348
Injury, 6, 348-350
Transient blindness following head injuries
minor
G. M. Weisz Trauma Research Group, Department
of Surgery, Rambam Hospital, Haifa
I. Hemli Department
of Neurology,
Rambam Hospital,
Haifa
J. J. Kraus Acco Psychiatric Hospital, Israel Summary
Transient blindness following minor head injury is a rare, although well known, and totally reversible entity. As the condition may have legal implications, a Syear follow-up study was carried out on 4 young patients. Repeated ophthalmological, neurological and psychiatric examinations both early and late after injury did not reveal any organic or psychiatric diseases which might predispose to this disorder. The case reports, including one recurrent case, a follow-up study and a discussion of the aetiology are presented. DESCRIPTIONof transient blindness following minor head injury appears rarely in the neurological literature. The entity is generally found among children and is attributed to mild concussion of the visual cortex. A rapid, complete and spontaneous recovery has always been accepted as the usual result. However, we have found no long-term follow-up studies of these cases in the literature over the past 10 years. This condition has important legal and medical implications for the traumatologist. A five-year follow-up study was therefore carried out with 4 children and young adults after head injury had induced transient blindness. This was done to detect possible delayed sequelae and to discover any pathological background predisposing to this syndrome which might become clinically evident during subsequent years.
MATERIAL
AND
METHODS
Four cases were treated by us for blindness following head injury from 1967 to 1968. The
tests performed were ophthalmological : examination of the eyeball, the fundus, and the visual fields; neurological : clinical examination and electroencephalography; psychiatric: evaluation of the patient and his family. The 3-discipline study was carried out during the first 3 days after injury, after 1 month and after 5 years. The clmical details are shown in TableI and described further in the following case histories.
Case 1 A 6-year-old girl sustained a mild head injury in the occipitoparietal area, without loss of consciousness or signs of brain concussion. Following the injury, there was total loss of sight, observed initially by the parents. After 1 hour spontaneous and complete recovery occurred. Complete ophthalmic and neurological examination and a psychiatric evaluation were made and the results were within normal limits. The patient was re-examined after 1 month and after 5 years following the injury and no disturbances were found.
Case 2 A 4-year-old boy was examined after a trivial blow on the occiput followed by bilateral blindness for 2 hours. Ophthalmic and neurological examination while he was blind, followed a day later by EEG and psychiatric examination gave normal results. Complete recovery occurred. At the age of 5 the child sustained a second head injury without concussion but again with blindness for 3 hours, after which he recovered completely. The 3-discipline study made immediately after the second injury was normal. Four years later the child was perfectly healthy.
Weisz et al.
: Transient
Blindness
Table/.-Symptomatology
Case
Clinical symptoms
1
Bilateral blindness
2
2 recurrent experiences of bilateral blindness Bilateral blindness
3
349
and catamnestic data
Duration (hours) 1
Ophthalmological Vision Fundus
Examinations Neurological Clinical EEG
wnl
wnl
wnl
2 and 3
wnl
wnl
0.5
wnl
wnl
Psychiatric
Follow-up after 5 years
wnl
wnl
wnl
mild and no characteristic changes wnl
wnl
wnl
wnl
no
wnl
wnl
wnl
wnl
specific changes 4
Unilateral complete and contralateral partial blindness
2
wnl
Case 3 A 16-year-old girl was under prolonged anticonvulsive treatment because of a convulsive disorder in early childhood. On admission for a minor injury of the vertex, complete blindness was observed. After 30 minutes full recovery occurred. The patient was fully conscious and no abnormal signs were found using the 3-discipline study. On examination after 5 years, this now happily married woman and mother of one child was found to be completely healthy.
Case 4 A 24-year-old man, involved in a car accident, suffered a mild injury of the head when his occiput struck the head pad. No sign of concussion or cervical injury was found. He developed complete loss of vision in the right eye and blurred vision in the left eye lasting for 14-2 hours. Complete spontaneous recovery followed. An early 3-discipline study was carried out and repeated after 6 years, but the results were within normal limits on both occasions.
RESULTS A later study of the patients following minor head injury and complaining of blindness showed complete recovery. No sequelae were found, no maladjustment in family or social life, and no psychological disturbance was recorded. Of special interest was the patient in case 2 who sustained two similar injuries, but developed no sequelae respectively 4 and 5 years following the brief periods of blindness.
DISCUSSION During the period of blindness in all our patients we found complete loss of vision without signs of ‘ fixation ’ or ‘ optico-kinetic ’ reaction. The
wnl
wnl
no specific changes
pupillary reactions to light, the eye movements and the fundi were normal. As all re-examinations were also within normal limits the problem of causation remains to be solved. Blindness following minor head injury could be due to psychogenic reactions to trauma, injury to the eye, injury to the optic nerve or chiasma, or injury to the occipital visual cortex (Gyrus 17 in Brodmann’s classification). The defence reaction as a possible cause of blindness through a conversional mechanism can be excluded as we found no evidence in the patient’s memory of the accident having produced mental trauma. Nor, on psychiatric examination and psychological testing, were any signs of hysterical elements found in the patients’ personalities. Questioning their parents and teachers confirmed normal psychological development. Repeated ophthalmological examinations excluded direct injury to the eyeball as a possible cause of the blindness. The hypothesis of transient vascular insufficiency of the optic nerve, expounded by Bodian, is another possibility. However, we were unable to find the pupillary changes or monochromy described in the initial account (Bodian, 1964; Lancet, 1968; Greenblatt, 1973). A more likely theory is transient focal oedema of the occipital cortex as the cause of traumatic blindness after minor head injury. The theory, expounded by P&z1 (1928) was revived by Griffith and Pickles in the last 10 years (Griffith and Dodge, 1968; Pickles, 1949). This hypothesis was not based on clinical neurological findings, but only on non-specific EEG changes.
