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1.
Med Phys ; 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33651407

RESUMO

PURPOSE: Magnetic Resonance Imaging (MRI)-guided transperineal prostate biopsy has been practiced since the early 2000s. The technique often suffers from targeting error due to deviation of the needle as a result of physical interaction between the needle and inhomogeneous tissues. Existing needle guide devices, such as a grid template, do not allow choosing an alternative insertion path to mitigate the deviation because of their limited degree-of-freedom (DoF). This study evaluates how an angulated needle insertion path can reduce needle deviation and improve needle placement accuracy. METHODS: We extended a robotic needle-guidance device (Smart Template) for in-bore MRI-guided transperineal prostate biopsy. The new Smart Template has a 4-DoF needle guiding mechanism allowing a translational range of motion of 65 mm and 58 mm along the vertical and horizontal axis, and a needle rotational motion around the vertical and horizontal axis +30º and a vertical rotational range of [-30º,+10º], respectively. We defined a path planning strategy, which chooses between straight and angulated insertion paths depending on the anatomical structures on the potential insertion path. We performed 1) a set of experiments to evaluate the device positioning accuracy outside the MR-bore, and 2) an in vivo experiment to evaluate the improvement of targeting accuracy combining straight and angulated insertions in animal models (swine, n = 3). RESULTS: We analyzed 46 in vivo insertions using either straight or angulated insertions paths. The experiment showed that the proposed strategy of selecting straight or angulated insertions based on the subject's anatomy outperformed the conventional approach of just straight insertions in terms of targeting accuracy (2.4 mm [1.3-3.7] vs. 3.9 mm [2.4-5.0] {Median[IQR]}); p = 0.041 after the bias correction). CONCLUSION: The in vivo experiment successfully demonstrated that an angulated needle insertion path could improve needle placement accuracy with a path planning strategy that takes account of the subject-specific anatomical structures.

2.
PLoS One ; 16(2): e0245334, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33571221

RESUMO

Providing surgical margin information during breast cancer surgery is crucial for the success of the procedure. The margin is defined as the distance from the tumor to the cut surface of the resection specimen. The consensus among surgeons and radiation oncologists is that there should be no tumor left within 1 to maximum 2 mm from the surface of the surgical specimen. If a positive margin remains, there is substantial risk for tumor recurrence, which may also result in potentially reduced cosmesis and eventual need for mastectomy. In this paper we report a novel multimodal optical imaging instrument based on combined high-resolution confocal microscopy-optical coherence tomography imaging for assessing the presence of potential positive margins on surgical specimens. Since rapid specimen analysis is critical during surgery, this instrument also includes a fluorescence imaging channel to enable rapid identification of the areas of the specimen that have potential positive margins. This is possible by specimen incubation with a cancer specific agent prior to imaging. In this study we used a quenched contrast agent, which is activated by cancer specific enzymes, such as urokinase plasminogen activators (uPA). Using this agent or a similar one, one may limit the use of high-resolution optical imaging to only fluorescence-highlighted areas for visualizing tissue morphology at the sub-cellular scale and confirming or ruling out cancer presence. Preliminary evaluation of this technology was performed on 20 surgical specimens and testing of the optical imaging findings was performed against histopathology. The combination of the three imaging modes allowed for high correlation between optical image analysis and histological ground-truth. The initial results are encouraging, showing instrument capability to assess margins on clinical specimens with a positive predictive value of 1.0 and a negative predictive value of 0.83.

3.
J Cutan Pathol ; 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989842

RESUMO

BACKGROUND: Accurate basal cell carcinoma (BCC) subtyping is requisite for appropriate management, but non-representative sampling occurs in 18% to 25% of biopsies. By enabling non-invasive diagnosis and more comprehensive sampling, integrated reflectance confocal microscopy-optical coherence tomography (RCM-OCT) may improve the accuracy of BCC subtyping and subsequent management. We evaluated RCM-OCT images and histopathology slides for the presence of two key features, angulation and small nests and cords, and calculated (a) sensitivity and specificity of these features, combined and individually, for identifying an infiltrative BCC subtype and (b) agreement across modalities. METHODS: Thirty-three RCM-OCT-imaged, histopathologically-proven BCCs (17 superficial and/or nodular; 16 containing an infiltrative component) were evaluated. RESULTS: The presence of angulation or small nests and cords was sufficient to identify infiltrative BCC on RCM-OCT with 100% sensitivity and 82% specificity, similar to histopathology (100% sensitivity, 88% specificity, kappa = 0.82). When both features were present, the sensitivity for identifying infiltrative BCC was 100% using either modality and specificity was 88% on RCM-OCT vs 94% on histopathology, indicating near-perfect agreement between non-invasive and invasive diagnostic modalities (kappa = 0.94). CONCLUSIONS: RCM-OCT can non-invasively identify key histopathologic features of infiltrative BCC offering a possible alternative to traditional invasive biopsy.

