Optic
Neuritis and Ischemic
Overlapping Clinical
Optic Neuropathy
Profiles
Joseph F. Rizzo III, MD, Simmons Lessell, MD
\s=b\ A retrospective analysis of the clinical features of 81 patients with acute idiopathic optic neuritis and 58 patients with nonarteritic anterior ischemic optic neuropathy revealed a surprising overlap of manifestions. The rate of visual decline and the range of visual acuities were the same for both. Central scotomas and improvement in acuity were more common in optic neuritis, but occurred often enough in nonarteritic anterior ischemic optic neuropathy to limit their value as single diagnostic criteria. The similarities observed in this study suggest that it may be difficult to differentiate between optic neuritis and nonarteritic anterior ischemic optic neuropathy solely on nosologic grounds in some instances of acute, unilateral optic
neuropathy. (Arch Ophthalmol. 1991;109:1668-1672)
Tdiopathic
or
See also pp 1666 and 1673. of
neurogenic visual loss in many symptoms and signs, but have rather different prog¬ nostic implications. Patients with ON usually recover vision but are at high
adults, share
Accepted for publication August 12, 1991. From the Department of Ophthalmology,
Harvard Medical School and the Massachusetts Eye and Ear Infirmary, Boston, Mass. Reprint requests to Massachusetts Eye and Ear Infirmary, 243 Charles St, Boston, MA 02114
(Dr Rizzo).
overlap.
demyelinative optic
neuritis (ON) and nonarteritic ante¬ rior ischemie optic neuropathy (AION), two of the most common
causes
risk for the development of multiple sclerosis.1 Patients with AION are thought to have little prospect for im¬ provement, but are not predisposed to multiple sclerosis.2,3 For these and oth¬ er reasons it is important for the clini¬ cian to differentiate between these neuropathies, preferably in the acute stage before prognostic and therapeu¬ tic considerations become moot. In most cases, this is easily accomplished by consideration of the presence or absence of disc edema or pain, the age of the patient, the mode of onset, and certain other features. However, there are instances in which use of these criteria proves misleading. This led us to conduct a retrospective analysis of a cohort of patients with ON and AION to determine the extent to which the clinical features of these disorders SUBJECTS AND METHODS All cases coded as ON or AION were identified in the computerized patient data¬ base of the neuro-ophthalmology unit at the Massachusetts Eye and Ear Infirmary, Boston. Patients selected for this investiga¬ tion included only those with idiopathic ON and AION whose history and physical ex¬ amination had been conducted by one or both of us within 2 weeks of the first visual symptom and followed up until their visual function recovered or stabilized. All followup periods exceeded 4 months. Patients with biopsy-proved or presumed arteritic AION and patients with a known or sus¬
pected hereditary, infectious, granulomatous, or vasculitic basis for neuropathy were
excluded. The database also has
an
"optic neuropathy, type unknown" catego¬ ry, consisting of patients with optic neurop-
Downloaded From: http://archopht.jamanetwork.com/ by a University of Pennsylvania User on 06/18/2015
athy that could not be classified, and a "posterior ischemie optic neuropathy" cate¬ gory. None of these patients were included in this study. In every case, the diagnosis used in our analyses was the one assigned at presentation by one of us and was not altered. A total of 223 patients with ON and 143 patients with AION were identified. Although the original diagnoses had been assigned by experienced clinicians, they were made with varying degrees of confi¬ dence. We, therefore, attempted to identify patients with ON and AION in whom the diagnosis could be accepted retrospectively with greater confidence. The "gold stan¬ dard" criterion for patients with ON was the development of multiple sclerosis (81 patients). The "gold standard" criteria for patients with AION were as follows: ab¬ sence of pain, presence of disc edema, and
age greater than 60 years (n 58). All were unilateral cases. The following information was abstracted and tabulated from each patient's chart: age; sex; initial, worst, and final Snellen visual acuities; presence or absence of pain; interval from first visual symptom(s) to worst vision, type of field defect; whether visual loss was first recognized on awaken¬ ing in the morning; evidence of multiple sclerosis; appearance of the optic nerve head at the time of initial evaluation; and whether a patient had been treated with corticosteroids. We also recorded visual "improvement," which was defined as a final Snellen visual acuity at least three lines better than at visual nadir. However, if the worst visual acuity was 20/25 or better, "improvement" was defined as the ability to read at least two more lines on the Snellen chart. Visual field testing was per¬ formed by us using a Goldmann perimeter or a 2-m tangent screen. Abnormalities were divided into central scotoma, altitudi¬ nal defect, Bjerrum's scotoma, nasal step, depression of peripheral isopter, "other" field defect, or "unreliable." =
Clinical Features of Patients as Having Optic Neuritis and Nonarteritic Anterior Ischemie
Diagnosed
Optic Neuropathy Anterior
ischemie
Optic Neuritis Features
(n
Mean age, y
Female-male ratio Visual loss on
awakening, % Progression >24 h, % Average time to visual nadir, d Improvement, %* Pain, %
-
81)
=
33 2.7:1
69 1:1.1
10 54
9 36
4.7
3.4
65 69
...t
Field defect, %
Central
59
Altitudinal Inferior
10
50 50
Superior *The criteria
Optic Neuropathy (n 58)
16
26 48 79 21
used to define improvement are described in the "Subjects and Methods" section. tPain was an exclusion criterion for anterior is¬ chemie
Fig 1.—Age distributions for "gold standard" patients with idiopathic optic neuritis (solid line) and nonarteritic anterior ischemie optic neuropathy (dashed line) displayed as the percentage of the total number of patients with each condition (81 and 58, respectively). See text for "gold standard" criteria.
optic neuropathy.
