Optical Coherence Tomography Catheter Research Articles

In-Vitro MPI-guided IVOCT catheter tracking in real time for motion artifact compensation.

Using 4D magnetic particle imaging (MPI), intravascular optical coherence tomography (IVOCT) catheters are tracked in real time in order to compensate for image artifacts related to relative motion. Our approach demonstrates the feasibility for bimodal IVOCT and MPI in-vitro experiments. During IVOCT imaging of a stenosis phantom the catheter is tracked using MPI. A 4D trajectory of the catheter tip is determined from the MPI data using center of mass sub-voxel strategies. A custom built IVOCT imaging adapter is used to perform different catheter motion profiles: no motion artifacts, motion artifacts due to catheter bending, and heart beat motion artifacts. Two IVOCT volume reconstruction methods are compared qualitatively and quantitatively using the DICE metric and the known stenosis length. The MPI-tracked trajectory of the IVOCT catheter is validated in multiple repeated measurements calculating the absolute mean error and standard deviation. Both volume reconstruction methods are compared and analyzed whether they are capable of compensating the motion artifacts. The novel approach of MPI-guided catheter tracking corrects motion artifacts leading to a DICE coefficient with a minimum of 86% in comparison to 58% for a standard reconstruction approach. IVOCT catheter tracking with MPI in real time is an auspicious method for radiation free MPI-guided IVOCT interventions. The combination of MPI and IVOCT can help to reduce motion artifacts due to catheter bending and heart beat for optimized IVOCT volume reconstructions.

Steerable OCT catheter for real-time assistance during teleoperated endoscopic treatment of colorectal cancer.

When detected early, colorectal cancer can be treated with minimally invasive flexible endoscopy. However, since only specialized experts can delineate margins and perform endoscopic resections of lesions, patients still often undergo colon resections. To better assist in the performance of surgical tasks, a robotized flexible interventional endoscope was previously developed, having two additional side channels for surgical instrument. We propose to enhance the imaging capabilities of this device by combining it with optical coherence tomography (OCT). For this purpose, we have developed a new steerable OCT instrument with an outer diameter of 3.5 mm. The steerable instrument is terminated with a 2 cm long transparent sheath to allow three-dimensional OCT imaging using a side-focusing optical probe with two external scanning actuators. The instrument is connected to an OCT imaging system built around the OCT Axsun engine, with a 1310 nm center wavelength swept source laser and 100 kHz A-line rate. Once inserted in one of the side channels of the robotized endoscope, bending, rotation and translation of the steerable OCT instrument can be controlled by a physician using a joystick. Ex vivo and in vivo tests show that the novel, steerable and teleoperated OCT device enhances dexterity, allowing for inspection of the surgical field without the need for changing the position of the main endoscope.

Innovative use of optical coherence tomography catheter via nipple orifice: a case report of first intraductal images of florid ductal hyperplasia.

The incidence of malignancy in patients with pathologic nipple discharge (PND) varies from 1% to 23% (1). Currently, methylene blue dye or lacrimal probe guided isolated duct excision is still the standard treatment of PND. Majority of those patients are not with cancer-involved ducts and have unnecessary surgery to reveal the definitive histopathology. With conventional imaging, it is not possible to understand whether those ducts involve cancer or not (2). It is well established that ductoscopy is a novel technique that could diagnose a single papilloma; however, it is insufficient to diagnose an in situ or invasive cancer (3,4). Currently, optical coherence tomography (OCT) is used as a non-invasive imaging test that utilizes light waves to capture cross-sectional pictures of retina or coronary arteries (5). In our novel approach, a miniaturized OCT catheter is inserted into the breast ductal system via the nipple orifices to provide detailed real-time imaging of breast ductal epithelial anatomy.

A FBG-OCT Catheter to Reconstruct Vascular Shape in Intravascular Optical Coherence Tomography

We propose a novel fiber Bragg grating (FBG)-optical coherence tomography (OCT) catheter to reconstruct vascular shape by intravascular OCT imaging of the actual curvature as well as the bending direction of the vascular in real-time. Compared with the traditional OCT catheter, the FBG-OCT catheter uses the FBG encapsulated with half- sectioned stainless-steel tube as a flexural sensitive component. With the 360-degree rotation of the catheter, the encapsulated FBG will produce maximum tension and maximum compression at the bend of the blood vessel, and then get the solution of the curvature and direction of the bending catheter as well as the OCT imaging simultaneously. To test the proposed catheter for real-time measurement, a bending calibration system and a vascular prosthesis model to simulate the actual vascular bending morphology are manufactured through three-dimension (3D) printing. Experimental data shows that the new FBG-OCT catheter can acquire the OCT images and FBG bending parameters real-timely and synchronously. Further, the obtained bending parameters and OCT images are used to restore the morphology of the vascular model, which will provide corrective data for accurate measurements of further vascular plaques, blood flow, and intravascular pressure.

Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study.

BACKGROUNDChronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of life. Radiofrequency ablation (RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease management.AIMTo study feasibility of optical coherence tomography angiography (OCTA) for investigating subsurface vascular alterations in CRP and response to RFA treatment.METHODSTwo patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahigh-speed optical coherence tomography (OCT) system over 15 OCT/colonoscopy visits (2 normal patients, 5 RFA-naïve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, without requiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic scoring.RESULTSOCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 μm in diameter versus abnormal heterogenous enlarged arterioles and venules > 200 μm in diameter were visualized in the rectal submucosa. Abnormal mucosal vasculature occurred in 0 of 2 normal patients and 3 of 5 RFA-naïve patients, while abnormal submucosal vasculature occurred more often, in 1 of 2 normal patients and 5 of 5 RFA-naïve patients. After RFA treatment, vascular abnormalities decreased, with abnormal mucosal vasculature observed in 0 of 8 RFA-follow-up visits and abnormal submucosal vasculature observed in only and 2 of 8 RFA-follow-up visits.CONCLUSIONOCTA visualizes depth-resolved microvascular abnormalities in CRP, allowing assessment of superficial features which are endoscopically visible as well as deeper vasculature which cannot be seen endoscopically. OCTA/OCT of the rectum can be performed in conjunction with, or independently from endoscopy. Further studies are warranted to investigate if OCTA/OCT can elucidate pathophysiology of CRP or improve management.

Balloon catheter-based radiofrequency ablation monitoring in porcine esophagus using optical coherence tomography.

We present a microscopic image guidance platform for radiofrequency ablation (RFA) using a clinical balloon-catheter-based optical coherence tomography (OCT) system, currently used in the surveillance of Barrett's esophagus patients. Our integrated thermal therapy delivery and monitoring platform consists of a flexible, customized bipolar RFA electrode array designed for use with a clinical balloon OCT catheter and a processing algorithm to accurately map the thermal coagulation process. Non-uniform rotation distortion was corrected using a feature tracking-based technique, which enables robust, frame-to-frame analysis of the temporal fluctuation of the complex OCT signal. With proper noise calibration, precise delineation of the thermal therapy zone was demonstrated using cumulative complex differential variance in porcine esophagus ex vivo with the integrated OCT-RFA system, as validated by nitroblue tetrazolium chloride (NBTC) histology. The ability to directly and accurately visualize the thermal coagulation process at high resolution is critical to the precise delivery of thermal energy to a wide range of epithelial lesions.

Techniques to Optimize the Use of Optical Coherence Tomography: Insights from the Manufacturer and User Facility Device Experience (MAUDE) Database.

Optical coherence tomography (OCT) is a high-resolution intravascular imaging modality used to assess coronary arteries and as an adjunctive tool for optimization of percutaneous coronary interventions. Overall, the rate of complications and adverse events related to intravascular imaging is low. Limited data exist on the most commonly reported complications and modes of failure related to the use of OCT. Therefore, we analyzed the post-marketing surveillance data from the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database to assess the reported complications and failure modes for OCT and reviewed techniques to optimize device use. The MAUDE database was queried for all event reports involving coronary OCT devices. Two independent reviewers identified 49 device reports included in the final analysis. Modes of failure and device-related patient complications were assessed. Of the 49 cases with reported device-related issues, 6.1% involved malfunction prior to insertion of the OCT catheter, and 30.6% of reported events did not result in an associated patient-related adverse event. The most commonly reported adverse events included coronary dissection and difficulty removing the catheter within a previously stented segment. No events of contrast-induced nephropathy were reported. Findings from the MAUDE database highlight the modes of device-related events associated with OCT. Device issues are uncommon, and as a result, users should be aware of optimal techniques to prevent and minimize adverse events related to device use.

Lumen boundaries extracted from coronary computed tomography angiography on computed fractional flow reserve (FFRCT): validation with optical coherence tomography.

