The Clinical Profile of Experience
of the
Optic
Optic
Neuritis
Neuritis Treatment Trial
Optic Neuritis Study Group
\s=b\ The baseline characteristics of 448
eligible patients entered
into the Optic Neuritis Treatment Trial are described in an effort to summarize the clinical profile of acute optic neuritis. A total of 77.2% of the patients were women. Mean age was 31.8 years. Pain accompanied the visual loss in 92.2% of cases. The optic disc appeared swollen in 35.3% of the patients and normal in 64.7%. A wide variety of visual field defects were present. Abnormalities in asymptomatic fellow eyes were noted, particularly on peri-
metry.
Magnetic
resonance
imaging
showed changes consistent with demyelination of the brain in 48.7% of the
patients. Magnetic resonance imaging, serologic studies (such as the antinuclear antibody test and the fluorescent treponemal antibody absorption test), chest roentgenography, and lumbar puncture were of limited utility in defining a cause for visual loss other than optic neuritis associated with demyelinative disease.
(Arch Ophthalmol. 1991;109:1673-1678) neuritis is an inflammatory, (")ptic demyelinating disease of the optic nerve.
The value of corticosteroid
treatment for this condition is
investigated
in the
Optic
being
Neuritis
Accepted for publication August 24, 1991. From the Optic Neuritis Treatment Trial Headquarters, University of South Florida College of Medicine, Tampa. Reprint requests to Optic Neuritis Treatment Trial Headquarters, University of South Florida College of Medicine, 12901 N Bruce B. Downs Blvd, Tampa, FL 33612 (Roy W. Beck, MD, MPH).
Treatment Trial (ONTT), a multi¬ center collaborative study funded by the National Eye Institute of the Na¬ tional Institutes of Health, Bethesda, Md.1 On entry into the study, each patient underwent an extensive, stan¬ dardized evaluation. Using these data, the objectives of this report were (1) to
tent with unilateral optic neuritis, with visual symptoms of 8 days' duration or less; a relative afferent pupillary defect; and a visual field defect in the affected eye. Using the STATPAC software available with the Humphrey field analyzer (Allergan Hum¬ phrey, San Leandro, Calif), the minimum visual field defect was defined as one of the
following: (1)
mean
deviation, pattern SD,
corrected pattern SD value below the age-specific 95% confidence limits, or (2) eight of the 76 test points with sensitivity values on total deviation below the 95% confidence limits for age-specific normal values. If a patient did not have a relative afferent pupillary defect because of docu¬ mented previous optic neuritis in the fellow eye but met all other eligibility criteria, the patient could be entered with the approval of the study chairman. Table 2 contains a listing of the major exclusion criteria. For each patient entered into the study, a detailed history in regard to visual symp¬ toms; presence of pain; and past ocular, neurologic, and systemic problems was elic¬ ited, and standardized ocular and visual function examinations were performed, as described below. Additional testing included a standard¬ ized neurologic examination, standardized MRI of the head, blood tests (glucose, antinuclear antibody [ANA], and fluores¬ cent treponemal antibody absorption [FTAABS1 tests), and a chest roentgenogram. From the results of the neurologic history and examination, each patient was classi¬ fied according to the clinical criteria of Poser et al2 as having "no," "possible," "probable," or "definite" multiple sclerosis. Each MRI scan was assessed at a central reading center and categorized as one of five grades, based on the severity of changes typical for multiple sclerosis (grade 0, normal; grade I, changes not specific for or
See also pp 1666 and 1668. establish the clinical profile of acute optic neuritis with regard to present¬ ing symptoms, signs, and deficits in visual function; (2) to determine the value of magnetic resonance imaging (MRI), chest roentgenography, and se¬ rologie studies in treatment of pa¬ tients; and (3) to document the clinical characteristics of optic neuritis as an aid in designing future studies. MATERIALS AND METHODS Methods The organizational structure of the ONTT consists of the study headquarters at the University of South Florida, Tampa (responsible for coordination of the study), the Data Coordinating Center at George Washington University, Washington, DC (responsible for data management and anal¬ ysis), and the Visual Field Reading Center at the University of California, Davis (re¬ sponsible for evaluation of the visual fields). Patient recruitment was conducted at 15 clinical centers throughout the United States (Table 1). Before entry into the study, eligible patients signed an informed consent form approved by the Investiga¬ tional Review Board of each institution. Eligibility criteria for enrollment includ¬ ed the following: age range, 18 to 45 years inclusive; an acute clinical syndrome consis-
Downloaded From: http://archopht.jamanetwork.com/ by a Yale University User on 05/15/2015
multiple sclerosis; grades II-IV, changes consistent with multiple sclerosis with the
Table 1.—No. of Patients Enrolled in the Optic Neuritis Treatment Trial by Clinic Clinic No.
