투석 직원과 지치 의과 대학 사이타마 의료 센터의 신장학과 구성원에게 감사드립니다. 영어 편집을 해주신 Editage (www.editage.com)님께 감사드립니다.

모든 참가자는 서면 동의서를 제공했습니다. 이 연구는 일본 지치 의과 대학 사이타마 의료 센터의 기관 검토위원회 (RIN 15-104)의 승인을 받았습니다.
1.rSO2의 모니터링 장치
<ol><li>조직 산소화 측정을 위한 NIRS 장치를 준비합니다. 이 장치에는 4개의 채널이 있으며 동시에 최대 4개의 기관에서 측정을 수행할 수 있습니다.</li>
	<li>NIRS 모니터링을 위한 측정 센서를 준비하여 두 개의 부착 파장에서 근적외선을 전송하여 각 기관의 rSO2 값을 평가합니다.</li>
</ol>2. 측정 센서 부착
<ol><li>HD 전에 각 환자가 최소 5분 동안 앙와위 자세로 쉬도록 합니다.</li>
	<li>측정 센서를 이마, 오른쪽 hypochondrium 및 다리 아래쪽에 부착하여 각각 뇌, 간 및 다리 근육에서 rSO2 를 평가합니다.</li>
	<li>뇌 산소 공급 모니터링<ol><li>측정 센서를 지배적 인 반구의 이마에 부착하십시오.</li>
	</ol></li>
	<li>간 산소 공급 모니터링<ol><li>신체 표면에서 환자의 간까지의 깊이를 측정하기 위해 초음파 검사를 준비하십시오. 이 측정값이 신체 표면에서 20-30mm 이내에 있는지 확인합니다. 다음으로, 측정 센서를 오른쪽 hypochondrium에 부착하십시오. 알림: 이 장치에서 rSO2 값은 신체 표면에서 20-30mm 떨어진 깊은 조직에서 얻어야 합니다. 일부 예에서, 간은 두꺼운 피하 지방의 존재로 인해 신체 표면으로부터 30 mm 이상 위치할 수 있다.</li>
	</ol></li>
	<li>근육 산소 공급 모니터링<ol><li>측정 센서를 오른쪽 또는 양측 아래쪽 다리에 부착합니다.</li>
	</ol></li>
	<li>센서 연결 및 장치 전원 공급<ol><li>각 센서를 장치의 리드에 연결합니다. 그런 다음 장치를 켜고 산소 측정을 시작하십시오.</li>
	</ol></li>
</ol>3. 투석 션트 천공 및 모니터링 시작
<ol><li>투석 션트 천공<ol><li>환자의 투석 션트에 구멍을 뚫어 HD 치료를 시작합니다. 이때 투석기가 장착된 디지털 혈압계를 이용하여 혈압을 측정하고 주사기를 이용하여 혈액 샘플을 수집한다.</li>
	</ol></li>
	<li>모니터링 시작<ol><li>HD 치료를 시작한 후 뇌, 간 및 다리 근육의 세 기관의 조직 산소 공급 모니터링을 시작하십시오.</li>
	</ol></li>
	<li>HD 중 rSO2 모니터링<ol><li>각 장기의 rSO2 값의 변화를 관찰하고 심박수, 정맥압 및 혈액량을 포함하여 HD 치료 중에 수행되는 일반적인 모니터링 외에도 정기적으로 BP를 측정합니다. 부착 영역과 센서와 리드 사이의 연결을 확인하십시오.</li>
	</ol></li>
</ol>

<ol>
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이해 상충이 없습니다.