350
injury
Loss of alpha waves in the recordings is in Silverman’s view evidence in favour of cortical involvement (Silverman, 1962). Although no EEG changes were observed in our cases, the theory is accepted as the cause of transient blindness following head injury.
CONCLUSlONS Minor head injuries may induce concussion of the visual cortex, producing total or partial blindness. It is more common in children and adolescents and is completely reversible. Common characteristics in all cases are the lack of signs of organic damage to the eye, head or mental function. No disorder of any system (examined over 5 years) was found to predispose to the syndrome of transient blindness. Requests
fbr
reprints
should
be addressed
to:-G.
: the
British
Journal
of Accident
Surgery
Vol. ~/NO. 4
REFERENCES
BODIAN,M. (1964), ’ Transient loss of vision following head trauma ‘, N. Y. State J. Med., 64, 916. EDITORIAL ( 1968), ‘ Transient blindness and head injuries in children ‘, Lam-et, 2, 820. GREENBLATT,S. H. (1973), ‘ Post-traumatic transient cerebral blindness ‘, J. Am. med. Assoc., 225, 1073. GRIFFITH,J. F. and DODGE, P. R. (1968), ‘ Transient blindness following head injury in children. ’ New Engl. J. Med., 278, 648. HARRINGTON, D. 0. (1964), The Visual Louis, Mosby, p. 355.
Fields.
St
PICKLES,W. (1949), ‘ Acute focal oedema of brain in children with head injuries ‘, New Engl. J. Med., 240, 92. P~~TzL,0. (1928), Die optisch-agnostischen
Stiirungen,
Leipzig-Wien,
Deuticke, F. SILVERMAN,D. (1962), ‘ EEG study of acute injury in children ‘, Neurology, 12, 273.
M. Weisz, M.D., Department
of Surgery,
Rambarn
Hospital,
Haifa, Israel
head
Injury, 6, 348-350
Transient blindness following head injuries
minor
G. M. Weisz Trauma Research Group, Department
of Surgery, Rambam Hospital, Haifa
I. Hemli Department
of Neurology,
Rambam Hospital,
Haifa
J. J. Kraus Acco Psychiatric Hospital, Israel Summary
Transient blindness following minor head injury is a rare, although well known, and totally reversible entity. As the condition may have legal implications, a Syear follow-up study was carried out on 4 young patients. Repeated ophthalmological, neurological and psychiatric examinations both early and late after injury did not reveal any organic or psychiatric diseases which might predispose to this disorder. The case reports, including one recurrent case, a follow-up study and a discussion of the aetiology are presented. DESCRIPTIONof transient blindness following minor head injury appears rarely in the neurological literature. The entity is generally found among children and is attributed to mild concussion of the visual cortex. A rapid, complete and spontaneous recovery has always been accepted as the usual result. However, we have found no long-term follow-up studies of these cases in the literature over the past 10 years. This condition has important legal and medical implications for the traumatologist. A five-year follow-up study was therefore carried out with 4 children and young adults after head injury had induced transient blindness. This was done to detect possible delayed sequelae and to discover any pathological background predisposing to this syndrome which might become clinically evident during subsequent years.
MATERIAL
AND
METHODS
Four cases were treated by us for blindness following head injury from 1967 to 1968. The
tests performed were ophthalmological : examination of the eyeball, the fundus, and the visual fields; neurological : clinical examination and electroencephalography; psychiatric: evaluation of the patient and his family. The 3-discipline study was carried out during the first 3 days after injury, after 1 month and after 5 years. The clmical details are shown in TableI and described further in the following case histories.
Case 1 A 6-year-old girl sustained a mild head injury in the occipitoparietal area, without loss of consciousness or signs of brain concussion. Following the injury, there was total loss of sight, observed initially by the parents. After 1 hour spontaneous and complete recovery occurred. Complete ophthalmic and neurological examination and a psychiatric evaluation were made and the results were within normal limits. The patient was re-examined after 1 month and after 5 years following the injury and no disturbances were found.
Case 2 A 4-year-old boy was examined after a trivial blow on the occiput followed by bilateral blindness for 2 hours. Ophthalmic and neurological examination while he was blind, followed a day later by EEG and psychiatric examination gave normal results. Complete recovery occurred. At the age of 5 the child sustained a second head injury without concussion but again with blindness for 3 hours, after which he recovered completely. The 3-discipline study made immediately after the second injury was normal. Four years later the child was perfectly healthy.