No. of Patients
Name and Location
University of Arkansas, Little Rock Cullen Eye Institute, Houston, Tex. Pacific Presbyterian Medical Center, San Francisco, Calif Duke University Medical Center, Durham, NC University of Florida, Gainesville Georgetown University, Washington, DC University of Illinois, Chicago University of Iowa, Iowa City Wills Eye Hospital, Philadelphia, Pa The Johns Hopkins Hospital, Baltimore, Md W. K. Kellogg Eye Center, Ann Arbor, Mich Michigan State University, East Lansing New York University Medical Center, New York Good Samaritan Hospital, Portland, Ore University of Washington, Seattle
12
13 15
18 "
27 _
26 28
24
30 457
Total
This clinic was transferred from the University of California, San Diego, to Pacific Presbyterian Medical Cen¬ ter, San Francisco, in the middle of the study. .
Table 2.—Major
.
Eligibility
.
and Exclusion Criteria
Criteria
Eligibility Presence of acute unilateral optic neuritis of unknown or demyelinative origin Visual symptoms for 6 D (spherical eqiuivalent) or hyperopia or astigmatism measuring 3 D in the af¬
fected eye Narrow angle glaucoma induced by pupillary dilation Intraocular pressure >30 mm Hg in affected eye currently or in the past, with or without treatment. Patient receiving medication that may produce retinal or optic nerve toxicity (eg, ethambutol, plaquenil,
phenothiazines)
Patient received systemic corticosteroid treatment within the past 3 mo or for >7 d within the Blood pressure >180 mm Hg systolic or 110 a
or corticotropin for any condition for any duration past 6 mo mm Hg diastolic; heart rate >120/min or presence of
pathologic arrhythmia
Blood glucose level >11.1 mmol/L in (which would exclude the patient)
a
patient
severity increasing
at the higher grades). Lumbar puncture, although not mandatory for participation in the study, was per¬ formed on 141 patients. The MRI grading system and results of the cerebrospinal fluid studies will be reported in separate articles.
Visual Function Tests
Individuals administering refraction and visual function tests were trained to use standardized techniques. Testing equip¬ ment and illumination requirements were standardized and checked at yearly site visits. All testing was performed before
who is not
receiving medical
treatment for diabetes
pupillary dilation. When visual acuity was light perception only or no light perception, perimetry, contrast sensitivity, and color vision testing were not attempted. The protocols followed for each of the testing procedures are detailed in the Optic Neuri¬ tis Treatment Trial Manual of Procedures3
(available from the National Technical In¬ formation Service). Visual Acuity.—After full refractive cor¬ rection was measured, visual acuity was tested using a retroilluminated Bailey-Lo¬ vie chart4 at a distance of 4 m. For patients who could not read any letters on the chart at 1 m, the ability to count fingers, to
Downloaded From: http://archopht.jamanetwork.com/ by a Yale University User on 05/15/2015
identify hand movement, and to perceive light was ascertained. For purposes of sta¬ tistical analysis, the visual acuity score was converted to logmar units. A logmar value of 1.70 was assigned when no letters were correctly identified. Visual acuity was con¬ sidered to be abnormal if the logmar value was greater than 0 (equivalent to 20/20). Color Vision.—Both pseudoisochromatic Ishihara (Kanehara and Co LTD, Tokyo, Japan) plates (11 plates) and the Farns-