4.
J Cancer ; 11(20): 6019-6024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922542

RESUMO

The increasing rate of incidence and prevalence of basal cell carcinomas (BCCs) worldwide, combined with the morbidity associated with conventional surgical treatment has led to the development and use of alternative minimally invasive non-surgical treatments. Biopsy and pathology are used to guide BCC diagnosis and assess margins and subtypes, which then guide the decision and choice of surgical or non-surgical treatment. However, alternatively, a noninvasive optical approach based on combined reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) imaging may be used. Optical imaging may be used to guide diagnosis and margin assessment at the bedside, and potentially facilitate non-surgical management, along with long-term monitoring of treatment response. Noninvasive imaging may also complement minimally invasive treatments and help further reduce morbidity. In this paper, we highlight the current state of an integrated RCM/OCT imaging approach for diagnosis and triage of BCCs, as well as for assessing margins, which therefore may be ultimately used for guiding therapy.

5.
Opt Lett ; 45(4): 909-912, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058502

RESUMO

In this Letter, we report a low-cost, portable, two-photon excitation fluorescence microscopy imager that uses a fiber-based approach for both femtosecond supercontinuum (SC) generation and light delivery to the optical head. The SC generation is based on a tapered polarization-maintaining photonic crystal fiber that uses pre-chirped femtosecond narrowband pulses to generate a coherent SC spectrum with a bandwidth of approximately 300 nm. Using this approach, high-power, near-transform-limited, wavelength-selectable SC pulses are generated and directly delivered to the imaging optical head. Preliminary testing of this imager on brain slices is presented, demonstrating a high signal-to-noise ratio and sub-cellular imaging capabilities to a depth of approximately 200 µm. These results demonstrate the suitability of the technology for ex vivo and potentially in vivo cellular-level biomedical imaging applications.


Assuntos
Luz , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Fibras Ópticas , Fenômenos Ópticos , Desenho de Equipamento , Dinâmica não Linear
7.
Sci Rep ; 9(1): 17795, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780755

RESUMO

Multichannel (multicolor) imaging has become a powerful technique in biology research for performing in vivo neuronal calcium imaging, colocalization of fluorescent labels, non-invasive pH measurement, and other procedures. We describe a novel add-on approach for simultaneous multichannel optical microscopy based on simple wedge prisms. Our device requires no alignment and is simple, robust, user-friendly, and less expensive than current commercial instruments based on switchable filters or dual-view strategies. Point spread function measurements and simulations in Zemax indicate a reduction in resolution in the direction orthogonal to the wedge interface and in the axial direction, without introducing aberration. These effects depend on the objective utilized and are most significant near the periphery of the field of view. We tested a two-channel device on C. elegans neurons in vivo and demonstrated comparable signals to a conventional dual-view instrument. We also tested a four-channel device on fixed chick embryo Brainbow samples and identified individual neurons by their spectra without extensive image postprocessing. Therefore, we believe that this technology has the potential for broad use in microscopy.


Assuntos
Caenorhabditis elegans/citologia , Microscopia/métodos , Neurônios/metabolismo , Imagem Óptica/métodos , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Embrião de Galinha , Corantes Fluorescentes/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/metabolismo , Microscopia/instrumentação , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Imagem Óptica/instrumentação
8.
Biomed Opt Express ; 10(9): 4450-4461, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31565501

RESUMO

Voice disorders affect a large number of adults in the United States, and their clinical evaluation heavily relies on laryngeal videostroboscopy, which captures the medial-lateral and anterior-posterior motion of the vocal folds using stroboscopic sampling. However, videostroboscopy does not provide direct visualization of the superior-inferior movement of the vocal folds, which yields important clinical insight. In this paper, we present a novel technology that complements videostroboscopic findings by adding the ability to image the coronal plane and visualize the superior-inferior movement of the vocal folds. The technology is based on optical coherence tomography, which is combined with videostroboscopy within the same endoscopic probe to provide spatially and temporally co-registered images of the mucosal wave motion, as well as vocal folds subsurface morphology. We demonstrate the capability of the rigid endoscopic probe, in a benchtop setting, to characterize the complex movement and subsurface structure of the aerodynamically driven excised larynx models within the 50 to 200 Hz phonation range. Our preliminary results encourage future development of this technology with the goal of its use for in vivo laryngeal imaging.

