Unsuspected Neurologic Disease in

Aviation Personnel:

A, Survival Following Seizures in Flight —IT

Joun H. Sewex, Pu.D., M.D. and Axtuur E. Wentz, M.D.

Te PROBLEM of the early detection of neuro-
logical disease in aviation personnel is serious
because of the possibility of the sudden and catastroph-
ic incapacity that may result from such disease. The
problem of seizures while at the controls during flight
is probably more common than might be suspected; the
following case illustrates such incapacity and one rel-
atively common etiology of seizures.

REPORT OF CASE

Case #A4M-130-707:—This 34 year old white single applicant
for a first class airman’s certificate was referred to this facility for
neurological consultation regarding an unexplained loss of
consciousness. He was examined on June 18, 1962.

CHIEF COMPLAINT:—None.

INFORMANT:-—The informant was the subject who was alert,
cooperative, well oriented in all spheres, and apparently reliable.

His memory for the episode and its constellation of circum-
stances was only partially complete and was somewhat less so
than would be expected considering its potential impact on his
future, There was no attempt to withhold information apparent
to the examiner.

PRESENT ILLNESS:—In 1946 the airman suffered a skull
fracture in an automobile accident and was unconscious for 24
hours. The site of the fracture is unknown to him. On regaining
consciousness he was amnestic for the episode; his memory
cleared completely in several days. He was hospitalized for sev-
eral months and was symptom-free for the entire period. Records
from the hospital at which he was treated were unavailable. He
had brief orthostatic hypotension for 1-2 years following the
skull fracture and subsequently worked as a steeple jack for 4-5
years without incident.

‘The subject had generally been eating and sleeping very little
for some months prior to his episode; the previous day being in
no way different from the previous many. He slept several hours
during that day and remained awake continuously during the
succeeding time, flying as co-pilot on a night flight leaving Og-
den, Utah on December 7, 1961. The flight was delayed in
Cheyenne and again in Denver. On the approach and final run of
the trip’s termination in Topeka, Kansas, he noted nothing unusual
until he regained consciousness on the landing roll; according to
his pilot he had been out for approximately 20 minutes. There

Dr. Seipel is a Senior Aviation Medical Examiner #4542-08-5
and Chief, Neurology Branch, Georgetown Clinical Research In-
stitute, AM-130, Federal Aviation Agency, Washington, D. C.

Dr. Wentz is Director, Georgetown Clinical Research In-
stitute, AM-130, Federal Aviation Agency, Washington, D. C.

was no aura of any sort; he had been functioning well. As related
by the pilot, he was sitting up looking straight ahead, made no
response when spoken to, slumped to the right side of his seat,
and struck his head injuring his nose. He made no sound or noise;
a slight jerking motion of his left side was seen. His pilot was
unable to assist him and neither attempted to awaken him or to
check his condition as he had to land the plane alone. There was
no incontinence; the applicant bit the left side of his tongue
during the episode. On awakening he felt “hazy” but was neither
tired, “washed out,” nor weak, and had no headache. He began
the usual checks; his pilot took over the paperwork because the
airman’s writing was illegible. He was able to converse co-
herently, The next day he flew back with the airline chief pilot
and did well.

He was hospitalized later in December for a complete neuro-
logical evaluation. Following its completion, he was placed on
Dilantin therapy, 100 milligrams three times a day, and has
remained seizure-free on this medication. He has had no prior
or {ubsequent similar episodes and no history of seizures as a
child.

PAST HISTORY:—Non-contributory..

GENERAL PHYSICAL EXAMINATION:—Within normal
limits.

NEUROLOGICAL EXAMINATION:—On neurological exam-
ination he was a slim, well-developed, well-nourished, right-
handed white male in no distress. The neurological examination
was entirely unremarkable except for air conduction hearing
equaling bone conduction hearing on the left, two-point dis-
crimination of 9 millimeters on the right and 17 millimeters
on the left, and the minor memory deficit previously noted.

LABORATORY: 7

URINALYSIS: Normal

BLOOD: Normal

CHEMISTRY: Serum Cholesterol—400 mg. per cent, Fast-
ing Blood Sugar—112 mg. per cent.

