The mathematical model for 3D reconstruction of ocular fundus images is constructed according to both the reduced eye model and the simplified model of fundus camera optical system. The relationship between the images of emmetropic and ametropic eye and the true shape of ocular fundus retina is analyzed, and then the mapping relationship from 2D ocular fundus plan image to 3D surface image is obtained. As a result, the real example of 3D reconstruction for ocular fundus images is given. The max visual field of ocular fundus image for three-dimensional reconstruction is decided by the max visual field angle of fundus camera, which limits a size of the visual field of 3D reconstruction image and a range of z axis. According to the formulas of 3D mapping, the 2D data of ocular fundus image is mapped to 3D data and then veins mapping is carried out; thereafter, the 3D surface image of ocular fundus can be drawn immediately. This method makes use of the existing 2D imaging equipments to provide 3D surface image of patient's ocular fundus, and can provide ophthalmologist with beneficial reference and help to their clinical diagnosis and treatment.
Fundus Oculi ; Humans ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods ; Models, Anatomic ; Models, Theoretical ; Ophthalmoscopy ; Photography ; methods

INTRODUCTIONFor many years, ophthalmologists have looked at the optic nerve head to evaluate the status of glaucoma. Clinical examination of the optic nerve head and retinal nerve fibre layer (RNFL) is however, subjective and sometimes variable. Recent developments in computer-based imaging technologies have provided a means of obtaining quantitative measurements of the optic nerve head topography and peripapillary retinal nerve fibre layer thickness.

METHODSMultiple searches using Medline were carried out. Additional searches were made using reference lists of published papers and book chapters.

RESULTSStudies involving three imaging technologies namely, confocal scanning laser ophthalmoscopy, scanning laser polarimetry and optical coherence tomography were reviewed. Overall, these technologies were reproducible and demonstrate good sensitivity and specificity in the range of 70 to 80%. Inclusion of age and ethnicity normative database will make these technologies more effective in screening and diagnosis. Quantitative measurements provide useful parameters for monitoring of patients.

CONCLUSIONThere is no consensus on the best technology for assessing structural damage in glaucomatous optic neuropathy. Therefore, as with any investigation, the clinician should exercise clinical correlation and judgment before instituting the appropriate treatment.

Female ; Humans ; Middle Aged ; Ophthalmoscopy ; methods ; Optic Nerve ; Retina ; Sensitivity and Specificity ; Tomography, Optical ; methods ; Tomography, Optical Coherence

This paper is aimed to fulfill a prototype system used to classify and retrieve retinal image automatically. With the content-based image retrieval (CBIR) technology, a method to represent the retinal characteristics mixing the fundus image color (gray) histogram with bright, dark region features and other local comprehensive information was proposed. The method uses kernel principal component analysis (KPCA) to further extract nonlinear features and dimensionality reduced. It also puts forward a measurement method using support vector machine (SVM) on KPCA weighted distance in similarity measure aspect. Testing 300 samples with this prototype system randomly, we obtained the total image number of wrong retrieved 32, and the retrieval rate 89.33%. It showed that the identification rate of the system for retinal image was high.
Algorithms ; Fundus Oculi ; Humans ; Image Processing, Computer-Assisted ; methods ; Information Storage and Retrieval ; methods ; Numerical Analysis, Computer-Assisted ; Ophthalmoscopy ; standards ; Pattern Recognition, Automated ; methods ; Retina ; pathology ; Retinal Vessels ; pathology

We investigated the case of a young man with blurred vision in his left eye. His visual acuity was slightly decreased, and ophthalmoscopy disclosed a gray-white lesion in the macula. He had no systemic or ocular history. On the visual field test, the threshold sensitivity was decreased in the corresponding region. Spectral domain optical coherence tomography (OCT) demonstrated a disruption in the photoreceptor inner and outer segment (IS/OS) junction and undulation of the retinal pigment epithelium (RPE) with backscattering. We re-examined the patient after two weeks and after three months without any treatment. Visual acuity and visual field results were gradually normalized, and OCT demonstrated the recovery of continuity in the photoreceptor IS/OS junction, as well as decreased RPE irregularity with minimal backscattering. We used spectral domain OCT instead of time domain OCT (OCT3) so that we could provide better image resolution of the acute retinal pigment epitheliitis (ARPE). Finally, we observed recovery of the functional and anatomical changes in the ARPE patient with a resolution of the condition within three months following the initial examination, using OCT and visual field tests.
Adolescent ; Humans ; Macula Lutea/pathology ; Male ; Ophthalmoscopy ; Recovery of Function ; Retinal Pigment Epithelium/*pathology/physiopathology ; Retinitis/*pathology/physiopathology ; Time Factors ; *Tomography, Optical Coherence/methods ; Visual Acuity ; Visual Fields

