Characterization and classification of kinesthetic motor imagery levels.

OBJECTIVE: Kinesthetic Motor Imagery (KMI) represents a robust brain paradigm intended for electroencephalography (EEG)-based commands in brain-computer interfaces (BCIs). However, ensuring high accuracy in multi-command execution remains challenging, with data from C3 and C4 electrodes reaching up to 92% accuracy. This paper aims to characterize and classify EEG-based KMI of multilevel muscle contraction without relying on primary motor cortex signals. Approach. A new method based on Hurst exponents is introduced to characterize EEG signals of multilevel KMI of muscle contraction from electrodes placed on the premotor, dorsolateral prefrontal, and inferior parietal cortices. EEG signals were recorded during a hand-grip task at four levels of muscle contraction (0, 10, 40, and 70% of the maximal isometric voluntary contraction). The task was executed under two conditions: first, physically, to train subjects in achieving muscle contraction at each level, followed by mental imagery under the KMI paradigm for each contraction level. EMG signals were recorded in both conditions to correlate muscle contraction execution, whether correct or null accurately. Independent component analysis (ICA) maps EEG signals from the sensor to the source space for preprocessing. For characterization, three algorithms based on Hurst exponents were used: the original (HO), using partitions (HRS), and applying semivariogram (HV). Finally, seven classifiers were used: Bayes network (BN), naive Bayes (NB), support vector machine (SVM), random forest (RF), random tree (RT), multilayer perceptron (MP), and k-nearest neighbours (kNN). Main results. A combination of the three Hurst characterization algorithms produced the highest average accuracy of 96.42% from kNN, followed by MP (92.85%), SVM (92.85%), NB (91.07%), RF (91.07%), BN (91.07%), and RT (80.35%). of 96.42% for kNN. Significance. Results show the feasibility of KMI multilevel muscle contraction detection and, thus, the viability of non-binary EEG-based BCI applications without using signals from the motor cortex.

Prevalence of basilar artery dolichoectasia in patients with acute ischemic stroke or transient ischemic attack in a single center of Spain. / Prevalencia de la dolicoectasia de la arteria basilar en pacientes con ictus isquémico agudo o ataque isquémico transitorio en un centro español.

INTRODUCTION: Basilar artery dolichoectasia (BADE) refers to abnormal enlargement or displacement of the basilar artery (BA). The previously reported prevalence of BADE among patients with stroke is 0.3 to 33.1%, however, it might vary among studied populations. We aim is to determine the prevalence of BADE in patients presenting with acute ischemic stroke (AIS) or transient ischemic attack (TIA) in a Stroke Unit in a single center in Spain. PATIENTS AND METHODS: Patients 50 years old or older presenting with AIS or TIA were eligible for inclusion. Demographic and clinical data were prospectively collected. Two neuroradiologists, blind to each other, assessed BA morphology. RESULTS: Among 126 patients, 34.1% fulfilled the criteria for BADE (ectasia or dolichosis). BADE was associated with advanced age (p = 0.04). Patients with fetal-type circle of Willis presented smaller BA diameters (2.9 ± 0.1 vs. 3.5 ± 0.1; p < 0.001), whereas patients with lacunar strokes presented a greater diameter than other stroke subtypes (3.8 ± 0.3 mm vs. 3.3 ± 0.1 mm; p = 0.04). DISCUSSION AND CONCLUSIONS: In this single-center study of patients presenting with AIS or TIA, the prevalence of BADE (ectasia or dolichosis) is high. Further studies focusing on Spaniards should confirm our results.

TITLE: Prevalencia de la dolicoectasia de la arteria basilar en pacientes con ictus isquémico agudo o ataque isquémico transitorio en un centro español.Introducción. La dolicoectasia de la arteria basilar (DEAB) es un término que se refiere a la dilatación o elongación anormal de la arteria basilar (AB). La prevalencia de DEAB notificada hasta la fecha en pacientes con ictus es del 0,3 al 33,1%; sin embargo, puede variar entre poblaciones. Se propuso determinar la prevalencia de DEAB en pacientes con ictus isquémico agudo (IIA) o ataque isquémico transitorio (AIT) en una unidad de ictus de España. Pacientes y métodos. Se consideró a pacientes de 50 años o más con IIA o AIT para ser incluidos. La información demográfica y clínica se obtuvo de forma prospectiva. Dos neurorradiólogos evaluaron la morfología de la AB de forma independiente. Resultados. De 126 pacientes, el 34,1% cumplió los criterios de DEAB (ectasia o dolicosis). La DEAB se asoció a mayor edad (p = 0,04). Los pacientes con la variante fetal del polígono de Willis presentaron menor diámetro de la AB (2,9 ± 0,1 frente a 3,5 ± 0,1; p < 0,001), mientras que pacientes con ictus lacunar presentaron diámetros mayores de la AB que otros subtipos de ictus (3,8 ± 0,3 mm frente a 3,3 ± 0,1 mm; p = 0,04). Discusión y conclusiones. En este estudio de centro único de pacientes con IIA o AIT, la prevalencia de DEAB (ectasia o dolicosis) fue alta. Estudios futuros enfocados en población española podrían confirmar nuestros resultados.