worth-Munsell 100-hue test (FM 100, Mac¬ beth Div, Kollmorgen Corp, Baltimore, Md), with a lamp providing a color tempera¬ ture of 6200°K were used to assess color vision. Vision was considered to be abnor¬ mal if one or more Ishihara plates were missed. For the FM 100 test, the square root of the error score was used for data analysis. A score of 36.6 (the square root of 1338) was assigned when vision was too poor to perform the test. Scores greater than or equal to 10.5 (the square root of 110) were considered abnormal based on the reported 95% confidence interval.'' Contrast Sensitivity.—The Pelli-Robson letter chart was used to measure contrast sensitivity at a testing distance of 1 m, at which the letters subtend a visual angle of 3°. This test consists of 16 triplets of letters that range in contrast from approximately 96% to 1%. In previous studies, this test has been shown to have a strong correlation with peak contrast sensitivity measured with sine wave gratings.6'' To determine the normal range for contrast sensitivity as measured in this study, 140 normal subjects without any evidence of ocular disease and in the same age range as our patients, were tested using the ONTT protocol. Based on the 95% confidence interval from this data, scores less than 1.75 log units were consid¬ ered abnormal. Visual Field.-The central 30° of the visual field was evaluated with program 302 on the Humphrey field analyzer and the peripheral field was evaluated by the plot¬ ting of I3e and II4e isopters on the Goldmann perimeter. The processing and classi¬ fication of the fields by the Visual Field Reading Center will be detailed in a sepa¬ rate publication. The foveal threshold, mean deviation, and corrected pattern SD were analyzed using STATPAC. In addi¬ tion, the average thresholds within the central 10° (zone 1), between 10° and 20° (zone 2), and between 20° and 30° (zone 3) were calculated. For the Goldmann fields, the area within each isopter (zone 4 for the I3e and zone 5 for the H4e) was determined using a graphics tablet. For each patient, field loss was classified as diffuse or local. Fields with local defects were classified into one of 14 patterns of visual field loss, based primarily on the Humphrey field. Age-adjusted values be¬ tween -32.27 dB and -34.14 dB were assigned for mean deviation and values between 1.70 and 2.08 dB for corrected pattern SD when vision was too poor to attempt the field. Based on a 95% confi¬ dence interval from a normal age-matched data set collected by the Visual Field Read¬ ing Center, values of mean deviation less than -3.00 dB were considered abnormal.
Table 3.—Demographic and Clinical Characteristics of 448 Patients at Entry Into Study % of Patients
Characteristic
Demographic
Women White Mean ± SD age, y
77.2 85.0 31 8 ± 6.7
Historical features Visual symptoms Intermittent blurring
1.3
40.0
Blurred Scotoma
44.6 8.0
Complete loss of vision Other descriptions Change in vision between
6.0
onset and examination
No
change Progression Improvement Positive visual phenomena Colors or flashing lights Ocular pain present
26.1 69.0
4.9 30.4 92.2 50.1
Mild
37.5
Moderate Severe Character of pain Constant
Constant,
12.3 7.3 51.3
worse on
eye movement movement only Intermittent, unrelated
Eye
35.8 3.4
to
eye movement Other Visual acuities in affected eyes 20/20 or better
2.2
10.5 24.8
20/25-20/40
20/50-20/190 20/200-20/800
28.8 20.3 3.6 5.6
Finger counting Hand motion Light perception No light perception Fundus findings
Optic
3.3 3.1
disc
64.7
Normal Swollen Disc or peripapillary
35.3 5.6
hemorrhages
Retinal exudates Vitreous cells (trace) Multiple sclerosis No Possible Probable Definite
Magnetic
resonance
imaging of brain
Grade 0 Grade I Grade II Grade III Grade IV
1.8 3.3 66.9 19.9 7.6 5.6 "
40.3 11.0 9.3
6.8 32.5
Antinuclear antibody titer 0 < 1:320 > 1:320
*N
=
83.7
12.9 3.4
418.