ELECTROCARDIOGRAM: Normal

DOUBLE MASTER: Normal

VISION: Normal

HEARING: Normal in left ear. 35 db. loss @ 2 KC. in right
ear.

RADIOLOGICAL:

Skull:--Within normal limits with no evidence of old frac-
ture, The films from his neurological work-up were avail-
able and were reviewed.

Carotid Arteriograms:—Films were late phase and showed
little detail of the major vessels. There was good filling to
the inner table on the left. No injection on the right was
performed.

Pneumoencephalogram:—Films were excellent (Figure 1).
There was no cortical air and the ventricles were well
outlined. In all projections the right ventricle was sym-
metrically larger than the left. No shift was seen.

ELECTROENCEPHALOGRAPHY:—A fairly adequate tacing

Reprinted from Aerospace Medicine, Vol. 34, No. 8, August 1963





UNSUSPECTED NEUROLOGIC DISEASE IN AVIATION PERSONNEL-SEIPEL AND WENTZ

nations referred to the chief senses, such as unusual
sounds, foul smells or tastes, unusual lights or scotomata,
and sudden strangeness of familiar surroundings or its
reverse. As patients will frequently not volunteer such
information for fear they might be thought to be men-
tally deranged such points should he specifically and
sympathetically questioned.

2. Sudden and abrupt loss of consciousness rather
than the relatively slower “blacking-out” seen in syn-
cope;

3. Evidence of self-injury, such as tongue biting, head
injuries, and bruises and lacerations on the body;

4, Urinary or fecal incontinence;

5. Post-episodic confusion, generalized or focal motor
weakness, headache, and tiredness; and

6. Evidence of convulsive movements or inappropri-
ate activity as noted by persons who may have wit-
nessed the episode.

Should one or more of the previous be positive, in par-
ticular those of aura, self-injury, incontinence, convulsive
movements, and post-ictal symptoms, the patient can be
safely presumed to have had a seizure, whether any
evidence of abnormality is found on neurological exami-
nation or not. If the patient is an airman he should be
grounded immediately until complete studies have been
obtained; in the interests of his own safety and that of
the public it is better to err on the side of conservatism
rather than risk recurrence at a time when injury or
fatality might result.

Despite a detailed history and examination, if the
physician is not certain that the patient has had a sei-
zure the patient can be told that all unexplained epi-
sodes of unconsciousness are potentially serious, that
having occurred once they are likely to occur again

without warning and at any time, and that he should -

not place himself in any situation, including driving a
car and flying, where a recurrence might endanger him-

self or others. When a definite diagnosis has been ,

established, the patient should be told he has seizures
and his prognosis discussed. The word epilepsy, be-
cause of its adverse social and legal connotations, should
not be mentioned under any circumstance. If directly

questioned regarding epilepsy, unless he has a true.
idiopathic convulsive disorder the patient should be :

told he has a symptomatic convulsive disorder sec-
ondary to scar tissue, or whatever etiology, and that he
does not have true “epilepsy.”

It is not the purpose of this presentation to review

the diagnosis and treatment of convulsive disorders; '

such information can be found in many standard text-
books. However, it should be noted that if the physician
does not have complete familiarity in this field the
patient should be referred to a neurologist for definitive
studies and treatment if there is even a slight suspicion
that a seizure may have occurred; had he been so re-
ferred, this patient might have been spared many years
of uncertainty and distress.

Aerospace Medicine + June 1963


UNSUSPECTED NEUROLOGIC DISEASE IN AVIATION PERSONNEL-SEIPEL AND WENTZ

Fig, 1. Pneumoencephalogram showing slight right ventricular
enlargement.

was obtained despite much movement artifact. The basic alpha
rhythm wae 10 per second; the record was poorly organized in all
leads with evidence of diffuse dysrythmia. An asymmetry of
amplitude was noted with higher voltage activity present on the
left in all leads; slowing to 4 per second was seen frequently on
the left; frequent spikes were present in the left temporal leads
and occasionally in the right temporal leads. High voltage bursts
of irregular slow activity were occasionally seen in the left in
all leads but were more marked in the temporal leads. Hyper-
ventilation produced a further disorganization in all leads, par-
ticularly on the right, with build-up of high voltage activity and
increased spiking bilaterally; 2 per second slowing was also ap-
parent in all leads. The record was interpreted to show general-
ized abnormality compatible with a convulsive disorder and
sgeneralized cerebral atrophy more marked on the right.

