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Der Ophthalmologe : Zeitschrift Der... Sep 2018The therapeutic principle of examinations of children under general anaesthesia using microscope-integrated optical coherence tomography (MI-OCT) is presented. The aim... (Review)
Review
BACKGROUND
The therapeutic principle of examinations of children under general anaesthesia using microscope-integrated optical coherence tomography (MI-OCT) is presented. The aim was to assess novel indications as well as limitations for MI-OCT to enhance ophthalmological examinations of neonates and children under general anesthesia.
METHODS
The study was based on a review of the literature from google.scholar.com and PubMed and our own data from a prospective study (Department for Ophthalmology, University of Cologne) of 14 children with anterior and posterior segment anomalies undergoing examinations under anesthesia. Patients were examined using a commercially available MI-OCT device. The study analyzed the general feasibility of MI-OCT for ophthalmological examination of children under general anesthesia for the anterior and posterior eye segments and the benefits of indications and intraoperative findings.
RESULTS
The MI-OCT significantly enriched the examinations of children under general anesthesia and delivered additional information not visible with the surgical microscope. Even in situations with a limited anterior chamber view MI-OCT enabled estimation of distances, such as corneal thickness. In addition to influencing therapeutic decisions, in 12/14 children MI-OCT also enabled examination of the thickness of the nerve fibre layer of the optic nerve disc and the retina.
CONCLUSION
The data presented here underline the benefit of the intraoperative MI-OCT in ophthalmological examinations of children under general anesthesia. In particular MI-OCT enables examinations of children with corneal opacification, if an ophthalmological examination under general anesthesia becomes necessary.
Topics: Child; Humans; Infant, Newborn; Microscopy; Optic Disk; Posterior Eye Segment; Prospective Studies; Tomography, Optical Coherence
PubMed: 29971474
DOI: 10.1007/s00347-018-0756-3 -
Arquivos Brasileiros de Oftalmologia 2020This study aimed to evaluate optic nerve head parameters and inner retinal layer thicknesses in obese children and adolescents.
PURPOSE
This study aimed to evaluate optic nerve head parameters and inner retinal layer thicknesses in obese children and adolescents.
METHODS
Forty-one eyes of 41 pediatric obese participants and 41 eyes of 41 age- and sex-matched healthy controls were included in this study. Body mass index was calculated, based on sex and age, using body weight and height measurements. Blood lipid values (i.e., cholesterol, low-density lipoprotein, high-density lipoprotein, and triglyceride) were measured in obese participants. Optical coherence tomography was used to examine optic nerve head parameters, including rim area, disc area, cup-to-disc ratio, and cup volume, as well as the thicknesses of retinal nerve fiber layers and macular ganglion cell-inner plexiform layers.
RESULTS
Optic disc parameters were similar in obese and healthy children (p>0.05). The percentage of binocular retinal nerve fiber layer thickness symmetry was significantly different between obese and control groups (p=0.003). Compared to the control group, participants in the obese group exhibited thinner retinal nerve fiber layers in the superior quadrants (p=0.04) and thinner ganglion cell-inner plexiform layers in the superior-temporal sectors (p=0.04). There were no statistically significant correlations between the ocular parameters and lipid blood test values assessed in this study (p>0.05). Body mass index was significantly negatively correlated with the mean retinal nerve fiber layer thickness (r=-0.33, p=0.03) in the obese group. There was no significant correlation between intraocular pressure and body mass index (r=0.05, p=0.74).
CONCLUSION
Compared to healthy children, obese children had greater binocular retinal nerve fiber layer thickness asymmetry and thinner retinal nerve fiber and ganglion cell-inner plexiform layers in several sectors. Blood lipid levels were not associated with retinal thickness or optic disc parameters in obese children.
Topics: Adolescent; Child; Humans; Nerve Fibers; Obesity; Optic Disk; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 33084815
DOI: 10.5935/0004-2749.20200047 -
American Journal of Ophthalmology Apr 2021To study the effects of age, sex, intraocular pressure (IOP), corneal thickness, axial length (AXL), disc area, and the signal strength of the scan on optical coherence...
