Julio J. González-López

OCT: New perspectives in neuro-ophthalmology

Optical coherence tomography (OCT) has become essential to evaluate axonal/neuronal integrity, to assess disease progression in the afferent visual pathway and to predict visual recovery after surgery in compressive optic neuropathies. Besides that OCT testing is considered a powerful biomarker of neurodegeneration and a promising outcome measure for neuroprotective trials in multiple sclerosis (MS). Currently, spectral-domain OCT (SD-OCT) technology allows quantification of retinal individual layers. The Ganglion Cell layer (GCL) investigation has become one of the most useful tools from a neuro-ophthalmic perspective. It has a high correlation with perimetry, is predictive of future progression and is a highly sensitive, specific of several neuro-ophthalmic pathologies. Moreover the superior correlation with clinical measures compared to peripapillary retinal nerve fiber layer (pRNFL) suggests that GCL analysis might be a better approach to examine MS neurodegeneration. In disorders with optic disk edema, such as ischemic optic neuropathy, papillitis and papilledema, reduction in RNFL thickness caused by axonal atrophy is difficult to distinguish from a swelling resolution. In this setting, and in buried optic nerve head drusen (ONHD), GCL analysis may provide more accurate information than RNFL analysis and it might be an early structural indicator of irreversible neuronal loss. Enhanced depth imaging OCT (EDI-OCT) provides in vivo detail of ONHD, allowing to evaluate and quantify the drusen dimensions. OCT is improving our knowledge in hereditary optic neuropathies. Furthermore, there is growing evidence about the role of OCT as an adjunctive biomarker of disorders such as Alzheimer and Parkinsons disease.

Comparative Diagnostic Accuracy of Ganglion Cell-Inner Plexiform and Retinal Nerve Fiber Layer Thickness Measures by Cirrus and Spectralis Optical Coherence Tomography in Relapsing-Remitting Multiple Sclerosis

Objective. To estimate sensitivity and specificity of several optical coherence tomography (OCT) measurements for detecting retinal thickness changes in patients with relapsing-remitting multiple sclerosis (RRMS), such as macular ganglion cell-inner plexiform layer (GCIPL) thickness measured with Cirrus (OCT) and peripapillary retinal nerve fiber layer (pRNFL) thickness measured with Cirrus and Spectralis OCT. Methods. Seventy patients (140 eyes) with RRMS and seventy matched healthy subjects underwent pRNFL and GCIPL thickness analysis using Cirrus OCT and pRNFL using Spectralis OCT. A prospective, cross-sectional evaluation of sensitivities and specificities was performed using latent class analysis due to the absence of a gold standard. Results. GCIPL measures had higher sensitivity and specificity than temporal pRNFL measures obtained with both OCT devices. Average GCIPL thickness was significantly more sensitive than temporal pRNFL by Cirrus (96.34% versus 58.41%) and minimum GCIPL thickness was significantly more sensitive than temporal pRNFL by Spectralis (96.41% versus 69.69%). Generalised estimating equation analysis revealed that age (P = 0.030), optic neuritis antecedent (P = 0.001), and disease duration (P = 0.002) were significantly associated with abnormal results in average GCIPL thickness. Conclusion. Average and minimum GCIPL measurements had significantly better sensitivity to detect retinal thickness changes in RRMS than temporal pRNFL thickness measured by Cirrus and Spectralis OCT, respectively.

Papillomacular Bundle and Inner Retinal Thicknesses Correlate With Visual Acuity in Nonarteritic Anterior Ischemic Optic Neuropathy

