Differences in Optical Coherence Tomography Assessment of Bruch Membrane Opening Compared to Stereoscopic Photography for Estimating Cup-to-Disc Ratio

BRAIN AND EYE AS POTENTIAL TARGETS FOR IONIZING RADIATION IMPACT. PART III / FEATURES MORPHOMETRIC RETINAL PARAMETERS, AMPLITUDE AND LATENCY COMPONENTS OF VISUAL EVOKED POTENTIAL IN RADIATION EXPOSED IN UTERO

One of the current problems of modern radiobiology is determine the characteristics of the manifestation of radiation-induced effects not only at different dose loads, but also at different stages of development of the organism. In previous reports, we have summarized available evidence that at certain ages there is a comparative acceleration of radiation-induced pathological changes in the eye and brain, and the study and assessment of the risk of possible ophthalmic and neurological pathology in remote periods after contamination of radioactive areas. Data of irradiated in utero individuals are possible on the basis of observation of the state of the visual analyzer in persons who underwent intrauterine irradiation in 1986. Therefore, a parallel study of retinal morphometric parameters, amplitude and latency of components of evoked visual potentials in irradiated in utero individuals was performed.

OBJECTIVE

to evaluate the retinal morphometric parameters, amplitude and latency components of the evoked visual potentials in intrauterine irradiated persons.

MATERIALS AND METHODS

The results of surveys of 16 people irradiated in utero in the aftermath of the Chornobyl disaster were used; the comparison group were residents of Kyiv of the corresponding age (25 people). Optical coherence tomography was performed on a Cirrus HD-OCT, Macular Cube 512x128 study technique was used. At the same time, the study of visual evoked potentials on the inverted pattern was performed, and occipital leads wereanalyzed. Visual evoked potentials were recorded on a reversible chess pattern (VEP) - an electrophysiological test, which is a visual response to a sharp change in image contrast when presenting a reversible image of a chessboard.

RESULTS

In those irradiated in utero at the age of 22-25 years, there was a probable increase in retinal thickness in the fovea, there was a tendency to increase the thickness of the retina in the areas around the fovea. When recording visual evoked potentials on a reversible chess pattern in this group, there was a tendency to decrease the amplitudes of components (N75, P100, N145, P200) in the right and left parieto-occipital areas and asymmetric changes in latency of these components.

CONCLUSIONS

Early changes of fovea recorded in OCT and decreasing amplitudes of components of visual evoked potentials on the reversible chess pattern at the age of 22 25 years may indicate a risk of development in patients irradiated in utero, early age-related macular degeneration, as well as increased risk and increased risk structures of the visual analyzer.

The agreement between optical coherence tomography angiography and non-mydriatic retinal camera in estimating the optic nerve head parameters and relations with the peripapillary vessel density in primary open-angle glaucoma

BACKGROUND/OBJECTIVES

To investigate the agreement between optical coherence tomography angiography (OCT-A) and non-mydriatic retinal camera (NMRC) in estimating the optic nerve head (ONH) parameters and evaluate the associations between peripapillary vessel density (VD) with ONH parameters assessed by both devices.

METHODS

The OCT-A and NMRC images of 262 participants (138 eyes were diagnosed with POAG, 63 were glaucoma suspect, and 61 were healthy subjects) were screened retrospectively. The vertical cup-to-disc ratio (VCDR), cup-to-disc area ratio (CDAR), rim area (RA), disc area (DA), and cup volume (CV) were recorded using both devices. Peripapillary VD data were also recorded using OCT-A. The intraclass correlation coefficient (ICC) and Bland-Altman plots were obtained to investigate the agreement between the devices. Age- and intraocular pressure (IOP)-corrected associations between the VD and ONH parameters measured by the two devices were analyzed using linear regression models.

RESULTS

ICC revealed excellent agreement for VCDR and CDAR, but poor agreement for RA, DA, and CV (ICC = 0.801, 0.793, 0.445, 0.298, and 0.527, respectively). The Bland-Altman plots showed poor agreement for VCDR and CDAR with a large span of limits of agreement (0.500 and 0.528, respectively) and significant proportional biases (P < 0.05). VD was found to be strongly associated with the VCDR and CDAR measurements of both devices (P < 0.001), but the associations were stronger for the measurements of NMRC.

CONCLUSIONS

The disagreement between the devices should be considered in clinical practice. The associations between the VD and ONH parameters proved once again the importance of the ONH parameters in terms of the management of glaucoma patients.

MORPHOMETRIC PARAMETERS OF RETINAL MACULAR ZONE IN RECONVALESCENTS OF ACUTE RADIATION SICKNESS (IN REMOTE PERIOD)

OBJECTIVE

evaluate the retinal morphometric parameters of the reconvalescents in remote period after acute radi-ation sickness.

MATERIALS AND METHODS

A complete ophthalmologic examination was carried out on 7 reconvalescents of acuteradiation sickness. The examined are divided into two subgroups: 1) patients with macular degeneration of the reti-na (8 eyes); 2) patients without clinical signs of macular pathology (6 eyes). Parameters of the retina in the cen-tral retina zone studied using the method of optical coherence tomography. To evaluate the results of surveys usedstatistical methods: average values of quantitative indicators calculation, estimation of probability difference byStudent's method.

RESULTS

Optical coherence tomography revealed a statistically significant increase of the thickness of the retina inthe fovea in all reconvalescents of acute radiation sickness.

CONCLUSIONS

It was shown that the thickness of the retina in the fovea and paramacular zone in persons who suf-fered acute radiation sickness is significantly higher than in the control. These changes observed in all reconvalis-cents ARS - both in person with sings of macular degeneration, and in those whose clinical manifestations were notdetected. The presence of a correlation between the volume of the retina in the macular zone and the documentedradiation dose of the study group emphasizes the perspectives of next OCT examination of the retina of reconvales-cents of ARS to study the mechanism of retina's damage in this category of victims of the Chornobyl accident.

Glaucoma Specialist Detection of Optical Coherence Tomography Suspicious Rim Tissue in Glaucoma and Glaucoma Suspect Eyes

PURPOSE

To assess glaucoma specialists' detection of optic nerve head (ONH) rim tissue that is thin by optical coherence tomography (OCT) criteria.

DESIGN

Reliability analysis.

METHODS

Five clinicians marked the disc margin (DM) and rim margin (RM) on stereophotographs of 151 glaucoma or glaucoma suspect eyes obtained within 3 months of OCT imaging. The photo and OCT infrared image for each eye were co-localized and regionalized into 12 sectors relative to the axis between the Bruch membrane opening (BMO) centroid and the fovea. For each clinician, the distance from BMO centroid to their DM (DM radius) and RM (RM radius) was used to generate sectoral rim width (RW) (DM radius-RM radius) and cup-to-disc ratio (CDR) (RM radius/DM radius) estimates. OCT minimum rim width (MRW) was determined by sector. Among all eyes, for each OCT MRW suspicious sector (<5% of OCT normative database), we determined each clinician's detection (clinician CDR ≥ 0.7).

RESULTS

Clinicians most commonly failed to detect OCT suspicious rim tissue in the nasal sectors. Among 502 sectors with suspicious OCT MRW, all 5 clinicians rated CDR ≥ 0.7 in only 29.5% and all 5 clinicians rated CDR < 0.7 in 21%. OCT suspicious rim thickness was most common (32% of eyes) in the nasal and inferior sectors. MRW vs clinician RW discordance was greatest nasally, while BMO vs clinician DM discordance was greatest temporally.

CONCLUSIONS

Clinicians most commonly failed to detect OCT suspicious rim thickness nasally where suspicious rim tissues were also most common.