Rasch validation of the Keratoconus End-Points Assessment Questionnaire in a Spanish population with keratoconus.

OBJECTIVE: To carry out a methodologically complete validation of the Spanish version of the Keratoconus End-Points Assessment Questionnaire (KEPAQ) in a Spanish population with keratoconus. METHODS: Analytical, prospective study, including patients with keratoconus without previous surgical history, in which a measurement of quality of life was performed using the KEPAQ questionnaire, a complete exploration of the anterior pole and a corneal elevation topography with the Galilei G6 topographer. The evaluation of the psychometric characteristics of the scale in the studied population was carried out using Rasch modeling. RESULTS: A total of 140 patients with keratoconus were included, with a median age of 26.0 years, the majority (57.6%) being men. For the KEPAQ-E subscale, the median score was 69.3, with a reliability of 0.85 and an eigenvalue of the first contrast of 2.34. For the KEPAQ-F, the median score was 56.4, with a reliability of 0.88 and an eigenvalue of 2.00. All infit and outfit parameters were within normal limits for both subscales. A significant evaluation was found between the evaluations of both subscales (rho = 0.696; p < 0.001). The evaluations of the subscales and various clinical and tomographic characteristics showed a significant classification between them (p value between 0.048 y 0.001). CONCLUSION: The KEPAQ is a psychometrically robust and valid scale to evaluate quality of life in the Spanish population with keratoconus. This questionnaire can be easily used for both clinical and research aims.

Integrando la Inteligencia Artificial y los nuevos modelos de lenguaje en Oftalmología: Complicaciones del uso del aceite de silicona en cirugía vítreo-retiniana / Artificial Intelligence and new language models in Ophthalmology: Complications of the use of silicone oil in vitreoretinal surgery

La inteligencia artificial (IA) es una tecnología emergente que facilita tareas cotidianas y automatiza tareas en diversos campos como medicina. Sin embargo, la irrupción de un modelo de lenguaje en el mundo académico ha generado mucho interés. En esta comunicación se evalúa el potencial de Generative Pre-trained Transformer (ChatGPT), un modelo de lenguaje desarrollado por OpenAI; y de DALL-E 2, un generador de imágenes, en la escritura de artículos científicos en Oftalmología. El tema seleccionado es el de las complicaciones del uso de aceite de silicona (AS) en cirugía vítreo-retiniana. Se utilizó ChatGPT para generar un resumen y un artículo estructurado, sugerencias para un título y referencias bibliográficas. Se puede concluir que, a pesar del conocimiento demostrado, la precisión y fiabilidad científica en temas específicos es insuficiente para la generación automática de artículos con rigor científico. Por otro lado, todo científico debe conocer las posibles implicaciones éticas y legales de estas herramientas (AU)

Artificial intelligence (AI) is an emerging technology that facilitates everyday tasks and automates tasks in various fields such as medicine. However, the emergence of a language model in academia has generated a lot of interest. This paper evaluates the potential of ChatGPT, a language model developed by OpenAI, and DALL-E 2, an image generator, in the writing of scientific articles in ophthalmology. The selected topic is the complications of the use of silicone oil in vitreoretinal surgery. ChatGPT was used to generate an abstract and a structured article, suggestions for a title and bibliographical references. In conclusion, despite the knowledge demonstrated by this tool, the scientific accuracy and reliability on specific topics is insufficient for the automatic generation of scientifically rigorous articles. In addition, scientists should be aware of the possible ethical and legal implications of these tools (AU)

Artificial Intelligence and new language models in Ophthalmology: Complications of the use of silicone oil in vitreoretinal surgery.

Artificial intelligence (AI) is an emerging technology that facilitates everyday tasks and automates tasks in various fields such as medicine. However, the emergence of a language model in academia has generated a lot of interest. This paper evaluates the potential of ChatGPT, a language model developed by OpenAI, and DALL-E 2, an image generator, in the writing of scientific articles in ophthalmology. The selected topic is the complications of the use of silicone oil in vitreoretinal surgery. ChatGPT was used to generate an abstract and a structured article, suggestions for a title and bibliographical references. In conclusion, despite the knowledge demonstrated by this tool, the scientific accuracy and reliability on specific topics is insufficient for the automatic generation of scientifically rigorous articles. In addition, scientists should be aware of the possible ethical and legal implications of these tools.

Metastatic involvement of optic nerve in patient with breast and lung neoplasia.

Metastases are the most common adult intraocular tumors. However, those located in the optic nerve are very uncommon and are usually associated with spread to other locations such as the central nervous system, which darkens the prognosis. There is a case of a 67-year-old woman who reports progressive vision loss in the right eye of 15 days of evolution. The ophthalmological examination shows a relative afferent pupil defect in this eye and a pseudoedema of the papilla with retinal hemorrhages in the fundus. Personal history and characteristics of the optic nerve suggest the diagnosis of metastatic infiltration.