PURPOSE
To study the effects of age, sex, intraocular pressure (IOP), corneal thickness, axial length (AXL), disc area, and the signal strength of the scan on optical coherence tomography (OCT) parameters of normal subjects in the L V Prasad Eye Institute-Glaucoma Epidemiological and Molecular Genetic Study (LVPEI-GLEAMS), a population-based study.
DESIGN
Cross-sectional study.
METHODS
A total of 1,100 eyes (1,100 subjects) of normal adults aged between 40 and 80 years from LVPEI-GLEAMS underwent macular and optic nerve head imaging with spectral-domain OCT (SDOCT). Effect of age, sex, IOP, central corneal thickness (CCT) and AXL, disc area, and signal strength of the OCT scan on retinal nerve fiber layer (RNFL) thickness, rim area, and ganglion cell-inner plexiform layer (GC-IPL) thickness measurements were evaluated using univariate and multivariate regression models.
RESULTS
Mean rim area, RNFL, and GC-IPL thickness were 1.31 mm (standard deviation [SD] = 0.22), 93.7 μm (SD = 9.3) and 79.6 μm (SD = 8.7), respectively. Age had a negative association with RNFL thickness (coefficient: -0.18, P < .001) and GC-IPL thickness (-0.18, P < .001). GC-IPL thickness was significantly less in women than in men (-1.05, P < .001). AXL had a negative association with rim area (-0.05, P < .001). Disc area was positively associated with RNFL thickness (4.90, P < .001) and rim area (0.15, P < .001). Signal strength of OCT scan was positively associated with RNFL thickness (1.6, P < .001) and negatively associated with rim area (-0.02, P < .001).
CONCLUSION
Age, sex, AXL, disc area, and signal strength of the scan were significantly associated with OCT measurements. These factors may need to be considered while interpreting the OCT parameters in pathologic conditions such as glaucoma.
Topics: Adult; Age Factors; Aged; Aged, 80 and over; Axial Length, Eye; Cornea; Cross-Sectional Studies; Female; Healthy Volunteers; Humans; Intraocular Pressure; Male; Middle Aged; Nerve Fibers; Optic Disk; Retinal Ganglion Cells; Sex Factors; Tomography, Optical Coherence
PubMed: 33307000
DOI: 10.1016/j.ajo.2020.11.015 -
Acta Ophthalmologica Sep 2022To map the morphology of the retina and optic disc in adolescents with surgically treated hydrocephalus (HC) in infancy and to compare the results with healthy controls.
PURPOSE
To map the morphology of the retina and optic disc in adolescents with surgically treated hydrocephalus (HC) in infancy and to compare the results with healthy controls.
METHODS
The study comprised 26 adolescents (16 male, mean age 15 years) with HC and 31 sex- and aged-matched controls. The following optical coherence tomography (OCT) parameters were obtained: macular retinal thickness (MRT) and volume (MRV), thickness of the macular and peripapillary retinal nerve fibre layer (ppRNFL), and area of the optic disc, cup and rim.
RESULTS
The MRT was thinner amongst those with HC compared with controls (right eye (RE) 262.2 ± 15.3 and 275.8 ± 15.1 μm; p = 0.0051), and the MRV was smaller (RE 7.37 ± 0.36 and 7.83 ± 0.35 mm ; p = 0.0002). The HC group showed a thinner ppRNFL (RE 88.3 ± 14.9 and 103.5 ± 8.1 μm; p = 0.0002) but a thicker central macular RNFL (RE 11.6 ± 10.4 and 2.07 ± 3.00 μm; p = <0.0001) and foveal minimum (RE 211.1 ± 32.0 and 186.3 ± 15.9 μm; p = 0.0013). Optic disc variables showed no difference between groups. Correlations were found in the HC group between best corrected visual acuity (expressed in logMAR) and ppRNFL (RE r = -0.56, p = 0.018), and disc area (RE r = -0.52, p = 0.033).
