Differential diagnosis of white matter lesions: Nonvascular causes-Part II

Pearls & Oy-sters: AARS2 Leukodystrophy-Tremor and Tribulations

A 35-year-old woman with a progressive, bilateral upper limb tremor, personality change, behavioral disturbance, and primary ovarian insufficiency was found to have AARS2-related leukodystrophy. She had congenital nystagmus which evolved to head titubation by age 8 years and then developed an upper limb tremor in her mid-teens. These symptoms stabilized during her 20s, but soon after this presentation at age 35 years, neurologic and behavioral disturbances progressed rapidly over a 12-month period requiring transition to an assisted living facility with care support (4 visits/day) and assistance for all activities of daily living. MRI of the brain demonstrated confluent white matter changes predominantly involving the frontal lobes consistent with a leukodystrophy. All other investigations were unremarkable. Nongenetic causes of a leukodystrophy including sexually transmitted diseases and recreational drug use were excluded. Family history was negative for similar symptoms. Gene panel testing identified compound heterozygous pathogenic AARS2 mutations. This case highlights the importance of MRI brain imaging in progressive tremor syndromes, the utility of gene panels in simultaneous testing of multiple disorders with overlapping phenotypes, and the need for awareness of comorbid endocrinological disorders in many of the genetic leukodystrophies, whose identification may aid in clinical diagnosis.

Chronic flaccid quadriparesis from tract specific myelopathy in neurosyphilis

INTRODUCTION

Tract-specific myelopathies with distinctive imaging features are uncommon and typically occur with metabolic or paraneoplastic syndromes. We report a unique case of tract-specific myelopathy with neurosyphilis.

CASE PRESENTATION

A 53-year-old male presented with a four-month history of flaccid quadriparesis, sensory loss, and bladder dysfunction. His MRIs revealed striking symmetric T2-weighted hyperintensities in the lateral corticospinal tracts and dorsal columns of the cervical spinal cord that extended rostrally into the pyramidal decussation and medial lemnisci of the medulla oblongata. Nerve conduction and needle electromyography studies excluded axonal or demyelinating lower motor neuron disorders. The patient reported previous untreated primary syphilis and was seropositive on the T.pallidum hemagglutination assay. Penicillin therapy resulted in substantial clinical improvement.

DISCUSSION

Although syphilitic meningomyelitis is well-reported, our patient was unique because of the persistent flaccidity (possibly suggesting prolonged spinal shock) and striking tract-specific MRI patterns. These features are novel in syphilitic myelitis and suggest unknown mechanisms of tract-specific tropism and neuronal injury.

CONCLUSIONS

"Tract-specific" complete transverse myelopathy with persistent flaccid weakness and areflexia is a novel presentation of neurosyphilis. Early recognition and crystalline penicillin therapy can alleviate morbidity. Our report describes this patient's findings and discusses the differential diagnoses of tract-specific myelopathies.

Characterization of MRI White Matter Signal Abnormalities in the Pediatric Population

(1) Background and Purpose: The aim of this study was to retrospectively characterize WMSAs in an unselected patient cohort at a large pediatric neuroimaging facility, in order to learn more about the spectrum of the underlying disorders encountered in everyday clinical practice. (2) Materials and Methods: Radiology reports of 5166 consecutive patients with standard brain MRI (2006-2018) were searched for predefined keywords describing WMSAs. A neuroradiology specialist enrolled patients with WMSAs following a structured approach. Imaging characteristics, etiology (autoimmune disorders, non-genetic hypoxic and ischemic insults, traumatic white matter injuries, no final diagnosis due to insufficient clinical information, "non-specific" WMSAs, infectious white matter damage, leukodystrophies, toxic white matter injuries, inborn errors of metabolism, and white matter damage caused by tumor infiltration/cancer-like disease), and age/gender distribution were evaluated. (3) Results: Overall, WMSAs were found in 3.4% of pediatric patients scanned at our and referring hospitals within the ten-year study period. The majority were found in the supratentorial region only (87%) and were non-enhancing (78% of CE-MRI). WMSAs caused by autoimmune disorders formed the largest group (23%), followed by "non-specific" WMSAs (18%), as well as non-genetic hypoxic and ischemic insults (17%). The majority were therefore acquired as opposed to inherited. Etiology-based classification of WMSAs was affected by age but not by gender. In 17% of the study population, a definite diagnosis could not be established due to insufficient clinical information (mostly external radiology consults). (4) Conclusions: An "integrated diagnosis" that combines baseline demographics, including patient age as an important factor, clinical characteristics, and additional diagnostic workup with imaging patterns can be made in the majority of cases.

