Background. Bone defects of the skull are observed in various pathological conditions, including head trauma and conditions requiring surgery of the skull. Independent of the consequences of the original aetiology that necessitated the craniectomy, the bone defect alone may be the cause of the symptoms, called ‘trephined syndrome’ or ‘sinking skin flap syndrome’. Despite the early recognition of neurological symptoms directly linked to craniectomy, the description of this syndrome has often relied on a small series or single clinical case reports. Objectives. To list the previously reported symptoms of SSFS. Data sources. We selected the references for this review by searching PubMed, focusing on articles published prior to June 2013 and using references from relevant articles. Study eligibility criteria. We used the following search terms: ‘trephined syndrome’, ‘syndrome of the trephined’, ‘Sinking skin flap’, and ‘sinking skin flap syndrome’. There were no language restrictions. The final reference list was generated on the basis of its relevance to the topics covered in this review. Conclusions. Clinicians need to be aware of sinking skin flap syndrome and to look for abnormal neurological developments in patients with craniectomy in order to avoid unnecessary testing and to prevent its occurrence. Accordingly, cranioplasty can be undertaken as soon as necessary.

Objective: To identify the clinical determinants of occurrence of postictal generalized EEG suppression (PGES) after generalized convulsive seizures (GCS). Methods: We reviewed the video-EEG recordings of 417 patients included in the REPO₂MSE study, a multicenter prospective cohort study of patients with drug-resistant focal epilepsy. According to ictal semiology, we classified GCS into 3 types: tonic-clonic GCS with bilateral and symmetric tonic arm extension (type 1), clonic GCS without tonic arm extension or flexion (type 2), and GCS with unilateral or asymmetric tonic arm extension or flexion (type 3). Association between PGES and person-specific or seizure-specific variables was analyzed after correction for individual effects and the varying number of seizures. Results: A total of 99 GCS in 69 patients were included. Occurrence of PGES was independently associated with GCS type (p < 0.001) and lack of early administration of oxygen (p < 0.001). Odds ratio (OR) for GCS type 1 in comparison with GCS type 2 was 66.0 (95% confidence interval [CI 5.4–801.6]). In GCS type 1, risk of PGES was significantly increased when the seizure occurred during sleep (OR 5.0, 95% CI 1.2–20.9) and when oxygen was not administered early (OR 13.4, 95% CI 3.2–55.9). Conclusion: The risk of PGES dramatically varied as a function of GCS semiologic characteristics. Whatever the type of GCS, occurrence of PGES was prevented by early administration of oxygen.