Validation of a prediction model for long-term outcome of aphasia after stroke

Neuromodulation of the Right Motor Cortex of the Lips With Repetitive Transcranial Magnetic Stimulation to Reduce Phonological Impairment and Improve Naming in Three Persons With Aphasia: A Single-Case Experimental Design

PURPOSE

Repetitive transcranial magnetic stimulation (rTMS) can enhance aphasia recovery. Most studies have used inhibitory stimulation targeting the right inferior frontal gyrus. However, the motor cortex, observed to contribute to the prediction of aphasia recovery, is involved in word production and could be an appropriate target for rTMS. We aimed to observe behavioral changes in a picture naming task induced by inhibitory rTMS targeting the right motor cortex of the lips in people with poststroke aphasia.

METHOD

Using a single-case experimental design, we included three participants with chronic poststroke aphasia who had phonological deficits. Each participant performed a verbal picture naming task 3 times a week for 2, 3, or 4 weeks (pseudorandom across participants) to establish a baseline naming ability for each participant. These were not therapy sessions, and no feedback was provided. Then, each participant received the intervention, inhibitory continuous theta burst stimulation targeting the right motor cortex of the lips, 3 times a week for 2 weeks. Naming testing continued 3 times a week, for these latter 2 weeks. No therapy was performed at any time during the study.

RESULTS

Visual analysis of the graphs showed a positive effect of rTMS for P2 and P3 on picture naming accuracy and a tendency toward improvement for P1. Statistical analysis showed an improvement after rTMS for P1 (τ = 0.544, p = .013, SETau = 0.288) and P2 (τ = 0.708, p = .001, SETau = 0.235). For P3, even if the intervention allowed some improvement, this was statistically nonsignificant due to a learning effect during the baseline naming testing, which lasted the longest, 4 weeks. Regarding specific language features, phonological errors significantly decreased in all patients.

CONCLUSIONS

The motor cortex of the lips could be an appropriate target for rTMS to improve naming in people with poststroke aphasia suffering from a phonological deficit. This suggests the possibility to individualize the target for rTMS, according to the patient's linguistic impairment.

The clinical and neurocognitive functional changes with awake brain mapping for gliomas invading eloquent areas: Institutional experience and the utility of The Montreal Cognitive Assessment

Objective

Awake craniotomy with intraoperative brain functional mapping effectively reduces the potential risk of neurological deficits in patients with glioma invading the eloquent areas. However, glioma patients frequently present with impaired neurocognitive function. The present study aimed to investigate the neurocognitive and functional outcomes of glioma patients after awake brain mapping and assess the experience of a tertiary neurosurgical center in China over eight years.

Methods

This retrospective study included 80 patients who underwent awake brain mapping for gliomas invading the eloquent cortex between January 2013 and December 2021. Clinical and surgical factors, such as the extent of resection (EOR), perioperative Karnofsky Performance Score (KPS), progression-free survival (PFS), and overall survival (OS), were evaluated. We also used the Montreal Cognitive Assessment (MoCA) to assess the neurocognitive status changes.

Results

The most frequently observed location of glioma was the frontal lobe (33/80, 41.25%), whereas the tumor primarily invaded the language-related cortex (36/80, 45%). Most patients had supratotal resection (11/80, 13.75%) and total resection (45/80, 56.25%). The median PFS was 43.2 months, and the median OS was 48.9 months in our cohort. The transient (less than seven days) neurological deficit rate was 17.5%, whereas the rate of persistent deficit (lasting for three months) was 15%. At three months of follow-up, most patients (72/80, 90%) had KPS scores > 80. Meanwhile, compared to the preoperative baseline tests, the changes in MoCA scores presented significant improvements at discharge and three months follow-up tests.

Conclusion

Awake brain mapping is a feasible and safe method for treating glioma invading the eloquent cortex, with the benefit of minimizing neurological deficits, increasing EOR, and extending survival time. The results of MoCA test indicated that brain mapping plays a critical role in preserving neurocognitive function during tumor resection.