NIRS 모니터링은 주로 대뇌 rSO2를 평가하기 위해, 특히 체외 순환을 필요로 하는 심혈관 또는 뇌혈관 수술에서 사용되었다. HD 치료를 포함한 체외 순환 동안 일부 장기는 상대 허혈 7,17,18을 나타낼 수 있습니다. 그러나 조직 산소화가 낮아지는지 여부는 불분명합니다. HD 중 근육 경련이나 복통은 장기 저관류를 통한 투석 중 저혈압의 전구 증상 중 하나일 수 있습니다. 그러나 HD 치료에서 현재 조직 산소화를 실시간으로 평가하는 방법은 없습니다. 따라서 우리는 위에서 설명한 프로토콜을 사용하여 장기 산소 공급을 평가하기 위해이 모니터링 장치를 사용하는 데 중점을 두었습니다. 이 프로토콜은 HD 환자에게 비침습적이며 조직 산소화의 변화를 실시간으로 확인하는 데 유용합니다.
도 1에 나타낸 바와 같이, DM이 있는 HD 환자에서의 대뇌rSO2는 DM이 없는 환자에서의 것보다 낮았다. 또한, 더 높은 혈관 석회화는 더 낮은 뇌 산소화와 관련이 있었다19. 따라서, 미세 및 거대 혈관 장애는 뇌 산소 공급의 손상과 관련 될 수있다. 더욱이, 대뇌rSO2는HD 환자4에서 60-150 mmHg 내에서 비교적 일정하게 유지되었다. 그러나 투석 중 저혈압에서 혈압의 급격한 감소는 장기 산소 공급의 변화로 이어질 수 있습니다(그림 2). 이 프로토콜에 의한rSO2 값의 변화를 관찰하기 전에, 우리는 HD 동안 조직 산소화의 영향을 확인할 수 없었다. 지속적인 동맥압 모니터링 외에도 BP는 일반적으로 간헐적으로 평가됩니다. 대조적으로, NIRS에 의한 지속적인 모니터링은 HD 동안 혈압의 변화에 의해 감지되기 전에 장기 산소 공급의 변화를 감지할 수 있습니다. 따라서 우리는 BP의 저하를 확인하기 전에 저산소증 상태를 관찰 할 수있었습니다. 혈압의 변화 이외에, 수혈, 저밀도 지단백질 성분채집 및 한외여과는 하부 다리20,21,22의 rSO2와 같은 기관 산소화의 변화를 야기할 수 있다. 따라서 우리는 HD 동안 장기 산소 공급의 급격한 변화에 주의를 기울여야 합니다.
이 프로토콜에는 몇 가지 제한 사항이 있습니다. 첫째, 대뇌 rSO2는 이마에서만 측정할 수 있었다; 그러나 후방 뇌 순환에서이 평가를 수행하는 것은 어렵습니다. 측정 센서는 씰 유형이므로 센서를 머리카락에 고정할 수 있습니다. 다음으로, 간rSO2의 측정은 피하 지방 두께의 확인을 필요로 한다. 비만 환자에서, 측정된rSO2는 근적외선이 표적 기관에 도달할 수 없기 때문에 정확하지 않을 수 있다. 셋째,rSO2 값은 신체 움직임 또는 위치(즉, 앙와위 및 앉은 자세)에 의해 영향을 받을 수 있다. 따라서 HD 동안 환자는 가능한 한 침대에서 같은 위치에 있는 동안 측정해야 합니다.
더욱이, 이 프로토콜에서 측정된rSO2 값은 혼합 정맥 포화도를 나타내며, 이는 정맥(70-80%), 모세관(5%), 및 동맥(20-25%) 혈액에서 조직 산소화를 반영한다(23). 따라서,rSO2 값의 변화가 경피적 산소 포화도24,25에서의 변화를 반드시 평행하게 하는 것은 아니다. 따라서, 측정된rSO2 값은 신중하게 해석되어야 한다. 또한 이 프로토콜은 NIRS 모니터링 장치를 사용할 수 있는 경우 환자에게 수행하기 쉽고 비침습적입니다. 따라서 이 방법은 널리 일반적인 다양성을 제공합니다. 우리는 이 NIRS 모니터링이 미래에 투석 모니터로 투석 기계가 장착되기를 바랍니다.
결론적으로, 우리는 HD를 받는 환자에서 NIRS에 의한 조직 산소화 측정을 위한 프로토콜을 설명했습니다. HD 중 이러한 모니터링은 HD 요법의 영향을 받는 조직 산소화의 변화에 대한 새로운 발견을 제공할 수 있습니다.