9.
Arch Pathol Lab Med ; 143(9): 1058-1068, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31295016

RESUMO

CONTEXT.­: The rapid evolution of optical imaging modalities in recent years has opened the opportunity for ex vivo tissue imaging, which has significant implications for surgical pathology practice. These modalities have promising potential to be used as next-generation digital microscopy tools for examination of fresh tissue, with or without labeling with contrast agents. OBJECTIVE.­: To review the literature regarding various types of ex vivo optical imaging platforms that can generate digital images for tissue recognition with potential for utilization in anatomic pathology clinical practices. DATA SOURCES.­: Literature relevant to ex vivo tissue imaging obtained from the PubMed database. CONCLUSIONS.­: Ex vivo imaging of tissues can be performed by using various types of optical imaging techniques. These next-generation digital microscopy tools have a promising potential for utilization in surgical pathology practice.


Assuntos
Microscopia/métodos , Imagem Óptica/métodos , Patologia Cirúrgica/métodos , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Humanos , Microscopia/instrumentação , Microscopia/tendências , Microscopia Confocal , Microscopia de Fluorescência , Microscopia Ultravioleta , Microscopia Óptica não Linear , Imagem Óptica/instrumentação , Imagem Óptica/tendências , Patologia Clínica/métodos , Patologia Cirúrgica/instrumentação , Patologia Cirúrgica/tendências , Tomografia de Coerência Óptica
10.
Biomed Opt Express ; 10(1): 167-180, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30775091

RESUMO

The platform described here combines the non-invasive measurement of the retina/choroid structure and ocular blood flow based on optical coherence tomography (OCT) and wide-field semi-quantitative global flow visualization using line-scanning Doppler flowmetry (LSDF). The combination of these two imaging modalities within the same platform enables comprehensive assessment of blood flow in the retina and choroid in animals and human subjects for diagnostic purposes. Ultra-widefield vasculature visualization is demonstrated here for the first time without injecting additional contrast agents and based only on the motion of particles within the vasculature.

11.
J Biomed Opt ; 23(10): 1-4, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30350490

RESUMO

It is hypothesized that the local, viscoelastic (time-dependent) properties of the airway are important to accurately model and ultimately predict dynamic airway collapse in airway obstruction. Toward this end, we present a portable, endoscopic, swept-source anatomical optical coherence tomography (aOCT) system combined with a pressure catheter to capture local airway dynamics in vivo during respiration. aOCT scans were performed in the airways of a mechanically ventilated pig under paralysis with dynamic and static ventilation protocols. Validation of dynamic aOCT luminal cross-sectional area (CSA) measurements against Cine CT, obtained during the same exam, showed an aggregate difference of 15 % ± 3 % . aOCT-derived CSA obtained in the in vivo trachea also exhibited hysteresis as a function of pressure, depicting the viscoelastic nature of the airway wall. The volumetric imaging capabilities were validated by comparing aOCT- and CT-derived geometries of the porcine airway spanning nine generations from the trachea to the bronchioles. The ability to delineate regional differences in airway viscoelastic properties, by measuring airway deformation using aOCT combined with intraluminal pressure, paves the way to patient-specific models of dynamic airway collapse.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Pulmão/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Traqueia/diagnóstico por imagem , Animais , Fenômenos Biomecânicos/fisiologia , Elasticidade/fisiologia , Desenho de Equipamento , Pulmão/fisiologia , Pressão , Respiração , Suínos , Tomografia Computadorizada por Raios X , Traqueia/fisiologia
12.
JAMA Dermatol ; 154(10): 1175-1183, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30140851

