Kuchling et al. – Diffusion tensor imaging for multilevel assessment of the visual pathway: possibilities for personalized outcome prediction in autoimmune disorders of the central nervous system.

EPMA J. 2017 Jul 25;8(3):279-294

by Kuchling J, Brandt AU, Paul F, Scheel M.

The afferent visual pathway represents the most frequently affected white matter pathway in multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD). Diffusion tensor imaging (DTI) can reveal microstructural or non-overt brain tissue damage and quantify pathological processes. DTI facilitates the reconstruction of major white matter fiber tracts allowing for the assessment of structure-function and damage-dysfunction relationships. In this review, we outline DTI studies investigating the afferent visual pathway in idiopathic optic neuritis (ON), NMOSD, and MS. Since MS damage patterns are believed to depend on multiple factors, i.e., ON (anterior visual pathway damage), inflammatory lesions (posterior visual pathway damage), and global diffuse inflammatory and neurodegenerative processes, comprehensive knowledge on different contributing factors using DTI in vivo may advance our understanding of MS disease pathology. Combination of DTI measures and visual outcome parameters yields the potential to improve routine clinical diagnostic procedures and may further the accuracy of individual prognosis with regard to visual function and personalized disease outcome. However, due to the inherent limitations of DTI acquisition and post-processing techniques and the so far heterogeneous and equivocal data of previous studies, evaluation of the true potential of DTI as a possible biomarker for afferent visual pathway dysfunction is still substantially limited. Further research efforts with larger longitudinal studies and standardized DTI acquisition and post-processing validation criteria are needed to overcome current DTI limitations. DTI evaluation at different levels of the visual pathway has the potential to provide markers for individual damage evaluation in the future. As an imaging biomarker, DTI may support individual outcome prediction during personalized treatment algorithms in MS and other neuroinflammatory diseases, hereby leveraging the concept of predictive, preventive, and personalized medicine in the field of clinical neuroimmunology.

Albrecht et al. Optical coherence tomography for the diagnosis and monitoring of idiopathic intracranial hypertension

J Neurol. 2017 Jul;264(7):1370-1380

by Albrecht P, Blasberg C, Ringelstein M, Müller AK, Finis D, Guthoff R, Kadas EM, Lagreze W, Aktas O, Hartung HP, Paul F, Brandt AU, Methner A

(in cooperation with Universitätsklinikum Düsseldorf AG Albrecht)

The objectives of the study were to investigate the value of optical coherence tomography in detecting papilledema in patients with idiopathic intracranial hypertension (IIH), a disease which is difficult to monitor and which can lead to permanent visual deficits; to analyze retinal changes over time. In this non-interventional case-control study, spectral-domain optical coherence tomography (SD-OCT) was used to analyze the retinal and optic nerve head (ONH) morphology of 21 patients with IIH and 27 age- and sex-matched healthy controls over time. We analyzed the ONH volume using a custom-made algorithm and employed semi-automated segmentation of macular volume scans to assess the macular retinal nerve fiber layer (RNFL) and ganglion cell layer and inner plexiform layer complex as well as the total macular volume. In IIH patients, the ONH volume was increased and correlated with cerebrospinal fluid (CSF) pressure. The ONH volume decreased after the initiation of treatment with acetazolamide. The macular RNFL volume decreased by 5% in 3.5 months, and a stepwise multivariate regression analysis identified CSF pressure as the main influence on macular RNFL volume at diagnosis. The only factor predicting macular RNFL volume loss over time was ONH volume. SD-OCT can non-invasively monitor changes in retinal and ONH morphology in patients with IIH. Increased ONH volume leads to retinal atrophy in the form of macular RNFL volume loss, presumably due to mechanic jamming of the optic nerve at the disc and subsequent axonal loss.