근적외선 분광법 (NIRS)은 조직 산소화, 특히 다양한 임상 환경에서 뇌 산소화의 마커 인 국소 산소 포화도 (rSO 2)를 평가하는 데 사용되었습니다 1,2,3 최근에는 혈액 투석 (HD)4,5,6,7,8,9,10, 11. 대뇌 rSO2는 HD 환자 또는 투석되지 않은 만성 신장 질환(CKD) 환자의 인지 기능과 관련이 있는 것으로 보고되었습니다11,12. 그러나 지금까지 만성콩팥병 환자에서 NIRS 모니터링의 사용은 제한적이었습니다.
NIRS 모니터링은 실시간 및 비침습적이기 때문에 HD를 받는 환자에서 모니터링 장치로서의 유용성을 평가했습니다. NIRS는 주로 대뇌 rSO2를 측정하는 데 사용되지만, HD 동안 다른 장기의 rSO2 값도 조사했습니다. 구체적으로,rSO2 측정 센서를 이마, 오른쪽 hypochondrium 및 다리 아래쪽에 부착하여 각각 뇌, 간 및 하부 근육에서 rSO2를 평가하였다. 결과는 NIRS 모니터링이 헌팅턴병 중 장기 산소화 변화 또는 CKD 환자의 조직 산소화 영향을 미치는 요인을 명확히 하는 새로운 접근 방식이 될 수 있음을 보여주었습니다.
현재까지 임상 환경13,14,15에서 HD, 혈액량 모니터링, 중심 정맥 산소 포화도, 흉부 입원 및 전자 청진기 유도 예상 혈압(BP) 동안 지속적인 모니터링이 수행되었습니다. 그러나 저혈압의 예측이나 장치의 광범위한 사용에는 한계가 있습니다. 대조적으로, 여기서 새로운 비침습적 접근 방식은 개별 장기의 투석 내 산소 역학에 대한 실시간 정보를 제공할 수 있습니다. 따라서 이 모니터링 방법은 투석 중 저혈압의 초기 단계에서 일과성 장기 허혈을 감지할 수 있고 HD의 안전한 수행을 허용할 수도 있습니다. 이 기사는 HD를 받는 환자에게 적용되는 rSO2로 대표되는 조직 산소화를 측정하는 프로토콜을 설명합니다.

<table>
	<tbody>
		<tr>
			<td>DBB-100NX</td>
			<td>Nikkiso</td>
			<td>DBB-100NX</td>
			<td>Dialysis machine</td>
		</tr>
		<tr>
			<td>INVOS 5100c</td>
			<td>Covidien Japan</td>
			<td>INVOSTM 5100c</td>
			<td>tissue oxygenation device</td>
		</tr>
		<tr>
			<td>SOMASENSER</td>
			<td>Covidien Japan</td>
			<td>CV-SAFB-SM/INTL</td>
			<td>NIRS sensor</td>
		</tr>
	</tbody>
</table>

measurement of tissue oxygenation using near-infrared spectroscopy in patients undergoing hemodialysis

근적외선 분광법(NIRS)은 최근 심혈관 및 뇌 수술, 신생아 모니터링 및 병원 전 의학을 포함한 임상 환경에서 조직 산소화 마커인 국소 산소 포화도(rSO2)를 측정하는 도구로 적용되었습니다. NIRS 모니터링 장치는 실시간 및 비침습적이며 주로 수술 또는 집중 치료 중 중환자의 뇌 산소 공급을 평가하는 데 사용되었습니다. 지금까지 혈액 투석 (HD)을 포함한 만성 신장 질환 (CKD) 환자에서 NIRS 모니터링의 사용은 제한적이었습니다. 따라서, 우리는 HD 동안 일부 장기에서rSO2 값을 조사하였다. 2개의 부착 파장에서 근적외선을 전송하는 NIRS 장치를 사용하여rSO2 값을 모니터링했습니다. HD 환자는 뇌, 간 및 다리 아래 근육에서 rSO2를 각각 평가하기 위해 이마, 오른쪽 hypochondrium 및 다리 아래쪽에 부착된 rSO2 측정 센서를 사용하여 앙와위 자세로 배치되었습니다. NIRS 모니터링은 헌팅턴병 중 장기 산소화의 변화 또는 CKD 환자의 조직 산소화에 영향을 미치는 요인을 명확히 하는 새로운 접근 방식이 될 수 있습니다. 이 기사는 HD 환자에서 적용되는rSO2로 대표되는 조직 산소화를 측정하는 프로토콜을 설명합니다.

