High-resolution Full-field Optical Coherence Research Articles

Value of high-resolution full-field optical coherence tomography and dynamic cell imaging for one-stop rapid diagnosis breast clinic.

Full-field optical coherence tomography combined with dynamic cell imaging (D-FFOCT) is a new, simple-to-use, nondestructive, quick technique that can provide sufficient spatial resolution to mimic histopathological analysis. The objective of this study was to evaluate diagnostic performance of D-FFOCT for one-stop rapid diagnosis breast clinic. Dynamic full-field optical coherence tomography was applied to fresh, untreated breast and nodes biopsies. Four different readers (senior and junior radiologist, surgeon, and pathologist) analyzed the samples without knowing final histological diagnosis or American College of Radiology classification. The results were compared to conventional processing and staining (hematoxylin-eosin). A total of 217 biopsies were performed on 152 patients. There were 144 breast biopsies and 61 lymph nodes with 101 infiltrative cancers (49.27%), 99 benign lesions (48.29%), 3 ductal in situ carcinoma (1.46%), and 2 atypias (0.98%). The diagnostic performance results were as follow: sensitivity: 77% [0.7;0.82], specificity: 64% [0.58;0.71], PPV: 74% [0.68;0.78], and NPV: 75% [0.72;0.78]. A large image atlas was created as well as a diagnosis algorithm from the readers' experience. With 74% PPV and 75% NPV, D-FFOCT is not yet ready to be used in clinical practice to identify breast cancer. This is mainly explained by the lack of experience and knowledge of this new technic by the four lectors. By training with the diagnosis algorithm and the image atlas, radiologists could have better outcomes allowing quick detection of breast cancer and lymph node involvement. Deep learning could also be used, and further investigation will follow.

High-resolution full-field optical coherence tomography microscope for the evaluation of freshly excised skin specimens during Mohs surgery: A feasibility study.

Histopathology for tumor margin assessment is time-consuming and expensive. High-resolution full-field optical coherence tomography (FF-OCT) images fresh tissues rapidly at cellular resolution and potentially facilitates evaluation. Here, we define FF-OCT features of normal and neoplastic skin lesions in fresh ex vivo tissues and assess its diagnostic accuracy for malignancies. For this, normal and neoplastic tissues were obtained from Mohs surgery, imaged using FF-OCT, and their features were described. Two expert OCT readers conducted a blinded analysis to evaluate their diagnostic accuracies, using histopathology as the ground truth. A convolutional neural network was built to distinguish and outline normal structures and tumors. Of the 113 tissues imaged, 95 (84%) had a tumor (75 basal cell carcinomas [BCCs] and 17 squamous cell carcinomas [SCCs]). The average reader diagnostic accuracy was 88.1%, with a sensitivity of 93.7%, and a specificity of 58.3%. The artificial intelligence (AI) model achieved a diagnostic accuracy of 87.6 ± 5.9%, sensitivity of 93.2 ± 2.1%, and specificity of 81.2 ± 9.2%. A mean intersection-over-union of 60.3 ± 10.1% was achieved when delineating the nodular BCC from normal structures. Limitation of the study was the small sample size for all tumors, especially SCCs. However, based on our preliminary results, we envision FF-OCT to rapidly image fresh tissues, facilitating surgical margin assessment. AI algorithms can aid in automated tumor detection, enabling widespread adoption of this technique.

High-resolution full-field optical coherence microscopy using a broadband light-emitting diode.

High-resolution full-field optical coherence microscopy (FF-OCM) is demonstrated using a single broadband light-emitting diode (LED). The characteristics of the LED-illumination FF-OCM system are measured and compared to those obtained using a halogen lamp, the light source of reference in FF-OCM. Both light sources yield identical performance in terms of spatial resolution and detection sensitivity, using the same setup and camera. In particular, an axial resolution of 0.7 μm (in water) is reached. A Xenopus laevis tadpole and ex-vivo human skin have been imaged using both sources, resulting in similar images, showing for the first time that LEDs could favorably replace halogen lamps in high-resolution FF-OCM for biomedical imaging.

Large Field, High Resolution Full-Field Optical Coherence Tomography: A Pre-clinical Study of Human Breast Tissue and Cancer Assessment

We present a benchmark pilot study in which high-resolution Full-Field Optical Coherence Tomography (FF-OCT) was used to image human breast tissue and is evaluated to assess its ability to aid the pathologist’s management of intra-operative diagnoses. FF-OCT imaging safety was investigated and agreement between FF-OCT and routinely prepared histopathological images was evaluated. The compact setup used for this study provides 1 µm3 resolution and 200 µm imaging depth, and a 2.25 cm2 specimen is scanned in about 7 minutes. 75 breast specimens were imaged from 22 patients (21 women, 1 man) with a mean age of 58 (range: 25-83). Pathologists blind diagnosed normal/benign or malignant tissue based on FF-OCT images alone, diagnosis from histopathology followed for comparison. The contrast in the FF-OCT images is generated by intrinsic tissue scattering properties, meaning that no tissue staining or preparation is required. Major architectural features and tissue structures of benign breast tissue, including adipocytes, fibrous stroma, lobules and ducts were characterized. Subsequently, features resulting from pathological modification were characterized and a diagnosis decision tree was developed. Using FF-OCT images, two breast pathologists were able to distinguish normal/benign tissue from lesional with a sensitivity of 94% and 90%, and specificity of 75% and 79% respectively.

