P06.08.B VALIDATION OF THE DIGITAL DIAGNOSTIC INSTRUMENT FOR MILD APHASIA IN PATIENTS WITH GLIOMAS: PRELIMINARY RESULTS

Abstract BACKGROUND Patients with gliomas frequently show subtle language disturbances (mild aphasia). There is a lack of sensitive tests leading to negative effects on quality of life. Therefore, the digital Diagnostic Instrument for Mild Aphasia (DIMA) was developed. DIMA examines the most important linguistic levels: phonology, semantics and (morpho)-syntaxis on both language production and comprehension. We aim to validate DIMA in a preliminary group of patients. MATERIAL AND METHODS Patients with gliomas underwent awake surgery due to tumor location in eloquent areas. They were tested as part of standard care on two moments: preoperatively (T0) and 2-3 months (T1) postoperatively with DIMA (mean age 48.38, sd 14.64). Patients were matched according to test moment, age and education with 42 healthy Dutch-speaking participants (mean age 45.43, sd 17.38). All patients were compared to healthy participants, using an independent samples t-test. Patients’ mean z-scores were computed for all DIMA subtests (z-score ≤-1.5 = clinical impairment, clinical change = difference z-score 1.5). Reaction times were computed for T0 and T1. RESULTS At T0 (N=21), no significant differences on DIMA performance were found between patients and healthy controls, apart from a trend on one subtest: total sentence judgment (p=.069). However, patients were slower than healthy controls on the sentence completion task (p<0.05). A clinical impairment was found on repetition of compound words (phonology) (z=-2.19). At T1 (N=13), a significant difference was found between patients and healthy controls (p<0.05) on repetition of sentences (phonology). A clinical improvement on repetition of compound words was found (T0: z= -2.19 - T1: z=-0.19) compared to preoperative level. CONCLUSION Digital DIMA appeared to be sensitive in a preliminary patient group with gliomas. Pre- and postoperative language impairments were found on phonological subtests of DIMA. Awake surgery seemed to have protected language functions until short-term postoperatively. Instead, a clinical improvement was found on repetition of compound words, underlining the value of intraoperative monitoring of word repetition. In addition, patients deviated on reaction times on one subtest which has already been found to be sensitive and important for the rate of return to work. We will further examine the long-term language outcome at 1 year, influence of demographic and clinical variables on performance in a larger dataset of glioma patients and in other neurological patient groups. We advise adding the DIMA to standard perioperative language evaluation of glioma patients, as it allows for more detailed baseline investigation before awake surgery and counseling about language recovery. Digitalization of tests such as DIMA is crucial for international uniform standard care and research to investigate outcome.