Clinical Pathways in Neuro-ophthalmology : An ... - E-Lib FK UWKS

Should Visual Evoked Potentials Be
Performed on Patients with Optic Neuritis?
Although the VEP is often abnormal in patients with ON (Ashworth, 1994; Brusa, 1999;
Fotiou, 1999; Frederiksen, 1999; Fuhr, 2001; Honan, 1990; Rinalduzzi, 2001), an abnormal
VEP in the setting of a clinically diagnosed ON does not alter the diagnostic or
treatment plan. The VEP does not provide additional prognostic information for visual
recovery or for the development of MS. We do not recommend routine use of VEP in
typical ON (class III–IV, level C). VEP may be useful in identifying a second site of
neurologic involvement (previous ON) to strengthen the clinical diagnosis of MS in
patients with no history or examination findings of an optic neuropathy (Celesia, 1990).
What Is the Treatment of Optic Neuritis?
Optic Neuritis 47
Although corticosteroids have been used for acute ON (Lessell, 1992; Sellebjerg, 1999;
Silberberg, 1993) and have been shown to improve symptoms in MS (Kapoor, 1998),
well-controlled data to support the treatment efficacy of steroids in ON have been
lacking until recently (Beck, 1992a). IV methylprednisolone (MP) treatment has been
reported to decrease CSF anti-MBP levels, intrathecal IgG synthesis, and CSF oligoclonal
bands; to decrease gadolinium enhancement of MS plaques (and presumably blood–
brain barrier disruption) on MR scan; and to improve clinical disability. Modulation of
the function of inflammatory cells may also contribute to the clinical efficacy or highdose
corticosteroids (Sellebjerg, 2000). The clinical effect of treatment might be due to
reduction of inflammation and myelin breakdown (Barkhoff, 1991a, 1992; Warren,
1994).
Rawson et al reported a more rapid visual recovery, but no difference in visual
outcome after 1 year in a double-blind, placebo-controlled, prospective study of 50
patients with ON treated with adrenocorticotropic hormone (ACTH) (Rawson, 1966).
Rose et al observed similarly more rapid improvement in patients with ON treated with
ACTH compared with placebo (Rose, 1970). Bowden et al, however, reported no benefit
from ACTH compared with placebo in 54 patients with ON (Bowden, 1974). Gould et al
reported a prospective, single-blind, controlled, randomized clinical trial of 74 patients
with ON who experienced more rapid improvement with a retrobulbar injection of
triamcinolone, but patients had no difference in outcome after 6 months (Gould, 1977).
In the ONTT, the patients were randomly assigned to one of three treatment arms in
the study:
1. IV methylprednisolone sodium succinate (250 mg every 6 hours for 3 days) followed
by oral prednisone (1 mg=kg daily) for 11 days.
2. Oral prednisone (1 mg=kg daily) for 14 days.
3. Oral placebo for 14 days, followed by a short oral taper.
The major conclusions of the ONTT related to treatment are summarized in Table 2–8.
Wakakura et al also performed a randomized trial of IV megadose methylprednisolone
in ON and found that treatment with steroids improved visual recovery at 3 weeks.
Visual function at 12 weeks and at 1 year, however, was the same as in control patients
(Wakakura, 1999a). Sellebjerg et al performed a randomized, controlled trial of oral