Third cranial nerve paresis at the Emergency Department – reviewing a clinical case

Abstract

Third cranial nerve paresis, although uncommon, is a clinical
situation with a broad differential diagnosis which may be associated with severe disease, particularly intracranial aneurysms,
with high morbidity and mortality.
The authors present the case of a 40-years-old woman admitted at the Emergency Department with headache, diplopia and
right palpebral ptosis for the last fortnight. Furthermore, the patient
mentioned impaired coordination of voluntary movements for the
last year, with an acute confusional episode about 2 months earlier.
Regarding her personal history she was a smoker, light alcohol
habits, light tricuspid insufficiency and had been submitted to
hysterectomy for cervical dysplasia. There was a history of recent
right acute otitis media, as well as a homolateral dental abscess.
On physical examination, there was right palpebral ptosis, light
anisocoria, binocular diplopia, abolished right direct and consensual photomotor reflexes, adiadochokinesis and light dysmetria at
the finger-nose test, particularly with the left superior extremity.
As the head CT scan was normal, the patient was admitted to
the Internal Medicine Department in order to clarify the clinical frame.
On the 3rd day of admission, she mentioned worsening of the
headache, another CE CT-scan was carried out, with intravenous
contrast showing subarachnoid hemorrhage. 3D reconstruction
displayed an aneurysm on the right posterior communicating artery.
The authors discuss the diagnostic approach used in this
particular case, as well as the correct approach (according to
literature) in a situation of third cranial nerve paresis.