T2 relaxometry helps prognosticate seizure outcome in patients with solitary cerebral cysticercosis Aaron de Souza a, ⁎, Atchayaram Nalini a , Jitender Saini b , Kandavel Thennarasu c a Department of Neurology, National Institute of Mental Health and NeuroSciences, Bangalore 560 029, India b Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and NeuroSciences, Bangalore 560 029, India c Department of Biostatistics, National Institute of Mental Health and NeuroSciences, Bangalore 560 029, India abstract article info Article history: Received 16 January 2017 Received in revised form 17 February 2017 Accepted 23 February 2017 Available online 27 February 2017 Objective: Correlate serial T2 relaxometry (T2R) values with long term seizure outcome in patients with solitary cerebral cysticercosis (SCC) in order to establish its usefulness as a prognostic marker in these patients. Methods: Patients with new-onset seizures due to SCC were imaged serially using a pre-determined MRI protocol at enrolment and after 3, 6, 12 and 24 months. T2 relaxometry was performed using a dual echo sequence with maps generated manually from the measured image intensities at the level of the lesion. Patients were randomised to receive albendazole plus antiepileptic drugs, or only antiepileptic treatment (“controls”). At each visit, as well as four years after study initiation, patients were reviewed for seizure recurrence. Clinical and radiological outcomes were assessed by physicians blinded to treatment received. Results: Of 123 patients recruited, 77 had at least four MRIs and N 12 month follow-up, and were included for anal- ysis. Baseline clinical and demographic parameters as well as antiepileptic treatment were similar between albendazole and control groups. T2 values from the lesion were higher than normal parenchyma initially, and fell to approach normal over six months. Controls had higher T2 values from the lesion centre and wall at six months than those who received albendazole. However no difference was seen in T2 values from perilesional pa- renchyma between treatment and control groups, indicating lack of modulation of the development of perilesional gliosis by albendazole therapy. Patients with seizures persisting N 6 months after enrolment had higher perilesional T2 values than those who were seizure-free. A rise in perilesional T2 value at 12 months is probably due to gliosis. A later stage of degeneration was associated with a reduced likelihood of seizure relapse. Significance: T2 relaxometry at three and six months after seizure onset can identify patients likely to have sei- zures beyond six months after onset. Persistently abnormal T2 values in patients with poorer outcomes reflect the development of perilesional gliosis. © 2017 Elsevier B.V. All rights reserved. Keywords: Cysticercosis Brain Epilepsy Gliosis T2 relaxometry 1. Introduction Seizures can complicate parasitic infections of the central nervous system and may develop both as an acute-phase response as well as long-term sequelae [1]. Neurocysticercosis (NC) is an important reason why epilepsy and seizures are more frequent in developing countries: [2] seizures are thought to be related to this parasite in as many as 30% of adult patients in endemic areas [3–6] and in 51% of children [7]. Those seizures occurring in the context of a degenerating cyst with oedema may be considered acute symptomatic seizures while those patients with seizures after oedema resolution and resorption or calcification of the cyst have true chronic epilepsy [8]. We have previ- ously shown that as many as 88.3% of patients with solitary cerebral cysticercosis (SCC), the commonest form of the disease in India, were seizure-free one year after onset of their seizures, but that the remain- der continued to have recurrent seizures despite antiepileptic drug treatment [9]. Although persistence of the lesion beyond one year after onset of seizures indicates a poorer outcome from epilepsy due to SCC [9], conventional MRI is not useful to assess therapeutic response [10] and better markers are needed in order to tailor antiepileptic drug therapy in such patients. Advanced MRI techniques such as magnetization transfer imaging (MTI) have previously been used by us and others to identify signal change presumably correlating with gliosis around the SCC lesion. This imaging finding is useful in prognosticating seizure outcome, the num- ber of seizures as well as the risk of seizure recurrence being higher in patients with visible gliosis [10–17]. We have recently shown that T2 relaxometry (T2R) also helps delineate presumed gliosis within the SCC as well as in the perilesional parenchyma [18]. This technique has been previously found to be useful for the identification and analysis Journal of the Neurological Sciences 376 (2017) 1–6 ⁎ Corresponding author at: Department of Neurology, Goa Medical College, Bambolim, Goa 403202, India. E-mail address: adesouza1@gmail.com (A. de Souza). http://dx.doi.org/10.1016/j.jns.2017.02.052 0022-510X/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns