scholarly journals Optical Coherence TomographyStudy of peripapillary Nerve Fiber layer ThicknessinThyroid Associated Ophthalmopathy

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
Z I R Elkady ◽  
S Elwan ◽  
A M A Said ◽  
Y A T Farweez ◽  
M M M Mahdy
Keyword(s):  
Optic Nerve ◽  
Visual Field ◽  
Nerve Fiber ◽  
Severity Score ◽  
University Hospital ◽  
Visual Field Defects ◽  
Optical Coherence ◽  
Fiber Layer ◽  
Nerve Fiber Layer ◽  
Severity Of The Disease

Abstract Background Thyroid Associated Ophthalmopathy (TAO) or Graves Opthalmopathy (GO) is a very common autoimmune disorder of the thyroid gland which activates the gland function and result in hyperthyroidism. Some patients with graves disease(GD) develop localized manifestations including GO and dermopathy. Dysthyroid optic neuropathy (DON) is impairment of optic nerve function due to GO, the most serious complication of GO which occurs in about 4–8% of patients, it occurs due to ischemia and inflammation of the optic nerve, also compression of the optic nerve due to enlargement of extraocular muscles at the apex of orbit. Objective To assess peripapillary retinal nerve fiber layer (pRNFL) thickness in GD and to correlate it with the severity of the disease. Patients and Methods This study was conducted on 40 eyes of 21 recently diagnosed GO patients (two patients were single eyed) recruited from Endocrinology clinic and examined at Ophthalmology clinic, Ain Shams University Hospital in the period from March 2018 to September 2018. Complete ophthalmologic examination, proptosis assessment of direction and degree, Visual Field (VF) examination, clinical activity score (CAS), severity score assessment and Optical Coherence Tomography (OCT) were performed to all patients . Results In the whole group of patients; the mean average pRNFL was 109.53 um ± 12.33 SD (range: 86 – 140), median MD was -4.53 (range:-0.66 to-18.95) and -8.04 ± -2.15 SD, mean PSD was 5.55 ± 3.8 SD (range: 1.11 to 12.73). Normal average pRNFL thickness (according to normative data base included in the OCT program) was found in 15 eyes (37.5%) and those had abnormal increase in thickness was 12 eyes (30%). Abnormal decrease in thickness was detected in 13 eyes (32.5%). Conclusion PRNFL thickness abnormalities were detected in 25 eyes (62%) of recently diagnosed GO patients. This might be associated with localized visual field defects. Regular follow up of intra ocular pressure (IOP), serial VF examinations, are required to decide further management of those patients, as OCT results were correlated with degree of eye protrusion and the severity of the disease (CAS and severity score).

Automated Perimetry in Glaucoma

Visual Fields ◽  
2010 ◽  
Author(s):  
Hylton R. Mayer ◽  
Marc L. Weitzman
Keyword(s):  
Optic Nerve ◽  
Visual Field ◽  
Nerve Fiber ◽  
Optic Disc ◽  
Structural Damage ◽  
Visual Field Defects ◽  
Fiber Layer ◽  
Glaucomatous Damage ◽  
Retinal Fibers ◽  
Field Defects

