twin-to-twin transfusion syndrome. The developed target allows for the sterility-preserving optical distortion calibration of endoscopes within a few minutes. Good optical distortion calibration and compensation are important for mitigating undesirable effects like radial distortions, which not only hamper accurate imaging using existing endoscopic technology during fetal surgery, but also make acquired images less suitable for potentially very useful image computing applications, like real-time mosaicing. In this paper proposes a novel fabrication method to create an affordable, sterilizable calibration target suitable for use in a clinical setup. This method involves etching a calibration pattern by laser cutting a sandblasted stainless steel sheet. This target was validated using the camera calibration module provided by OpenCV, a state-of-the-art software library popular in the computer vision community.

This article describes the design and development of a sterilizable custom camera optical distortion calibration target for the peri-operative, fluid-immersed calibration of endoscopes during endoscopic interventions.

유체 - 침지 Fetoscope 광학 왜곡 보정 의료 수준의 소독 가능 대상

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal ...

Long-term Live Imaging Device for Improved Experimental Manipulation of Zebrafish Larvae

The zebrafish larva is an important model organism for both developmental biology and wound healing. Further, the zebrafish larva is a valuable system for live high-resolution microscopic imaging of dynamic biological phenomena in space and time with cellular resolution. However, the traditional method of agarose encapsulation for live imaging can impede larval development and tissue regrowth. Therefore, this manuscript describes the zWEDGI (zebrafish Wounding and Entrapment Device for Growth and Imaging), which was designed and fabricated as a functionally compartmentalized device to orient larvae for high-resolution microscopy while permitting caudal fin transection within the device and subsequent unrestrained tail development and re-growth. This device allows for wounding and long-term imaging while maintaining viability. Given that the zWEDGI mold is 3D printed, the customizability of its geometries make it easily modified for diverse zebrafish imaging applications. Furthermore, the zWEDGI offers numerous benefits, such as access to the larva during experimentation for wounding or for the application of reagents, paralleled orientation of multiple larvae for streamlined imaging, and reusability of the device.

This manuscript describes the zWEDGI (zebrafish Wounding and Entrapment Device for Growth and Imaging), which is a compartmentalized device designed to orient and restrain zebrafish larvae. The design permits tail transection and long-term collection of high-resolution fluorescent microscopy images of wound healing and regeneration.

Zebrafish 애벌레의 향상 된 실험적인 조작에 대 한 장기 라이브 이미징 장치

The zebrafish larva is an important model organism for both developmental biology and wound healing. Further, the zebrafish larva is a valuable system for ...

Optical Imaging of Isolated Murine Ventricular Myocytes

The ability to isolate adult cardiac myocytes has permitted researchers to study a variety of cardiac pathologies at the single cell level. While advances in calcium sensitive dyes have permitted the robust optical recording of single cell calcium dynamics, recording of robust transmembrane optical voltage signals has remained difficult. Arguably, this is because of the low single to noise ratio, phototoxicity, and photobleaching of traditional potentiometric dyes. Therefore, single cell voltage measurements have long been confined to the patch clamp technique which while the gold standard, is technically demanding and low throughput. However, with the development of novel potentiometric dyes, large, fast optical responses to changes in voltage can be obtained with little to no phototoxicity and photobleaching. This protocol describes in detail how to isolate adult murine myocytes which can be used for cellular shortening, calcium, and optical voltage measurements. Specifically, the protocol describes how to use a ratiometric calcium dye, a single-excitation calcium dye, and a single excitation voltage dye. This approach can be used to assess the cardiotoxicity and arrhythmogenicity of various chemical agents. While phototoxicity is still an issue at the single cell level, methodology is discussed on how to reduce it.

We present the methodology for the isolation of murine myocytes and how to obtain voltage or calcium traces simultaneously with sarcomere shortening traces using fluorescence photometry with simultaneous digital cell geometry measurements.

고립 된 뮤린 심실 근세포의 광학 이미징

The ability to isolate adult cardiac myocytes has permitted researchers to study a variety of cardiac pathologies at the single cell level. While advances ...