RESULTS
The Table summarizes data obtained from the patients. Figure 1 displays the age distribu¬ tions of the patients studied. Because age greater than 60 years was a crite¬ rion for inclusion in the AION group, the age distributions falsely indicate that there was essentially no overlap in the ages of patients with AION and ON. However, one can obtain a broad¬ er perspective of the age distributions by considering all 223 cases of ON and 143 cases of AION originally identified in the database (Fig 2). There was a 2.7:1 preponderance of women among patients with ON. No gender difference was found among patients with AION (female-male ra¬
tio, 1.1:1).
The Snellen visual acuity distribu¬ tions were remarkably similar for pa¬ tients with AION and ON (Fig 3). The progression of the two optic neuropathies is shown in Fig 4. Visual loss was maximal within 24 hours in 46% of the patients with ON and in 64% of the AION group. Progression over more than 10 days occurred in 23% of the patients with ON and in 9% of the AION group. The mean time to visual nadir was similar in the two disorders: 4.7 days for ON and 3.4 days for AION. Ten percent of the ON group and 9% of the AION group first recognized loss of vision on awakening from sleep in the morning. Pain was reported by 69% of the patients with ON. Absence of pain was an AION inclusion criterion; however,
Fig 2.—Age distributions for the "total" populations of patients with idiopathic optic neuritis (solid line) and nonarteritic anterior ischemie optic neuropathy (dashed line) displayed as the percent¬ age of patients with each condition (223 and 143, respectively). it should be noted that 8% of the 143 AION cases originally identified in the database (see above) reported pain. The patterns of visual field abnor¬ malities encountered in the two disor¬ ders are shown in Fig 5. Patients with ON predominantly had central scoto¬ mas. When they had altitudinal de¬ fects, they were as likely to be superi¬ or as inferior. On the other hand, patients with AION predominantly had altitudinal defects, and these de¬ fects overwhelmingly involved the in¬ ferior visual field. The disparity be¬ tween involvement of superior and inferior fields in patients with AION was
statistically significant (P
Neuritis and Ischemic
Overlapping Clinical
Optic Neuropathy
Profiles
Joseph F. Rizzo III, MD, Simmons Lessell, MD
\s=b\ A retrospective analysis of the clinical features of 81 patients with acute idiopathic optic neuritis and 58 patients with nonarteritic anterior ischemic optic neuropathy revealed a surprising overlap of manifestions. The rate of visual decline and the range of visual acuities were the same for both. Central scotomas and improvement in acuity were more common in optic neuritis, but occurred often enough in nonarteritic anterior ischemic optic neuropathy to limit their value as single diagnostic criteria. The similarities observed in this study suggest that it may be difficult to differentiate between optic neuritis and nonarteritic anterior ischemic optic neuropathy solely on nosologic grounds in some instances of acute, unilateral optic
neuropathy. (Arch Ophthalmol. 1991;109:1668-1672)
Tdiopathic
or
See also pp 1666 and 1673. of
neurogenic visual loss in many symptoms and signs, but have rather different prog¬ nostic implications. Patients with ON usually recover vision but are at high
adults, share
Accepted for publication August 12, 1991. From the Department of Ophthalmology,
Harvard Medical School and the Massachusetts Eye and Ear Infirmary, Boston, Mass. Reprint requests to Massachusetts Eye and Ear Infirmary, 243 Charles St, Boston, MA 02114
(Dr Rizzo).
overlap.