Autopsy by forensic pathologist is a main mean currently to determine the cause of sudden unexpected death. Retinal examination is important but seldom performed during a forensic autopsy for various reasons. The value of retina examination has not been recognized. With invention of ophthalmic endoscopy and its subsequent application in postmortem retina examination, it has proved to be useful adjunct to determine the cause of death and to estimate the postmortem interval.
Adult ; Autopsy ; Cause of Death ; Craniocerebral Trauma/pathology* ; Decompression Sickness/pathology* ; Female ; Forensic Pathology/methods* ; Humans ; Male ; Middle Aged ; Ophthalmoscopy ; Retina/pathology* ; Subarachnoid Hemorrhage/pathology* ; Syndrome ; Vitreous Hemorrhage/pathology*

Slit lamp bio-microscope image analysis system can provide objective and quantitative diagnosis evidences for ophthalmologists and make available efficient storing, management and intercourse of sufferer information and diagnosis results. In this paper, the system is discussed on its devices, software structure, analysis process and algorithm.
Algorithms ; Conjunctival Diseases ; diagnosis ; Corneal Diseases ; diagnosis ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Eye Diseases ; diagnosis ; Humans ; Image Enhancement ; instrumentation ; methods ; Image Interpretation, Computer-Assisted ; instrumentation ; methods ; Information Storage and Retrieval ; methods ; Ophthalmoscopy ; methods ; Software

A 53-year-old Asian woman was treated with hydroxychloroquine and chloroquine for lupus erythematosus. Within a few years, she noticed circle-shaped shadows in her central vision. Upon examination, the patient's visual acuity was 20 / 25 in both eyes. Humphrey visual field (HVF) testing revealed a central visual defect, and fundoscopy showed a ring-shaped area of parafoveal retinal pigment epithelium depigmentation. Fundus autofluorescence imaging showed a hypofluorescent lesion consistent with bull's eye retinopathy. Adaptive optics scanning laser ophthalmoscope (AO-SLO) revealed patch cone mosaic lesions, in which cones were missing or lost. In addition, the remaining cones consisted of asymmetrical shapes and sizes that varied in brightness. Unlike previous studies employing deformable mirrors for wavefront aberration correction, our AO-SLO approach utilized dual liquid crystal on silicon spatial light modulators. Thus, by using AO-SLO, we were able to create a photographic montage consisting of high quality images. Disrupted cone AO-SLO images were matched with visual field test results and functional deficits were associated with a precise location on the montage, which allowed correlation of histological findings with functional changes determined by HVF. We also investigated whether adaptive optics imaging was more sensitive to anatomical changes compared with spectral-domain optical coherence tomography.
Chloroquine/*adverse effects/therapeutic use ; Diagnosis, Differential ; Female ; Humans ; Image Enhancement/*methods ; Lupus Erythematosus, Systemic/drug therapy ; Macula Lutea/drug effects/*pathology ; Middle Aged ; Ophthalmoscopy/*methods ; Retinal Diseases/chemically induced/*diagnosis

A 53-year-old Asian woman was treated with hydroxychloroquine and chloroquine for lupus erythematosus. Within a few years, she noticed circle-shaped shadows in her central vision. Upon examination, the patient's visual acuity was 20 / 25 in both eyes. Humphrey visual field (HVF) testing revealed a central visual defect, and fundoscopy showed a ring-shaped area of parafoveal retinal pigment epithelium depigmentation. Fundus autofluorescence imaging showed a hypofluorescent lesion consistent with bull's eye retinopathy. Adaptive optics scanning laser ophthalmoscope (AO-SLO) revealed patch cone mosaic lesions, in which cones were missing or lost. In addition, the remaining cones consisted of asymmetrical shapes and sizes that varied in brightness. Unlike previous studies employing deformable mirrors for wavefront aberration correction, our AO-SLO approach utilized dual liquid crystal on silicon spatial light modulators. Thus, by using AO-SLO, we were able to create a photographic montage consisting of high quality images. Disrupted cone AO-SLO images were matched with visual field test results and functional deficits were associated with a precise location on the montage, which allowed correlation of histological findings with functional changes determined by HVF. We also investigated whether adaptive optics imaging was more sensitive to anatomical changes compared with spectral-domain optical coherence tomography.
Chloroquine/*adverse effects/therapeutic use ; Diagnosis, Differential ; Female ; Humans ; Image Enhancement/*methods ; Lupus Erythematosus, Systemic/drug therapy ; Macula Lutea/drug effects/*pathology ; Middle Aged ; Ophthalmoscopy/*methods ; Retinal Diseases/chemically induced/*diagnosis

