Predictive value of OCT and MRI for postoperative visual recovery in patients with chiasmal compressive lesions

Purpose We aimed to investigate the predictive value of retinal thickness measured by optical coherence tomography (OCT) and mass biometrics measured using magnetic resonance image (MRI) for visual recovery after surgery for removal of a mass compressing the optic chiasm. Methods Consecutive patients who showed typical temporal visual field defect (VFD) with respect to the vertical meridian due to a chiasmal compressive mass and who underwent mass removal surgery were recruited. Ophthalmic examination was performed preoperatively and postoperatively. Retinal thickness was measured by the Cirrus OCT. The height and size of the mass and suprasellar extension (SSE) in both the sagittal and coronal planes were evaluated. Patients were divided into two groups based on the improvement in VFD (mean deviation [MD] change ≥ 5 dB: group R; others: group NR) and clinical characteristics were compared. Results Fifteen patients were included in the study. Eight (53.3%) patients were allocated into group R and others (7 patients, 46.7%) into group NR. Age, sex, initial visual acuity, initial MD was not different between the two groups. The retinal thicknesses were not different while tumor height, volume, and both sagittal and coronal SSE were significantly different between the two groups. (p = 0.029, 0.014, <0.001, and <0.001, respectively) All MRI parameters showed significant predictive value for the degree of MD recovery. Conclusion MRI showed better predictive value than OCT in predicting postoperative VFD recovery in patients with temporal VFDs due to chiasmal compressive disorder.

Compressive Sensing Magnetic Resonance Image Reconstruction and Denoising using Convolutional Neural Network

Restoration of high-quality brain Magnetic Resonance Image (MRI) from the sparse under-sampled complex k-space signal is a widely studied ill-posed inverse transform problem. A deep learning-based data-adaptive and data-driven convolutional technique has been proposed for high-quality MRI recovery from its under-sampled complex domain k-space signal. The uniform subsampling process is very slow in phase-encoding to generate high-resolution images. The longer scan times degrade the perceptual image quality. Various factors contribute to image degradation during data acquisition such as the inception of body motion artifacts, the thermal energy effects of the body, and random noise artifacts due to voltage fluctuations. Keeping in view the patient’s critical condition and comfort, longer scan times are not preferred in practice. To reduce the image acquisition time, noise levels, and motion artifacts in the MR images, Compressive Sensing (CS) provides an accelerated way to reconstructs the high-quality MR image from very limited signal measurements acquired much below the Nyquist rate. However, such data acquisition strategies require advanced computer algorithms for the reconstruction of high-quality MRI from the undersampled MRI data. An improved CNN-based MRI reconstructed algorithm has been presented in this paper which shows better performance to reconstruct high-quality MRI than similar other MR image reconstruction algorithms. The performance of the proposed algorithm is measured by image quality checking tools such as normalized-MSE, PSNR, and SSIM.

Persistent Headache Caused by Post-Traumatic External Nasal Neuralgia: A Case Report

A 50-year-old female patient presented with a severe headache characterized by sharp pain localized in the right frontal area above the right eye. The patient’s right nostril was cauterized to stop a nosebleed one year prior to the start of the pain. Physical examinations revealed that the pain was aggravated by touch of the right lateral side of the nose and in severe attacks radiated to the maxillary frontal teeth. Blood tests, magnetic resonance image (MRI) and computer scanning (CT) scan images were all normal. The patient was diagnosed with post-traumatic external nasal neuralgia and symptoms were relieved and nearly resolved completely using a nasal cleanse and lubrication of the nose.

Recurrent Anti-AMPA Receptor Limbic Encephalitis: A Case Report and Literature Review

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor encephalitis is a relatively rare anti-neuronal surface antigen autoimmune encephalitis (LE). We described a case of a 47-year-old Chinese man having anti-AMPA receptor limbic encephalitis initially presented with cognitive decline, undetectable antibodies, and normal imaging findings in magnetic resonance image (MRI) and then developed into typical autoimmune limbic encephalitis a few months later with a course of multiple relapses. In addition, we found progressive brain atrophy in our case, which was a rare presentation of LE. This report also summarized the characteristics of nine reported cases of anti-AMPA receptor limbic encephalitis with relapse up to date. This case highlighted that autoimmune limbic encephalitis is an important differential diagnosis for patients with typical symptoms even when the MRI and antibodies are normal, and more attention should be paid to the relapse of anti-AMPA receptor encephalitis.