HD 이전의 대뇌 rSO2 값은 건강한 피험자보다 낮았고 당뇨병(DM)이 있는 HD 환자의 대뇌rSO2 값은 DM이 없는 HD 환자의 값보다 낮았습니다(그림 1)16. 또한 HD 동안 BP의 감소 없이 조직 산소 공급이 계속되지만 투석 중 저혈압으로 인한 뇌 및 간 rSO2의 변화를 우연히 관찰했습니다(그림 2). 지속적인 모니터링으로 인해, 조직 산소화의 변화는 간헐적으로 모니터링된 BP에 의해서보다 더 빨리 관찰되었다. 데이터는 표준 오차± 평균으로서 표현되었다. 쌍을 이루지 않은 값에 대한 분산 분석을 사용하여 세 그룹을 비교했습니다.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61721/61721fig01.jpg"> 그림 1: 당뇨병이 있는 HD 환자(n=27), 당뇨병이 없는 HD 환자(n=27) 및 건강한 피험자(n=28)의 HD 전 대뇌 rSO2 비교. 환자는 평균 연령이 67.7 세에서 1.2 세이고 HD 기간이 6.5 세에서 1.9 세± 38 명의 남성과 16 명의 여성± 포함되었습니다. 만성 신장 질환의 원인은 DM (27 명), 만성 사구체 신염 (14 명), 신장 경화증 (4 명), 다낭성 신장 질환 (4 명) 및 기타 (5 명)였다. 오차 막대는 표준 오차를 나타냅니다. 데이터는 이전 보고서16을 기반으로 했으며 그림은 수정되었습니다. 데시미터; 당뇨병, HD; 혈액 투석, rSO2; 국소 산소 포화도. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61721/61721fig01large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/61721/61721fig2v2.jpg"> 그림 2 : 급성 투석 내 저혈압 환자에서 뇌 및 간 rSO2 의 변화. 혈압; 혈압, HR; 시간,rSO2; 국소 산소 포화도, UFR; 한외 여과율. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61721/61721fig2v2large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a>

Watch this Scientific Journal Video about Measurement of Tissue Oxygenation Using Near-Infrared Spectroscopy in Patients Undergoing Hemodialysis at JoVE.com

Measurement of Tissue Oxygenation Using Near-Infrared Spectroscopy in Patients Undergoing Hemodialysis

우리는 근적외선 분광 모니터를 사용하여 혈액 투석 (HD) 환자의 국소 산소 포화도 (rSO2)를 측정하는 프로토콜을 제시합니다. rSO2 값은 조직 산소화의 지표이다. 이 비침습적 및 실시간 모니터링은 HD 동안 장기 산소 공급의 변화를 확인하는 데 유용할 수 있습니다.

혈액 투석을받는 환자에서 근적외선 분광법을 사용한 조직 산소화 측정

Near-infrared spectroscopy (NIRS) has recently been applied as a tool to measure regional oxygen saturation (rSO2), a marker of tissue oxygenation, in ...

measurement-tissue-oxygenation-using-near-infrared-spectroscopy

Nanyang Technological University

Research

JoVE Journal

Medicine

2.1K 조회수.  Jichi Medical University. 우리는 근적외선 분광 모니터를 사용하여 혈액 투석 (HD) 환자의 국소 산소 포화도 (rSO2)를 측정하는 프로토콜을 제시합니다. rSO2 값은 조직 산소화의 지표이다. 이 비침습적 및 실시간 모니터링은 HD 동안 장기 산소 공급의 변화를 확인하는 데 유용할 수 있습니다.

비디오: Measurement of Tissue Oxygenation Using Near-Infrared Spectroscopy in Patients Undergoing Hemodialysis

Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health disorders such as chronic wounds. We report the development of a dual-mode imaging system for non-invasive and non-contact imaging of cutaneous tissue oxygenation and vascular function. The imaging system integrated an infrared camera, a CCD camera, a liquid crystal tunable filter and a high intensity fiber light source. A Labview interface was programmed for equipment control, synchronization, image acquisition, processing, and visualization. Multispectral images captured by the CCD camera were used to reconstruct the tissue oxygenation map. Dynamic thermographic images captured by the infrared camera were used to reconstruct the vascular function map. Cutaneous tissue oxygenation and vascular function images were co-registered through fiduciary markers. The performance characteristics of the dual-mode image system were tested in humans.

