SUMMARY

A Kuwaiti woman of 47 years came to hospital after being involved in a road traffic accident fully conscious but complaining of headache. She had no obvious head injury. Clinically there was no neurological deficits, skull radiography was normal and hence was discharged home after a period of observation. Twenty four hours later she was admitted to hospital with impaired consciousness, dilated right pupil and right spastic hemiparesis. CT scan of the brain showed right fronto-parietotemporal mass with shift of the brain to the opposite side. At emergency craniotomy extensive subdural haematoma was found and evacuated and a bleeding cortical artery in the sylvian fissure coagulated. She made a rapid, uneventful recovery after craniotomy, and she remained neurologically normal during follow-up.

RESUME

Une femme Koweitienne de 47 ans a ete hospitalisee apres un accident de la voie publique. Elle n’a pas eu de perte de canescence mais se plaignait de cephalees. Elle ne presentait pas de blessure evidente a la tete. Cliniquiment, il n’y avait pas de deficit neurologique. La radio du crane etait normale, elle rentra donc chez elle apres une periode d’observation; 24 beures apres, elle etait hospitalisee avec une dimunution de la conscience, une mydriase droite et une hemiparesie droite spastique. Le scanner cerebral a montre une masse fronto-parietotemporale droite avec deplacement du cerveau du cote oppose. Une trepanation faite en urgence a permis d’evacuer un hematome sous-dural etendu et de coaguler une artere corticale sylvienne qui saignait. Le retablissement de la patiente a ete rapide apres la trepanation, et l’examen neurologique normal pendant toute la duree du suivi.

Keywords : Subdural haematoma, Arterial origin

INTRODUCTION

Although subdural haematoma is usually of venous origin, it is known that it can sometimes result from arterial rupture occurring in association with an aneurysmal or arteriovenous malformation (1,6), neoplastic lesions on the dura (8), infection, vitamin C deficiency, alcohol abuse and coagulopathy (3). Rarely, the arterial rupture may be spontaneous when it occurs in the absence of obvious head trauma and of the above predisposing and risk factors.

Whatever the aetiology, the literature review of acute subdural haematoma (ASH) of arterial origin has shown it to be attended by an unusually high mortality of about 50 per cent (12) due to delay in diagnosis and institution of appropriate surgical treatment. We present a case in this paper in which early diagnosis and prompt correct neurosurgical intervention led to a successful outcome.

CASE REPORT

S.F., a 47 year old Kuwaiti woman, the mother of seven children, was involved in a road traffic accident on January 31, 1990. The car she was driving overturned over after bursting a tyre and she was thrown against the steering wheel. She did not lose consciousness. She come to the Casualty Department of Al-Adan Hospital, Kuwait complaining of headache. On physical examination, she was correctly oriented and cooperative; there was no head wound and the neurological system was clinically normal. Skull and chest radiograms obtained were normal. She was kept under observation in the Casualty Department for four hours after which she was allowed to go home because she remained clinically stable.

On February 1, 1990, about 24 hours after discharge, an ambulance brought her back to the Medical Section of the Casualty Department of Al-Adan Hospital on the suspicion that she had suffered a stroke because she was drowsy. After leaving hospital on January 31, 1990, her headache had worsened especially on the right side, accompanied by vomiting, unsteadiness of gait and slurring of her speech. On examination by the receiving physician, She was described as drowsy with a Glasgow coma score of 10, right facial palsy of upper motor neurone type and right spastic hemiparesis. The scalp was normal, her pulse rate was 56 per minute and the blood pressure 160/110 mm Hg. She was admitted to the Medical Ward of the hospital with the diagnosis of cerebrovascular accident, with the differential diagnosis of subdural haematoma.

An electrocardiogram showed sinus bradycardia and an emergency CT scan of the brain revealed a large right fronto-parieto-temporal mass with marked shift of the brain to the left side. Neurosurgical consultation was immediately sought.