Weisz et al.
: Transient
Blindness
Table/.-Symptomatology
Case
Clinical symptoms
1
Bilateral blindness
2
2 recurrent experiences of bilateral blindness Bilateral blindness
3
349
and catamnestic data
Duration (hours) 1
Ophthalmological Vision Fundus
Examinations Neurological Clinical EEG
wnl
wnl
wnl
2 and 3
wnl
wnl
0.5
wnl
wnl
Psychiatric
Follow-up after 5 years
wnl
wnl
wnl
mild and no characteristic changes wnl
wnl
wnl
wnl
no
wnl
wnl
wnl
wnl
specific changes 4
Unilateral complete and contralateral partial blindness
2
wnl
Case 3 A 16-year-old girl was under prolonged anticonvulsive treatment because of a convulsive disorder in early childhood. On admission for a minor injury of the vertex, complete blindness was observed. After 30 minutes full recovery occurred. The patient was fully conscious and no abnormal signs were found using the 3-discipline study. On examination after 5 years, this now happily married woman and mother of one child was found to be completely healthy.
Case 4 A 24-year-old man, involved in a car accident, suffered a mild injury of the head when his occiput struck the head pad. No sign of concussion or cervical injury was found. He developed complete loss of vision in the right eye and blurred vision in the left eye lasting for 14-2 hours. Complete spontaneous recovery followed. An early 3-discipline study was carried out and repeated after 6 years, but the results were within normal limits on both occasions.
RESULTS A later study of the patients following minor head injury and complaining of blindness showed complete recovery. No sequelae were found, no maladjustment in family or social life, and no psychological disturbance was recorded. Of special interest was the patient in case 2 who sustained two similar injuries, but developed no sequelae respectively 4 and 5 years following the brief periods of blindness.
DISCUSSION During the period of blindness in all our patients we found complete loss of vision without signs of ‘ fixation ’ or ‘ optico-kinetic ’ reaction. The
wnl
wnl
no specific changes
pupillary reactions to light, the eye movements and the fundi were normal. As all re-examinations were also within normal limits the problem of causation remains to be solved. Blindness following minor head injury could be due to psychogenic reactions to trauma, injury to the eye, injury to the optic nerve or chiasma, or injury to the occipital visual cortex (Gyrus 17 in Brodmann’s classification). The defence reaction as a possible cause of blindness through a conversional mechanism can be excluded as we found no evidence in the patient’s memory of the accident having produced mental trauma. Nor, on psychiatric examination and psychological testing, were any signs of hysterical elements found in the patients’ personalities. Questioning their parents and teachers confirmed normal psychological development. Repeated ophthalmological examinations excluded direct injury to the eyeball as a possible cause of the blindness. The hypothesis of transient vascular insufficiency of the optic nerve, expounded by Bodian, is another possibility. However, we were unable to find the pupillary changes or monochromy described in the initial account (Bodian, 1964; Lancet, 1968; Greenblatt, 1973). A more likely theory is transient focal oedema of the occipital cortex as the cause of traumatic blindness after minor head injury. The theory, expounded by P&z1 (1928) was revived by Griffith and Pickles in the last 10 years (Griffith and Dodge, 1968; Pickles, 1949). This hypothesis was not based on clinical neurological findings, but only on non-specific EEG changes.
350
injury
Loss of alpha waves in the recordings is in Silverman’s view evidence in favour of cortical involvement (Silverman, 1962). Although no EEG changes were observed in our cases, the theory is accepted as the cause of transient blindness following head injury.
CONCLUSlONS Minor head injuries may induce concussion of the visual cortex, producing total or partial blindness. It is more common in children and adolescents and is completely reversible. Common characteristics in all cases are the lack of signs of organic damage to the eye, head or mental function. No disorder of any system (examined over 5 years) was found to predispose to the syndrome of transient blindness. Requests
fbr
reprints
should
be addressed
to:-G.
: the
British
Journal
of Accident
Surgery
Vol. ~/NO. 4
REFERENCES
BODIAN,M. (1964), ’ Transient loss of vision following head trauma ‘, N. Y. State J. Med., 64, 916. EDITORIAL ( 1968), ‘ Transient blindness and head injuries in children ‘, Lam-et, 2, 820. GREENBLATT,S. H. (1973), ‘ Post-traumatic transient cerebral blindness ‘, J. Am. med. Assoc., 225, 1073. GRIFFITH,J. F. and DODGE, P. R. (1968), ‘ Transient blindness following head injury in children. ’ New Engl. J. Med., 278, 648. HARRINGTON, D. 0. (1964), The Visual Louis, Mosby, p. 355.
Fields.
St
PICKLES,W. (1949), ‘ Acute focal oedema of brain in children with head injuries ‘, New Engl. J. Med., 240, 92. P~~TzL,0. (1928), Die optisch-agnostischen
Stiirungen,
Leipzig-Wien,
Deuticke, F. SILVERMAN,D. (1962), ‘ EEG study of acute injury in children ‘, Neurology, 12, 273.
M. Weisz, M.D., Department
of Surgery,
Rambarn
Hospital,
Haifa, Israel
head
