The Dutch Linguistic Intraoperative Protocol: A valid linguistic approach to awake brain surgery

Abstract

Intraoperative direct electrical stimulation (DES) is increasingly used in patients operated on for tumours in eloquent areas. Although a positive impact of DES on postoperative linguistic outcome is generally advocated, information about the neurolinguistic methods applied in awake surgery is scarce. We developed for the first time a standardised Dutch linguistic test battery (measuring phonology, semantics, syntax) to reliably identify the critical language zones in detail. A normative study was carried out in a control group of 250 native Dutch-speaking healthy adults. In addition, the clinical application of the Dutch Linguistic Intraoperative Protocol (DuLIP) was demonstrated by means of anatomo-functional models and five case studies. A set of DuLIP tests was selected for each patient depending on the tumour location and degree of linguistic impairment. DuLIP is a valid test battery for pre-, intraoperative and postoperative language testing and facilitates intraoperative mapping of eloquent language regions that are variably located.

The verb and noun test for peri-operative testing (VAN-POP): standardized language tests for navigated transcranial magnetic stimulation and direct electrical stimulation

“…Since the task requires many linguistics processes simultaneously, more error types can appear under stimulation for verbs than for nouns: grammatical errors of failed inflection of person, number, or tense can appear. Action naming in sentence context, therefore, is a straightforward tool and as easy to administer as object naming [14,33]. Moreover, by including grammatical factors, it allows testing the patient's language skills more thoroughly than an object naming task alone.…”

“…These lines of reasoning have led to the development of various tests for intraoperative testing with DES. The Dutch Linguistic Intraoperative Protocol (DuLIP; [14]), for example, offers a wide range of tasks including both noun and verb retrieval which can be selected based on the patient's characteristics. Whereas some intraoperative batteries such as the aforementioned DuLIP entail action naming tasks, these paradigms were designed to fit the time window of DES, lasting for up to 4 s [13].…”

Language neuroplasticity in brain tumour patients revealed by magnetoencephalography

“…Brain tumour surgery aims to prolong survival by removing pathological tissue, while avoiding deficits (H. Duffau, 2007). This approach requires the use of tests that are sensitive enough to capture subtle impairment (Brownsett et al, 2019;De Witte et al, 2015; see also Rofes & Miceli, 2014;Sierpowska et al, 2017). Protocols often make use of standard neuropsychological tests, which are sensitive to impairments in the moderate to severe range, such as those seen in stroke-induced aphasia.…”

Changes in language white matter tract microarchitecture associated with cognitive deficits in patients with presumed low-grade glioma

“…It seems to be involved in several cognitive functions, such as language (semantics and reading), 10 but also attention and visual processing abilities. 5,7 The UF is an association bundle that connects the orbitofrontal cortex with the anterior temporal lobe and is suggested to be involved in memory and language. 24 Quantitative information on WM tract microarchitecture can be derived from tractography and expressed as fractional anisotropy (FA) and mean diffusivity (MD).…”