Differentiating Neuromyelitis Optica-Related and Multiple Sclerosis-Related Acute Optic Neuritis Using Conventional Magnetic Resonance Imaging Combined With Readout-Segmented Echo-Planar Diffusion-Weighted Imaging

MRI signs helpful in the differentiation of patients with anterior ischaemic optic neuropathy and optic neuritis

BACKGROUND/AIMS

The aim of this study was to identify specific MRI characteristics of anterior ischaemic optic neuropathy (AION) and optic neuritis (ON) that would aid in the differentiation between these two diagnoses.

METHODS

We retrospectively analysed a consecutive case series including all patients with an MRI study of brain and orbit and the clinical diagnosis of either ON or AION. We examined the scans for restricted diffusion of the optic nerve, optic sheath diameter, enhancement and location of enhancement of the optic nerve and distribution of the white matter lesions.

RESULTS

Fifty patients met the inclusion criteria. We found an accuracy of 0.98 for the discrimination between AION and ON based solely on parameters extracted from MRI data. Dominance analysis to determine the most influential parameters showed that the enhancement pattern of the optic nerve and distribution of the white matter lesions had the biggest impact on the classification and led to a discrimination accuracy of 0.9 when used alone.

CONCLUSION

In patients with an inconclusive clinical diagnosis, optic nerve enhancement pattern and distribution of white matter lesions can aid in the diagnosis and differentiation between AION and ON. Diffusion-weighted imaging did not add significant information to the diagnosis or help to differentiate between the two conditions.

RESOLVE-DWI-based deep learning nomogram for prediction of normal-sized lymph node metastasis in cervical cancer: a preliminary study

BACKGROUND

It is difficult to predict normal-sized lymph node metastasis (LNM) in cervical cancer clinically. We aimed to investigate the feasibility of using deep learning (DL) nomogram based on readout segmentation of long variable echo-trains diffusion weighted imaging (RESOLVE-DWI) and related patient information to preoperatively predict normal-sized LNM in patients with cervical cancer.

METHODS

A dataset of MR images [RESOLVE-DWI and apparent diffusion coefficient (ADC)] and patient information (age, tumor size, International Federation of Gynecology and Obstetrics stage, ADC value and squamous cell carcinoma antigen level) of 169 patients with cervical cancer between November 2013 and January 2022 were retrospectively collected. The LNM status was determined by final histopathology. The collected studies were randomly divided into a development cohort (n = 126) and a test cohort (n = 43). A single-channel convolutional neural network (CNN) and a multi-channel CNN based on ResNeSt architectures were proposed for predicting normal-sized LNM from single or multi modalities of MR images, respectively. A DL nomogram was constructed by incorporating the clinical information and the multi-channel CNN. These models' performance was analyzed by the receiver operating characteristic analysis in the test cohort.

RESULTS

Compared to the single-channel CNN model using RESOLVE-DWI and ADC respectively, the multi-channel CNN model that integrating both two MR modalities showed improved performance in development cohort [AUC 0.848; 95% confidence interval (CI) 0.774-0.906] and test cohort (AUC 0.767; 95% CI 0.613-0.882). The DL nomogram showed the best performance in development cohort (AUC 0.890; 95% CI 0.821-0.938) and test cohort (AUC 0.844; 95% CI 0.701-0.936).

CONCLUSION

The DL nomogram incorporating RESOLVE-DWI and clinical information has the potential to preoperatively predict normal-sized LNM of cervical cancer.

Magnetic Resonance Image in Monitor and Diagnosis of Patients with Neuromyelitis Optica