RESUMO

Importance: The limited tissue sampling of a biopsy can lead to an incomplete assessment of basal cell carcinoma (BCC) subtypes and depth. Reflectance confocal microscopy (RCM) combined with optical coherence tomography (OCT) imaging may enable real-time, noninvasive, comprehensive three-dimensional sampling in vivo, which may improve the diagnostic accuracy and margin assessment of BCCs. Objective: To determine the accuracy of a combined RCM-OCT device for BCC detection and deep margin assessment. Design, Setting, and Participants: This pilot study was carried out on 85 lesions from 55 patients referred for physician consultation or Mohs surgery at Memorial Sloan Kettering Skin Cancer Center in Hauppauge, New York. These patients were prospectively and consecutively enrolled in the study between January 1, 2017, and December 31, 2017. Patients underwent imaging, with the combined RCM-OCT probe, for previously biopsied, histopathologically confirmed BCCs and lesions clinically or dermoscopically suggestive of BCC. Only patients with available histopathologic examination after imaging were included. Main Outcomes and Measures: Improvements in sensitivity, specificity, and diagnostic accuracy for BCC using the combined RCM-OCT probe as well as the correlation between OCT-estimated depth and histopathologically measured depth were investigated. Results: In total, 85 lesions from 55 patients (27 [49%] were female and 28 [51%] were male with a median [range] age of 59 [21-90] years) were imaged. Imaging was performed on 25 previously biopsied and histopathologically confirmed BCCs and 60 previously nonbiopsied but clinically or dermoscopically suspicious lesions. Normal skin and BCC features were correlated and validated with histopathologic examination. In previously biopsied lesions, residual tumors were detected in 12 of 25 (48%) lesions with 100% sensitivity (95% CI, 73.5%-100%) and 23.1% specificity (95% CI, 5.0%-53.8%) for combined RCM-OCT probe. In previously nonbiopsied and suspicious lesions, BCCs were diagnosed in 48 of 60 (80%) lesions with 100% sensitivity (95% CI, 92.6%-100%) and 75% specificity (95% CI, 42.8%-94.5%). Correlation was observed between depth estimated with OCT and depth measured with histopathologic examination: the coefficient of determination (R2) was 0.75 (R = 0.86; P < .001) for all lesions, 0.73 (R = 0.85; P < .001) for lesions less than 500 µm deep, and 0.65 (R = 0.43; P < .001) for lesions greater than 500 µm deep. Conclusions and Relevance: Combined RCM-OCT imaging may be prospectively used to comprehensively diagnose lesions suggestive of BCC and triage for treatment. Further validation of this device must be performed on a larger cohort.


Assuntos
Carcinoma Basocelular/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Basocelular/patologia , Feminino , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Imagem Multimodal , Projetos Piloto , Estudos Prospectivos , Sensibilidade e Especificidade , Pele/patologia , Neoplasias Cutâneas/patologia , Adulto Jovem
13.
Biomed Opt Express ; 9(2): 694-704, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29552405

RESUMO

We report the development and the pre-clinical testing of a new technology based on optical coherence tomography (OCT) for investigating tissue composition at the tip of the core biopsy needle. While ultrasound, computed tomography, and magnetic resonance imaging are routinely used to guide needle placement within a tumor, they still do not provide the resolution needed to investigate tissue cellularity (ratio between viable tumor and benign stroma) at the needle tip prior to taking a biopsy core. High resolution OCT imaging, however, can be used to investigate tissue morphology at the micron scale, and thus to determine if the biopsy core would likely have the expected composition. Therefore, we implemented this capability within a custom-made biopsy gun and evaluated its capability for a correct estimation of tumor tissue cellularity. A pilot study on a rabbit model of soft tissue cancer has shown the capability of this technique to provide correct evaluation of tumor tissue cellularity in over 85% of the cases. These initial results indicate the potential benefit of the OCT-based approach for improving the success of the core biopsy procedures.

14.
J Biomed Opt ; 22(7): 76006, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28697233

RESUMO

We present a hand-held implementation and preliminary evaluation of a combined optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) probe for detecting and delineating the margins of basal cell carcinomas (BCCs) in human skin

Assuntos
Carcinoma Basocelular/diagnóstico por imagem , Microscopia Confocal , Tomografia de Coerência Óptica , Estudos Transversais , Humanos , Projetos Piloto
15.
Biomed Opt Express ; 8(4): 2195-2209, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28736665

RESUMO

Quantification of airway compliance can aid in the diagnosis and treatment of obstructive airway disorders by detecting regions vulnerable to collapse. Here we evaluate the ability of a swept-source anatomic optical coherence tomography (SSaOCT) system to quantify airway cross-sectional compliance (CC) by measuring changes in the luminal cross-sectional area (CSA) under physiologically relevant pressures of 10-40 cmH2O. The accuracy and precision of CC measurements are determined using simulations of non-uniform rotation distortion (NURD) endemic to endoscopic scanning, and experiments performed in a simplified tube phantom and ex vivo porcine tracheas. NURD simulations show that CC measurements are typically more accurate than that of the CSAs from which they are derived. Phantom measurements of CSA versus pressure exhibit high linearity (R2>0.99), validating the dynamic range of the SSaOCT system. Tracheas also exhibited high linearity (R2 = 0.98) suggestive of linear elasticity, while CC measurements were obtained with typically ± 12% standard error.

