| Epidemiological data |
Age (defined as age at surgery) |
| Gender (defined as biological gender) |
| Medical history |
Hypertension (defined as documented diagnosis or intake of antihypertensive medication) |
| Diabetes mellitus (defined as documented diagnosis of type 1 or 2 diabetes or intake of oral antidiabetics or insulin) |
| Hyperlipidemia (defined as documented diagnosis or intakt of medication lowering the lipid or cholesterol levels in the blood) |
| Peripheral arterial disease (defined as documented diagnosis or imaging finding) |
| Heart disease (defined as documented diagnosis of myocardial infarction, coronary artery disease, cardia arrhytmia or other heart diseases) |
| Ischaemic stroke (defined as documented diagnosis or imaging finding at admission) |
| Thrombosis (defined as documented diagnosis) |
| Malignant tumor disease (defined as documented diagnosis regardless of affected organ) |
| Autoimmune disease (defined as documented diagnosis with need of immunosuppressive therapy) |
| Obesity (defined as a documented body mass index of > 30 kg/m2) |
| Nicotine abuse (defined as ex-nicotine abuse or continued nicotine abuse) |
| Alcohol abuse (defined ot consumption of > 50 g of alcohol per week) |
| Contraceptive use and intake of hormone replacement products (at time of diagnosis, extracted from medical records or medication plans) |
| CT-imaging parameters |
Type of bleeding, shifting of the midline, intraventricular hemorrhage, hydrocephalus and ischaemia (all assed in the first CT-scan after SAH) |
| Aneurysm-related parameters |
Rupturestatus (defined by assessment of intraoperative findings, imaging findings and bleeding patterns in CT) |
| Multiplicity (defined as > / = 2 intracranial aneurysms) |
| Aneurysm localization (defined by assessment of angiography) |
| Clinical scores |
Glasgow coma scale at admission and discharge (defined by neurological examination at admission and discharge) |
| Modified rankin scale at discharge (defined by neurological examination at discharge) |
| Hunt and Hess grade, WFNS score and Fisher grade at admission (defined by neurological examination at admission and imaging findings) |
| Treatment-related parameters |
Previous and current treatment and treatment-modality (extracted from medical records) |
| Surgery-related parameters |
Number of clips used (extracted from the operation report) |
| Type of craniotomy (extracted from the operation report) |
| Occurence of intraoperative rupture (extracted from the operation report) |
| Need for and duration of intraoperative temporary clipping (extracted from the operation report) |
| Use of intraoperative indocyanine green angiography and/or microvascular doppler sonography (extracted from the operation report) |
| Need for primary or secondary decompressive hemicraniectomy (extracted from the operation report) |
| Occurence and type of postoperative stroke or haemorrhage (extracted from the postoperative CT-scans) |
| Degree of occlusion of the aneurysm and need for revision in partially/unoccluded aneurysms (extracted from the postoperative angiography and medical records) |
| Complication-related parameters |
Hydrocephalus, placement of an external ventricular drainage or ventriculoperitoneal shunt (extracted from medical records) |
| Vasospasm, method of vasospasm-detection and treatment via endovascular spasmolysis (extracted from medical records) |
| Follow-up data |
Time of follow-up, perfusion of the aneurysm and modified rankin scale at follow-up (extracted from medical records) |
