Evolving Management of Optic Neuritis and
Multiple Sclerosis
By Anthony Arnold, MD
(AJO, June 2005)
Selected Quotes, In-context Paraphrases, and Commentary:
- “The typical course for idiopathic optic neuritis is one of
worsening visual function over days to weeks, followed by spontaneous
recovery. Pain typically resolves over days, often as visual
loss begins, and visual recovery usually begins within 2 to
3 weeks, stabilizing over months. In the ONTT [Optic Neuritis
Treatment Trial], acuity began to improve within 3 weeks in
79% and within 5 weeks in 93% of patients.
M & T Commentary:
While optic neuritis can be very frightening to patients, and
justifiably so, the prognosis for visual recovery is promising
for most all patients. Knowing these statistics can help
you when counseling these patients.
- “not all cases of optic neuritis improve, and the patients
must be advised that recovery, although the rule, is not guaranteed.”
M & T Commentary:
This, of course, is the downside, and must be made clear to
patients, as well.
- “Optic neuritis not uncommonly recurs in either the same or
the fellow eye. In the ONTT, 28% of patients developed recurrence
within 5 years and 35% at 10 years. Recurrence was more frequent
in patients who eventually developed MS.”
M & T Commentary:
Similar to herpes simplex disease, the recurrent nature of
optic neuritis must be explained to the patient; yet note
that these patients have a better than 50/50 chance of non-recurrence.
- “Multiple recurrences increased the frequency of severe
long-term visual loss”
M & T Commentary:
Hopefully, with the advent of newer therapies, recurrence rates
can be reduced, and thus the risk for visual compromise.
- “A report of the Quality Standards Committee of the American
Academy of Neurology in 2000 supported the use of high-dose
corticosteroids, either by an oral or intravenous route, in
cases requiring more rapid visual recovery.”
M & T Commentary:
It must be stressed - to doctor and patient alike - that after
two years, visual outcome was the same, whether treated or
not.
- “Risk of MS: Approximately 15% to 20% of MS cases present
as optic neuritis, and from 38% to 50% of MS cases develop
it at some point.”
M & T Commentary:
While not critical statistics, it is useful for astute clinicians
to be aware of these realities.
- “The most valuable predictor for the development of subsequent
CDMS [clinically definite MS] is the presence of white matter
abnormalities (demyelinating lesions) on brain MRIs.”
- “Although the presence of such lesions is not sufficient to
make the diagnosis of CDMS, it does provide evidence of multifocal
brain involvement and, in the clinical scenario of optic neuritis,
raises the risk significantly. In the ONTT, the 5-year risk
for CDMS was 16% with a normal brain MRI scan (0 lesions),
compared with 37% with one or two lesions and 51% with three
or more lesions. At ten years, the increased risk of CDMS:
no lesions 22% risk; and one or more lesions, 56% risk.”
M & T Commentary:
This is the prime reason to order an MRI scan in patients presenting
with optic neuritis. It enables the neurologist (and optometrist)
to more comprehensively counsel patients.
- “Immunomodulation Therapy: During the past decade, three
types of Immunomodulation agents (IMAs) have become available
for the treatment of RR-MS [relapsing-remitting MS]: interferon
beta-1b (Betaseron); interferon beta 1a (Avonex); and the
synthetic copolymer glatiramer acetate (Copaxone). These agents
have beneficial effects in reducing disability progression,
acute demyelinative inflammation, and total disease burden
in patients with established relapsing disease. IMA therapy
should be initiated upon establishing a diagnosis of definite
RR-MS.”
- “The findings of the CHAMPS [Study Group]: the risk of subsequent
CDMS was reduced at 2-year follow-up from 45% with placebo
to 34% with treatment.”
M & T Commentary:
While certainly unimpressive, we suspect almost all patients
would opt to receive such a therapeutic trial.
- “all patients with idiopathic demyelinative optic neuritis
must be advised of the therapeutic option of IMAs for reducing
the risk of MS. We believe that all patients with this form
of optic neuritis should be offered brain MRI, for two reasons:
- It is the single best predictor of the risk
for development of MS.
- The available data on benefit of IMAs only
applies to patients with at least two typical MRI white
matter lesions.”
- “expert recommendations range from treatment in all cases,
to treatment only in cases with at least two MRI lesions, to
treatment only for those who, on repeat MRI (3 to 6 months),
show newly active lesionsx The decision to initiate IMA therapy
after initially isolated optic neuritis requires careful discussion
of all aspects and consultation with a neurologist.”
M & T Commentary:
Because state-of- the- art therapy is obviously in a state
of flux, we are glad these decision burdens lie on the neurologist’s
shoulders.
- “Natalizumab, a human monoclonal antibody with specific
activity against "4$1 integrin, has recently been shown
to be effective in modifying the disease course in RR-MS.
The statins, particularly simvastatin, have been shown to
have immunomodulating effects in addition to their cholesterol-lowering
actions and have proved beneficial in trials of RR-MS.
M & T Commentary:
We believe the therapeutic landscape will steadily evolve
over many decades, so be sure to carefully follow the literature.
- “although therapy has no long-term effect on visual outcome,
both corticosteroid and IMAs may play roles in decreasing the
risk and severity of MS after optic neuritis.
M & T Commentary:
As can be seen, progress is steady in the area of optic neuritis
and multiple sclerosis. Gaining, and maintaining, a solid
base of knowledge can help optometrists better counsel their
patients, and more effectively interact with the neurological
community.
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