This study was aimed to investigate the craniocerebral magnetic resonance imaging (MRI) measurement and clinical characteristics of patients with neuromyelitis optica (NMO) and multiple sclerosis (MS). 50 patients with NMO (NMO group) and 50 patients with MS (MS group) were studied. The clinical manifestations, brain injury morphology, MRI signal characteristics, brain distribution characteristics, and related laboratory tests (serum aquaporin 4 [AQP4] antibody) were statistically analyzed. The results showed that the analysis of clinical manifestations of patients revealed that optic neuritis (37 cases) was the most common disease in NMO patients, and myelitis (16 cases) was more common in MS patients than NMO patients. There were significant differences in gender ratio, abnormal expression of brain MR1, positive serum AQP4-IgG, and other immune diseases and symptoms between the two groups (P < 0.05). When the lesions measured by MRI were located in the white matter area of the cerebral hemisphere, the image showed blurred edges and a relatively symmetrical distribution. When the lesions measured by MRI were located around the medulla oblongata, the lesions mainly involved the central gray matter and white matter of the spinal cord, with patchy and line-like long T1 and long T2 signals. Moreover, in the late stage of recurrence of spinal cord disease, severe spinal cord atrophy may occur. In conclusion, craniocerebral MRI measurement in NMO patients can provide more basis for the diagnosis and differential diagnosis of the disease, so as to improve the diagnostic level of NMO.

Differences in the involved sites among different types of demyelinating optic neuritis in traditional MRI examination: A systematic review and meta-analysis

Background

Magnetic resonance imaging (MRI) plays a significant role in assessing optic neuropathy and providing more detailed information about the lesion of the visual pathway to help differentiate optic neuritis from other visual disorders. This study aims to systematically review the literature and verify if there is a real difference in lesion location among different demyelinating optic neuritis (DON) subtypes.

Methods

A systematic search was conducted including 8 electronic databases and related resources from the establishment of the database to August 25th, 2020. We classified DON into 5 subtypes and divided the visual pathways into five segments mainly comparing the differences in the involved visual pathway sites of different subtypes.

Results

Fifty-five studies were included in the analysis, and the abnormal rate was as high as 92% during the acute phase (within 4 weeks of symptom onset). With respect to lesion location, the orbital segment of the optic nerve was the most frequently involved (87%), whereas optic tract involvement was very rare. Involvement of the orbital segment was more common in myelin oligodendrocyte glycoprotein antibody-related optic neuritis (MOG-ON) (78%) and chronic relapsing inflammatory optic neuropathy (CRION) (81%), while the lesion was found to be located more posteriorly in neuromyelitis optica spectrum disorder-related optic neuritis (NMOSD-ON). With respect to lesion length, approximately 77% of MOG-ON patients had lesions involving more than half of the optic nerve length.

Conclusions

MRI examination is recommended for DON patients in the acute phase. In MOG-ON, anterior involvement is more common and the involved length is mostly more than 1/2 of the optic nerve length, whereas posterior involvement, intracranial segment, optic chiasm, or optic tract, is more common in NMOSD-ON.

Prospero registration number

CRD42020222430 (25-11-2020).

MRI Patterns Distinguish AQP4 Antibody Positive Neuromyelitis Optica Spectrum Disorder From Multiple Sclerosis

Neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) are inflammatory diseases of the CNS. Overlap in the clinical and MRI features of NMOSD and MS means that distinguishing these conditions can be difficult. With the aim of evaluating the diagnostic utility of MRI features in distinguishing NMOSD from MS, we have conducted a cross-sectional analysis of imaging data and developed predictive models to distinguish the two conditions. NMOSD and MS MRI lesions were identified and defined through a literature search. Aquaporin-4 (AQP4) antibody positive NMOSD cases and age- and sex-matched MS cases were collected. MRI of orbits, brain and spine were reported by at least two blinded reviewers. MRI brain or spine was available for 166/168 (99%) of cases. Longitudinally extensive (OR = 203), "bright spotty" (OR = 93.8), whole (axial; OR = 57.8) or gadolinium (Gd) enhancing (OR = 28.6) spinal cord lesions, bilateral (OR = 31.3) or Gd-enhancing (OR = 15.4) optic nerve lesions, and nucleus tractus solitarius (OR = 19.2), periaqueductal (OR = 16.8) or hypothalamic (OR = 7.2) brain lesions were associated with NMOSD. Ovoid (OR = 0.029), Dawson's fingers (OR = 0.031), pyramidal corpus callosum (OR = 0.058), periventricular (OR = 0.136), temporal lobe (OR = 0.137) and T1 black holes (OR = 0.154) brain lesions were associated with MS. A score-based algorithm and a decision tree determined by machine learning accurately predicted more than 85% of both diagnoses using first available imaging alone. We have confirmed NMOSD and MS specific MRI features and combined these in predictive models that can accurately identify more than 85% of cases as either AQP4 seropositive NMOSD or MS.