CONCLUSION
Thinner ppRNFL and MRT and smaller MRV were found in adolescents with surgically treated HC in infancy compared with controls. In contrast, the central macular RNFL and foveal minimum were thicker. Further studies are required to evaluate the diagnostic value of OCT to indicate increased intracranial pressure timely and follow-up in individuals with surgically treated HC.
Topics: Adolescent; Aged; Humans; Hydrocephalus; Male; Nerve Fibers; Optic Disk; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35507694
DOI: 10.1111/aos.15162 -
Computers in Biology and Medicine Jul 2022Anterior segment optical coherence tomography (AS-OCT) constitutes an important imaging modality to examine the anterior eye, which is commonly used in research and... (Review)
Review
BACKGROUND
Anterior segment optical coherence tomography (AS-OCT) constitutes an important imaging modality to examine the anterior eye, which is commonly used in research and clinical practice. Since its introduction, a range of image analysis methods have been developed to quantify these images using different analysis techniques for various applications. This systematic review aims to provide an in-depth summary and to classify image analysis techniques found in the literature applied to AS-OCT images.
METHODS
Scopus and Engineering Village databases were searched to retrieve relevant studies up to and including January 2022. Customized search statements were used along with cross reference and hand search techniques to ensure a complete coverage. Performance metrics were extracted, analyzed, and compared (when possible).
RESULTS
Three main application categories were identified: glaucoma assessment, corneal segmentation, and anterior segment biometry. These three categories constitute 66% of the total studies reported in this review. Studies were also analyzed by year of publication, and since 2019 deep learning methods were favored over traditional programming or machine learning methodologies. Overall, the AS-OCT image analysis field is less developed compared to posterior segment OCT imaging.
CONCLUSION
This review presents the state of the art in the field of AS-OCT image analysis. It highlights the opportunities for future areas of research, such as the expansion of DL methods and the extension to specific clinical areas that have received limited attention including surgical monitoring, contact lenses, and specific clinical conditions such as keratoconus and corneal lesions.
Topics: Anterior Eye Segment; Biometry; Cornea; Humans; Keratoconus; Tomography, Optical Coherence
PubMed: 35533455
DOI: 10.1016/j.compbiomed.2022.105471 -
Indian Journal of Ophthalmology Feb 2021The objective of this study was to identify the diagnostic features of optic nerve head melanocytoma (ONH-MCT) on spectral domain optical coherence tomography (SD OCT)...
PURPOSE
The objective of this study was to identify the diagnostic features of optic nerve head melanocytoma (ONH-MCT) on spectral domain optical coherence tomography (SD OCT) and OCT angiography (OCT-A).
METHODS
Retrospective study of 11 patients for their demographic, clinical features and imaging including SD OCT (tumour location, extent and interface) and OCT-A (surface and intrinsic vascularity) were reviewed. Flow rate percentage (FR %) was calculated over the lesion and compared to fellow eye and similar pigmented lesions.
RESULTS
The average age was 52.8 ± 10.9 years. ONH-MCT tumors occupied 3-tissue spaces- optic disc (n = 2), retinal layer (n = 5) and retina-choroidal layers (n = 4). SD OCT (11 eyes) showed elevated hyper reflective disorganized retinal layers with posterior shadowing (9 eyes) and hyper reflective dots within the tumor (all eyes). Microvascular features on OCT-A (8 eyes) in radial peripapillary capillary slab showed surface vascularization (7 eyes) and intrinsic vascularity in choroidal slab (8 eyes) with surrounding hypo reflective boundary. The mean FR % was higher at 65.1 ± 3.77% (CI: 61.9-68.2) compared to mean FR at 60.4 ± 1.06% (CI: 59.5-61.2) in the fellow eye (p = 0.01). Comparison with nevus and melanoma SD OCT showed a high reflective choroidal layer with normal or irregular outer retinal layers respectively; OCT-A showed hypo reflective area at the center with hyper reflective boundary and iso reflective area at center with hyper reflective boundary respectively.