The aim of this study was to evaluate the accuracy of minimum lumen area (MLA) by coronary computed tomography angiography (cCTA) and its impact on fractional flow reserve (FFRCT). Fifty-seven patients (118 lesions, 72 vessels) who underwent cCTA and optical coherence tomography (OCT) were enrolled. OCT and cCTA were co-registered and MLAs were measured with both modalities. FFROCT was calculated using OCT-updated models with cCTA-based lumen geometry replaced by OCT-derived geometry. Lesions were grouped by Agatston score (AS) and minimum lumen diameter (MLD) using the OCT catheter and guidewire size (1.0 mm) as a threshold. For all lesions, the average absolute difference between cCTA and OCT MLA was 0.621±0.571 mm2. Pearson correlation coefficients between cCTA and OCT MLAs in lesions with low-intermediate and high AS were 0.873 and 0.787, respectively (both p<0.0001). Irrespective of AS score, excellent correlations were observed for MLA (r=0.839, p<0.0001) and FFR comparisons (r=0.918, p<0.0001) in lesions with MLD ≥1.0 mm but not for lesions with MLD <1.0 mm. The spatial resolution of cCTA or calcification does not practically limit the accuracy of lumen boundary identification by cCTA or FFRCT calculations for MLD ≥1.0 mm. The accuracy of cCTA MLA could not be adequately assessed for lesions with MLD <1.0 mm.

Intraluminal three-dimensional optical coherence tomography – a tool for imaging of the Eustachian tube?

The cause of Eustachian tube dysfunction often remains unclear. Therefore, this study aimed to examine the feasibility and possible diagnostic use of optical coherence tomography in the Eustachian tube ex vivo. Two female blackface sheep cadaver heads were examined bilaterally. Three conditions of the Eustachian tube were investigated: closed (resting position), actively opened and stented. The findings were compared (and correlated) with segmented histological cross-sections. Intraluminal placement of the Eustachian tube with the optical coherence tomography catheter was performed without difficulty. Regarding the limited infiltration depth of optical coherence tomography, tissues can be differentiated. The localisation of the stent was accurate as was the lumen. The application of optical coherence tomography in the Eustachian tube under these experimental conditions is considered to be a feasible, rapid and non-invasive diagnostic method, with possible diagnostic value for determining the luminal shape and superficial lining tissue of the Eustachian tube.

Optical coherence tomography-verified longer balloon inflation time may provide better stent apposition and optimal index parameters.

Incomplete stent expansion and inadequate apposition predispose to stent thrombosis following percutaneous coronary intervention. Recent studies have shown that increasing the duration of balloon inflation during stent employment was beneficial. Thus, the balloon inflation time required for optimal stent expansion and apposition in patients receiving second-generation drug-eluting stents (DES) were determined using optical coherence tomography (OCT). Between April 2014 and March 2015, 38patients (28men, 10women; mean age 60.5 ± 11.4years) with stable angina pectoris due to single significant de novo coronary artery stenosis were prospectively enrolled. All patients were administered aspirin and clopidogrel and received weight-adjusted intravenous unfractionated heparin. Images of basal lesions were obtained using the C7XR LightLab Dragonfly OCT catheter. Expansion and apposition parameters improved with increasing duration of balloon inflation (30 s or 60 s) with nominal pressure (12 atm). Mean lesion length was 19.8 ± 7.6 mm. Mean stent diameter and length were 2.8 ± 0.36 mm and 24.9 ± 7.6 mm, respectively. With deployment of astent at nominal pressure with conventional duration, inadequate stent expansion and malapposition frequently occurred as detected by OCT; however, aballoon inflation duration of 60 s markedly improved stent expansion and apposition parameters without significant complications.

Nano-optic endoscope for high-resolution optical coherence tomography in vivo.

Acquisition of high-resolution images from within internal organs using endoscopic optical imaging has numerous clinical applications. However, difficulties associated with optical aberrations and the trade-off between transverse resolution and depth-of-focus significantly limit the scope of applications. Here, we integrate a metalens, with the ability to modify the phase of incident light at sub-wavelength level, into the design of an endoscopic optical coherence tomography catheter (termed nano-optic endoscope) to achieve near diffraction-limited imaging through negating non-chromatic aberrations. Remarkably, the tailored chromatic dispersion of the metalens in the context of spectral interferometry is utilized to maintain high-resolution imaging beyond the input field Rayleigh range, easing the trade-off between transverse resolution and depth-of-focus. We demonstrate endoscopic imaging both in resected human lung specimens and in sheep airways in vivo. The combination of the superior resolution and higher imaging depth-of-focus of the nano-optic endoscope will likely increase the clinical utility of endoscopic optical imaging.