Within one hour of admission, she rapidly passed from a drowsy state into coma with the right pupil dilated but slowly reacting to light. She was intubated and put on controlled ventilation in preparation for emergency neurosurgical operation.

At operation, no scalp wound was found. A right parietal burr hole showed no extradural haematoma but a blue bulging non-pulsatile dura indicating subdural haematoma. A fronto-parieto-temporal craniotomy was performed. When the dura was opened. an extensive fronto-parieto-temporal subdural haematoma which had partially clotted was revealed; it was peeled off and removed completely to show normal looking brain. At the bottom of the wound, close to the skull base, a slowly bleeding cortical artery was found; the vessel was easily coagulated and the bleeding arrested.

The patient made a remarkable good and uneventful postoperative recovery. She come off the ventilator on February 3 and soon regained full consciousness. She moved all her limbs satisfactorily and the right pupil became normal. She was transferred from the Intensive Care Unit to the Surgical Female Ward on February 4 and discharged from hospital on February 11, 1990. She complained of dizziness and had elevated blood pressure which necessitated treatment with methyldopa. She had been known to have arterial hypertension for about a year before her accident but had been on irregular treatment.

She was last seen in Neurosurgery Clinic on June 19, 1990, doing well and neurologically normal. She was booked to attend the Clinic again by the middle of August 1990. She could not keep that appointment with the Iraqi invasion in Kuwait on August 2, 1990.

DISCUSSION

Acute subdural haematoma (ASH) of arterial origin is probably not as rare as formerly thought (3, 14) and the features appear uniform enough to make it a distinctive entity of its own. The patients are middle-aged to elderly. The bleeding artery is seen at operation close to the base of the skull in the region of the Sylvian fissure and the brain is grossly normal. CT scan shows that the brain shift is often considerable such that it produces ipsilateral hemiparesis, the Kernohan’s phenomenon (5).

All these features were present in our patient. The Kernohan’s phenomenon was common in the cases reported by Tokoro et al (14). Indeed, Talalla and McKissock (13) had suggested that the phenomenon is a sign of ASH of arterial origin; unrelieved the shift caused by the rapid increase in the size of the haematoma can precipitate quick deterioration in the level of consciousness and even death.

ASH of arterial origin can easily be confused with cerebrovascular accident, as was our case and those reported in the literature (12, 13) Tokoro et al (14) labelled it an unusual form of cerebrovascular accident. This seems appropriate since the bleeding in the cases reported came from the cortical branches of the middle cerebral artery. This is an anatomical territory of arterial junction where strains and stresses, which can be precipitated by mild or unobserved head trauma can cause arterial rupture and bleeding.

Two factors which predispose to arterial bleeding into the subdural space in our case are head injury and arterial hypertension. Although she had no obvious head wound and skull radiography was normal, head trauma cannot be totally excluded in our case. Drake (2) had postulated that in the so called spontaneous variety of ASH of arterial origin, head trauma is involved but it may be minor and mild and pass unnoticed. Shenkin (11) found arterial bleeding in over 60 percent of his 39 patients with traumatic subdural haematoma.

Arterial hypertension was present in about 45 per cent of cases of ASH of arterial origin described in the literature (7,14). Subdural haematoma has been observed to be commoner in hypertensives than in normotensive individuals (9).

Delay in instituting neurosurgical treatment can be fatal as shown by case 3 of Stephenson and Gibson (12) and accounts for the high mortality associated with this disease. On the other hand, prompt neurosurgical evacuation of the haematoma is very rewarding with the survivor gaining a life with little or no neurological deficits (3).

Simple burr hole is not enough to remove the subdural clotted blood and control the arterial bleeding. Jamieson and Yelland (4) advised that once the subdural haematoma had been detected through a burr hole, the latter should be converted to a craniotomy, as we did in our case. A craniotomy is essential not only to completely evacuate the large thick and extensive haematoma but also to facilitate the arrest of the arterial bleeding. The procedure makes for adequate intracranial decompression and a good early post operative recovery.