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Abnormal Radionuclide Cerebral Angiograms and
Scans Due to Seizures 1

Nuclear
Medicine

Jeffrey S. Stevens, M.D. and Fred S. Mishkin, M.D.

The effect of recent seizures on the brain scan was determined in a retrospective study
of patients who had had seizures. All patients who underwent brain scanning within eight
days of seizures and who did not have a specific intracranial lesion were included. The
99mTc-pertechnetate cerebral angiogram and/or delayed scan was abnormal in 73% of
22 patients. The data suggest that if seizures occur within six days of the brain imaging,
the image is likelyto be abnormal.
INDEX TERMS:

Brain, radionuclide studies. Epilepsy

Radiology 117:113-115, October 1975

but the scan revealed a focal area of increased activity high in the
right parietal region (Figs. 5 and 6). Cerebral angiography demonstrated a vascular mass 2.5 cm in diameter in the same location
(Fig. 7). The mass, resected a year later at another hospital, was reportedto be a meningioma.

RAIN SCAN abnormalities in epilepsy have been
infrequently reported. "Faintly positive" scans
were noted in 6 patients in status epilepticus (1). Another report described an abnormal brain scan which reverted to normal in an infant with focal seizures (2).
Four additional cases in children (3) and increased perfusion to the affected hemisphere in two adults (4) were
recently reported.
We encountered a patient with focal seizures caused
by a lesion which was itself undetectable at the time of
the original abnormal radionuclide cerebral angiogram
and scan. A normal study after the seizures were controlled was followed 3 months later by a third scan
which revealed a focal lesion that was subsequently
confirmed by contrast angiography. The patient acted
as her own control to show that seizures alone were the
cause of the initial abnormal flow study and scan. This
stimulated us to review the brain scans and medical
records of all patients seen at our institution during the
past two years who had had seizures.

B

MATERIAL AND METHOD

All records coded as seizures over the past two
years were reviewed, and all patients who underwent
brain scanning within eight days of the seizures were included in this study. Twenty-two patients, ranging in age
from 5 months to 70 years, with seizures not due to
proven intracranial lesions, were found. All studies were
performed using 99mTc-pertechnetate. Following administration of oral perchlorate and the intravenous injection of a bolus of 25 mCi of 99mTc-pertechnetate (appropriately reduced for children), four-second arterial
and venous phase radionuclide angiographic images
were obtained using an Anger camera with a parallelhole collimator. Three hours later anterior, posterior,
vertex and both lateral images were obtained using a
dual probe 5-inch (12.7 ern) rectilinear scanner.

CASE REPORT

A 68-year-old black woman with no prior historyof neurologic disease experienced a classic Jacksonian seizure characterized by
twitching movements of the left hand, marching up the left upperextremity to the shoulder. An electroencephalogram the sameday was
abnormal in the right temporal region. She was treated with anticonvulsants and experienced only occasional seizures until three
months later when seizures began to occur at close intervals. On
the day of the study they were almost continuous. Pertechnetate
brain scanning, during which seizures occurred, revealed increased
activity in the right cortex on both the radionuclide angiogram and
delayed images (Figs. 1 and 2). The seizures were controlled, and
repeat pertechnetate angiography and scanning 12 days later were
normal(Figs. 3 and 4).
Three months later a third pertechnetate angiogram was normal,

RESULTS

The flow study was abnormal in 15 of 22 cases and
the delayed scan was abnormal in 9 of 22 cases. One
or the other was abnormal in 16 of 22 cases. The flow
study was abnormal in 15 of these 16 cases. The entire
study was normal in 6 of 22 cases (TABLE I).
The radionuclide angiographic abnormality consisted
of relative increased activity of the affected hemisphere
in the arterial and usually in the venous phase. The delayed scan abnormality was increased activity, often
faint, over the affected hemisphere.

~om the Department of Radiology, Division of Nuclear Medicine, Martin Luther King, Jr. General Hospital, and the Charles R. Drew Pos~­
graduate Medical School, Los Angeles County, Los Angeles, Calif. Accepted for publication in June 1975. An additional article related to this
subjectwill be found on page 87.
dk
113

114

JEFFREY S. STEVENS AND FRED S. MISHKIN

October1975

Fig. 1. Initial radionuclide cerebral anqloqram during seizures shows increased activity in the right cerebral cortex during the arterial phase
(A). The venous phase (B) is normal.
Fig. 2. Initial delayed images during seizures demonstrate increased activity in the right cerebral cortex on the anterior (A), posterior (B),
and vertex (E) views.
Fig. 3. Twelve days later the radionuclide cerebral angiogram is normal, except for early appearance of nasopharyngeal activity.
Fig. 4. Normal delayed images twelve days later.
Fig. p. Three months later the radionuclide cerebral angiogram remains normal.
Fig. 6. A focal area of increased activity (arrow) high in the right parietal region can be seen on the delayed images three months later on
the anterior {A), posterior (B), right lateral (C) and vertex (E) views.

