Chronic subdural hematoma is a common neurosurgical problem in old age, because most of these patients are fragile geriatric group; the least invasive technique is preferred. Burr hole craniostomy is considered the gold standard for surgical treatment of chronic subdural hematoma [17, 9, 14].
Our aim is to minimize the surgical manipulations and anesthetic agents and to enhance recovery with minimal complications and reduce recurrence rate.
In general, for patients who have coexisting complex systemic disease, local anesthesia is a more favored method during surgery for CSDH [18, 19].
Many reports from different studies noted the safety of both general and local anesthesia in chronic subdural hematoma with minor complications [16, 19,20,21].
Moreover, general anesthesia may alter the return to preoperative levels of consciousness after such procedures which need to be evaluated early postoperatively to exclude the need for redo due to early postoperative recollection [6].
Local anesthesia was used during endoscopic removal of clotted blood and in multilocular hematomas in fragile patients [22]. It was used by many other authors and Khadka et al. [23], Lee et al. [21], and Yadav et al. [2].
In our study, the mean age was 60 years old, and this is explained in most studies due to the known pathologic changes in this age group [2].
Our study showed male predominance 56.7%, it was 71.8% males in the series of Mori and Maeda [16] and 66.3% in Ernestus et al. [15]. The predominance of male sex was due to the more vulnerability for trauma.
Regarding the location of CSDH, the left side was the most commonly affected in our study and in most other studies, 52% in Mori and Maeda [16]. The explanation may be the more convex skull on the left side in most people [24].
Clinical features develop over a period of days to weeks. Sometimes, patients fail to recall events of head injury. The common predisposing factors are head injury, alcoholism, seizure disorders, brain atrophy, anticoagulation, and impaired surgical hemostasis. Head injury was evident in 64.2% of our patients. It is usually a trivial trauma [2].
Clinically, patient may present with headache, nausea, hemiparesis, vomiting, sensory deficit, language disturbance, gait problems, transient ischemic symptoms, convulsions, decreased level of consciousness, and raised intra cranial pressure. In our study, the clinical presentation included hemiparesis, disturbed conscious level, headache, and rarely seizures.
The most common symptom was hemiparesis followed by gait disturbance; headache was common in patients at younger ages, and this is explained by the tendency to have increased intracranial pressure at younger ages [16].
The surgical techniques used for subdural hematoma evacuation vary from twist drill craniostomy to large craniotomy procedures [20, 15]. Our choice of single burr hole instead of double burr hole was based on the assumption that unilocular CSDH could be efficiently drained and washed without the need of extra burr hole as long as it is a single fluid containing cavity.
The mean operative time was 35 min in our study, this time is equal to that of Gozel et al. [6] (36.4 min with a range from 25 to 63 min), and this is another advantage for our technique.
The number of recurrence in our study was very low, only two cases (2.98%), and this is one of the best results reported in chronic subdural hematoma surgery; the rate of recurrence after burr hole evacuation and irrigation varies between 2.7 and 34% [14, 16, 23, 25, 26].
The rate of recurrence was related to the amount of subarachnoid air in most series. Poor re-expansion of the brain is correlated to hematoma recurrence; therefore, air influx into the subdural space should be prevented during surgery [16]. Tension pneumocephalus was a dangerous complication to be prevented by filling the subdural space by normal saline, so we think that the absence of tension pneumocephalus and the lower rate of recurrence were due to the capability to fill the subdural space with saline with single burr hole than with two burr holes as there is no leak from the second burr hole during filling from the first one.
The rate of acute subdural hematoma formation was nil; this is due to the small single scalp incision and the ability to control scalp bleeding easily.
By following the patients for 6 months, the operative complications were very limited; two recurrent cases and one died after 2 weeks due to chest infection.
Two cases developed postoperative seizures, and one of them was having the convulsions preoperatively; the second one suffered the first postoperative attack 1 week postoperatively and was controlled within 1 week by anticonvulsants (IV phenytoin for 3 days followed by oral phenytoin for 2 years).
Epilepsy is traditionally thought to be a rare presentation, even though it has been reported in up to 6% of cases as an initial symptom [27].