A dual-mode imaging system was developed for non-contact assessment of cutaneous tissue oxygenation and vascular function.

피부 조직 산소와 혈관 기능의 듀얼 모드 영상

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health ...

연구

의학

In vivo Near Infrared Fluorescence (NIRF) Intravascular Molecular Imaging of Inflammatory Plaque, a Multimodal Approach to Imaging of Atherosclerosis

The vascular response to injury is a well-orchestrated inflammatory response triggered by the accumulation of macrophages within the vessel wall leading to an accumulation of lipid-laden intra-luminal plaque, smooth muscle cell proliferation and progressive narrowing of the vessel lumen. The formation of such vulnerable plaques prone to rupture underlies the majority of cases of acute myocardial infarction. The complex molecular and cellular inflammatory cascade is orchestrated by the recruitment of T lymphocytes and macrophages and their paracrine effects on endothelial and smooth muscle cells.1
Molecular imaging in atherosclerosis has evolved into an important clinical and research tool that allows in vivo visualization of inflammation and other biological processes. Several recent examples demonstrate the ability to detect high-risk plaques in patients, and assess the effects of pharmacotherapeutics in atherosclerosis.4 While a number of molecular imaging approaches (in particular MRI and PET) can image biological aspects of large vessels such as the carotid arteries, scant options exist for imaging of coronary arteries.2 The advent of high-resolution optical imaging strategies, in particular near-infrared fluorescence (NIRF), coupled with activatable fluorescent probes, have enhanced sensitivity and led to the development of new intravascular strategies to improve biological imaging of human coronary atherosclerosis.
Near infrared fluorescence (NIRF) molecular imaging utilizes excitation light with a defined band width (650-900 nm) as a source of photons that, when delivered to an optical contrast agent or fluorescent probe, emits fluorescence in the NIR window that can be detected using an appropriate emission filter and a high sensitivity charge-coupled camera. As opposed to visible light, NIR light penetrates deeply into tissue, is markedly less attenuated by endogenous photon absorbers such as hemoglobin, lipid and water, and enables high target-to-background ratios due to reduced autofluorescence in the NIR window. Imaging within the NIR 'window' can substantially improve the potential for in vivo imaging.2,5
Inflammatory cysteine proteases have been well studied using activatable NIRF probes10, and play important roles in atherogenesis. Via degradation of the extracellular matrix, cysteine proteases contribute importantly to the progression and complications of atherosclerosis8. In particular, the cysteine protease, cathepsin B, is highly expressed and colocalizes with macrophages in experimental murine, rabbit, and human atheromata.3,6,7 In addition, cathepsin B activity in plaques can be sensed in vivo utilizing a previously described 1-D intravascular near-infrared fluorescence technology6, in conjunction with an injectable nanosensor agent that consists of a poly-lysine polymer backbone derivatized with multiple NIR fluorochromes (VM110/Prosense750, ex/em 750/780nm, VisEn Medical, Woburn, MA) that results in strong intramolecular quenching at baseline.10 Following targeted enzymatic cleavage by cysteine proteases such as cathepsin B (known to colocalize with plaque macrophages), the fluorochromes separate, resulting in substantial amplification of the NIRF signal. Intravascular detection of NIR fluorescence signal by the utilized novel 2D intravascular NIRF catheter now enables high-resolution, geometrically accurate in vivo detection of cathepsin B activity in inflamed plaque.
In vivo molecular imaging of atherosclerosis using catheter-based 2D NIRF imaging, as opposed to a prior 1-D spectroscopic approach,6 is a novel and promising tool that utilizes augmented protease activity in macrophage-rich plaque to detect vascular inflammation.11,12 The following research protocol describes the use of an intravascular 2-dimensional NIRF catheter to image and characterize plaque structure utilizing key aspects of plaque biology. It is a translatable platform that when integrated with existing clinical imaging technologies including angiography and intravascular ultrasound (IVUS), offers a unique and novel integrated multimodal molecular imaging technique that distinguishes inflammatory atheromata, and allows detection of intravascular NIRF signals in human-sized coronary arteries.

