ABSTRACT
PURPOSE: To propose an innovative three-dimensional surface presentation of the optic nerve head (ONH) from the SPECTRALIS optical coherence tomography (OCT) device. METHOD: A dataset of OCT ONH files from eight glaucoma follow-up patients was obtained. The set consisted of OCT ONH images for 20 right eyes (OD) and 17 left eyes (OS). Preprocessing steps followed with OCT reconstruction procedures were designed. The three-dimensional (3D) surface rendering was generated for all OCT ONH images. A set of eight International Organization for Standardization (ISO) roughness parameters were calculated to assess the disparities in the 3D ONH surface morphology during follow-up visit. RESULTS: The 3D ONH surface presents a new OCT display to ophthalmology; so, the physician can examine the surface morphology of the OCT ONH region. The 3D ONH surface's shape varied noticeably during follow-up visits in glaucoma patients. The percentage disparity of ONH surface roughness's can be as small as 3% or almost zero, but it can be as large as 56% or 100%. CONCLUSIONS: The approximation of OCT ONH 3D surface is feasible; it may possibly be beneficial to ophthalmology. It allows ophthalmologist to perceive the entire changes in the ONH surface morphology during the follow-up attendances; so, it can be used to observe patient health. The ISO roughness measurements are suggestive complementary factors to observe the alterations in the OCT ONH region.
Subject(s)
Glaucoma/diagnosis , Imaging, Three-Dimensional , Optic Disk/diagnostic imaging , Retinal Ganglion Cells/pathology , Tomography, Optical Coherence/methods , Adolescent , Adult , Aged , Child , Female , Follow-Up Studies , Glaucoma/physiopathology , Humans , Intraocular Pressure/physiology , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Young AdultABSTRACT
This paper explores the benefits of interactive three-dimensional (3D) visualization of stimuli using a computer aided detection (CAD) system of pulmonary embolisms (PEs), on computed tomography pulmonary angiography (CTPA) views. We designed a new CAD method that prompts the PE sites on CTPA views; we then utilized two interactive approaches of 3D visualization to assess CAD performance. This collaboration allows different methodologies to be used to assess PE-CAD performance, by comparison with the common method in which radiologists are prompted with CAD stimuli directly on the CTPA views. Both 3D approaches are based on the voxel size of the CTPA examination, and consider the acquisition settings. A set of ten retrospective CTPA cases were collected, with different acquisition parameters, in terms of voxel size and spatial resolution. 3D visualization CAD performance was examined by an experienced radiologist. Both 3D visualization methods proved to have a constructive impact on improving CAD performance. The rate of true positive (TP) responses increased by 27%; while the rate of false positive (FP) responses dropped by 31%. We concluded that evaluation of PE-CAD performance utilizing interactive 3D visualization could increase or ascertain the correct rate of TP stimuli, as well as noticeably reduce FP responses.
Subject(s)
Angiography/methods , Computer Graphics , Imaging, Three-Dimensional/methods , Pulmonary Embolism/diagnosis , Radiographic Image Interpretation, Computer-Assisted , Tomography, X-Ray Computed/methods , Humans , Pulmonary Embolism/diagnostic imaging , Retrospective StudiesABSTRACT
PURPOSE: To investigate monitoring slope-based features of the optic nerve head (ONH) cup as open-angle glaucoma (OAG) occurs. METHOD: A dataset of 46 retrospective OCT cases was acquired from the SPECTRALIS Heidelberg Engineering OCT device. A set of five parameters, which are based on the ONH cup-incline, are measured on the OAG and normal subjects in the dataset. Then, three new ONH cup-shape indices were deduced. The ONH cup-incline parameters and ONH cup-shape indices are analyzed to estimate their clinical value. RESULTS: The statistical difference between measurements on normal and glaucoma eyes was remarkably significant for all of the analyzed parameters and indices (p value < 0.001). CONCLUSIONS: The geometric shape of the ONH cup can be transferred to numerical parameters and indices. The proposed ONH cup-incline parameters and ONH cup-shape indices have shown suggestive clinical value to identify the development of OAG. As OAG appears, the top ONH cup-incline parameters decrease while the bottom ONH cup-incline parameters increase. The ONH cup-shape indices suggest capability to discriminate OAG from normal eyes.