demyelinative optic
neuritis (ON) and nonarteritic ante¬ rior ischemie optic neuropathy (AION), two of the most common
causes
risk for the development of multiple sclerosis.1 Patients with AION are thought to have little prospect for im¬ provement, but are not predisposed to multiple sclerosis.2,3 For these and oth¬ er reasons it is important for the clini¬ cian to differentiate between these neuropathies, preferably in the acute stage before prognostic and therapeu¬ tic considerations become moot. In most cases, this is easily accomplished by consideration of the presence or absence of disc edema or pain, the age of the patient, the mode of onset, and certain other features. However, there are instances in which use of these criteria proves misleading. This led us to conduct a retrospective analysis of a cohort of patients with ON and AION to determine the extent to which the clinical features of these disorders SUBJECTS AND METHODS All cases coded as ON or AION were identified in the computerized patient data¬ base of the neuro-ophthalmology unit at the Massachusetts Eye and Ear Infirmary, Boston. Patients selected for this investiga¬ tion included only those with idiopathic ON and AION whose history and physical ex¬ amination had been conducted by one or both of us within 2 weeks of the first visual symptom and followed up until their visual function recovered or stabilized. All followup periods exceeded 4 months. Patients with biopsy-proved or presumed arteritic AION and patients with a known or sus¬
pected hereditary, infectious, granulomatous, or vasculitic basis for neuropathy were
excluded. The database also has
an
"optic neuropathy, type unknown" catego¬ ry, consisting of patients with optic neurop-
Downloaded From: http://archopht.jamanetwork.com/ by a University of Pennsylvania User on 06/18/2015
athy that could not be classified, and a "posterior ischemie optic neuropathy" cate¬ gory. None of these patients were included in this study. In every case, the diagnosis used in our analyses was the one assigned at presentation by one of us and was not altered. A total of 223 patients with ON and 143 patients with AION were identified. Although the original diagnoses had been assigned by experienced clinicians, they were made with varying degrees of confi¬ dence. We, therefore, attempted to identify patients with ON and AION in whom the diagnosis could be accepted retrospectively with greater confidence. The "gold stan¬ dard" criterion for patients with ON was the development of multiple sclerosis (81 patients). The "gold standard" criteria for patients with AION were as follows: ab¬ sence of pain, presence of disc edema, and
age greater than 60 years (n 58). All were unilateral cases. The following information was abstracted and tabulated from each patient's chart: age; sex; initial, worst, and final Snellen visual acuities; presence or absence of pain; interval from first visual symptom(s) to worst vision, type of field defect; whether visual loss was first recognized on awaken¬ ing in the morning; evidence of multiple sclerosis; appearance of the optic nerve head at the time of initial evaluation; and whether a patient had been treated with corticosteroids. We also recorded visual "improvement," which was defined as a final Snellen visual acuity at least three lines better than at visual nadir. However, if the worst visual acuity was 20/25 or better, "improvement" was defined as the ability to read at least two more lines on the Snellen chart. Visual field testing was per¬ formed by us using a Goldmann perimeter or a 2-m tangent screen. Abnormalities were divided into central scotoma, altitudi¬ nal defect, Bjerrum's scotoma, nasal step, depression of peripheral isopter, "other" field defect, or "unreliable." =
Clinical Features of Patients as Having Optic Neuritis and Nonarteritic Anterior Ischemie
Diagnosed
Optic Neuropathy Anterior
ischemie
Optic Neuritis Features
(n
Mean age, y
Female-male ratio Visual loss on
awakening, % Progression >24 h, % Average time to visual nadir, d Improvement, %* Pain, %
-
81)
=
33 2.7:1
69 1:1.1
10 54
9 36
4.7
3.4
65 69
...t
Field defect, %
Central
59
Altitudinal Inferior
10
50 50
Superior *The criteria
Optic Neuropathy (n 58)
16
26 48 79 21
used to define improvement are described in the "Subjects and Methods" section. tPain was an exclusion criterion for anterior is¬ chemie
Fig 1.—Age distributions for "gold standard" patients with idiopathic optic neuritis (solid line) and nonarteritic anterior ischemie optic neuropathy (dashed line) displayed as the percentage of the total number of patients with each condition (81 and 58, respectively). See text for "gold standard" criteria.
optic neuropathy.
RESULTS
The Table summarizes data obtained from the patients. Figure 1 displays the age distribu¬ tions of the patients studied. Because age greater than 60 years was a crite¬ rion for inclusion in the AION group, the age distributions falsely indicate that there was essentially no overlap in the ages of patients with AION and ON. However, one can obtain a broad¬ er perspective of the age distributions by considering all 223 cases of ON and 143 cases of AION originally identified in the database (Fig 2). There was a 2.7:1 preponderance of women among patients with ON. No gender difference was found among patients with AION (female-male ra¬
tio, 1.1:1).
The Snellen visual acuity distribu¬ tions were remarkably similar for pa¬ tients with AION and ON (Fig 3). The progression of the two optic neuropathies is shown in Fig 4. Visual loss was maximal within 24 hours in 46% of the patients with ON and in 64% of the AION group. Progression over more than 10 days occurred in 23% of the patients with ON and in 9% of the AION group. The mean time to visual nadir was similar in the two disorders: 4.7 days for ON and 3.4 days for AION. Ten percent of the ON group and 9% of the AION group first recognized loss of vision on awakening from sleep in the morning. Pain was reported by 69% of the patients with ON. Absence of pain was an AION inclusion criterion; however,
Fig 2.—Age distributions for the "total" populations of patients with idiopathic optic neuritis (solid line) and nonarteritic anterior ischemie optic neuropathy (dashed line) displayed as the percent¬ age of patients with each condition (223 and 143, respectively). it should be noted that 8% of the 143 AION cases originally identified in the database (see above) reported pain. The patterns of visual field abnor¬ malities encountered in the two disor¬ ders are shown in Fig 5. Patients with ON predominantly had central scoto¬ mas. When they had altitudinal de¬ fects, they were as likely to be superi¬ or as inferior. On the other hand, patients with AION predominantly had altitudinal defects, and these de¬ fects overwhelmingly involved the in¬ ferior visual field. The disparity be¬ tween involvement of superior and inferior fields in patients with AION was
statistically significant (P
