Cranial Fossa, PosteriorMutismInfratentorial NeoplasmsPneumocephalusNeurosurgical ProceduresDandy-Walker SyndromeCranial Fossa, MiddleCerebellar NeoplasmsArnold-Chiari MalformationFourth VentricleCerebellar DiseasesCerebellopontine AngleSyringomyeliaCranial Fossa, AnteriorArachnoid CystsCisterna MagnaMagnetic Resonance ImagingEpendymomaTrigeminal NeuralgiaCraniotomyMedulloblastomaDermoid CystHematoma, Epidural, CranialCerebral VentriculographyOccipital BoneCerebellumTomography, X-Ray ComputedPostoperative ComplicationsArachnoidForamen MagnumHydrocephalusDura MaterPlatybasiaHematoma, SubduralSkull NeoplasmsDecompression, SurgicalTrephiningCerebral Ventricle NeoplasmsKlippel-Feil SyndromeMeningiomaNeurocutaneous SyndromesMeningeal NeoplasmsPterygopalatine FossaMeningoceleBrain DiseasesTreatment OutcomeSpasmEpidermal CystRetrospective StudiesSkullEncephaloceleSkull Base NeoplasmsTrigeminal NerveVentriculostomyIntracranial Arteriovenous MalformationsBrain NeoplasmsCerebellar AtaxiaFacial MusclesNerve Compression SyndromesTrigeminal Nerve DiseasesCerebral AngiographyCerebral VeinsHemangioblastomaSkull Fractures