Effect of cerebral small vessel disease on cognitive impairment in Parkinson's disease

OBJECTIVES

To explore the association between cerebral small vessel disease (cSVD) and cognitive impairment (CI) in Parkinson's disease (PD).

METHODS

81 PD patients were recruited into the study from September 2018 to December 2020. The demographic characteristics and radiologic and laboratory data were collected. Cognitive assessments were carried out using the Montreal Cognitive Assessment. The association between cSVD and cognitive impairment was analyzed using univariate and binary logistic regression analysis.

RESULTS

The binary logistic regression analysis showed that, after correcting for age, educational years, hyperhomocysteinemia, hypertension, and diabetes mellitus, total cSVD scores (OR 1.55, 95% CI 1.07-2.27, P = 0.02), the presence of paraventricular white matter hyperintensity (PVH) (OR 11.78, 95% CI 3.08-45.01, P < 0.001), white matter hyperintensity (WMH) (OR 7.95, 95% CI 2.28-27.79, P = 0.001), and perivascular space (PVS) (OR 6.66, 95% CI 2.08-21.40, P = 0.001) were independent risk factors for PD-CI.

CONCLUSION

The presence of cSVD was associated with cognitive dysfunction in patients with PD. It may be beneficial to manage cSVD to prevent the progression of cognitive impairment in patients with PD.

Relationship of white matter hyperintensities with clinical features of seizures in patients with epilepsy

BACKGROUND

Although epilepsy is primarily known as a cortical disorder, there is growing body of research demonstrating white matter alterations in patients with epilepsy.

OBJECTIVE

To investigate the prevalence of white matter hyperintensities (WMH) and its association with seizure characteristics in patients with epilepsy.

METHODS

The prevalence of WMH in 94 patients with epilepsy and 41 healthy controls were compared. Within the patient sample, the relationship between the presence of WMH and type of epilepsy, frequency of seizures, duration of disease and the number of antiepileptic medications were investigated.

RESULTS

The mean age and sex were not different between patients and healthy controls (p>0.2). WMH was present in 27.7% of patients and in 14.6% of healthy controls. Diagnosis of epilepsy was independently associated with the presence of WMH (ß=3.09, 95%CI 1.06-9.0, p=0.039). Patients with focal epilepsy had higher prevalence of WMH (35.5%) than patients with generalized epilepsy (14.7%). The presence of WMH was associated with older age but not with seizure characteristics.

CONCLUSIONS

WMH is more common in patients with focal epilepsy than healthy controls. The presence of WMH is associated with older age, but not with seizure characteristics.

White Matter Lesions in Adults - a Differential Diagnostic Approach

OBJECTIVE

 Cerebral white matter lesions on MRI in adults are a common finding. On the one hand, they may correspond to a clinically incidental feature, be physiologically or age-associated, or on the other hand they may be the overture to a severe neurological disease. With regard to pathophysiological aspects, practical hints for the differential diagnostic interpretation of lesions in daily clinical practice are presented.

MATERIAL AND METHODS

 With special regard to the vascular architecture and supply of the cerebral white matter, physiological structures are schematically represented and pathophysiological processes are highlighted by comparative image analysis of equally angulated MR sequences.