Lesion Distribution and Early Changes of Right Hemisphere in Chinese Patients With Post-stroke Aphasia

The role of the right hemisphere (RH) in post-stroke aphasia (PSA) has not been completely understood. In general, the language alterations in PSA are normally evaluated from the perspective of the language processing models developed from Western languages such as English. However, the successful application of the models for assessing Chinese-language functions in patients with PSA has not been reported. In this study, the features of specific language-related lesion distribution and early variations of structure in RH in Chinese patients with PSA were investigated. Forty-two aphasic patients (female: 13, male: 29, mean age: 58 ± 12 years) with left hemisphere (LH) injury between 1 and 6 months after stroke were included. The morphological characteristics, both at the levels of gray matter (GM) and white matter (WM), were quantified by 3T multiparametric brain MRI. The Fridriksson et al.’s dual-stream model was used to compare language-related lesion regions. Voxel-based lesion-symptom mapping (VLSM) analysis has been performed. Our results showed that lesions in the precentral, superior frontal, middle frontal, and postcentral gyri were responsible for both the production and comprehension dysfunction of Chinese patients with PSA and were quite different from the lesions described by using the dual-stream model of Fridriksson et al. Furthermore, gray matter volume (GMV) was found significantly decreased in RH, and WM integrity was disturbed in RH after LH injury in Chinese patients with PSA. The different lesion patterns between Chinese patients with PSA and English-speaking patients with PSA may indicate that the dual-stream model of Fridriksson et al. is not suitable for the assessment of Chinese-language functions in Chinese patients with PSA in subacute phase of recovery. Moreover, decreased structural integrity in RH was found in Chinese patients with PSA.

Deep Learning Approach Using Diffusion-Weighted Imaging to Estimate the Severity of Aphasia in Stroke Patients

BACKGROUND AND PURPOSE

This study aimed to investigate the applicability of deep learning (DL) model using diffusion-weighted imaging (DWI) data to predict the severity of aphasia at an early stage in acute stroke patients.

METHODS

We retrospectively analyzed consecutive patients with aphasia caused by acute ischemic stroke in the left middle cerebral artery territory, who visited Asan Medical Center between 2011 and 2013. To implement the DL model to predict the severity of post-stroke aphasia, we designed a deep feed-forward network and utilized the lesion occupying ratio from DWI data and established clinical variables to estimate the aphasia quotient (AQ) score (range, 0 to 100) of the Korean version of the Western Aphasia Battery. To evaluate the performance of the DL model, we analyzed Cohen's weighted kappa with linear weights for the categorized AQ score (0-25, very severe; 26-50, severe; 51-75, moderate; ≥76, mild) and Pearson's correlation coefficient for continuous values.

RESULTS

We identified 225 post-stroke aphasia patients, of whom 176 were included and analyzed. For the categorized AQ score, Cohen's weighted kappa coefficient was 0.59 (95% confidence interval [CI], 0.42 to 0.76; P<0.001). For continuous AQ score, the correlation coefficient between true AQ scores and model-estimated values was 0.72 (95% CI, 0.55 to 0.83; P<0.001).

CONCLUSIONS

DL approaches using DWI data may be feasible and useful for estimating the severity of aphasia in the early stage of stroke.

Surgical Strategies and Clinical Outcome of Large to Giant Sphenoid Wing Meningiomas: A Case Series Study

Large to giant sphenoid wing meningiomas (SWMs) remain surgically challenging due to frequent vascular encasement and a tendency for tumoral invasion of the cavernous sinus and optic canal. We aimed to study the quality of resection, postoperative clinical evolution, and recurrence rate of large SWMs. This retrospective study enrolled 21 patients who underwent surgery between January 2014 and December 2019 for SWMs > 5 cm in diameter (average 6.3 cm). Tumor association with cerebral edema, extension into the cavernous sinus or optic canal, degree of encasement of the major intracranial arteries, and tumor resection grade were recorded. Cognitive decline was the most common symptom (65% of patients), followed by visual decline (52%). Infiltration of the cavernous sinus and optical canal were identified in five and six patients, respectively. Varying degrees of arterial encasement were seen. Gross total resection was achieved in 67% of patients. Long-term follow-up revealed improvement in 17 patients (81%), deterioration in two patients (9.5%), and one death (4.7%) directly related to the surgical procedure. Seven patients displayed postoperative tumor progression and two required reintervention 3 years post initial surgery. Tumor size, vascular encasement, and skull base invasion mean that, despite technological advancements, surgical results are dependent on surgical strategy and skill. Appropriate microsurgical techniques can adequately solve arterial encasement but tumor progression remains an issue.