 |
 |

Longitudinal Brain Volume Measurement in Multiple Sclerosis
Rate of Brain Atrophy Is Independent of the Disease Subtype
Nynke F. Kalkers, MD, PhD;
Najim Ameziane, MSci;
Joost C. J. Bot, MD;
Arjan Minneboo, MD;
Chris H. Polman, MD, PhD;
Frederik Barkhof, MD, PhD
Arch Neurol. 2002;59:1572-1576.
Background In multiple sclerosis (MS), brain atrophy depicted by magnetic resonance
imaging reflects overall tissue loss, including axonal loss.
Objective To determine the course of atrophy by studying the rate of development
of brain atrophy in patients who have different subtypes of MS.
Methods Eighty-three patients with MS (42 with relapsing-remitting, 21 with
secondary progressive, and 20 with primary progressive) were studied longitudinally,
with an interval of 2 to 4 years. Magnetic resonance imaging included T1-
and T2-weighted images to obtain 2 brain volume measurements: (1) the parenchymal
fraction as a marker of global brain atrophy and (2) the ventricular fraction
as a marker of central atrophy. The annualized rate of global and central
brain atrophy was compared between those with different subtypes of MS and
related to clinical characteristics, including sex, age, disease duration,
and disability.
Results There was a significant decrease of the parenchymal fraction (-0.7%
per year; SEM, 0.11% per year) and a significant increase of ventricular fraction
(3.7% per year; SEM, 0.54% per year) in the total group. Significant tissue
loss was also seen in all 3 subtypes of MS; the decrease in parenchymal fraction
was not different between subtypes, whereas the increase in ventricular fraction
tended to be larger in patients with secondary progressive MS compared with
patients with primary progressive MS. Marginal associations were found between
clinical determinants and the rate of brain atrophy. Annualized increase in
the ventricular fraction was correlated with age (r
= -0.26) and duration of symptoms (r = -0.22):
younger patients (mainly patients with relapsing-remitting MS who have a limited
disability) displayed a larger increase in ventricular fraction compared with
older patients.
Conclusions The rate of development of brain atrophy is largely independent of the
course of the disease and other clinical characteristics. The relentless loss
of tissue occurring in MS is not restricted to later (progressive) phases
of the disease, thereby stressing the need for early neuroprotective treatment
in MS.
From the Departments of Neurology (Drs Kalkers and Polman) and Radiology
(Mr Ameziane and Drs Bot, Minneboo, and Barkhof), Vrije Universiteit Medical
Center, Amsterdam, the Netherlands.
|