RESULTS
Four hundred fifty-seven subjects entered into the ONTT between July 1, 1988, and June 30, 1991, at the 15 clinics (Table 1). Nine subjects sub¬ sequently were determined to be ineli¬ gible because of optic disc pallor in the affected eye (n 1), reliability indexes on the baseline Humphrey field exwere
=
ceeded ( 3), findings more sugges¬ tive of anterior ischemie optic neuropa¬ thy than optic neuritis (painless optic disc edema with altitudinal field de¬ fect) (n 3), and misdiagnosis of optic neuritis (n 2). The two misdiagnosed patients had histories and examination findings consistent with optic neuritis, but one of them was subsequently de¬ termined to have an ophthalmic artery aneurysm and the other had a pituitary tumor. This report provides the data collected on the 448 eligible subjects. =
=
=
Demographic and Clinical Characteristics
Table 3 summarizes the characteris¬ tics of the 448 patients. Mean age was 31.8 years, and 77.2% were women. The right eye was affected in 49.6% of cases. Symptoms of visual loss were present for 5.1 ±1.6 days before entry into the study. In the majority of pa¬ tients (69.0%) visual loss progressively worsened from the onset to the time of examination. Pain, usually worsened by eye movement, accompanied the visual loss in 92.2% of cases and actual¬ ly preceded the onset of visual symp¬ toms in 39.5%. The proportion of pa¬ tients with pain was similar whether the optic disc appeared swollen or nor¬ mal (91.1% and 93.8%, respectively). Approximately equal proportions of patients suffered mild (35.3% with vi¬ sual acuities of 20/40 or better), moder¬ ate (28.8% with visual acuities of 20/50 to 20/190), and severe (35.9% with visual acuities of 20/200 or worse) loss. Disc swelling (papillitis) was present in 35.3% of the patients. Swollen optic discs were noted in 40.3% of patients with visual symptoms of 5 to 8 days' duration, compared with 25.3% of pa¬ tients with visual symptoms of less than 5 days' duration ( 2 9.11; =
P
of the
Optic
Optic
Neuritis
Neuritis Treatment Trial
Optic Neuritis Study Group
\s=b\ The baseline characteristics of 448
eligible patients entered
into the Optic Neuritis Treatment Trial are described in an effort to summarize the clinical profile of acute optic neuritis. A total of 77.2% of the patients were women. Mean age was 31.8 years. Pain accompanied the visual loss in 92.2% of cases. The optic disc appeared swollen in 35.3% of the patients and normal in 64.7%. A wide variety of visual field defects were present. Abnormalities in asymptomatic fellow eyes were noted, particularly on peri-
metry.
Magnetic
resonance
imaging
showed changes consistent with demyelination of the brain in 48.7% of the
patients. Magnetic resonance imaging, serologic studies (such as the antinuclear antibody test and the fluorescent treponemal antibody absorption test), chest roentgenography, and lumbar puncture were of limited utility in defining a cause for visual loss other than optic neuritis associated with demyelinative disease.
(Arch Ophthalmol. 1991;109:1673-1678) neuritis is an inflammatory, (")ptic demyelinating disease of the optic nerve.
The value of corticosteroid
treatment for this condition is
investigated
in the
Optic
being
Neuritis
Accepted for publication August 24, 1991. From the Optic Neuritis Treatment Trial Headquarters, University of South Florida College of Medicine, Tampa. Reprint requests to Optic Neuritis Treatment Trial Headquarters, University of South Florida College of Medicine, 12901 N Bruce B. Downs Blvd, Tampa, FL 33612 (Roy W. Beck, MD, MPH).
