Atypical Case of MOG Antibody-Associated Optic Neuritis with Roth Spots.

PURPOSE: To report an atypical case of MOG antibody-associated optic neuritis with Roth spots and widespread retinal hemorrhages. CASE REPORT: A 49-year-old woman complained of 1 week history painful visual loss in the left eye. Funduscopy exam showed a severe optic disc edema associated with multiple peripapillar hemorrhages, peripheral retinal hemorrhages and Roth spots in the left eye. Orbit MRI revealed an hyperintensity in the left optic nerve, enhanced with gadolinium. The serum Myelin Oligodendrocyte (MOG) antibodies was found positive. Early intravenous high dose of steroids rapidly improved visual acuity and fundus abnormalities rapidly resolved. CONCLUSION: Retinal hemorrhages can also be detected in case of optic disc edema associated with an optic neuritis, as seen in MOGAD.

The brainstem in multiple sclerosis: MR identification of tracts and nuclei damage.

OBJECTIVE: To evaluate the 3D Fast Gray Acquisition T1 Inversion Recovery (FGATIR) sequence for MRI identification of brainstem tracts and nuclei damage in multiple sclerosis (MS) patients. METHODS: From april to december 2020, 10 healthy volunteers and 50 patients with remitted-relapsing MS (58% female, mean age 36) underwent MR imaging in the Neuro-imaging department of the C.H.N.O. des Quinze-Vingts, Paris, France. MRI was achieved on a 3 T system (MAGNETOM Skyra) using a 64-channel coil. 3D FGATIR sequence was first performed on healthy volunteers to classify macroscopically identifiable brainstem structures. Then, FGATIR was assessed in MS patients to locate brainstem lesions detected with Proton Density/T2w (PD/T2w) sequence. RESULTS: In healthy volunteers, FGATIR allowed a precise visualization of tracts and nuclei according to their myelin density. Including FGATIR in MR follow-up of MS patients helped to identify structures frequently involved in the inflammatory process. Most damaged tracts were the superior cerebellar peduncle and the transverse fibers of the pons. Most frequently affected nuclei were the vestibular nuclei, the trigeminal tract, the facial nerve and the solitary tract. CONCLUSION: Combination of FGATIR and PD/T2w sequences opened prospects to define MS elective injury in brainstem tracts and nuclei, with particular lesion features suggesting variations of the inflammatory process within brainstem structures. In a further study, hypersignal quantification and microstructure information should be evaluated using relaxometry and diffusion tractography. Technical improvements would bring novel parameters to train an artificial neural network for accurate automated labeling of MS lesions within the brainstem.

Early and severe dyspnea after supracricoid partial laryngectomy.

We present the case of a not-yet-reported complication that occurred during the immediate postoperative period after supracricoid partial laryngectomy. We include a review of the literature on complications following this procedure, emphasizing technical considerations that are critical during this surgery. Clinical, diagnostic, and operative findings are presented, as is a differential diagnosis for early and severe postoperative dyspnea following supracricoid laryngectomy.

Descending mediastinitis with mediastinal abscess after supracricoid partial laryngectomy.

We document a rare and not-yet-reported condition after supracricoid partial laryngectomy: the development of descending mediastinitis with mediastinal abscess. We present a case in which early diagnosis and team management allowed for a successful outcome. The pathophysiology of this severe complication, as well as its diagnosis, management, and prevention, is discussed, together with a review of the medical scientific literature.

Signal-to-noise ratio improvement in dynamic contrast-enhanced CT and MR imaging with automated principal component analysis filtering.

PURPOSE: To develop a new automated filtering technique and to evaluate its ability to compensate for the known low contrast-to-noise ratio (CNR) in dynamic contrast material-enhanced (DCE) magnetic resonance (MR) and computed tomographic (CT) data, without substantial loss of information. MATERIALS AND METHODS: Clinical data acquisition for this study was approved by the institutional review board. Principal component analysis (PCA) was combined with the fraction of residual information (FRI) criterion to optimize the balance between noise reduction efficiency and information conservation. The PCA FRI filter was evaluated in 15 DCE MR imaging data sets and 15 DCE CT data sets by two radiologists who performed visual analysis and quantitative assessment of noise reduction after filtering. RESULTS: Visual evaluation revealed a substantial noise reduction while conserving information in 90% of MR imaging cases and 87% of CT cases for image analysis and in 93% of MR imaging cases and 90% of CT cases for signal analysis. Efficient denoising enabled improvement in structure characterization in 60% of MR imaging cases and 77% of CT cases. After filtering, CNR was improved by 2.06 ± 0.89 for MR imaging (P < .01) and by 5.72 ± 4.82 for CT (P < .01). CONCLUSION: This PCA FRI filter demonstrates noise reduction efficiency and information conservation for both DCE MR data and DCE CT data. FRI analysis enabled automated optimization of the parameters for the PCA filter and provided an optional visual control of residual information losses. The robust and fast PCA FRI filter may improve qualitative or quantitative analysis of DCE imaging in a clinical context. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100231/-/DC1.

Radiofrequency ablation of needle tract seeding in hepatocellular carcinoma.

A tumor needle tract seeding, 20 mm in diameter, was detected with magnetic resonance (MR) imaging in a 72-year-old man, 10 months after radiofrequency ablation of a 55-mm subcapsular hepatocellular carcinoma. This seeding was successfully treated with ultrasound-guided percutaneous radiofrequency ablation. No recurrence was found after a 2-year follow-up either on contrast-enhanced computed tomography or MR imaging. Needle tract seeding treatment is not well established. Percutaneous radiofrequency ablation of such seeding is one elegant potential treatment option. Efficacy seems promising but has to be confirmed in larger series. Further evaluation is needed.