IMPRESSION:—It_was the impression of the examiner that
this airman bad suffered a grand mal seizure having a right
cortical focal component; the underlying etiologic pathology was
most probably diffuse cortical and subcortical atrophy and. scar-
ring secondary to the cerebral trauma sustained during and after
the 1946 auto accident.

SUBSEQUENT COURSE:—The airman was subsequently
denied certification by the Civil Air Surgeon’s Medical Review
Board; he then appealed to the Civil Aeronautics Board,

As he was unable to present expert medical testimony to in-
dicate a diagnosis other than seizure his appeal was dismissed.

Since the neurologist he had most recently consulted indicated
that the likelihood of another seizure was remote, it was ex-
plained to the airman that he could present his case in appeal
to the Administrator's Medical Advisory Panel for exemption to
the regulations; he was unaware of this possibility.

COMMENTS

In this case the history of abrupt loss of conscious-
ness, the observed jerking of the left side, the tongue
biting, and the postictal partial incapacity were diag-

nostic of seizure; the electroencephalogram supported
the diagnosis and indicated a generalized cerebral ab-
normality. The subsequent pneumoencephalogram gave
evidence of cerebral atrophy; and the past history gave
a presumptive etiology.

Since the airman was actually in control of the plane
when his seizure occurred it was fortunate that his
pilot was able to assume control before an accident
could occur. Had the episode taken place during land-
ing a short while later the outcome might have been
entirely different.

He was quickly and adequately studied; anticonvul-
sant therapy was promptly instituted. The medication
and a change in his living habits to include sufficient
sleep and food have resulted in his remaining seizure-
free to the present.

DISCUSSION

In the absence of a history of infantile or childhood
sei.ures, seizures of late onset occurring for the first
time after the adolescent age range (in which idio-
pathic convulsive disorders are likely to occur) must
be considered as pathognomonic of brain tumor be-
cause of the potential seriousness of this disease; such
patients must be studied promptly and intensively to
rule out this possibility and to determine the correct
etiology where possible. Anticonvulsants should be
started as soon as it has been determined that a seizure
has occurred; their use will not interfere with the sub-
sequent studies. This case history illustrates excellently
such an evaluation and demonstrates a frequent path-
ologic etiology for seizures.

Most commonly no etiology will be found following
a thorough study; space-occupying lesions frequently
are initially sufficiently small that no observable ab-
normality can be seen on arteriography or pneumoen-
cephalography. With time the expansion of the lesion
continues and localizing neurological changes will de-
velop; eventually, sufficient evidence can be amassed to
enable surgical exploration. For this reason these pa-
tients should be carefully followed to permit definitive
therapy as early as possible.

A Frequent etiology of seizures is the intemperate
use of alcohol, the so-called “alkalepsy.” Since patients
will rarely admit alcoholism and may exhibit few or
none of the obvious findings of the disease, the physician
is faced with the usual problem of suspicion but no
proof, Discussion of the patient's habits with his family
and associates is often helpful; the physician should
be careful not to give offense by suggesting his suspi-
cions and should mention the subject only as a part of
his general inquiry into the patient’s background.

As illustrated by the preceding case, a not infrequent
finding is cortical and subcortical atrophy. Such pa-
thology can arise from many causes such as trauma,
vascular impairment, exposure to toxins, and sometimes
apparently without .determinable etiology. It is not
certain at present whether atrophy, per se, can give
rise to seizures or if the atrophy reflects underlying
pathology, such as scarring, which gives rise to the
seizures; in most cases the observed atrophy appears
to be a part of the general brain reaction to insult of

Aerospace Medicine + August 1963


Unsuspected Neurologic Disease in
Aviation Personnel:

Survival Following Seizures in Flight

Joun H. Sewer, Px.D., M.D., and Arrnur E. Wentz, M.D.

Reprinted from Aerospace Medicine, Vol. 34, No. 8, August 1963



UNSUSPECTED NEUROLOGIC DISEASE IN AVIATION PERSONNEL-SEIPEL AND WENTZ

one form or another. In the preceding case the electro-
encephalogram indicated that the airman suffered dif-
fuse cortical traumatic damage with subsequent scar-
ring and atrophy; the focal component of his seizure
and the more apparent atrophy of the right cortex in-
dicated that damage on this side was more marked
than on the left.