At this Junction…

An 81-year-old woman developed painful vision loss to hand motions in the right eye over a several-day period. Dilated fundus examination revealed no acute pathology, but automated perimetry showed a superotemporal visual field defect in the asymptomatic left eye, suggestive of a junctional scotoma. Magnetic resonance imaging demonstrated enhancement of the right optic nerve extending to its junction with the optic chiasm. The patient's vision failed to improve with intravenous corticosteroids, but demonstrated significant improvement with therapeutic plasma exchange. She was subsequently found to be seropositive for aquaporin-4 autoantibodies, confirming the diagnosis of neuromyelitis optic spectrum disorder.

Clinical characteristics of optic neuritis phenotypes in a 3-year follow-up Chinese cohort

To evaluate the clinical characteristics of optic neuritis (ON) with different phenotypes. This prospective study recruited patients with new-onset ON between January 2015 and March 2017 who were followed-up for 3 years. They were divided into the myelin oligodendrocyte glycoprotein-seropositive (MOG-ON), aquaporin-4-seropositive (AQP4-ON), and double-seronegative (seronegative-ON) groups, and their clinical characteristics and imaging findings were evaluated and compared. Two-hundred-eighty patients (405 eyes) were included (MOG-ON: n = 57, 20.4%; AQP4-ON: n = 98, 35.0%; seronegative-ON: n = 125, 44.6%). The proportion of eyes with best-corrected visual acuity > 20/25 at the 3-year follow-up was similar between the MOG-ON and seronegative-ON groups; the proportion in both groups was higher than that in the AQP4-ON group (p < 0.001). Relapse rates were higher in the MOG-ON and AQP4-ON groups than in the seronegative-ON group (p < 0.001). Average retinal nerve fiber layer (RNFL) thickness at 3 years was similar between the MOG-ON and AQP4-ON groups (63.41 ± 13.39 and 59.40 ± 11.46 μm, p = 0.476) but both were thinner than the seronegative-ON group (74.06 ± 11.14 μm, p < 0.001). Macular ganglion cell-inner plexiform layer (GCIPL) revealed the same pattern. Despite RNFL and GCIPL thinning, the MOG-ON group’s outcome was as favorable as that of the seronegative-ON group, whereas the AQP4-ON group showed unsatisfactory results.

MRI characteristics of MOG-Ab associated disease in adults: An update

Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.

High resolution diffusion-weighted imaging with readout segmentation of long variable echo-trains for determining myometrial invasion in endometrial carcinoma

Background

We assessed the image quality of endometrial cancer lesions by readout segmentation of long variable echo-trains (RESOLVE) diffusion-weighted imaging (DWI) compared with that by single-shot echo-planar imaging (SS-EPI) DWI, aimed to explore the value of RESOLVE DWI for determining myometrial invasion and clinical stage in endometrial cancer.

Materials and methods

From April 2017 to March 2018, a total of 30 endometrial cancer patients (mean age 52.8 ± 9.0 years), who had undergone RESOLVE DWI and SS-EPI DWI, were included in the study. The image quality of endometrial carcinoma by two kinds of DWI scanning methods was compared qualitatively and quantitatively. The Spearman rank correlation test was used to assess the correlation of qualitative image quality scores between two readers. The accuracy of two DWI methods in detecting myometrial invasion and staging of endometrial carcinoma was calculated according to postoperative pathological results. The indexes were analyzed including sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).