Simultaneous shape measurement and layers detection by means of low coherence interferometry and optical coherence tomography

In this paper authors show the application of low coherence interferometry and optical coherence tomography with non-Gaussian light source, which are applicable in simultaneous measurement of micromembrane and detection of layers deposited on silicon wafer. The exemplary measurement results obtained with laboratory setup are presented. Full Text: PDF References D. Huang, et al. "Optical coherence tomography", Science, Vol. 254, 1178 (1991). CrossRef A. Dubois, L. Vabre, A.C. Boccara and E.l Beaurepaire, "High-Resolution Full-Field Optical Coherence Tomography with a Linnik Microscope", Appl. Opt. Vol. 41, 805 (2002). CrossRef J.W. Goodman, Statistical Optics (John Wiley & Sons 1985). A. Harasaki, J. Schmit and J.C. Wyant, "Offset of Coherent Envelope Position Due to Phase Change on Reflection", Appl. Opt. Vol. 40, 2101 (2001). CrossRef G. Kieran, J. Larkin, "Efficient nonlinear algorithm for envelope detection in white light interferometry", J. Opt. Soc. Am. A, Vol. 13, 832 (1996). CrossRef A. Hirabayashi, H. Ogawa and K. Kitagawa, "Fast Surface Profiler by White-Light Interferometry by use of a New Algorithm Based on Sampling Theory", Appl. Opt. Vol. 41, 4876 (2002). CrossRef J. Plucinski et al., "Optical low-coherence interferometry for selected technical applications", Bulletin of the Polish Academy of Sciences, Vol. 56, 155 (2008). DirectLink A. Pakula, L. Salbut, Fringe 2009, Springer, 358 (2009). S. Chen, A.W. Palmer, "Fringe order identification in optical fibre white-light interferometry using centroid algorithm method", Electronics Lett., Vol. 28, 553, (1992). CrossRef A. Sabac, C. Gorecki and M. Jozwkik, "Design, testing, and calibration of an integrated Mach-Zehnder-based optical read-out architecture for MEMS characterization", Proc SPIE, VOL. 5458, 141 (2004). DirectLink

High-resolution full-field optical coherence microscopy using a Mirau interferometer for the quantitative imaging of biological cells

In this paper quantitative imaging of biological cells using high-resolution full-field optical coherence microscopy (FF-OCM) is reported. The FF-OCM was realized using a swept-source system, a Mirau interferometer, and a CCD camera (a two-dimensional detection unit). A Mirau-interferometric objective lens was used to generate the interferometric signal. The signal was analyzed by a Fourier analysis technique. Optically sectioned amplitude images and a quantitative phase map of biological cells such as onion skin and red blood cells (RBCs) are demonstrated. Further, the refractive index profile of the RBCs is also presented. For the 50× Mirau objective, the experimentally achieved axial and transverse resolution of the present system are 3.8 and 1.2 μm, respectively. The CCD provides parallel detection and measures enface images without X, Y, Z mechanical scanning.

Optical 3D-storage in sol–gel materials with a reading by optical coherence tomography-technique

We report on the recording of 3D optical memories in sol–gel materials by using a non-linear absorption effect. This effect induces a local change in optical properties of the material which is read and quantified with a high-resolution full-field optical coherence tomography setup. It is the first time that this technique is used for this purpose. Data recording was performed by focused picosecond (ps) single-pulse irradiation at 1064 nm with energy densities of 10 and 33 J/cm 2 per pulse.

High-resolution full-field optical coherence tomography with a Linnik microscope.

We describe an original microscope for high-resolution optical coherence tomography applications. Our system is based on a Linnik interference microscope with high-numerical-aperture objectives. Lock-in detection of the interference signal is achieved in parallel on a CCD by use of a photoelastic birefringence modulator and full-field stroboscopic illumination with an infrared LED. Transverse cross-section (en-face, or XY) images can be obtained in real time with better than 1-microm axial (Z) resolution and 0.5-microm transverse (XY) resolution. A sensitivity of approximately 80 dB is reached at a 1-image/s acquisition rate, which allows tomography in scattering media such as biological tissues.