Even should a plausible etiology be determined in
a particular patient it should be emphasized that brain
tumors can occur in alcoholics and persons who have
suffered previous neurological disease. While all seizure
patients should be followed at frequent intervals to
tule out this remote possibility the major reason for
close supervision is that the physician is thus made
available for counseling and support. The patient who
is suffering from a convulsive disorder is faced with
an often shattering problem of reaching an understand-
ing of his disease and its ramifications which often re-
quire far-reaching readjustments in his way of life.

A further point illustrated by this case is Federal
Aviation Agency practice in cases in which medical
certification is questioned, After denial at the Regional
level the applicant has the right to request review by the
Civil Air Surgeon’s Medical Review Board. This Board
of Agency consultants will then review the medical
evidence and request further information where nec-

Aerospace Medicine » August- 1963

essary; the airman is given the opportunity of examina-
tion at the Georgetown Clinical Research Institute at
no expense to him other than his transportation to
Washington, food, and lodging. If, in the Board’s opin-
ion, the cause for denial is not supported by the evi-
dence or if there is no standard that would preclude
the safe exercise of privileges by the airman, certifica-
tion is issued. If again denied, the airman has two alter-
natives; he can appeal to the Administrator for an ex-
emption from the regulations or he can appeal directly
to the Civil Aeronautics Board. Since the Medical Re-
view Board and the Civil Aeronautics Board are bound
by the regulations regarding certification, if a non-
certifiable medical diagnosis has been established, cer-
tification cannot be granted by either body. The only
group empowered to recommend to the Administrator
that an exemption to the regulations be granted is the
Administrator’s Medical Advisory Panel. This panel is
composed of outstanding senior consultants in the vari-
ous specialties chosen from the entire country who con-
sider each case individually. If, in their opinion, the
airman’s disease is stable and he can safely exercise
the privileges of his certificate without danger to him-
self or to the public, an exemption may be granted by
the Administrator and certification may be issued.

GPO 882-972





UNSUSPECTED NEUROLOGIC DISEASE IN AVIATION PERSONNEL-SEIPEL AND WENTZ

Unsuspected Neurologic Disease in Aviation Personnel:

A. Survival Following Seizures in Flight—I

Joun H. Sere, PD. M.D., and Arraur E. Wentz, M.D.

‘HE INCREASING USE of private and commer-

cial air transportation combined with the steady in-
crease in recreational aviation have inevitably increased
the likelihood of pilot failure caused by medical dis-
ability simply because there are more pilots in the air
more frequently. Thus, the problem of the early de-
tection of disease likely to cause incapacity without
warning has become serious.

Parallel to its research into the physiology of aging,
the Georgetown Clinical Research Institute has ex-
amined a large number of applicants who. had been
denied certification at the regional level and who were
referred in consultation to determine as precisely as
possible their medical status prior to disposition of their

Dr. Seipel is Senior Aviation Medical Examiner #4542-08-5,
Chief, Neurology Branch, Georgetown Clinical Research In-
stitute, AM-130, Federal Aviation Agency, Washington 25, D. C.

Dr. Wentz is Director, Georgetown Clinical Research In-
stitute, AM-130, Federal Aviation Agency, Washington 25, D, C.

applications by higher authority. These airmen have
been studied extensively, as is routine for applicants
examined in the Institute; additional other studies have
been performed in depth where indicated to clarify
the status of their diseases and to give baselines for
future comparison.

As members of the Institute and consultants to the
Federal Aviation Agency in neurology, the authors have
examined a large number of airmen who have neu-
rological problems bearing on aviation medical certifi-
cation. Many of these case histories dramatically illus-
trate important facets of neurological disease and its
management; these histories also illustrate that much
disease of the nervous system is being overlooked by
Aviation Medical Examiners and other physicians who
have had occasion to see these airmen. Since pre-
existing neurological disease is particularly prone to
cause sudden and catastrophic incapacity without warn-
ing,-we are presenting a series of these histories as case
reports to indicate the importance of the early and

Reprinted from Aerospace Medicine, Vol. 34, No. 6, June 1963