Aicardi syndrome is a rare neurodevelopmental disease characterised by congenital chorioretinal lacunae, corpus callosum dysgenesis, seizures, polymicrogyria, cerebral callosum, chorioretinopathy and electroencephalogram abnormality. We present a case of Aicardi syndrome with callosal hypogenesis in a 4.5-month-old baby who presented with infantile spasms. Ophthalmoscopy revealed chorioretinal lacunae. The clinical and magnetic resonance imaging features were diagnostic of Aicardi syndrome.
Agenesis of Corpus Callosum ; diagnosis ; Aicardi Syndrome ; diagnosis ; Brain ; diagnostic imaging ; pathology ; Choroid ; abnormalities ; Cornea ; physiopathology ; Female ; Humans ; Infant ; Magnetic Resonance Imaging ; methods ; Malformations of Cortical Development ; diagnosis ; Ophthalmoscopy ; methods ; Radiography ; Retina ; abnormalities ; Spasms, Infantile ; diagnosis

PURPOSE: To investigate the morphologic changes in the outer retina of patients with cone dystrophy, using spectral-domain optical coherence tomography (SD-OCT). METHODS: The medical records of 15 cone dystrophy patients examined from January 2007 to January 2012 were reviewed retrospectively. All patients underwent ophthalmic evaluation including best-corrected visual acuity (BCVA), color vision testing, fundus examination, full-field standard electroretinography (ERG), multifocal (mf) ERG, and SD-OCT. Qualitative and quantitative SD-OCT data and ERG responses were analyzed and compared among the patient categories and the normal control group. RESULTS: There were 4 major categories of SD-OCT findings, based on the status of the ellipsoid portion of the photoreceptor inner segment (ISe), outer segment (OS) contact cylinder, and retinal pigment epithelium (RPE) layer. Category 0 showed no structural abnormalities. Category 1 showed foveal ISe loss and obscurity of the border between the ISe band and the external limiting membrane (ELM). Category 2 showed foveal thinning and focal foveal ISe disruption with an intact ELM. Category 3 showed foveal thickening and perifoveal disruption of the ISe layer. Category 1 to 3 showed OS contact cylinder layer absence and RPE thickening. The patients in category 0 tended to be younger (mean, 10.0 years) than those in categories 1 to 3 (mean, 17.6 years), although this difference was not statistically significant. Category 1 to 3 patients exhibited statistically significant thinning of the central retina and outer nuclear layer and thickening of the RPE layer relative to the category 0 and normal control group. There was a significant correlation between the central foveal thickness and BCVA in the patients with cone dystrophy. ERG and mfERG responses did not differ significantly among the different cone dystrophy categories. CONCLUSIONS: The morphologic features of cone dystrophy as revealed by SD-OCT, could be categorized as either normal or 1 of 3 different types of outer retinal changes. The presence of normal retinal structures in young cone dystrophy patients with functional impairment (category 0) indicates that electrophysiologic studies are superior to current imaging modalities for the early diagnosis of cone dystrophy. The characteristic SD-OCT findings in cone dystrophy patients may aid in differential diagnosis and be useful for future research on the pathology of cone dystrophy.
Adolescent ; Adult ; Child ; Child, Preschool ; Electroretinography ; Female ; Fluorescein Angiography ; Fundus Oculi ; Humans ; Male ; Middle Aged ; Ophthalmoscopy ; Reproducibility of Results ; Retinal Cone Photoreceptor Cells/*pathology ; Retinal Dystrophies/*pathology/physiopathology ; Retrospective Studies ; Tomography, Optical Coherence/*methods ; Visual Acuity ; Young Adult