PURPOSE To evaluate the ability of the papillomacular bundle (PMB) retinal nerve fiber layer and macular inner retinal layer thickness measurements with Spectralis optical coherence tomography (OCT) to differentiate eyes with nonarteritic anterior ischemic optic neuropathy (NAION) from uninvolved eyes and to evaluate whether their thicknesses correlate with visual acuity. METHODS An observational, cross-sectional study was performed, including 29 eyes with NAION and 29 uninvolved eyes from 29 patients. Eyes underwent scanning with Cirrus OCT (peripapillary and macular scanning) and Spectralis OCT (N-site axonal peripapillary scan and a new automated segmentation macular scan to measure individual retinal layers) in both eyes. RESULTS The NAION eyes showed significant thinning versus uninvolved eyes in the macular retinal nerve fiber (P < 0.05), ganglion cell layer (GCL; P < 0.001), and inner plexiform layer (IPL; P < 0.01) by Spectralis and in the GCL-IPL by Cirrus (P < 0.02). Average and sectors of peripapillary retinal nerve fiber layer (pRNFL) and total macular thickness (TMT) were significantly reduced in NAION eyes, with both Spectralis and Cirrus OCT (P < 0.05). Spectralis temporal (ρSpearman = -0.768; P < 0.001) and PMB pRNFL thicknesses (ρSpearman = -0.675; P < 0.001), as well as central macular IPL thickness (ρSpearman = -0.735; P < 0.001), correlated strongly with best corrected visual acuity (BCVA). Quadratic regression using outer nasal TMT by Cirrus OCT and temporal pRNFL thickness by Spectralis were the best models to predict BCVA. CONCLUSIONS Macular segmentation by Spectralis and Cirrus OCT revealed inner retinal layer atrophy in NAION eyes. The temporal and PMB pRNFL thicknesses and central macular IPL thickness by Spectralis-OCT and outer nasal TMT by Cirrus were strongly correlated with BCVA in NAION eyes.

Color-Code Agreement Among Stratus, Cirrus, and Spectralis Optical Coherence Tomography in Relapsing-Remitting Multiple Sclerosis With and Without Prior Optic Neuritis

PURPOSE To evaluate the agreement of retinal nerve fiber layer (RNFL) color codes among Stratus, Cirrus, and Spectralis optical coherence tomography (OCT) in patients with relapsing-remitting multiple sclerosis. DESIGN Prospective cohort study. METHODS In 140 eyes from 70 patients having relapsing-remitting multiple sclerosis from January 2011 to September 2011, peripapillary RNFL thickness was measured using the fast RNFL program by Stratus, the optic disc cube protocol by Cirrus, and the N-site axonal analysis by Spectralis. RESULTS Overall, a moderate to good RNFL color code agreement was found (0.435-0.884), except for the nasal quadrant. The temporal quadrant was the most abnormal color coding by both Cirrus (64.7%) and Spectralis (61.7%) in both the optic neuritis (ON) and non-ON group and by Stratus (58.8%) in the ON group. Abnormal temporal RNFL color-code rate was significantly higher in ON eyes than non-ON eyes by Cirrus (P < .001), Stratus (P < .001), and Spectralis (P = .030). Overall, Cirrus significantly displayed abnormal findings while both Stratus and Spectralis displayed normal results for the inferior quadrant (P < .05). On the other hand, Spectralis OCT showed a significantly higher rate of abnormal findings while Cirrus displayed normal results for the temporal quadrant in non-ON eyes (P < .001). CONCLUSIONS We found a substantial color-code disagreement among devices in patients with relapsing-remitting multiple sclerosis regarding the ON antecedent. In non-ON eyes, Spectralis yielded a significantly higher thinning for temporal quadrant than Cirrus, suggesting that N-site axonal analysis could define axonal damage in relapsing-remitting multiple sclerosis patients earlier than conventional RNFL analysis.

PERIPHERAL RETINAL VASCULITIS: Analysis of 110 Consecutive Cases and a Contemporary Reappraisal of Tubercular Etiology.

