Name:
10.3171/2024.10.FOCVID24101
Description:
10.3171/2024.10.FOCVID24101
Thumbnail URL:
https://cadmoremediastorage.blob.core.windows.net/2fca73cf-69b4-417e-b876-098f7ed6c0e4/videoscrubberimages/Scrubber_318.jpg
Duration:
T00H10M28S
Embed URL:
https://stream.cadmore.media/player/2fca73cf-69b4-417e-b876-098f7ed6c0e4
Content URL:
https://cadmoreoriginalmedia.blob.core.windows.net/2fca73cf-69b4-417e-b876-098f7ed6c0e4/3. 24-101.mp4?sv=2019-02-02&sr=c&sig=KNL5Y7AJwgRY2prbuXyc1qEc%2BNadzhtF8WmAqMSuXH4%3D&st=2026-02-21T04%3A01%3A35Z&se=2026-02-21T06%3A06%3A35Z&sp=r
Upload Date:
2024-11-21T00:00:00.0000000
Transcript:
Language: EN.
Segment:0 .
[MUSIC PLAYING]
SPEAKER: Brain mapping for lower-grade glioma around Wernicke's area. The anatomical boundaries of Wernicke's area are not clearly defined in the literature. Generally, it is located in part of the inferior parietal lobule and the posterior part of the superior and middle temporal gyrus. Wernicke's area is theoretically connected with the arcuate fasciculus. For precise mapping and safe preservation during surgery, both anatomical and functional identification are useful.
SPEAKER: Originally, Wernicke's area refers specifically to a region in the dominant hemisphere involved in complex language processing, mainly comprehension. In the nondominant hemisphere, the homologous area is responsible for spatial awareness and the concept of body image. Deficits in this area on the nondominant side can cause spatial neglect syndrome. Wernicke's area is surrounded by several eloquent areas, and any damage can lead to complications.
SPEAKER: These include sensory disturbances from the sensory cortex anteriorly, symptoms of Gerstmann's syndrome from the inferior parietal lobule, language disturbances from Wernicke's area itself, and auditory disturbances from Heschl's gyrus, several related subcortical white matter tracts, such as the arcuate fasciculus as a part of the dorsal stream of language function. Symptoms of aphasia could occur if the arcuate fasciculus is damaged, especially conductive aphasia.
SPEAKER: The superior longitudinal fasciculus and the sagittal stratum, which is the group of multiple white matter tracts locate at the lateral wall of the atrium, are also crucial. Preserving these structures during surgery near Wernicke's area is both critical and challenging. We present a case of a 48-year-old female truck driver with a history of a first episode seizure.
SPEAKER: Her neurological and cognitive examinations were normal. MRI FLAIR imaging revealed a hyperintense lesion in Wernicke's area on the left supramarginal and angular gyrus, invading part of the superior parietal lobule. There was no T2 FLAIR mismatch or contrast enhancement on the MRI, and no calcification on CT. Based on this data, the preoperative diagnosis was astrocytoma grade 2 with a differential diagnosis of oligodendroglioma grade 2.
SPEAKER: For surgical consideration, we must balance the extent of resection with the risk of neurological deficits due to possible injury to Wernicke's area and surrounding aforementioned structures. The type of tumor also influences our strategy, as oligodendroglioma grade 2 responds well to chemotherapy and radiation, unlike astrocytoma, which shows only moderate response to radiation and limited evidence of chemotherapy efficacy.
SPEAKER: Additionally, her occupation as a truck driver requires specific functions, such as an intact visual field. Deficits like homonymous hemianopia or sensory disturbances could hinder her ability to work. For these reasons, we plan a safe maximal resection under awake craniotomy, monitoring language and visual fields to prevent homonymous hemianopia and preserving sensory function and Gerstmann syndrome. We plan several brain mapping tasks, including dual task, which examined picture naming and motor function for monitoring arcuate fasciculus.
SPEAKER: Additionally, repetition, word generation, and free talk are planned to monitor this tract. Any level of speech disturbance, including anomia, dysphagia, aphasia, or even dysarthria was documented, ensuring we did not go beyond the boundary. Pyramid and palm tree tests for semantic paraphasia for monitoring inferior frontal occipital fasciculus for screen tests for visual field defects as the function of optic radiation, sensory disturbance monitoring for somatosensory cortex and tracts.
SPEAKER: Finally, calculation for one-digit and two-digit results, left-right disorientation, finger agnosia, and writing to monitor Gerstmann syndrome. We use bipolar stimulation to ensure precise stimulation in both cortical and subcortical mapping with an amplitude of 4 mA, a pulse duration of 0.5 msec,, and a pulse rate of 50 Hz. If residual tumor was clearly present, we considered lowering the amplitude to 2 mA to facilitate more radical tumor removal.
SPEAKER: The patient was placed in the lateral position, with her head rotated approximately 90 degrees to the contralateral side and fixed with a Mayfield head holder. Wide craniotomy and dural incision were performed at the lesion site. Cortical mapping was conducted to ensure safe corticotomy. Incorrect calculations in this area led us to choose a different gyrus for corticotomy.
SPEAKER: After confirming negative mapping, safe tumor debulking was performed. Free talk was useful during the operation.
SPEAKER: Cortical mapping was repeated at the supramarginal gyrus. After confirming negative stimulation, the resection was safely continued. Repetition was also checked.
SPEAKER: We checked her sensation on the posterior side of the postcentral sulcus. Due to anomia, we would not resect beyond this point.
SPEAKER: Now we were close to the optic radiation. The tumor around here was relatively harder. She saw some abnormal light, which indicated the stimulation to the optic radiation. Therefore, this area was the limit of resection.
SPEAKER: Postoperative MRI showed the tumor was partially removed. The remnant was found in the superior parietal lobule and the inferior side of the optic radiation. The pathological diagnosis was astrocytoma grade 2, IDH-mutant with intact 1p19q, MGMT-methylated, no homozygous deletion of CDKN2A, and no TERT promoter mutation. Immediately postoperative, the patient showed anomia, phonemic paraphasia, repetition disturbance, comprehension deficit, and severe Gerstmann syndrome.
SPEAKER: Two weeks after surgery, word generation was still deficit, and there were minor repetition issues. Her paraphasia nearly resolved. Acalculia persisted, and finger agnosia nearly resolved. At the 6-month follow-up, she had right inferior quadrantanopia. The standard language test of aphasia showed deficits in word comprehension and calculation. The Revised Hasegawa's Dementia Scale was normal.
SPEAKER: And the Mini-Mental State Examination scored 29. Her Wechsler Memory Scale and Wechsler Adult Intelligence Scale showed minimal decline compared to preoperative status. In conclusion, surgery for lower-grade glioma around Wernicke's area is challenging due to potential neurological deficits, including language deficits, visual field defects, sensory disturbances, and Gerstmann syndrome. Awake craniotomy and brain mapping are essential for surgery in this area, as illustrated by our case. Balancing tumor resection extent with the risk of potential injury is crucial.
Form Title Download
Form Title Bookmark
Form Title Share
Form Title Cite
