Pathophysiology
The lesions of the Balo sclerosis belong to the MS lesion pattern III (distal oligodendrogliopathy).
According with Dr. Lucchinetti investigations, in Balo's concentric sclerosis, the rings may be caused by a physiological hypoxia (similar to that caused by some toxins or viruses) in the lesion, which is in turn countered by expression of stress proteins at the border. This expression and counter-expression forms rings of preserved tissue within the lesion and rings of demyelinated tissue just beyond where the previous attack had induced the protective stress proteins. Hence, subsequent attacks form concentric rings.
Ultimately, this expanding lesion causes the progressive picture typically seen. However, in some patients, the pathology underlying the disease appears to burn out and hence the disease may halt, hence the patients who spontaneously recover. The mechanisms triggering attacks and recovery remain uncertain.
Recently, a mathematical model for concentric sclerosis has been proposed. Authors review the previous pathogenic theories, discuss the link between concentric sclerosis and Liesegang's periodic precipitation phenomenon and propose a new mechanism based on self-organization.
Read more about this topic: Balo Concentric Sclerosis