CONCLUSION
SD OCT and OCT-A features may help to differentiate ONH-MCT from clinically similar looking pigmented lesions like nevus and melanoma.
Topics: Adult; Choroid; Humans; Middle Aged; Optic Disk; Retrospective Studies; Skin Neoplasms; Tomography, Optical Coherence
PubMed: 33463586
DOI: 10.4103/ijo.IJO_710_20 -
Interocular symmetry of optical coherence tomography parameters in healthy children and adolescents.Scientific Reports Jan 2022Evaluation of interocular asymmetry of optical coherence tomography (OCT) parameters is important for the glaucoma and optic neuropathies. This study was performed to...
Evaluation of interocular asymmetry of optical coherence tomography (OCT) parameters is important for the glaucoma and optic neuropathies. This study was performed to evaluate the interocular asymmetry of OCT parameters in healthy children and adolescents. The circumpapillary retinal nerve fiber layer (RNFL) thickness, optic nerve head (ONH) parameters, and macular ganglion cell-inner plexiform layer (GCIPL) thickness were measured in 620 eyes of 310 healthy children and adolescents using Cirrus HD-OCT. The interocular asymmetry (right eye-left eye) in the OCT parameters was analyzed. The mean ± standard deviation age was 10.3 ± 3.7 years (range 5-17). The right eyes showed thinner superior quadrant RNFL, thicker nasal and temporal quadrant RNFL, lesser rim and disc areas, and thinner average, superior, and superonasal GCIPL than the left eyes (P < 0.05). The 2.5th and 97.5th percentile interocular difference tolerance limits were - 9.0 μm and 11.0 μm for average RNFL thickness, - 0.21 and 0.18 for average cup-to-disc ratio, and - 4.0 μm and 4.0 μm for average GCIPL thickness, respectively. Interocular differences were found in RNFL thickness, ONH parameters, and GCIPL thickness in healthy children and adolescents. These findings should be considered when comparing OCT parameters between the right and left eyes.
Topics: Adolescent; Child; Child, Preschool; Female; Glaucoma; Healthy Volunteers; Humans; Male; Nerve Fibers; Optic Disk; Optic Nerve Diseases; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35027614
DOI: 10.1038/s41598-021-04563-3 -
Journal of Biomedical Optics Dec 2021Light-field fundus photography has the potential to be a new milestone in ophthalmology. Up-to-date publications show only unsatisfactory image quality, preventing the...
SIGNIFICANCE
Light-field fundus photography has the potential to be a new milestone in ophthalmology. Up-to-date publications show only unsatisfactory image quality, preventing the use of depth measurements. We show that good image quality and, consequently, reliable depth measurements are possible, and we investigate the current challenges of this novel technology.
AIM
We investigated whether light field (LF) imaging of the retina provides depth information, on which structures the depth is estimated, which illumination wavelength should be used, whether deeper layers are measurable, and what kinds of artifacts occur.
APPROACH
The technical setup, a mydriatic fundus camera with an LF imager, and depth estimation were validated by an eye model and in vivo measurements of three healthy subjects and three subjects with suspected glaucoma. Comparisons between subjects and the corresponding optical coherence tomography (OCT) measurements were used for verification of the depth estimation.
RESULTS
This LF setup allowed for three-dimensional one-shot imaging and depth estimation of the optic disc with green light. In addition, a linear relationship was found between the depth estimates of the OCT and those of the setup developed here. This result is supported by the eye model study. Deeper layers were not measurable.
CONCLUSIONS
If image artifacts can be handled, LF technology has the potential to help diagnose and monitor glaucoma risk at an early stage through a rapid, cost-effective one-shot technology.
