apparently the nerve fiber layer is highly correlated with brain volume. Here's an abstract of interest
© 2007 American Academy of Neurology
Diagnostic accuracy of retinal abnormalities in predicting disease activity in MS
Jorge Sepulcre, MD, Manuel Murie-Fernandez, MD, Angel Salinas-Alaman, MD, Alfredo García-Layana, MD, Bartolome Bejarano, MD and Pablo Villoslada, MD
Objectives: To assess the association between the thickness of the retinal nerve fiber layer (RNFL), assessed by optical coherence tomography (OCT), retinal periphlebitis (RP), and multiple sclerosis (MS) disease activity.
Methods: We studied a prospective cohort of 61 patients and 29 matched controls for 2 years, performing a neurologic assessment every 3 months and an ophthalmologic evaluation, including OCT scans, every 6 months. Baseline MRI studies were also carried out from which brain volume and lesion load were assessed.
Results: We found that the RNFL thickness in patients with MS was thinner than in controls, particularly in the temporal quadrant (p = 0.004). Although RNFL atrophy was greater in patients who also had optic neuritis (p = 0.002), it also augmented in MS patients who did not have optic neuritis compared with controls (p = 0.014). RNFL atrophy was correlated with greater disability (r = –0.348, p = 0.001) and longer disease duration (r = –0.301, p = 0.003). Furthermore, baseline temporal quadrant RNFL atrophy was associated with the presence of new relapses and changes in the Expanded Disability Status Scale by the end of the study (p < 0.05 in all cases). Indeed, RNFL thickness was correlated with white matter volume (r = 0.291, p = 0.005) and gray matter volume (r = 0.239, p = 0.021). The presence of RP was a risk factor for having new relapses in the next 2 years (odds ratio = 1.52, p = 0.02), and patients with RP had larger gadolinium-enhancing lesions volume (p = 0.003).
Conclusion: Retinal nerve fiber layer atrophy and the presence of retinal periphlebitis are associated with disease activity, suggesting that retinal evaluation can be used as biomarkers of multiple sclerosis activity.
*Both authors contributed equally to this work.
Supported in part by the Spanish Ministry of Health (FIS PI051201), the "Fundacion Uriach" and by an unrestricted grant by Gemac SA (Cenon, France) to P.V. J.S. was a fellow of the Spanish Ministry of Health (FIS CM #05/00222).
Disclosure: The authors report no conflicts of interest.
Received September 16, 2006. Accepted in final form December 31, 2006.