Treatment Trial (ONTT), a multi¬ center collaborative study funded by the National Eye Institute of the Na¬ tional Institutes of Health, Bethesda, Md.1 On entry into the study, each patient underwent an extensive, stan¬ dardized evaluation. Using these data, the objectives of this report were (1) to
tent with unilateral optic neuritis, with visual symptoms of 8 days' duration or less; a relative afferent pupillary defect; and a visual field defect in the affected eye. Using the STATPAC software available with the Humphrey field analyzer (Allergan Hum¬ phrey, San Leandro, Calif), the minimum visual field defect was defined as one of the
following: (1)
mean
deviation, pattern SD,
corrected pattern SD value below the age-specific 95% confidence limits, or (2) eight of the 76 test points with sensitivity values on total deviation below the 95% confidence limits for age-specific normal values. If a patient did not have a relative afferent pupillary defect because of docu¬ mented previous optic neuritis in the fellow eye but met all other eligibility criteria, the patient could be entered with the approval of the study chairman. Table 2 contains a listing of the major exclusion criteria. For each patient entered into the study, a detailed history in regard to visual symp¬ toms; presence of pain; and past ocular, neurologic, and systemic problems was elic¬ ited, and standardized ocular and visual function examinations were performed, as described below. Additional testing included a standard¬ ized neurologic examination, standardized MRI of the head, blood tests (glucose, antinuclear antibody [ANA], and fluores¬ cent treponemal antibody absorption [FTAABS1 tests), and a chest roentgenogram. From the results of the neurologic history and examination, each patient was classi¬ fied according to the clinical criteria of Poser et al2 as having "no," "possible," "probable," or "definite" multiple sclerosis. Each MRI scan was assessed at a central reading center and categorized as one of five grades, based on the severity of changes typical for multiple sclerosis (grade 0, normal; grade I, changes not specific for or
See also pp 1666 and 1668. establish the clinical profile of acute optic neuritis with regard to present¬ ing symptoms, signs, and deficits in visual function; (2) to determine the value of magnetic resonance imaging (MRI), chest roentgenography, and se¬ rologie studies in treatment of pa¬ tients; and (3) to document the clinical characteristics of optic neuritis as an aid in designing future studies. MATERIALS AND METHODS Methods The organizational structure of the ONTT consists of the study headquarters at the University of South Florida, Tampa (responsible for coordination of the study), the Data Coordinating Center at George Washington University, Washington, DC (responsible for data management and anal¬ ysis), and the Visual Field Reading Center at the University of California, Davis (re¬ sponsible for evaluation of the visual fields). Patient recruitment was conducted at 15 clinical centers throughout the United States (Table 1). Before entry into the study, eligible patients signed an informed consent form approved by the Investiga¬ tional Review Board of each institution. Eligibility criteria for enrollment includ¬ ed the following: age range, 18 to 45 years inclusive; an acute clinical syndrome consis-
Downloaded From: http://archopht.jamanetwork.com/ by a Yale University User on 05/15/2015
multiple sclerosis; grades II-IV, changes consistent with multiple sclerosis with the
Table 1.—No. of Patients Enrolled in the Optic Neuritis Treatment Trial by Clinic Clinic No.
No. of Patients
Name and Location
University of Arkansas, Little Rock Cullen Eye Institute, Houston, Tex. Pacific Presbyterian Medical Center, San Francisco, Calif Duke University Medical Center, Durham, NC University of Florida, Gainesville Georgetown University, Washington, DC University of Illinois, Chicago University of Iowa, Iowa City Wills Eye Hospital, Philadelphia, Pa The Johns Hopkins Hospital, Baltimore, Md W. K. Kellogg Eye Center, Ann Arbor, Mich Michigan State University, East Lansing New York University Medical Center, New York Good Samaritan Hospital, Portland, Ore University of Washington, Seattle
12
13 15
18 "
27 _
26 28
24
30 457
Total
This clinic was transferred from the University of California, San Diego, to Pacific Presbyterian Medical Cen¬ ter, San Francisco, in the middle of the study. .
Table 2.—Major
.