All-optical dual photoacoustic and optical coherence tomography intravascular probe

Intravascular imaging in percutaneous coronary interventions can be an invaluable tool in the treatment of coronary artery disease. It is of significant interest to provide molecular imaging contrast that is complementary to structural contrast provided by optical coherence tomography (OCT) and intravascular ultrasound imaging (IVUS). In this study, we developed a dual-modality intravascular imaging probe comprising a commercial OCT catheter and a high sensitivity fiber optic ultrasound sensor, to provide both photoacoustic (PA) and OCT imaging. With PA imaging, the lateral resolution varied from 18 μm to 40 μm; the axial resolution was consistently in the vicinity of 45 μm. We demonstrated the clinical potential of the probe with 2-D circumferential PA and OCT imaging, and with multispectral PA imaging.

Preoperative assessment of computerized tomography angiography to predict success for crossing long Trans-Atlantic Inter-Society Consensus D lesions using the optical coherence tomography catheter.

Objectives Optical coherence tomography chronic total occlusion catheter, the Ocelot (Avinger Inc., Redwood City, CA), has been utilized to cross Trans-Atlantic Inter-Society Consensus D lesions. This study evaluated the preoperative computerized tomography angiography of chronic total occlusions in the superficial femoral artery to predict clinical success. Methods We reviewed all patients who underwent lower extremity procedures with the Ocelot catheter from June 2014 to August 2016. Patients who had a preoperative computerized tomography angiography were evaluated. Final outcomes, plaque morphology, lesion length, calcium surface area, lesion location, and patient characteristics were analyzed. Results A total of 107 patients underwent lower extremity interventions with the Ocelot catheter. Seventy patients had a preoperative computerized tomography angiography scan prior to lower extremity intervention and 77% (54) had Trans-Atlantic Inter-Society Consensus D lesions that were crossed. Mean age was 62.8 years and 68.6% were male. Mean chronic total occlusion length was 182.7 mm (170.8 mm crossed vs. 222.6 mm uncrossed, p = 0.03). Calcium distribution differed significantly ( p<.01): circumferential (14.8 vs. 12.5%); eccentric (85 vs. 62.5%); and complete calcium occlusion (0 vs. 25%) for lesions that were crossed and uncrossed, respectively. Significant differences ( p<.0001) were found when calcium occlusion was less than 50% (87 vs. 31%), 51-75% (9.3 vs. 31.2%), and 76-100% (3.7 vs. 37.5%). Total calcium length in crossed lesion was 51.6 mm, and 92.8 mm in uncrossed lesions ( p = 0.10). No significant differences were noted for patient gender, occlusion location (proximal, middle, and distal superficial femoral artery), and kidney function. Conclusion The Ocelot catheter is an effective method to cross long Trans-Atlantic Inter-Society Consensus D lesions. Superficial femoral artery lesions longer than 17 cm and focal plaque morphology, specifically a total cross-sectional area of calcium and a calcium surface area greater than 50% were most predictive of failure to cross Trans-Atlantic Inter-Society Consensus D superficial femoral artery lesions. Computerized tomography angiography is an effective tool to predict success for crossing chronic total occlusions using optical coherence tomography technology and a critical consideration for patient selection.

Imaging collector channel entrance with a new intraocular micro-probe swept-source optical coherence tomography.

To describe the use of a newly developed side-viewing catheter probe to provide the cross-sectional images of collector channel entrance (CCE), achieved by swept-source optical coherence tomography (SS-OCT). A side-viewing SS-OCT catheter probe was developed that has a core probe diameter of 0.15mm and an outer diameter of 0.25mm, for the purpose of imaging CCEs within eye globe. Cadaver eyes harvested from swine and human were used to demonstrate its feasibility. For porcine eyes, the probe imaged the CCE by accessing the region of the aqueous plexus (AP) as well as along the inner wall (IW) of the trabecular meshwork (TM). For human eyes, the CCE images were captured by placing the probe within the lumen of the Schlemm's canal (SC) and along its IW. With the optical coherence tomography (OCT) catheter probe, the CCE is well delineated as optically empty areas within the highly scattering sclera. In porcine eyes, images captured in the region of the AP demonstrate a large cavity with delicate tissue strands around the probe. The CCE can be identified at the outer margin of the AP. When imaged along the IW, the TM is discernable but difficult to be distinguished from the AP. In the human limbal regions, when placed within the lumen of the SC, the catheter probe fully occupies the potential space. TM is highly compact. The CCE can be identified at the outer wall of the SC. When imaged along the IW of TM, the SC and CCE can be identified. The intraocular SS-OCT catheter probe is feasible to provide the CCE images, indicating useful clinical applications to assist glaucoma surgery.