Purpose: Describe the clinical features and outcomes of patients with peripheral retinal vasculitis (RV) and describe clinical characteristics of presumed tubercular RV in a nonendemic setting. Methods: Retrospective cohort study of 110 consecutive patients with peripheral RV at a tertiary referral eye care center in the United Kingdom. Retinal vasculitis was defined as RV with vitritis associated with peripheral retinal ischemia. Patients who also had positive Quantiferon Gold in Tube test, positive tuberculin skin test, and/or other evidence of systemic tuberculosis such as biopsy were labeled with presumed tubercular RV. Treatment success was defined as resolution of inflammation, and successful tapering of oral corticosteroids to less than 10 mg/day or topical steroids to less than twice a day. Results: Mean age of the study population was 42.69 ± 14.95 years. Patients were predominantly Asian (49.1%) and Male (67.0%). A total of 73.2% had bilateral involvement. Sixty-nine (62.72%) patients had presumed tubercular RV. A total of 52.8% patients received antitubercular therapy, 65.5% received oral corticosteroids, and 17.3% required steroid-sparing oral immunosuppressive agents. A total of 85.19% of patients with presumed tubercular RV achieved treatment success with concurrent antitubercular therapy as against 75.61% of patients with nontubercular RV. Conclusion: This is the largest study of the epidemiology, clinical features, and outcomes of both peripheral RV and presumed tubercular RV to date. Presumed tubercular RV commonly seems to affect young males of Asian descent and had vitreous hemorrhage as common clinical findings and also demonstrated a good treatment outcome with antitubercular therapy.

Bruch's membrane opening changes and lamina cribrosa displacement in non-arteritic anterior ischaemic optic neuropathy

Purpose To describe the morphological changes in the lamina cribrosa (LC) and prelaminar tissue (PT) from eyes with non-arteritic anterior ischaemic optic neuropathy (NAION) using enhanced depth imaging (EDI) optical coherence tomography (OCT), and to evaluate whether these changes correlate with retinal nerve fibre layer (RNFL) thickness and visual acuity (VA). Design/methods A prospective case-control study was performed, including 17 study eyes with NAION and 17 control, uninvolved eyes from 17 patients. Eyes underwent scanning with Spectralis-OCT at onset, 2 and 6 months after NAION. Bruchs membrane opening (BMO), anterior LC surface depth (LCD), LC thickness and PT thickness (PTT) were compared between study and control eyes. Correlation analysis was performed to evaluate the association between these parameters, RNFL thickness and VA. Results At presentation, average PT was 58.6% thicker in NAION eyes compared with healthy control eyes (p=0.001), followed by a significant thinning at 2 and 6 months (p=0.001). A significant LC forward displacement was observed at 2 and 6 months (p=0.001). BMO progressively shrunk at 2 and at 6 months (p<0.05). A significant correlation was found between PTT and RNFL thickness (ρSpearman=0.544, p=0.024) at onset, as well as between PTT and RNFL changes at 6 months (ρSpearman=0.545, p=0.036). BMO and RNFL changes were also correlated at 6 months (ρSpearman=0.750, p=0.001). Conclusions At onset, a significant PT thickening, backward LC movement and BMO enlargement occurred in NAION eyes compared with unaffected eyes, and these changes significantly reversed during follow-up. PTT and RNFL changes were significantly correlated.

Factors associated to temporal artery biopsy result in suspects of giant cell arteritis: a retrospective, multicenter, case–control study

Purpose:  To evaluate the positivity rate of temporal artery biopsies (TAB) performed in suspects of giant cell arteritis (GCA) and to study the epidemiological and clinical factors associated to the biopsy result.

The Collaborative Ocular Tuberculosis Study (COTS)-1 Report 3: Polymerase Chain Reaction in the Diagnosis and Management of Tubercular Uveitis: Global Trends

ABSTRACT Purpose: To analyze the role of polymerase chain reaction (PCR) of ocular fluids in management of tubercular (TB) anterior, intermediate, posterior, and panuveitis. Methods: In Collaborative Ocular Tuberculosis Study (COTS)-1 (25 centers, n = 962), patients with TB-related uveitis were included. 59 patients undergoing PCR of intraocular fluids (18 females; 53 Asian Indians) were included. Results: 59 (6.13%) of COTS-1 underwent PCR analysis. PCR was positive for Mycobacterium TB in 33 patients (23 males; all Asian Indians). 26 patients were PCR negative (18 males). Eight patients with negative PCR had systemic TB. Anti-TB therapy was given in 18 negative and 31 PCR cases. At 1-year follow-up, five patients with positive PCR (15.15%) and three with negative PCR (11.54%) had persistence/worsening of inflammation. Conclusions: Data from COTS-1 suggest that PCR is not commonly done for diagnosing intraocular TB and positive/negative results may not influence management or treatment outcomes in the real world scenario.