16.
Biomed Opt Express ; 7(2): 238-50, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26977336

RESUMO

We report the development of a novel otoscopy probe for assessing middle ear anatomy and function. Video imaging and phase-sensitive optical coherence tomography are combined within the same optical path. A sound stimuli channel is incorporated as well to study middle ear function. Thus, besides visualizing the morphology of the middle ear, the vibration amplitude and frequency of the eardrum and ossicles are retrieved as well. Preliminary testing on cadaveric human temporal bone models has demonstrated the capability of this instrument for retrieving middle ear anatomy with micron scale resolution, as well as the vibration of the tympanic membrane and ossicles with sub-nm resolution.

18.
Retin Cases Brief Rep ; 10(4): 302-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26735319

RESUMO

PURPOSE: To elucidate the location of pathological changes in multiple evanescent white dot syndrome (MEWDS) with the use of multimodal adaptive optics (AO) imaging. METHODS: A 5-year observational case study of a 24-year-old female with recurrent MEWDS. Full examination included history, Snellen chart visual acuity, pupil assessment, intraocular pressures, slit lamp evaluation, dilated fundoscopic exam, imaging with Fourier-domain optical coherence tomography (FD-OCT), blue-light fundus autofluorescence (FAF), fundus photography, fluorescein angiography, and adaptive-optics optical coherence tomography. RESULTS: Three distinct acute episodes of MEWDS occurred during the period of follow-up. Fourier-domain optical coherence tomography and adaptive-optics imaging showed disturbance in the photoreceptor outer segments (PR OS) in the posterior pole with each flare. The degree of disturbance at the photoreceptor level corresponded to size and extent of the visual field changes. All findings were transient with delineation of the photoreceptor recovery from the outer edges of the lesion inward. Hyperautofluorescence was seen during acute flares. Increase in choroidal thickness did occur with each active flare but resolved. CONCLUSION: Although changes in the choroid and RPE can be observed in MEWDS, Fourier-domain optical coherence tomography, and multimodal adaptive optics imaging localized the visually significant changes seen in this disease at the level of the photoreceptors. These transient retinal changes specifically occur at the level of the inner segment ellipsoid and OS/RPE line. En face optical coherence tomography imaging provides a detailed, yet noninvasive method for following the convalescence of MEWDS and provides insight into the structural and functional relationship of this transient inflammatory retinal disease.


Assuntos
Imagem Multimodal , Óptica e Fotônica/métodos , Doenças Retinianas/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Feminino , Angiofluoresceinografia , Humanos , Microscopia Confocal , Imagem Multimodal/métodos , Doenças Retinianas/fisiopatologia , Adulto Jovem
19.
Opt Lett ; 39(24): 6807-10, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25503002

RESUMO

We present a new method for generating micron-scale OCT images of interstitial tissue with a hand scanning probe and a linear optical encoder that senses probe movement relative to a fixed reference point, i.e., tissue surface. Based on this approach, we demonstrate high resolution optical imaging of biological tissues through a very long biopsy needle. Minor artifacts caused by tissue noncompliance are corrected using a software algorithm which detects the simple repetition of the adjacent A-scans. This hand-scanning OCT imaging approach offers the physician the freedom to access imaging sites of interest repeatedly.


Assuntos
Retroalimentação , Tomografia de Coerência Óptica/instrumentação , Algoritmos , Animais , Processamento de Imagem Assistida por Computador
20.
J Biomed Opt ; 19(11): 116005, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25375634

RESUMO

We present portable preclinical low-coherence interference (LCI) instrumentation for aiding fine needle aspiration biopsies featuring the second-generation LCI-based biopsy probe and an improved scoring algorithm for tissue differentiation. Our instrument and algorithm were tested on 38 mice with cultured tumor mass and we show the specificity, sensitivity, and positive predictive value of tumor detection of over 0.89, 0.88, and 0.96, respectively.


Assuntos
Biópsia por Agulha Fina/métodos , Processamento de Imagem Assistida por Computador/métodos , Interferometria/métodos , Tecido Adiposo/química , Algoritmos , Animais , Linhagem Celular Tumoral , Humanos , Neoplasias Mamárias Experimentais/química , Camundongos , Músculo Esquelético/química , Curva ROC
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