Biz Ulusal Bilim Vakfı (KARİYER CBET-1055379) ve Ulusal Sağlık Enstitüleri (1RC4EY021357, 1R01EY019951) gelen cömert destek teşekkür ediyorum. Biz de Çin Burs Konseyi Wei Song destek için minnettarım.

1. Sistem Yapılandırması <ol><li> PAOM Subsystem <ol><li> Aydınlatma kaynağı: Nd: YAG lazer (SPOT-10-100, Elforlight Ltd, UK: 20 μJ / pulse; 2 nsec darbe süresi; 30 kHz maksimum darbe tekrarlama oranı). </li><li> Bir beta-baryum-borat ile 532 nm frekans iki katına 1064 nm&#39;de çıkış lazer edilir (BBO) kristal (CasTech, San Jose, CA). Bir lazer hattı ayna tarafından daha fazla bölünmüş sonra, 532 nm ışık tek modlu fiber optik (P1-460A-FC-5, Thorlabs) aracılığıyla teslim edilir ve 1064 nm lazer tetikleyen bir fotodiyot (DET10A, Thorlabs) tarafından kaydedilen PA sinyal alımı. </li><li> Tek modlu fiber optik üzerinden gelen lazer ışığı bir galvanometre (GM, QS-7, Nutfield Teknolojisi) ve bir teleskop yapılandırması tarafından retina üzerine teslim edilir (f1 = 75 mm ve f2 = 14 mm, Edmund Optik) 6. </li><li> Bir odaklanmamış iğne dönüştürücü (40 MHz merkez frekanslı, 16 MHz bant genişliği, 0.4 × 0.4 mm 2 aktif elemanın büyüklüğü, NIH Kaynak centeUltrasonik Dönüştürücü Teknolojileri, Southern California Üniversitesi) için r retinanın oluşturulan PA sinyalleri algılamak için göz kapağı ile temas ettirilir. Ultrasonik jel (Sonotech) iyi akustik kuplaj için dönüştürücü ucu ve hayvan gözkapağı arasına uygulanır. </li><li> PA sinyali iki amplifikatör (ZFL-500LN +, Mini-devreleri ve 5073PR, Olympus) ile amplifiye edilir ve (CS14200, Gage Uygulamalı) bir veri toplama kurulu tarafından sayısallaştırılmıştır. </li></ol></li><li> SD-OCT Subsystem <ol><li> Düşük tutarlılık ışık kaynağı: Bir genişbant süper-Işıklı diyot (IPSDD0804, InPhenix; merkez dalgaboyu:;: 50 nm 6-dB bant genişliği 840 nm) 6 mikron aksiyal çözünürlük belirler. </li><li> Yakın kızılötesi ışığı 50 ile kol ve doku kolundan başvurmak için ayrılmıştır × 50 özelleştirilmiş single-mode fiber bağlantı elemanı (OZ Optics). </li><li> Sıcak bir ayna (FM02, Thorlabs) tarafından PAOM aydınlatıcı ışığı ile birleştirerek sonra OCT örnek kol aynı tarama ve teslimat optik wi paylaşmaktadırinci PAOM 6. </li><li> Bir ev inşa spektrometre line-scan CCD kamera (Aviiva SM2, E2V) 24 kHz A-line oranı sağlayan SD-OCT parazit sinyalleri kaydetmek için kullanılır. Tipik bir spektrometre tasarımı önceden çeşitli yayınlar, 11 ve lif çiftli SD-OCT spektrometre elde edilebilen şu anda ticari olarak temin edilebilir. SD-OCT hassasiyeti 90 dB daha iyi olduğu ölçülür. </li></ol></li><li> Şema Tarama <ol><li> Galvanometre tarama Hızlı 2-D raster de PAOM lazer atış ve OCT spektrometre sinyal edinimi hem tetikleyen bir analog çıkış kartı (PCI-6731, National Instruments) tarafından kontrol edilir. Sonuç olarak, PAOM ve OCT içinde alt veri toplama senkronize edilir. </li><li> PAOM veri toplama bir fotodiyot kayıt PAOM lazer dizisi (1.1.2 bakınız) tarafından tetiklenir. </li><li> 3-D volümetrik görüntüler veya 2-D fundus görüntüleri (256 256 B-tarama görüntüleri inşa edilir B başına A-hatları) Görüntü tarayın. </li></ol></li></ol> 2. Sistem Yerleşimi <ol><li> BBO kristal frekans çiftleme verim ve tek modlu fiber optik bağlantı verimliliğini en üst düzeye. PAOM aydınlatıcı ışığı optimize ederken personel göz koruması için LG3 gözlüğü (Thorlabs) giyin. </li><li> Çap