Preserved functional and structural integrity of the papillomacular area correlates with better visual acuity in retinitis pigmentosa

Abstract

PurposeLinking multifocal electroretinography (mfERG) and optical coherence tomography (OCT) findings with visual acuity in retinitis pigmentosa (RP) patients.DesignProspective, cross-sectional, nonintervention study.SubjectsPatients with typical RP and age-matched controls, who underwent SD-OCT (spectral domain OCT) and mfERG, were included.MethodsMfERG responses were averaged in three zones (zone 1 (0°-3°), zone 2 (3°-8°), and zone 3 (8°-15°)). Baseline-to-trough- (N1) and trough-to-peak amplitudes (N1P1) of the mfERG were compared with corresponding areas of the OCT. The papillomacular area (PMA) was analyzed separately. Correlations between best-corrected visual acuity (BCVA, logMAR) and each parameter were determined.Main outcome measuresComparing structural (OCT) and functional (mfERG) measures with the BCVA.ResultsIn RP patients, the N1 and N1P1 responses showed positive association with the central retinal thickness outside zone 1 (P≤0.002), while the central N1 and the N1P1 responses in zones 1, 2, and 3-with the BCVA (P≤0.007). The integrity of the IS/OS line on OCT showed also a positive association with the BCVA (P<0.001). Isolated analysis of the PMA strengthened further the structure-function association with the BCVA (P≤0.037). Interactions between the BCVA and the OCT, respectively, the mfERG parameters were more pronounced in the RP subgroup without macular edema (P≤0.020).ConclusionIn RP patients, preserved structure-function of PMA, measured by mfERG amplitude and OCT retinal thickness, correlated well with the remaining BCVA. The subgroup analyses revealed stronger links between the examined parameters, in the RP subgroup without appearance of macular edema.

Metabolic, structural and functional alterations in patients with inherited diseases of the retina

“…Within the RP group we documented also the link between the functional and structural integrity and the preserved visual acuity. Here, the correlations found were more pronounced in the RP subgroup without clinical appearance of macular oedema (Konieczka et al 2016a). Furthermore, we found, that the presence of macular oedema in RP patients correlates with altered metabolic function.…”

“…Exclusion criteria for patients and controls were as follows: the above mentioned inclusion criteria not fulfilled, the presence of ocular and/or systemic pathology other than IRD (for instance diabetes mellitus, hypertension or other metabolic and neurodegenerative diseases, potentially affecting the vessel diameter and the SO 2 measurements), unstable fixation and RO images with inadequate quality. Materials and methods (described in details: T€ urksever et al 2014b;T€ urksever et al 2015b;Lopez Torres et al 2015;Konieczka et al 2016a;Todorova et al 2016;Bojinova et al 2017) Retinal vessel oximetry imaging…”

“…Relationship between the structural and the functional integrity of the central retina and visual acuity in RP patients (Konieczka et al 2016a) With the outer retinal degeneration progression, only a central island of functioning receptors remains, at which stage the RP patient is left with tunnel vision (Ammann et al 1965;Hamel 2006;Hartong et al 2006). The macula and the papillomacular bundle (PMB) are the points of great interest in RP patients, first due to their importance for assessing the remaining visual function, and second, because of their particular anatomical structure and role.…”

“…6 To evaluate the relationship between the structural and functional integrity of the central/papillomacular area and the residual visual acuity in RP (Konieczka et al 2016a).…”

Higher retinal vessel oxygen saturation: investigating its relationship with macular oedema in retinitis pigmentosa patients

“…For instance, the integrity of the photoreceptor inner/outer segment junction, labelled as IS/OS line on OCT imaging, has been strongly associated with better visual function and higher retinal sensitivity [24][25][26]. The correlations between the best corrected visual acuity and the structure-function parameters were noticeably more pronounced within the RP subgroup without clinical appearance of macular oedema (no-ME-RP, retinitis pigmentosa subgroup without macular oedema) [27]. Surprisingly, the RP subgroup with clinical appearance of macular oedema (ME-RP, retinitis pigmentosa subgroup with macular oedema), even with better preservation of the central vision, showed more advanced stage of photoreceptor degeneration with greater disruption of the IS/OS line, and greater attenuation of the central mfERG responses.…”