Eligibility
.
and Exclusion Criteria
Criteria
Eligibility Presence of acute unilateral optic neuritis of unknown or demyelinative origin Visual symptoms for 6 D (spherical eqiuivalent) or hyperopia or astigmatism measuring 3 D in the af¬
fected eye Narrow angle glaucoma induced by pupillary dilation Intraocular pressure >30 mm Hg in affected eye currently or in the past, with or without treatment. Patient receiving medication that may produce retinal or optic nerve toxicity (eg, ethambutol, plaquenil,
phenothiazines)
Patient received systemic corticosteroid treatment within the past 3 mo or for >7 d within the Blood pressure >180 mm Hg systolic or 110 a
or corticotropin for any condition for any duration past 6 mo mm Hg diastolic; heart rate >120/min or presence of
pathologic arrhythmia
Blood glucose level >11.1 mmol/L in (which would exclude the patient)
a
patient
severity increasing
at the higher grades). Lumbar puncture, although not mandatory for participation in the study, was per¬ formed on 141 patients. The MRI grading system and results of the cerebrospinal fluid studies will be reported in separate articles.
Visual Function Tests
Individuals administering refraction and visual function tests were trained to use standardized techniques. Testing equip¬ ment and illumination requirements were standardized and checked at yearly site visits. All testing was performed before
who is not
receiving medical
treatment for diabetes
pupillary dilation. When visual acuity was light perception only or no light perception, perimetry, contrast sensitivity, and color vision testing were not attempted. The protocols followed for each of the testing procedures are detailed in the Optic Neuri¬ tis Treatment Trial Manual of Procedures3
(available from the National Technical In¬ formation Service). Visual Acuity.—After full refractive cor¬ rection was measured, visual acuity was tested using a retroilluminated Bailey-Lo¬ vie chart4 at a distance of 4 m. For patients who could not read any letters on the chart at 1 m, the ability to count fingers, to
Downloaded From: http://archopht.jamanetwork.com/ by a Yale University User on 05/15/2015
identify hand movement, and to perceive light was ascertained. For purposes of sta¬ tistical analysis, the visual acuity score was converted to logmar units. A logmar value of 1.70 was assigned when no letters were correctly identified. Visual acuity was con¬ sidered to be abnormal if the logmar value was greater than 0 (equivalent to 20/20). Color Vision.—Both pseudoisochromatic Ishihara (Kanehara and Co LTD, Tokyo, Japan) plates (11 plates) and the Farns-
worth-Munsell 100-hue test (FM 100, Mac¬ beth Div, Kollmorgen Corp, Baltimore, Md), with a lamp providing a color tempera¬ ture of 6200°K were used to assess color vision. Vision was considered to be abnor¬ mal if one or more Ishihara plates were missed. For the FM 100 test, the square root of the error score was used for data analysis. A score of 36.6 (the square root of 1338) was assigned when vision was too poor to perform the test. Scores greater than or equal to 10.5 (the square root of 110) were considered abnormal based on the reported 95% confidence interval.'' Contrast Sensitivity.—The Pelli-Robson letter chart was used to measure contrast sensitivity at a testing distance of 1 m, at which the letters subtend a visual angle of 3°. This test consists of 16 triplets of letters that range in contrast from approximately 96% to 1%. In previous studies, this test has been shown to have a strong correlation with peak contrast sensitivity measured with sine wave gratings.6'' To determine the normal range for contrast sensitivity as measured in this study, 140 normal subjects without any evidence of ocular disease and in the same age range as our patients, were tested using the ONTT protocol. Based on the 95% confidence interval from this data, scores less than 1.75 log units were consid¬ ered abnormal. Visual Field.-The central 30° of the visual field was evaluated with program 302 on the Humphrey field analyzer and the peripheral field was evaluated by the plot¬ ting of I3e and II4e isopters on the Goldmann perimeter. The processing and classi¬ fication of the fields by the Visual Field Reading Center will be detailed in a sepa¬ rate publication. The foveal threshold, mean deviation, and corrected pattern SD were analyzed using STATPAC. In addi¬ tion, the average thresholds within the central 10° (zone 1), between 10° and 20° (zone 2), and between 20° and 30° (zone 3) were calculated. For the Goldmann fields, the area within each isopter (zone 4 for the I3e and zone 5 for the H4e) was determined using a graphics tablet. For each patient, field loss was classified as diffuse or local. Fields with local defects were classified into one of 14 patterns of visual field loss, based primarily on the Humphrey field. Age-adjusted values be¬ tween -32.27 dB and -34.14 dB were assigned for mean deviation and values between 1.70 and 2.08 dB for corrected pattern SD when vision was too poor to attempt the field. Based on a 95% confi¬ dence interval from a normal age-matched data set collected by the Visual Field Read¬ ing Center, values of mean deviation less than -3.00 dB were considered abnormal.