olarak 2.0 mm kadar bir elyaf PAOM çıkış lazer paralelleştirmek. </li><li> Koaksiyel olmak PAOM ve SD-OCT kombine aydınlatma ışıkları hizalayın. </li><li> ~ 0.8 mW ışık sondalama ~ 40 nJ / darbe ve SD-OCT de PAOM ikaz ışığı ayarlayın, her ikisi de 6,12 güvenli göz olduğu bildirilmektedir. </li></ol> 3. Vivo Multimodaller Retina Imaging&#39;de <ol><li> Bir saydam polipropilen kutu için sıçan aktarın ve izofluran (Phoenix Pharmaceutical, Inc) ve normal% 1.5 &#39;lik bir konsantrasyonda, hava ve 2.0 litre / 10 dk için dak&#39; lık bir akış oranı ile bir karışım hayvan anestetize. </li><li> Bir homema yılında anestezi sıçan dizginlemekde beş-eksenli ayarlanabilir serbestlik (Şekil 1) ve bir ısıtma pedi (Repti term, Zoomed Laboratories, Inc) ile ~ 37 ° C &#39;de vücut sıcaklığını tutmak ile tutucu. Deney boyunca% 1.0 konsantrasyonda ve 1.5 litre / dk debi ile karışık izofluran ve normal hava teneffüs gaz ile anestezi koruyun. </li><li> Bir cerrahi makas kullanarak kirpik Kes 1% Tropikamid oftalmik solüsyonu ile öğrenciler dilate ve% 0.5 Tetrakain hidroklorür oftalmik solüsyon kullanarak iris sfinkter kas felç. Sıçan gözün kornea dehidratasyon ve katarakt oluşumunu önlemek için her dakika için yapay gözyaşı damlaları (Systane, Alcon Laboratories, Inc) uygulayın. Görüntüleme sırasında pulse oksimetre (8.600 V, Nonin Medical, MN) tarafından hayvan kalp hızı, solunum ve kan oksijenlenme izleyin. </li><li> SD-OCT aydınlatıcı ışığı açın ve ~ 0.8 mW olmak problama ışığı denetleyin. </li><li> Galvanometre tarama etkinleştirin. SD-OCT ışınlama ışık dağıtım hizalayınsıçan retina üzerine ve beş eksenli hayvan sahibi ayarlayarak ilgi retina bölgesi (ROI) belirlemek. ROI farklı araştırma ihtiyaçlarına göre seçilmelidir ederken Burada, optik disk kasıtlı, görüş alanının merkezinde yer alıyor. </li><li> Ayrıca en iyi optik odaklama elde edilene kadar her ikisi de tarama yönü (raster tarama yönünü değiştirerek) retina kesitinin SD-OCT görüntüleme özellikleri optimize etmek için hayvan sahibi ayarlayın. </li><li> Beş eksenli ayarlanabilir platform üzerinde iğne dönüştürücü hazırlayın, dönüştürücü ucu ultrasonik jel bir damla uygulayın ve nazikçe hayvan gözkapağı Dönüştürücü ucu başvurun. </li><li> Harici tetikleme moduna PAOM lazer ayarlayın, galvanometre tarama başlatın ve hayvan retinanın PAOM kesitsel görüntü gerçek zamanlı görüntü etkinleştirin. PAOM görüntü arada, en iyi sinyal-gürültü oranı (SNR) var ve kadar dikkatlice dönüştürücü yönünü ayarlamak, bir eşit dist gösterirHer iki tarama yönde Pensilvanya genlik desenleri ributed. </li><li> Tarama parametrelerini ayarlayın, ve SD-OCT ve PAOM aynı anda retina görüntüleme yapmak. SD-OCT ile PAOM off-line üç boyutlu görüntüleri yeniden. Bizim yeniden kodlar Matlab yazılmış ve üç boyutlu görselleştirme (Volview, Kitware) ücretsiz bir uing sağlandı. SD-OCT rekonstrüksiyon algoritması 11. Ref bulunabilir ve PAOM rekonstrüksiyon algoritması Ref bulunabilir. 6 ve Ref. 13. Gerekirse) 3.7 prosedürleri) -3.9 tekrarlayın. </li><li> Deneyden sonra, SD-OCT sondalama ışığını kapatmak derhal tutucudan hayvan çıkarın ve doğal uyanana kadar sıcak tutun. Kurtarmak için gözler için ekstra bir saat karanlık bir ortamda hayvan tutun. Hayvan anestezi ve görüntüleme edinilmesi dahil bütün deney süresince, deneyimli bir operatör için en az 30 dk. </li></ol>

