|Year : 1987 | Volume
| Issue : 1 | Page : 4-6
Ocular manifestations of internal carotid artery insufficiency
Rajiv Nath, MK Mehra, D Nag, J Agarwal
King George's Medical College, Lucknow, India
King George's Medical College, Lucknow
Source of Support: None, Conflict of Interest: None
8 cases of internal carotid artery insufficiency were studied to find out the various ophthalmic manifestations in such cases. 50% cases had ophthalmic signs and symptoms. These manifestations were amaurosis fugax, central retinal artery block, field defects, pupillary abnormalities and disc oedema. Ammaurosis fugax is a sign of impending carotid insufficiency and these cases must be investigated thoroughly.
|How to cite this article:|
Nath R, Mehra M K, Nag D, Agarwal J. Ocular manifestations of internal carotid artery insufficiency. Indian J Ophthalmol 1987;35:4-6
The branches of Internal Carotid Artery supply a large part of the visual pathways along with the Eye. Occlusion of this artery or its intracranial branches can cause significant ophthalmological manifestations, which can be very diverse, ranging from monocular blindness to a case without any manifestations. These symptoms and signs often get manifest before the onset of neurological signs and symptoms. That is why, an analysis of ocular symptoms reflecting the disorders of the carotid system is of great importance in the early diagnosis and treatment of these disorders and, therefore, this neuro-ophthalmological study has been undertaken.
| Material and method|| |
This study was undertaken in collaboration with the Neurology Department. It consists of 8 patients of Internal Carotid Artery insufficiency, admitted to King George's Medical College and Hospital, Lucknow. All cases were of less than 12 weeks duration (so - that possibility of collateral circulation was remote). They were subjected to a detailed history taking, examination, fundus examination, field charting and investigations (Angiographic study was done, if indicated). The angiographic studies are usually contraindicated in fresh cases.
The cases of Internal Carotid Artery insufficiency were diagnosed on the basis of their neurological presentation (contra-lateral Hemiplegia/Hemiparesis, Hemiphypesthesia, sometimes with Aphasia and behavioral symptoms) and presence of bruit in the Internal Carotid Artery at the angle of jaw, 'and diminished pulsations of Carotid as compared to the other side.
Remaining 4 cases (case Nos.1, 3, 4 and 7) had no ophthalmic manifestation.
| Observation and discussion|| |
Ophthalmic signs and symptoms were found to be present in 4 patients (50% cases) out of 8 cases in all. This is quite comparable to previous studies of Johnson & Walker (1951) (40%) and Babel & Psilas (1973) (45%).
The type of manifestation found is quite clear from [Table - 1]. Visual loss was seen in 3 cases. Two of these had a history of recurrent intermittent loss of vision (Amaurosis Fugax) at intervals of few months before the onset of Hemiplegia. These were unilateral, present in the eye contralateral to the side of Hemiplegia and lasted for few minutes only (about 5 minutes). These patients did not have any cardiac disease to account for any embolic phenomenon. They had a normal visual acuity at the time of examination. Amaurosis Fugax is considered as a very alarming symptom by neurologists as well as ophthalmologists because it is a heralding sign of Internal Carotid block. There was no accompanying dizziness or light headiness and there was no constant precipitating factor. Third patient (No.8) had a complete and permanent visual failure (No PL in that eye) and had a Fundus picture of classical Central Retinal Artery block. How the other two cases escaped a permanent visual loss, is explained on the basis of stealing blood from opposite internal carotid circulation (through Circle of Willis). However, this could not be proved by angiography because the latter is not done in fresh cases. The belief that such cases are helped by collaterals is proved by the escape of some cases of therapeutic ligation of Internal Carotid Artery or its branches from its hazardous effects.
Visual field defects also constituted an important finding. They were present in 2 out of 6 cases. where it could be done. The deficit found was a lower homonymous quadrantanopia. There was no other change. It could not be done in 2 cases because of low visual acuity due to cataract in one case, and a marked behavioural change in the other case (due to involvement of anterior cerebral artery territory also).
Ipsilateral mydriasis with absence of a direct reaction but retention of consensual reaction (Marcus Gun Phenomenon Positive) was present in case No.8 which had central retinal artery block as described above.
Disc oedema was present in the left eye of case No.2 (a young boy who also had right sided homonymous quadrantanopia). There was no locally explanable cause. The visual acuity was 6/9. The cause of this could be a minimal optic nerve head ischaemia.
| References|| |
Babel J. & Psilas K.: Ophthalmologica. 1973, 167: 273-287.
Fischer M.: Arch. Ophth. 1952, 47: 167-203.
Hollenhorst R.W. : Med. Clin. North. Am. 1960, 44 : 897.
Miller S.J.H. : Trans. Ophth. Soc. U.K., 1960, 80 : 287 - 299.
[Table - 1]