Study design and setting
Potentially eligible patients were identified using the International Classification of Disease – 10 (ICD-10) diagnosis of all types of intracranial abscesses (i.e. SDE, IPA, EDA) under the umbrella code of “intracranial abscess and granuloma” (G06.0) between 1st January 2000 and 31st December 2020. Medical records of the individual subjects were manually screened and only patients with the sinogenic intracranial abscesses were included in the study. A preliminary report on the outcomes of the first 14 patients have been previously reported by our group[16].