Comparative analysis of parenchymal and extraparenchymal neurocysticercosis: a 10-year experience from northern Thailand

Neurocysticercosis (NCC) is a leading cause of epilepsy and neurological morbidity in endemic regions. This study compares clinical characteristics, treatment, and outcomes between parenchymal and extraparenchymal NCC in northern Thailand. A retrospective cohort of 106 adult NCC patients (2015–2024) was reviewed at Chiang Mai University. Patients were categorized based on neuroimaging. Clinical data, treatment regimens, and functional outcomes (using modified Rankin Scale) were assessed at baseline, discharge, and 3, 6, and 12 months. Of 106 patients, 84 (79.2%) had parenchymal and 22 (20.8%) had extraparenchymal NCC. Seizures were more common in parenchymal cases, while sensory deficits and hydrocephalus predominated in extraparenchymal cases. Surgical intervention was significantly more frequent in extraparenchymal NCC (86.4% vs. 4.8%, P < 0.001). Despite overall improvement, extraparenchymal cases had worse outcomes at all time points. Corticosteroids did not improve long-term function and were linked to more adverse events. Parenchymal and extraparenchymal NCC have distinct clinical patterns and outcomes. Extraparenchymal NCC is more severe, frequently requiring surgery and resulting in greater disability. Corticosteroid use showed no association with long-term outcomes, highlighting the need for early diagnosis and tailored treatment strategies. Parenchymal and extraparenchymal NCC differ in presentation and outcomes. Extraparenchymal NCC shows more severity and often requires surgery. Corticosteroids showed no clear long-term benefit in this cohort. Early diagnosis and tailored care are key in endemic, limited-resource areas.