Afectación metastásica del nervio óptico en paciente con neoplasia de mama y pulmón / Metastatic involvement of optic nerve in patient with breast and lung neoplasia

Las metástasis son los tumores intraoculares más frecuentes del adulto. Sin embargo, aquellas localizadas en el nervio óptico son muy infrecuentes y suelen asociarse a diseminación en otras localizaciones como el sistema nervioso central, lo que ensombrece el pronóstico.Se presenta un caso de una mujer de 67 años que refiere pérdida de visión progresiva en el ojo derecho de 15 días de evolución. En la exploración oftalmológica se observa un defecto pupilar aferente relativo en dicho ojo y un pseudoedema de papila con hemorragias retinianas en el fondo de ojo. Los antecedentes personales y las características del nervio óptico apuntan al diagnóstico de infiltración metastásica. (AU)

Metastases are the most common adult intraocular tumors. However, those located in the optic nerve are very uncommon and are usually associated with spread to other locations such as the central nervous system, which darkens the prognosis.There is a case of a 67-year-old woman who reports progressive vision loss in the right eye of 15 days of evolution. The ophthalmological examination shows a relative afferent pupil defect in this eye and a pseudoedema of the papilla with retinal hemorrhages in the fundus. Personal history and characteristics of the optic nerve suggest the diagnosis of metastatic infiltration (AU)

Intraocular metastasis as a systemic presentation of neuroendocrine differentiation of prostate carcinoma.

A 68 year-old male was referred for assessment of an amelanotic lesion in the right eye (RE) that was associated with a gradual loss of visual acuity (VA), of 2 months onset, as the main symptom. It was noted in his medical history, that 6 years ago, he had prostate cancer treated with prostatectomy, lymphadenectomy, and coadjuvant local radiotherapy (RT). He was asymptomatic until 6 months ago, when a metastasis was discovered in the left femur, which was treated with radiotherapy. There were no findings of interest in the left eye (LE). His AV was very low in his RE, and in the eye fundus examination a mass without pigment was observed in the posterior pole with an adjacent exudative retinal detachment. Due to his personal history and results of the complementary tests such as ultrasound and magnetic resonance, the most likely diagnostic option was metastasis of prostate carcinoma, subsequently being confirmed with the histopathology results. Despite 4 cycles of chemotherapy, the patient did not show any clinical or radiological response, worsening until his death 3 months later.

Metástasis intraocular como presentación sistémica de un adenocarcinoma de próstata con diferenciación neuroendocrina / Intraocular metastasis as a systemic presentation of neuroendocrine differentiation of prostate carcinoma

Varón de 68 años derivado para valoración de una lesión amelanótica en el ojo derecho (OD) que asociaba como síntoma principal pérdida de agudeza visual (AV) progresiva de 2 meses de evolución. Entre sus antecedentes destaca un adenocarcinoma de próstata tratado con prostatectomía, linfadenectomía y radioterapia local (RT) coadyuvante hace 6 años. Asintomático hasta hace 6 meses, cuando se descubrió una metástasis en fémur izquierdo, tratada con radioterapia. La exploración del ojo izquierdo (OI) no tenía hallazgos de interés. En el OD su AV era muy baja y en el fondo de ojo (FO) se encontró una masa sin pigmento en polo posterior con un desprendimiento de retina (DdR) exudativo adyacente. Por sus antecedentes personales y características de las pruebas complementarias como ecografía o resonancia, la opción diagnóstica más probable era metástasis de adenocarcinoma de próstata, certificándose posteriormente con los resultados anatomopatológicos. A pesar de los 4 ciclos de quimioterapia (QT) recibidos, el paciente no obtuvo respuesta clínica ni radiológica, empeorando hasta su fallecimiento 3 meses después (AU)

A 68 year-old male was referred for assessment of an amelanotic lesion in the right eye (RE) that was associated with a gradual loss of visual acuity (VA), of 2 months onset, as the main symptom. It was noted in his medical history, that 6 years ago, he had prostate cancer treated with prostatectomy, lymphadenectomy, and coadjuvant local radiotherapy (RT). He was asymptomatic until 6 months ago, when a metastasis was discovered in the left femur, which was treated with radiotherapy. There were no findings of interest in the left eye (LE). His VA was very low in his RE, and in the eye fundus examination a mass without pigment was observed in the posterior pole with an adjacent exudative retinal detachment. Due to his personal history and results of the complementary tests such as ultrasound and magnetic resonance, the most likely diagnostic option was metastasis of prostate carcinoma, subsequently being confirmed with the histopathology results. Despite 4 cycles of chemotherapy, the patient did not show any clinical or radiological response, worsening until his death 3 months later (AU)