Table 3.—Demographic and Clinical Characteristics of 448 Patients at Entry Into Study % of Patients
Characteristic
Demographic
Women White Mean ± SD age, y
77.2 85.0 31 8 ± 6.7
Historical features Visual symptoms Intermittent blurring
1.3
40.0
Blurred Scotoma
44.6 8.0
Complete loss of vision Other descriptions Change in vision between
6.0
onset and examination
No
change Progression Improvement Positive visual phenomena Colors or flashing lights Ocular pain present
26.1 69.0
4.9 30.4 92.2 50.1
Mild
37.5
Moderate Severe Character of pain Constant
Constant,
12.3 7.3 51.3
worse on
eye movement movement only Intermittent, unrelated
Eye
35.8 3.4
to
eye movement Other Visual acuities in affected eyes 20/20 or better
2.2
10.5 24.8
20/25-20/40
20/50-20/190 20/200-20/800
28.8 20.3 3.6 5.6
Finger counting Hand motion Light perception No light perception Fundus findings
Optic
3.3 3.1
disc
64.7
Normal Swollen Disc or peripapillary
35.3 5.6
hemorrhages
Retinal exudates Vitreous cells (trace) Multiple sclerosis No Possible Probable Definite
Magnetic
resonance
imaging of brain
Grade 0 Grade I Grade II Grade III Grade IV
1.8 3.3 66.9 19.9 7.6 5.6 "
40.3 11.0 9.3
6.8 32.5
Antinuclear antibody titer 0 < 1:320 > 1:320
*N
=
83.7
12.9 3.4
418.
RESULTS
Four hundred fifty-seven subjects entered into the ONTT between July 1, 1988, and June 30, 1991, at the 15 clinics (Table 1). Nine subjects sub¬ sequently were determined to be ineli¬ gible because of optic disc pallor in the affected eye (n 1), reliability indexes on the baseline Humphrey field exwere
=
ceeded ( 3), findings more sugges¬ tive of anterior ischemie optic neuropa¬ thy than optic neuritis (painless optic disc edema with altitudinal field de¬ fect) (n 3), and misdiagnosis of optic neuritis (n 2). The two misdiagnosed patients had histories and examination findings consistent with optic neuritis, but one of them was subsequently de¬ termined to have an ophthalmic artery aneurysm and the other had a pituitary tumor. This report provides the data collected on the 448 eligible subjects. =
=
=
Demographic and Clinical Characteristics
Table 3 summarizes the characteris¬ tics of the 448 patients. Mean age was 31.8 years, and 77.2% were women. The right eye was affected in 49.6% of cases. Symptoms of visual loss were present for 5.1 ±1.6 days before entry into the study. In the majority of pa¬ tients (69.0%) visual loss progressively worsened from the onset to the time of examination. Pain, usually worsened by eye movement, accompanied the visual loss in 92.2% of cases and actual¬ ly preceded the onset of visual symp¬ toms in 39.5%. The proportion of pa¬ tients with pain was similar whether the optic disc appeared swollen or nor¬ mal (91.1% and 93.8%, respectively). Approximately equal proportions of patients suffered mild (35.3% with vi¬ sual acuities of 20/40 or better), moder¬ ate (28.8% with visual acuities of 20/50 to 20/190), and severe (35.9% with visual acuities of 20/200 or worse) loss. Disc swelling (papillitis) was present in 35.3% of the patients. Swollen optic discs were noted in 40.3% of patients with visual symptoms of 5 to 8 days' duration, compared with 25.3% of pa¬ tients with visual symptoms of less than 5 days' duration ( 2 9.11; =
P