Clinical experience and multiple prospective studies, such as the Collaborative Normal Tension Glaucoma Study and the Los Angeles Latino Eye Study, have demonstrated that the diagnosis of glaucoma is more complex than identifying elevated intraocular pressure. As a result, increased emphasis has been placed on measurements of the structural and functional abnormalities caused by glaucoma. The refinement and adoption of imaging technologies assist the clinician in the detection of glaucomatous damage and, increasingly, in identifying the progression of structural damage. Because visual field defects in glaucoma patients occur in patterns that correspond to the anatomy of the nerve fiber layer of the retina and its projections to the optic nerve, visual functional tests become a link between structural damage and functional vision loss. The identification of glaucomatous damage and management of glaucoma require appropriate, sequential measurements and interpretation of the visual field. Glaucomatous visual field defects usually are of the nerve fiber bundle type, corresponding to the anatomic arrangement of the retinal nerve fiber layer. It is helpful to consider the division of the nasal and temporal retina as the fovea, not the optic nerve head, because this is the location that determines the center of the visual field. The ganglion cell axon bundles that emanate from the nasal side of the retina generally approach the optic nerve head in a radial fashion. The majority of these fibers enter the nasal half of the optic disc, but fibers that represent the nasal half of the macula form the papillomacular bundle to enter the temporal-most aspect of the optic nerve. In contrast, the temporal retinal fibers, with respect to fixation, arc around the macula to enter the superotemporal and inferotemporal portions of the optic disc. The origin of these arcuate temporal retinal fibers strictly respects the horizontal retinal raphe, temporal to the fovea. As a consequence of this superior-inferior segregation of the temporal retinal fibers, lesions that affect the superotemporal and inferotemporal poles of the optic disc, such as glaucoma, tend to cause arcuateshaped visual field defects extending from the blind spot toward the nasal horizontal meridian.

scholarly journals Estimating Visual Field Mean Deviation using Optical Coherence Tomographic Nerve Fiber Layer Measurements in Glaucoma Patients

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ou Tan ◽  
David S. Greenfield ◽  
Brian A. Francis ◽  
Rohit Varma ◽  
Joel S. Schuman ◽  
...  
Keyword(s):  
Visual Field ◽  
Nerve Fiber ◽  
Weighted Averaging ◽  
Mean Deviation ◽  
Optical Coherence ◽  
Fiber Layer ◽  
Nerve Fiber Layer ◽  
Maximal Correlation ◽  
Advanced Stages ◽  
Higher Sensitivity

AbstractTo construct an optical coherence tomography (OCT) nerve fiber layer (NFL) parameter that has maximal correlation and agreement with visual field (VF) mean deviation (MD). The NFL_MD parameter in dB scale was calculated from the peripapillary NFL thickness profile nonlinear transformation and VF area-weighted averaging. From the Advanced Imaging for Glaucoma study, 245 normal, 420 pre-perimetric glaucoma (PPG), and 289 perimetric glaucoma (PG) eyes were selected. NFL_MD had significantly higher correlation (Pearson R: 0.68 vs 0.55, p < 0.001) with VF_MD than the overall NFL thickness. NFL_MD also had significantly higher sensitivity in detecting PPG (0.14 vs 0.08) and PG (0.60 vs 0.43) at the 99% specificity level. NFL_MD had better reproducibility than VF_MD (0.35 vs 0.69 dB, p < 0.001). The differences between NFL_MD and VF_MD were −0.34 ± 1.71 dB, −0.01 ± 2.08 dB and 3.54 ± 3.18 dB and 7.17 ± 2.68 dB for PPG, early PG, moderate PG, and severe PG subgroups, respectively. In summary, OCT-based NFL_MD has better correlation with VF_MD and greater diagnostic sensitivity than the average NFL thickness. It has better reproducibility than VF_MD, which may be advantageous in detecting progression. It agrees well with VF_MD in early glaucoma but underestimates damage in moderate~advanced stages.

Precision of Optic Nerve Head and Retinal Nerve Fiber Layer Parameter Measurements by Spectral-domain Optical Coherence Tomography

2018 ◽  
Vol 27 (5) ◽  
pp. 407-414 ◽  
Author(s):  
Laura M. Schrems-Hoesl ◽  
Wolfgang A. Schrems ◽  
Robert Laemmer ◽  
Friedrich E. Kruse ◽  
Christian Y. Mardin
Keyword(s):  
Optical Coherence Tomography ◽  
Optic Nerve ◽  
Nerve Fiber ◽  
Retinal Nerve Fiber Layer ◽  
Optic Nerve Head ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Fiber Layer ◽  
Nerve Fiber Layer ◽  
Layer Parameter
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