Topics: Fluorescein Angiography; Humans; Optic Disk; Retina; Technology; Tomography, Optical Coherence
PubMed: 34921542
DOI: 10.1117/1.JBO.26.12.126002 -
IEEE Transactions on Medical Imaging Jun 2021Recently, automatic diagnostic approaches have been widely used to classify ocular diseases. Most of these approaches are based on a single imaging modality (e.g.,...
Recently, automatic diagnostic approaches have been widely used to classify ocular diseases. Most of these approaches are based on a single imaging modality (e.g., fundus photography or optical coherence tomography (OCT)), which usually only reflect the oculopathy to a certain extent, and neglect the modality-specific information among different imaging modalities. This paper proposes a novel modality-specific attention network (MSAN) for multi-modal retinal image classification, which can effectively utilize the modality-specific diagnostic features from fundus and OCT images. The MSAN comprises two attention modules to extract the modality-specific features from fundus and OCT images, respectively. Specifically, for the fundus image, ophthalmologists need to observe local and global pathologies at multiple scales (e.g., from microaneurysms at the micrometer level, optic disc at millimeter level to blood vessels through the whole eye). Therefore, we propose a multi-scale attention module to extract both the local and global features from fundus images. Moreover, large background regions exist in the OCT image, which is meaningless for diagnosis. Thus, a region-guided attention module is proposed to encode the retinal layer-related features and ignore the background in OCT images. Finally, we fuse the modality-specific features to form a multi-modal feature and train the multi-modal retinal image classification network. The fusion of modality-specific features allows the model to combine the advantages of fundus and OCT modality for a more accurate diagnosis. Experimental results on a clinically acquired multi-modal retinal image (fundus and OCT) dataset demonstrate that our MSAN outperforms other well-known single-modal and multi-modal retinal image classification methods.
Topics: Diagnostic Techniques, Ophthalmological; Fundus Oculi; Optic Disk; Retina; Tomography, Optical Coherence
PubMed: 33625978
DOI: 10.1109/TMI.2021.3059956 -
Ophthalmic Research 2022The main aim of this article was to study the retinal peripapillary and macular vascular structures in eyes with primary angle-closure suspects (PACS) using optical...
INTRODUCTION
The main aim of this article was to study the retinal peripapillary and macular vascular structures in eyes with primary angle-closure suspects (PACS) using optical coherence tomography angiography (OCTA).
METHODS
In this cross-sectional study, control and PACS subjects were recruited from a community screening. Only one eye per subject was used for analysis. All participants underwent a questionnaire survey, physical and ophthalmic examinations, ocular biometry measurements, and OCTA. We compared basic demographics and vessel structure parameters between control and PACS eyes. Univariate and multivariate linear regression analyses were performed to investigate factors associated with vascular parameters in both groups.
RESULTS
Data from 254 subjects including 155 PACS and 99 controls were analyzed. In the peripapillary region, PACS eyes showed similar retina nerve fiber layer (RNFL) and vessel densities (VDs) including and excluding large vessels compared to control eyes. Compared to control eyes, all macular OCTA parameters showed significant differences in PACS eyes, including decreased superficial VD (p = 0.006) and deep VD (p = 0.004), larger fovea avascular zone (FAZ) area (p = 0.006), and longer FAZ perimeter (p = 0.004). Gender (p = 0.039), age (p < 0.001), and Garway-Heath superior hemisphere RNFL (p < 0.001) were risk factors influencing optic disc VD excluding large vessels. Axial length was the major factor affecting macula superficial and deep VDs (p = 0.004 and 0.001 respectively), while PACS was an independent factor associated with larger FAZ perimeter (p = 0.046).
CONCLUSION
While PACS and control eyes have comparable RNFL and vascular structure around the optic nerve head, macular vascular structures are significantly different.
Topics: Humans; Cross-Sectional Studies; Macula Lutea; Optic Disk; Retinal Vessels; Tomography, Optical Coherence; Angiography
PubMed: 34649251
DOI: 10.1159/000520030