Test administration pre-operative

In this video, I will show you how a tailor-made language test is developed for an individual patient. I will show you how tests are selected based on the results of the pre-operative linguistic and neuropsychological assessment, and the characteristics of the tumour as seen on the pre-operative functional and structural MRI scan. In our center, our pre-operative assessment consists of standardised measures such as semantic and phonological fluency. We use a naming test to assess word finding difficulties, and another task, the shortened token test for auditory language comprehension. Besides detection of language deficits, we create a baseline for intraoperative task selection and follow up language assessments using the DuLIP.

Moreover, we perform an extensive neuropsychological assessment consisting of tests from the following cognitive domains– memory, attention, processing speed, executive functions, and social cognition. Besides tests, we assess mood, subjective complaints, personality, and coping with standardised questionnaires. Now let’s see how we can apply this to our patient. He’s a 31-year-old male, adopted when he was two weeks old from Sri Lanka. He followed more than 30 years of education and works full time in a warehouse of a camera wholesale. He’s right handed. Since December 2014, he’s had episodes of confused language. And he received psychological treatment for anxiety and obsessive compulsive disorder, although not very successfully.

In retrospective, he has had 10 years of progressive word finding difficulties, memory complaints, mental slowness, and fatigue. Pre-operative scans of his brain, structural MRI, shows a large left temporal insular tumour, suspect for a low grade glioma.

Here you see more preoperative scans of his brain. Functional MRI images during picture naming on the left and verb generation, similar to action naming, on the right. These images show that the tumour itself doesn’t contain language function. We can also derive from these images that the left hemisphere is dominant for language function in this right handed patient.

Pre-operative assessment of language using DuLIP showed no impairments on the overall sound level of phonology in various repetition tasks. Surprisingly, he failed at a phoneme deletion task where he had to delete a sound from a word and then produce the new word. However, this task also taps working memory. Some mistakes were made at the level of semantics within the semantic picture out nouns and verbs task. Object naming showed some word finding difficulties and semantic paraphasias. These items were excluded from the intraoperative naming set. Action naming showed some semantic and some phonological paraphasias. Therefore, these items were excluded from the intraoperative action naming set.

As explained earlier, we can use only those items that were named correctly pre-operatively in order to interpret errors intraoperatively. Based on the tumour location, namely left temporal left insular, and based on the preoperative neuropsychological assessment and the language assessment, several tasks were selected from the DuLIP protocol– for instance, object naming and action naming. This is a 3D DTI tractography with the tumour shown and the arcuate fasciculus.

This image is constructed by the neuroradiologist, or the neurosurgeon to consider the best approach for tumour resection. This is also discussed together with the clinical linguist. It is expected that at a later stage of the resection, the neurosurgeon will approach the arcuate fasciculus. By stimulating the arcuate fasciculus, it is expected that the patient will make some mistakes at repetition of words, while spontaneous speech, naming, and comprehension remain intact. Based on the DTI, it was expected that at the subcortical level, we would approach the arcuate fasciculus. So therefore, we chose to administer repetition of words intraoperatively.