OISCUSSION

In the case presented, a lesion, evident on the elec-

troencephalogram but initially too small to be detected
on the brain scan, caused abnormalities on the radionuelide cerebral angiogram and scan as a result of seizure

ABNORMAL CEREBRAL ANGIOGRAMS AND SCANS DUE TO SEIZURES

Vol. 117

Table I:
Patient

Radionuclide Delayed
Angiogram
Scan

Nuclear
Medicine

Correlation of Brain Scan Results and Clinical Data

I nterval from
Last Seizure

Description of Seizure

1
2
3
4
5
6
7
8

+
+
0
+
+
+
+
+

0
0
+
0
+
+
+
+

1 day
<1 day
6 days
<1 day
< 1 day
<1 day
<1 day
2 days

Single focal
Multiple focal
Two general ized
Single generalized
Multiple generalized
Single focal
Single focal
Single generalized

9
10
12
13
14

+
+
+
+
+
+

0
+
+
+
0
0

1 day
3 days
3 days
<1 day
3 days
1 day

Poorly described
Multiple generalized
Multiple generalized
Multiple focal
r Two poorly described
Single generalized

15
16*
17
18
19
20
21
22

+
+
0
0
0
0
0
0

0
+
0
0
0
0
0
0

3 days
0
8 days
7 days
1 day
4 days
2 days
2 days

Status epilepticus
Multiple focal
Single generalized
Single generalized
Single general ized
Single generalized
Single generalized
Multiple generalized

11

115

Follow-up Interval With No
Neurologic Deficit
16 mo.
13 mo.
No follow-up
1 mo.
6 mo.
10 mo.
3 mo.
3 mo. Died: aortic endocarditis
and infarction of opposite
hem isphere.
2 mo.
No follow-up
23 mo.
4 mo.
6 mo.
3 mo. Died: ruptured spleen.
Brain normal.
No follow-up
See text
20 mo.
No follow-up
22 mo.
17 mo.
30 mo.
1 mo.

* = The reported case. 0 = normal; + = abnormal.
activity it induced. These abnormalities resolved when
the seizures ceased. When it reached a sufficient size,
the lesion itself was delineated ona subsequent brain
scan and contrast cerebral angiogram. None of the additional 21 cases presented in TABLE I showed a focal
neurologic deficit at the time of study and all but 4 had
additional follow-up interviews indicating no neurologic
abnormality.
Our data suggest that if seizures occur within 6 days
of brain scanning, the scan is likely to be abnormal. This
is in contrast to the generally normal findings in patients
with a history of a seizure disorder but no recent seizures. If the history of recent seizure activity is not
known, the abnormal study can be easily misinterpreted. In 12 of the 16 abnormal studies, we suggested
a variety of possible etiologies other than seizures.
, The radionuclide angiographic finding of relative increase in perfusion to metabolically active cortex correlates with studies noting marked increases in brainblood flow and oxygen consumption in animals with induced seizures (5). The cause for the widespread cortical abnormality on delayed brain scan images remains
uncertain but may be related to the increased metabolic
demand of the actively discharging cortex which cannot
be met by the increased blood flow.

REFERENCES
1. McAfee JG, Fueger GF: The values and limitations of scintillation scanning in the diagnosis of intracranial tumors. [In] Scintillation Scanning in Clinical Medicine, by JL Quinn III. Philadelphia, Saunders, 1964, pp 183-317
2. Mishkin FS, Mealey J Jr: Use and Interpretation of the Brain
Scan. Springfield, 111., Thomas, 1969, pp 169-171

Fig. 7. A lateral view from a right common carotid artery
injection shows a 2.5 cm diameter vascular mass high in the
right parietal region.

3. Prensky AL, Swisher CN, DeVivo DC: Positive brain scans in
children with idiopathic focal epileptic seizures. Neurology 23:798807, Aug 1973
4. Holmquest DL, Launey WS Jr: Abnormal scintiangiographic
findings associated with seizure activity. Radiology 111: 147-150,
Apr 1974
5. Plum F: Metabolic characteristics of brain tissue. [In] Central Nervous System Investigation with Radionuclides, by AJ Gilson,
WM Smoak III. Springfield, III.,Thomas, 1971, pp 5-17
Department of Radiology
Division of Nuclear Medicine
Martin Luther King, Jr. General Hospital
12021 South Wilmington Avenue
Los An~eles, Calif. 90059