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Tüm deney hayvan prosedürleri Northwestern Üniversitesi Kurumsal Hayvan Bakım ve Kullanım Kurulu tarafından onaylanmıştır.

Burada, SD-OCT ile kombine PAOM kullanılarak sıçan gözleri vivo retina görüntüleme eşzamanlı üzerine ayrıntılı bir talimat sunuyoruz. Optik-saçılma tabanlı SD-OCT, belki de, retina görüntüleme 3 klinik &quot;altın standart&quot; olduğunu; ancak, retinada optik soğurma algılamak için duyarlı değildir. Yeni geliştirilen PAOM retinanın 6 optik soğurma özellikleri sağlar sadece optik emme tabanlı oftalmik görüntüleme yöntemidir. Hemoglobin ve melani...

integrated photoacoustic ophthalmoscopy and spectral-domain optical coherence tomography

Klinik tanı ve majör oküler hastalıkların temel soruşturma Hem büyük ölçüde çeşitli non-invaziv oftalmik görüntüleme teknolojilerinden yararlanmak. Retina görüntüleme gibi fundus fotoğraflarında 1, konfokal tarayıcı laser oftalmoskopi (cSLO) 2, ve optik koherens tomografi (OCT) 3 gibi yöntemleri, hastalık sergilenir ve ilerlemeler, izleme ve yeni tedavi stratejilerinin geliştirilmesine önemli katkıları var. Mevcut Ancak, ağırlıklı retinadan geri yansıyan fotonlar güveniyor. Bunun bir sonucu olarak, genellikle kuvvetle retina patofizyolojisi ile ilişkili olan statü retina optik emme özellikleri, geleneksel bir görüntüleme teknolojisi ile erişilemez. Photoacoustic oftalmoskopi (PAOM) yüksek hassasiyet 4-7 ile göz optik soğurma karşıtlıklar algılama izin yükselen bir retina görüntüleme yöntemidir. PAOM nan yılındaosecond lazer darbeleri öğrenci ile teslim ve göz kapağına iliştirilmiş bir odaklanmamış ultrasonik sensör tarafından algılanır photoacoustic (PA) sinyalleri, ikna etmek için posterior göz genelinde taranır. Çünkü hemoglobin ve melanin güçlü optik absorpsiyon, PAOM non-invaziv görüntüleme retinal ve koroidal vasculatures ve yüksek kontrastlı 6,7 de retina pigment epiteli (RPE) melanin yeteneğine sahiptir. Daha da önemlisi, iyi gelişmiş spektroskopik photoacoustic görüntüleme 5,8 dayanan, PAOM, diyabetik retinopati gibi birçok kör hastalıkların 9 fizyolojisi ve patolojisi okuyan kritik olabilir retina damarlarında hemoglobin oksijen satürasyonu, eşlemek için bir potansiyele sahiptir ve neovasküler yaşa bağlı makula dejenerasyonu. Dahası, mevcut tek optik soğurma tabanlı oftalmik görüntüleme yöntemi olmanın, PAOM köklü klinik oftalmik görüntüleme te ile entegre edilebilirchniques birden fazla optik zıtlıklar 6,10 göre gözün daha kapsamlı anatomik ve fonksiyonel değerlendirmeler elde etmek için. Bu çalışmada, optik soğurma ve retinanın saçılma özelliklerini hem de ortaya çıkar sıçan, in vivo retina görüntüleme eşzamanlı için PAOM ve spectral-domain OCT (SD-OCT) entegre. Sistem yapılandırması, sistem uyumu ve görüntüleme edinimi sunulmaktadır.

