Optimizing Motor Imagery Parameters for Robotic Arm Control by Brain-Computer Interface

Brain-Computer Interface (BCI) technology has been shown to provide new communication possibilities, conveying brain information externally. BCI-based robot control has started to play an important role, especially in medically assistive robots but not only there. For example, a BCI-controlled robotic arm can provide patients diagnosed with neurodegenerative diseases such as Locked-in syndrome (LIS), Amyotrophic lateral sclerosis (ALS), and others with the ability to manipulate different objects. This study presents the optimization of the configuration parameters of a three-class Motor Imagery (MI) -based BCI for controlling a six Degrees of Freedom (DOF) robotic arm in a plane. Electroencephalography (EEG) signals are recorded from 64 positions on the scalp according to the International 10-10 System. In terms of the resulting classification of error rates, we investigated twelve time windows for the spatial filter and classifier calculation and three time windows for the variance smoothing time. The lowest error rates were achieved when using a 3 s time window for creating the spatial filters and classifier, for a variance time window of 1.5 s.

Pituitary apoplexy: An emergent and potential life-threatening complication of pituitary adenomas

BACKGROUND

Pituitary apoplexy is an emergent and potential life-threatening complication of pituitary adenomas if not managed properly. The aim of our study is to present our series of pituitary adenomas and to focus on the clinical, radiological, and surgical characteristics of this rare complication.

METHODS

In this study, a total of 143 patients with pituitary adenoma underwent surgical treatment between 2016 and 2018. All patients were operated using endoscopic endonasal transsphenoidal (EET) technique. The data of pituitary apoplexy cases were recorded. Resection rates, hormonal results, and visual outcomes of patients with pituitary apoplexy were evaluated.

RESULTS

Of the 143 patients, 8 (5.59%) were presented with the symptoms and radiological findings of pituitary apoplexy. The mean age was 26.75 years, and 4 (50%) of them were male and 4 were female. Pre-operative mean Knosp grading score was 2.1 All of eight patients underwent emergent surgical intervention and total resection was achieved in 75% of patients with apoplexy. Hormone levels were significantly decreased after surgery (p<0.05), except prolactin (p>0.05). Cerebrospinal fluid leakage occurred in one pa-tient. None of the patient with pituitary apoplexy died in our series.

CONCLUSION

Pituitary apoplexy is an important complication of pituitary adenomas. Early diagnosis and surgical intervention provide excellent ophthalmological and hormonal outcomes. Emergent EET approach is crucial for patients with ophthalmological findings and macroadenomas.