Results

The qualitative score of RESOLVE DWI group was superior to SS-EPI DWI group in every aspect of five aspects (all P < 0.001). Interobserver agreement of depiction was good or excellent in two DWI sequences. Signal to noise ratio and contrast to noise ratio values in RESOLVE DWI group were both higher than those in SS-EPI DWI group (P<0.001). No statistical difference of apparent diffusion coefficient value was observed between two DWI groups (P = 0.261). The specificity, accuracy, PPV, and NPV of estimating myometrial invasion by RESOLVE DWI in three cases (intramucosal lesion, <50% superficial invasion and ≥ 50% deep invasion) were all higher than those by SS-EPI DWI for endometrial carcinoma. Especially RESOLVE DWI was valuable in judging <50% superficial invasion (95%CI:0.586, 0.970). No significant difference in accuracy staging was between the two DWI groups (P = 0.125).

Conclusion

RESOLVE DWI can provide higher quality images of endometrial carcinoma than SS-EPI DWI. The high-quality images are helpful for precise assessment of myometrial invasion in endometrial cancer.

Autologous nonmyeloablative hematopoietic stem cell transplantation for neuromyelitis optica

OBJECTIVE

To determine if autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT) could be a salvage therapy for neuromyelitis optica spectrum disorder (NMOSD).

METHODS

Thirteen patients were enrolled in a prospective open-label cohort study (11 NMOSD aquaporin-4-immunoglobulin G [AQP4-IgG]-positive, 1 NMOSD without AQP4, and 1 NMOSD AQP4-IgG-positive with neuropsychiatric systemic lupus erythematosus [SLE]). Following stem cell mobilization with cyclophosphamide (2 g/m²) and filgrastim, patients were treated with cyclophosphamide (200 mg/kg) divided as 50 mg/kg IV on day -5 to day -2, rATG (thymoglobulin) given IV at 0.5 mg/kg on day -5, 1 mg/kg on day -4, and 1.5 mg/kg on days -3, -2, and -1 (total dose 6 mg/kg), and rituximab 500 mg IV on days -6 and +1. Unselected peripheral blood stem cells were infused on day 0. AQP4-IgG antibody status was determined by Clinical Laboratory Improvement Amendments-validated ELISA or flow cytometry assays. Cell-killing activity was measured using a flow cytometry-based complement assay.

RESULTS

Median follow-up was 57 months. The patient with coexistent SLE died of complications of active lupus 10 months after HSCT. For the 12 patients with NMOSD without other active coexisting autoimmune diseases, 11 patients are more than 5 years post-transplant, and 80% are relapse-free off all immunosuppression (p < 0.001). At 1 and 5 years after HSCT, Expanded Disability Status Scale score improved from a baseline mean of 4.4 to 3.3 (p < 0.01) at 5 years. The Neurologic Rating Scale score improved after HSCT from a baseline mean of 69.5 to 85.7 at 5 years (p < 0.01). The Short Form-36 health survey for quality of life total score improved from mean 34.2 to 62.1 (p = 0.001) at 5 years. In the 11 patients whose baseline AQP4-IgG serostatus was positive, 9 patients became seronegative by the immunofluorescence or cell-binding assays available at the time; complement activating and cell-killing ability of patient serum was switched off in 6 of 7 patients with before and after HSCT testing. Two patients remained AQP4-IgG-seropositive (with persistent complement activating and cell-killing ability) and relapsed within 2 years of HSCT. No patient with seronegative conversion relapsed.

CONCLUSION

Prolonged drug-free remission with AQP4-IgG seroconversion to negative following nonmyeloablative autologous HSCT warrants further investigation.

The quest for high spatial resolution diffusion-weighted imaging of the human brain in vivo

Diffusion-weighted imaging, a contrast unique to MRI, is used for assessment of tissue microstructure in vivo. However, this exquisite sensitivity to finer scales far above imaging resolution comes at the cost of vulnerability to errors caused by sources of motion other than diffusion motion. Addressing the issue of motion has traditionally limited diffusion-weighted imaging to a few acquisition techniques and, as a consequence, to poorer spatial resolution than other MRI applications. Advances in MRI imaging methodology have allowed diffusion-weighted MRI to push to ever higher spatial resolution. In this review we focus on the pulse sequences and associated techniques under development that have pushed the limits of image quality and spatial resolution in diffusion-weighted MRI.