Şekil 2 SD-OCT ve PAOM bir albino sıçanlar (A ve B) ve sırasıyla bir pigmente sıçan (C ve D) &#39;de elde edilen ve eş zamanlı olarak 2-D fundus görüntüler gösterir. SD-OCT fundus görüntüleri (Şekil 2A ve 2C) ise, retina damarlarında ışık problama hemoglobin emilimi nedeniyle koyu bir görünüme sahip. Retinal damar (Şekil 2B içinde RV) ek olarak, PAOM çünkü eksik RPE melanin albino göz içinde koroidal vascu...

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 oftalmoloji (PAOM), optik-soğurma tabanlı görüntüleme yöntemi, şu anda mevcut oftalmik görüntüleme teknolojileri retinanın tamamlayıcı değerlendirilmesini sağlar. Biz sıçanlarda eşzamanlı multimodal retina görüntüleme için spektral domain optik koherens tomografi (SD-OCT) ile entegre PAOM kullanılarak rapor.

Entegre Photoacoustic Oftalmoskopi ve Spektral-domain optik koherens tomografi

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 Görüntüleme.  Northwestern University. Photoacoustic oftalmoloji (PAOM), optik-soğurma tabanlı görüntüleme yöntemi, şu anda mevcut oftalmik görüntüleme teknolojileri retinanın tamamlayıcı değerlendirilmesini sağlar. Biz sıçanlarda eşzamanlı multimodal retina görüntüleme için spektral domain optik koherens tomografi (SD-OCT) ile entegre PAOM kullanılarak rapor.

Video: 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.

Üç boyutlu optik çözünürlük foto akustik Mikroskopi

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

Biyomühendislik

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.

Sirkülasyon Melanom Hücreler foto akustik flowmetre kullanarak Algılama ve İzolasyonu

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.

Yerli, Fibröz Uzun Aralığı ve Bölümlere Uzun Aralığı Kollajen in vitro sentezi olarak

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.

Foto akustik Sistografi

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.

Altın nanorods İçeren Hücresel Araçların Hazırlama ve foto akustik Analizi

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.

Bilgisayarlı Tomografi ve Osteogenezi-anjiyogenez bağlamalar Optik Görüntüleme Kranial Kemik Otogreftlerin ve allogreft Entegrasyon değerlendirmek için

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.

Için değiştirilebilir Akustik ve Optik Çözünürlük Fotoakustik Mikroskopi<emIn vivo</em&gt; Küçük Hayvan Kan Vaskülatür Görüntüleme

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.

Için yüksek performanslı bir Kompakt Fotoakustik Tomografi Sistemi<emIn vivo</em&gt; Küçük Hayvanlı Beyin Görüntüleme

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.

Eğik tarama Lazer Ophthalmoscopy (oSLO) ve optik koherens tomografi (OCT) tarafından Multimodal hacimsel Retina Görüntüleme

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.

Geri dönüşlü optik koherens tomografi kullanarak parçalanabilir iskele tabanlı doku mühendisliği kan damarı gelişimi izleme

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