Mother-and-child catheter-facilitated optical coherence tomography: A novel approach to improve intracoronary imaging.

Our aim was to prospectively analyze the usefulness of mother-and-child catheter approach with the GuideLiner® (GL) catheter extension system to overcome some potential limitations associated with the use of optical coherence tomography (OCT). We included consecutive patients referred to our institution for coronary angiogram in whom OCT image acquisition was obtained using GL. From February 2015 to May 2016, a total of 19 procedures (18 patients) were prospectively included. In more than two thirds of the procedures, the OCT catheter was unable to cross the coronary stenosis prior to the use of GL. The right coronary artery was the most frequently involved coronary vessel (63%). The main reason for using GL (47% of cases) was poor engagement of the coronary ostium and lack of support of the guiding catheter (47%). Eventually, in 18 out of 19 procedures, a good quality OCT image was obtained and, when indicated, successful percutaneous coronary intervention with stent implantation was performed. Of note, there were no serious complications related to the use of GL during OCT imaging. Optical coherence tomography through a catheter extension system is a useful technique able to overcome some of the limitations associated with this imaging technique ensuring adequate blood clearance and thus optimal image quality.

Astigmatism corrected common path probe for optical coherence tomography.

Optical coherence tomography (OCT) catheters for intraluminal imaging are subject to various artifacts due to reference-sample arm dispersion imbalances and sample arm beam astigmatism. The goal of this work was to develop a probe that minimizes such artifacts. Our probe was fabricated using a single mode fiber at the tip of which a glass spacer and graded index objective lens were spliced to achieve the desired focal distance. The signal was reflected using a curved reflector to correct for astigmatism caused by the thin, protective, transparent sheath that surrounds the optics. The probe design was optimized using Zemax, a commercially available optical design software. Common path interferometric operation was achieved using Fresnel reflection from the tip of the focusing graded index objective lens. The performance of the probe was tested using a custom designed spectrometer-based OCT system. The probe achieved an axial resolution of 15.6 μm in air, a lateral resolution 33 μm, and a sensitivity of 103 dB. A scattering tissue phantom was imaged to test the performance of the probe for astigmatism correction. Images of the phantom confirmed that this common-path, astigmatism-corrected OCT imaging probe had minimal artifacts in the axial, and lateral dimensions. In this work, we developed an astigmatism-corrected, common path probe that minimizes artifacts associated with standard OCT probes. This design may be useful for OCT applications that require high axial and lateral resolutions. Lasers Surg. Med. 49:312-318, 2017. © 2016 Wiley Periodicals, Inc.

Dextran or Saline Can Replace Contrast for Intravascular Optical Coherence Tomography in Lower Extremity Arteries

Purpose: To examine the hypothesis that alternative flush media could be used for lower extremity optical coherence tomography (OCT) imaging in long lesions that would normally require excessive use of contrast. Methods: The OPTical Imaging Measurement of Intravascular Solution Efficacy (OPTIMISE) trial was a single-center, prospective study (ClinicalTrials.gov identifier NCT01743872) that enrolled 23 patients (mean age 68±11 years; 14 men) undergoing endovascular intervention involving the superficial femoral artery. Four flush media (heparinized saline, dextran, carbon dioxide, and contrast) were used in succession in random order for each image pullback. Quality was defined as ≥270° visualization of vessel wall layers from each axial image. Mean proportions (± standard deviation) of image quality for each flush medium were assessed using 1-way analysis of variance and are reported with the 95% confidence intervals (CI). Results: Four OCT catheters failed, leaving 19 patients who completed the OCT imaging protocol; from this cohort, 51 highest quality runs were selected for analysis. Average vessel diameter was 3.99±1.01 mm. OCT imaging allowed 10- to 15-μm resolution of the lumen border, with diminishing quality as vessel diameter increased. Plaque characterization revealed fibrotic lesions. Mean proportions of image quality were dextran 87.2%±12% (95% CI 0.81 to 0.94), heparinized saline 74.3%±24.8% (95% CI 0.66 to 0.93), contrast 70.1%±30.5% (95% CI 0.52 to 0.88), and carbon dioxide 10.0%±10.4% (95% CI 0.00 to 0.26). Dextran, saline, and contrast provided better quality than carbon dioxide (p<0.001). Conclusion: OCT is feasible in peripheral vessels <5 mm in diameter. Dextran or saline flush media can allow lesion characterization, avoiding iodinated contrast. Carbon dioxide is inadequate for peripheral OCT imaging. Axial imaging may aid in enhancing durability of peripheral endovascular interventions.

