Postcraniotomy headache could be bothersome problem for both patients underwent brain surgery and surgeons performing the surgery [1]. Even if surgical procedure itself conducted properly, a patient might feel discomfort if there was postoperative headache that was not existed before surgery [3]. The authors performed prospective randomized controlled trial comparing effect of scalp nerve blocks (SNB) before scalp incision to conventional management in aspect of better recovery from craniotomy in 52 patients who underwent clipping of unruptured intracranial aneurysm [2]. The authors included factors associated with postoperative recovery, including the quality of recovery (QoR)-40 score, pain scale, opioid consumption, and postoperative nausea and vomiting.

They reported that QoR-40 score was not significantly different between the SNB and control groups but small differences in one and two days after surgery. On the other hands, postoperative pain scale within 3-12 hours after surgery and total amount of opioid consumption less than 3 hours were significantly less severe in the SNB group. It seems like that small number of patients might affect these subtle differences between the SNB and control groups. As addressed in discussion section, the authors also know that sample size included in this study is too small for a certain conclusion. However, it is noteworthy that postoperative pain score and opioid consumption were significantly lowered in spite of this small sample size.

Chronic subdural hematoma is one of the most common disorders that neurosurgeons encounter in clinical conditions [5,8]. Even though a delayed hemorrhage hypothesis following previous minor trauma is a well-known mechanism of chronic subdural hematoma, there are many chronic subdural hematoma without reliable causes including previous trauma history [8]. In cases without any exact causes, burr-hole trephination with indwelling drainage catheter is a widely accepted treatment strategy for chronic subdural hematoma [5]. Because use of antithrombotic agent might be one of probable cause of chronic subdural hematoma, discontinuation of such a medicine that used to be prescribed for prevention of cerebrovascular and cardiovascular diseases could be an important issue especially for old age patients [7].

The authors retrospectively review medical records of 462 patients who underwent burr-hole trephination for chronic subdural hematoma [4]. They reported that intake history of antithrombotic agents did not significantly increase risks of recurrences of chronic subdural hematoma and reoperations after initial burr-hole drainage. Moreover, there was no statistical correlation between use of antithrombotic agents and increases of morbidity and mortality. Based on these observations, the authors concluded that maintenance of antithrombotic aged might be recommended for patient with chronic subdural hematoma considering the burr-hole drainage surgery. Analyzing surgical outcome in aspect of evidence based medicine is not an easy work especially for such an emergency based operation [7]. It is considered that retrospective cohort study with multicenter medical records might be the most feasible alternatives to overcome such a limitation.

The author also reviewed thromboembolic complication related to use of antithrombotic agents and chronic subdural hematoma. They found that most study emphasized early resumption of antithrombotic agents after surgical intervention for chronic subdural hematoma. Because cardiovascular disease is the major cause of death for old age [6], the author argued that continuous use of antithrombotic agent is recommended for prevention of averse cardiovascular events after surgical intervention.