In vivo Near Infrared Fluorescence NIRF Intravascular Molecular Imaging of Inflammatory Plaque, a Multimodal Approach to Imaging of Atherosclerosis

We detail a new near-infrared fluorescence (NIRF) catheter for 2-dimensional intravascular molecular imaging of plaque biology in vivo. The NIRF catheter can visualize key biological processes such as inflammation by reporting on the presence of plaque-avid activatable and targeted NIR fluorochromes. The catheter utilizes clinical engineering and power requirements and is targeted for application in human coronary arteries. The following research study describes a multimodal imaging strategy that utilizes a novel in vivo intravascular NIRF catheter to image and quantify inflammatory plaque in proteolytically active inflamed rabbit atheromata.

염증성 플라크의 적외선 형광 (NIRF) Intravascular 분자 이미징, Multimodal 접근 가까운 생체내에서 죽상 경화증의 영상을

The vascular response to injury is a well-orchestrated inflammatory response triggered by the accumulation of macrophages within the vessel wall leading ...

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department

Carbon dioxide (CO2) along with oxygen (O2) share the role of being the most important gases in the human body. The measuring of expired CO2 at the mouth has solicited growing clinical interest among physicians in the emergency department for various indications: (1) surveillance et monitoring of the intubated patient; (2) verification of the correct positioning of an endotracheal tube; (3) monitoring of a patient in cardiac arrest; (4) achieving normocapnia in intubated head trauma patients; (5) monitoring ventilation during procedural sedation. The video allows physicians to familiarize themselves with the use of capnography and the text offers a review of the theory and principals involved. In particular, the importance of CO2 for the organism, the relevance of measuring expired CO2, the differences between arterial and expired CO2, the material used in capnography with their artifacts and traps, will be reviewed. Since the main reluctance in the use of expired CO2 measurement is due to lack of correct knowledge concerning the physiopathology of CO2 by the physician, we hope that this explanation and the video sequences accompanying will help resolve this limitation.

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department

This video describes how to perform CO2 measurement in intubated as well as spontaneously breathing patients. The main clinical indications refer to emergency situations: (1) verifying adequate positioning of an endotracheal tube; (2) achieving normocapnia in trauma patients; (3) monitoring ventilation in the case of procedural sedation.

만료 CO 2</sub응급실에서 Intubated 또는 자연스럽게 호흡 환자> 측정

Carbon dioxide (CO2) along with oxygen (O2) share the role of being the most important gases in the human body. The measuring of expired CO2 at the mouth ...

Near Infrared Optical Projection Tomography for Assessments of &beta;-cell Mass Distribution in Diabetes Research

By adapting OPT to include the capability of imaging in the near infrared (NIR) spectrum, we here illustrate the possibility to image larger bodies of pancreatic tissue, such as the rat pancreas, and to increase the number of channels (cell types) that may be studied in a single specimen. We further describe the implementation of a number of computational tools that provide: 1/ accurate positioning of a specimen's (in our case the pancreas) centre of mass (COM) at the axis of rotation (AR)2; 2/ improved algorithms for post-alignment tuning which prevents geometric distortions during the tomographic reconstruction2 and 3/ a protocol for intensity equalization to increase signal to noise ratios in OPT-based BCM determinations3. In addition, we describe a sample holder that minimizes the risk for unintentional movements of the specimen during image acquisition. Together, these protocols enable assessments of BCM distribution and other features, to be performed throughout the volume of intact pancreata or other organs (e.g. in studies of islet transplantation), with a resolution down to the level of individual islets of Langerhans.

Near Infrared Optical Projection Tomography for Assessments of &#946;-cell Mass Distribution in Diabetes Research

We describe the adaptation of optical projection tomography (OPT)1 to imaging in the near infrared spectrum, and the implementation of a number of computational tools. These protocols enable assessments of pancreatic &beta;-cell mass (BCM) in larger specimens, increase the multichannel capacity of the technique and increase the quality of OPT data.

당뇨병 연구에서 β-세포 질량 분포의 평가를위한 적외선 광학 프로젝션 단층 촬영 부근

By adapting OPT to include the capability of imaging in the near infrared (NIR) spectrum, we here illustrate the possibility to image larger bodies of ...