Dynamic single gold nanoparticle visualization by clinical intracoronary optical coherence tomography.

The potential use of Gold Nanoparticles (GNPs) as contrast agents for clinical intracoronary frequency domain Optical Coherence Tomography (OCT) is here explored. The OCT contrast enhancement caused by GNPs of different sizes and morphologies has been systematically investigated and correlated with their optical properties. Among the different GNPs commercially available with plasmon resonances close to the operating wavelength of intracoronary OCT (1.3 µm), Gold Nanoshells (GNSs) have provided the best OCT contrast due to their largest scattering cross section at this wavelength. Clinical intracoronary OCT catheters are here demonstrated to be capable of three dimensional visualization and real-time tracking of individual GNSs. Results here included open an avenue to novel application of intravascular clinical OCT in combination with GNPs, such as real time evaluation of intravascular obstructions or pressure gradients.

Advances in Endoscopic Optical Coherence Tomography Catheter Designs

The use of endoscopic Optical Coherence Tomography (OCT) in the clinical setting has gained momentum in recent years. This is largely due to the advances in OCT catheter designs that are tailored to specific clinical applications. In this review, we summarize many of the designs currently used in patient studies, and additionally discuss a number of novel designs that are yet to be implemented and tested in the clinical setting. With advances in endoscopic OCT catheter designs, we are now beginning to uncover the true clinical potential of this technology particularly in screening, surveillance, biopsy guidance, diagnosis, and therapy-monitoring applications.

Optical Coherence Tomography Imaging for the Diagnosis of Airway Tumors In Vivo

SESSION TITLE: Lung Cancer Screening & Diagnosis Posters SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PM PURPOSE: Optical Coherence Tomography (OCT) is a non-contact optical imaging modality that provides tomographic images of tissue at resolutions comparable with architectural histology (<10 microns) to a depth of approximately 3mm. Using surgical and autopsy specimens, we have previously developed and validated OCT interpretation criteria using histological features for the detection and diagnosis of pulmonary malignancy. In this study we assess the accuracy of these criteria when applied to images collected in vivo. METHODS: OCT imaging was conducted in healthy subjects and in patients with known pulmonary malignancy. Imaging was performed during bronchoscopy using a custom OCT catheter passed through the working channel of a standard bronchoscope. Images of patients with biopsy confirmed lung cancer and those of normal healthy subjects were placed in a randomized test set and were reviewed by a blinded OCT reader and pathologist trained in the interpretation criteria. The reader was asked to identify the images as adenocarcinoma, squamous cell carcinoma, poorly differentiated tumor, or normal tissue. RESULTS: Of 19 patients (2 adenocarcinoma, 5 squamous cell carcinoma, 1 poorly differentiated carcinoma, and 11 normal) that were reviewed, 89.5% were diagnosed correctly. Our reader was able to detect adenocarcinoma with a sensitivity of 100% and specificity of 94% and to detect squamous cell carcinoma with a sensitivity of 80% and specificity of 100%. The overall sensitivity and specificity in detecting lung cancer (adenocarcinoma, squamous cell, and poorly differentiated carcinoma) was 87.5% and 90.9% respectively. CONCLUSIONS: Our pilot study demonstrates that OCT has good sensitivity and specificity in the diagnosis of adenocarcinoma and squamous cell carcinoma involving airways. Further studies with a larger sample size are needed to better evaluate the true clinical potential of this imaging modality. CLINICAL IMPLICATIONS: OCT may serve a role as an adjunctive imaging modality in the detection and diagnosis of lung cancers involving airways. DISCLOSURE: Melissa Suter: Grant monies (from sources other than industry): National Institutes of Health grant numbers R01CA167827, R00CA134920. NinePoint Medical, Grant monies (from industry related sources): NinePoint Medical, Other: Dr Suter is an author on MGH owned patents that have been licensed to NinePoint Medical. The following authors have nothing to disclose: Christopher Manley, Lida Hariri, David Adams, Michael Lanuti, Colleen Channick, Colleen Keyes, Carla Lamb, John Beamis, David Riker, Josalyn Cho, R Harris, Andrew Luster, Benjamin Medoff Optical Coherence Tomography is not an approved therapy or diagnostic modality for diagnosis or treatment of lung cancer. Imaging of lung tumors in vivo with OCT is a novel technique.