Tissue-simulating Phantoms for Assessing Potential Near-infrared Fluorescence Imaging Applications in Breast Cancer Surgery

Inaccuracies in intraoperative tumor localization and evaluation of surgical margin status result in suboptimal outcome of breast-conserving surgery (BCS). Optical imaging, in particular near-infrared fluorescence (NIRF) imaging, might reduce the frequency of positive surgical margins following BCS by providing the surgeon with a tool for pre- and intraoperative tumor localization in real-time. In the current study, the potential of NIRF-guided BCS is evaluated using tissue-simulating breast phantoms for reasons of standardization and training purposes.
Breast phantoms with optical characteristics comparable to those of normal breast tissue were used to simulate breast conserving surgery. Tumor-simulating inclusions containing the fluorescent dye indocyanine green (ICG) were incorporated in the phantoms at predefined locations and imaged for pre- and intraoperative tumor localization, real-time NIRF-guided tumor resection, NIRF-guided evaluation on the extent of surgery, and postoperative assessment of surgical margins. A customized NIRF camera was used as a clinical prototype for imaging purposes.
Breast phantoms containing tumor-simulating inclusions offer a simple, inexpensive, and versatile tool to simulate and evaluate intraoperative tumor imaging. The gelatinous phantoms have elastic properties similar to human tissue and can be cut using conventional surgical instruments. Moreover, the phantoms contain hemoglobin and intralipid for mimicking absorption and scattering of photons, respectively, creating uniform optical properties similar to human breast tissue. The main drawback of NIRF imaging is the limited penetration depth of photons when propagating through tissue, which hinders (noninvasive) imaging of deep-seated tumors with epi-illumination strategies.

Near-infrared fluorescence (NIRF) imaging may improve therapeutic outcome of breast cancer surgery by enabling intraoperative tumor localization and evaluation of surgical margin status. Using tissue-simulating breast phantoms containing fluorescent tumor-simulating inclusions, potential clinical applications of NIRF imaging in breast cancer patients can be assessed for standardization and training purposes.

유방암 수술의 잠재적 인 근적외선 형광 이미징 응용 프로그램을 평가하는 팬텀을 조직 시뮬레이션

Inaccuracies in intraoperative tumor localization and evaluation of surgical margin status result in suboptimal outcome of breast-conserving surgery ...

Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker&#160;&#8212; a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

This protocol describes the application of combined near-infrared fluorescent (NIRF) imaging and micro-computed tomography (microCT) for visualizing cerebral thromboemboli. This technique allows the quantification of thrombus burden and evolution. The NIRF imaging technique visualizes fluorescently labeled thrombus in excised brain, while the microCT technique visualizes thrombus inside living animals using gold-nanoparticles.

직접 대뇌 Thromboemboli 시각화를위한 결합 된 근적외선 형광 이미징 및 마이크로 계산 된 단층 촬영

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of ...

Bioluminescence and Near-infrared Imaging of Optic Neuritis and Brain Inflammation in the EAE Model of Multiple Sclerosis in Mice

Experimental autoimmune encephalomyelitis (EAE) in SJL/J mice is a model for relapsing-remitting multiple sclerosis (RRMS). Clinical EAE scores describing motor function deficits are basic readouts of the immune-mediated inflammation of the spinal cord. However, scores and body weight do not allow for an in vivo assessment of brain inflammation and optic neuritis. The latter is an early and frequent manifestation in about 2/3 of MS patients. Here, we show methods for bioluminescence and near-infrared live imaging to assess EAE evoked optic neuritis, brain inflammation, and blood-brain barrier (BBB) disruption in living mice using an in vivo imaging system. A bioluminescent substrate activated by oxidases primarily showed optic neuritis. The signal was specific and allowed the visualization of medication effects and disease time courses, which paralleled the clinical scores. Pegylated fluorescent nanoparticles that remained within the vasculature for extended periods of time were used to assess the BBB integrity. Near-infrared imaging revealed a BBB leak at the peak of the disease. The signal was the strongest around the eyes. A near-infrared substrate for matrix metalloproteinases was used to assess EAE-evoked inflammation. Auto-fluorescence interfered with the signal, requiring spectral unmixing for quantification. Overall, bioluminescence imaging was a reliable method to assess EAE-associated optic neuritis and medication effects and was superior to the near-infrared techniques in terms of signal specificity, robustness, ease of quantification, and cost.

We show a technique for in vivo live bioluminescence and near-infrared imaging of optic neuritis and encephalitis in the experimental autoimmune encephalomyelitis (EAE) model for multiple sclerosis in SJL/J mice.

마우스의 다발성 경화증의 EAE 모델에서 시신경염 및 뇌 염증의 생물 발광 및 근적외선 영상

Experimental autoimmune encephalomyelitis (EAE) in SJL/J mice is a model for relapsing-remitting multiple sclerosis (RRMS). Clinical EAE scores describing ...

A Quantitative Sensory Testing Paradigm to Obtain Measures of Pain Processing in Patients Undergoing Breast Cancer Surgery

Chronic pain following surgery, persistent postsurgical pain, is an important highly prevalent condition contributing to significant symptom burden and lower quality of life. Persistent postsurgical pain is relatively refractory to treatment hence generating a high need for preventive strategies and treatments. Therefore, the identification of patients at risk of developing persistent pain is an area of active ongoing research. Recently it was demonstrated that peri-operative disruptions in central pain processing may be able to predict persistent postsurgical pain at long term follow-up in breast cancer patients. The aim of the current report is to present a short protocol to obtain pain thresholds to different stimuli at multiple sites and a measure of endogenous analgesia in breast cancer patients. We have used this method successfully in a clinical context and detail some representative results from a clinical study.

Persistent postsurgical pain may be related to changes in pain processing. By assessing pain in response to standardized stimuli, changes in pain processing can be elucidated. We present methods to obtain pain thresholds to different stimuli and a measure of endogenous analgesia in patients undergoing breast cancer surgery.

유 방 암 수술을 받은 환자에서 처리 하는 고통의 측정을 얻기 위해 양적 감각 테스트 패러다임

Chronic pain following surgery, persistent postsurgical pain, is an important highly prevalent condition contributing to significant symptom burden and ...

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic demand. Reactive hyperemia (in response to a brief period of tissue ischemia) is an independent predictor of cardiovascular events and provides important insight into vascular health and vasodilatory capacity. Skeletal muscle oxidative capacity is equally important in health and disease, as it determines the energy supply for myocellular processes. Here, we describe a simple, non-invasive approach using near-infrared spectroscopy to assess each of these major clinical endpoints (reactive hyperemia, neurovascular coupling, and muscle oxidative capacity) during a single clinic or laboratory visit. Unlike Doppler ultrasound, magnetic resonance images/spectroscopy, or invasive catheter-based flow measurements or muscle biopsies, our approach is less operator-dependent, low-cost, and completely non-invasive. Representative data from our lab taken together with summary data from previously published literature illustrate the utility of each of these end-points. Once this technique is mastered, application to clinical populations will provide important mechanistic insight into exercise intolerance and cardiovascular dysfunction.

Here, we describe a simple, non-invasive approach using near-infrared spectroscopy to assess reactive hyperemia, neurovascular coupling and skeletal muscle oxidative capacity in a single clinic or laboratory visit.

골격 근육 혈관 결합, 산화 용량 및 Microvascular 함수 '원스톱 쇼핑' 근처-적외선 분광학

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic ...

A New Best Practice for Validating Tail Vein Injections in Rat with Near-infrared-Labeled Agents

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part of many experimental procedures where reagents need to be introduced directly into the bloodstream. Unwittingly, the injection can be subcutaneous, possibly altering the scientific outcomes. Utilizing a nanoemulsion-based biological probe with an incorporated near-infrared fluorescent (NIRF) dye, this method offers the capability of imaging a successful tail vein injection in vivo. With the use of a NIRF imager, images are taken before and after the injection of the agent. An acceptable IV injection is then qualitatively or quantitatively determined based on the intensity of the NIRF signal at the site of injection.

Here we present a method to validate tail vein injections in rats by utilizing near-infrared fluorescence imaging data from dyes incorporated into agents or biological probes. The tail is imaged before and after the injection, the fluorescent signal is quantified, and an assessment of the injection quality is made.

근처-적외선-표시 에이전트와 쥐의 꼬리 정 맥 주사의 유효성 검사에 대 한 새로운 좋습니다

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part ...