RESULTS

 The most frequent vascular, inflammatory, metabolic, and neoplastic disease entities are presented on the basis of characteristic imaging findings and corresponding clinical- neurological constellations. The details of signal intensities and localization essential for differential diagnosis are highlighted.

CONCLUSION

 By means of comparative image analysis and the recognition of characteristic lesion patterns, taking into account anatomical principles and pathophysiological processes, the differential diagnostic classification of cerebral white matter lesions and associated diseases can be significantly facilitated. The additional consideration of clinical and laboratory findings is essential.

KEY POINTS

  · Cerebral white matter lesions can be a harmless secondary finding or overture to a severe neurological disease.. · The comparative image analysis of different sequences with identical angulation is crucial.. · With special regard to the vascular anatomy, different lesion patterns can be identified.. · The consideration of neurological and laboratory chemical constellations is essential for the differential diagnosis..

CITATION FORMAT

· Weidauer S, Wagner M, Hattingen E. White Matter Lesions in Adults - a Differential Diagnostic Approach. Fortschr Röntgenstr 2020; 192: 1154 - 1173.

Functional Connectivity Alterations in Neuromyelitis Optica Spectrum Disorder : Correlation with Disease Duration and Cognitive Impairment

PURPOSE

The aim of this study was to investigate resting state functional connectivity alterations within the main brain networks in neuromyelitis optica spectrum disorder (NMOSD) and their associations with disease duration, disability and cognitive dysfunction progression.

METHODS

Resting state functional magnetic resonance imaging (rs-fMRI), clinical and neuropsychological evaluations were obtained from 41 NMOSD patients and 41 healthy controls. Seed-voxel functional connectivity was analyzed in seven major hubs, including the default mode network, dorsal attention network, visual network, sensorimotor network, cerebellar network, thalamic network and reward-emotion network. Abnormalities of functional connectivity and correlations with disease duration, scores of the expanded disability status scale (EDSS), mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) were further explored.

RESULTS

Compared with healthy controls, NMOSD patients showed increased functional connectivity in the default mode network, dorsal attention network and thalamic network, while decreased in the visual network and cerebellum networks. At the regional level, increased functional connectivity involved the right superior temporal gyrus, left fusiform gyrus, left inferior parietal lobule, bilateral middle frontal gyrus and right precuneus, whereas functional connectivity was decreased in the right parahippocampal gyrus and left precuneus. Functional connectivity reduction in the right parahippocampal gyrus positively correlated with disease duration (r = 0.488, p = 0.001) and negatively correlated with MoCA scores (r = -0.330, p = 0.035).

CONCLUSION

The study demonstrated functional alterations in the rs-fMRI of NMOSD, which provide a novel insight into the large-scale selective functional reorganization and could be useful to reveal the characteristics of the physiological mechanism.

Magnetic Resonance Imaging and Clinical Features in Acute and Subacute Myelopathies

Differential diagnosis of acute and subacute transverse myelopathy includes inflammatory, infectious, vascular, metabolic and paraneoplastic etiologies. Information on the diagnostic approach to transverse myelopathy with regard to daily clinical practice is provided. The differentiation between five lesion patterns on magnetic resonance imaging (MRI) in myelitis may be helpful: (1) longitudinal extensive transverse myelitis, (2) short segment ovoid or peripherally located, (3) "polio-like", (4) granulomatous and (5) segmental with rash. A correlation with these imaging features is supported if the clinical course and neurological symptoms are known. Although the mean interval from onset to nadir of symptoms in spinal cord infarction is 1 h, an overlap with a fulminant course of myelitis is possible, and impaired diffusion may also occur in acute inflammatory processes. As a result, laboratory testing, including aquaporin-4 antibodies and cerebrospinal fluid analysis, is crucial for the correct interpretation of imaging findings. Moreover, the discrimination of acute complete and acute partial transverse myelitis is advantageous in order to identify diverse entities, the latter often being a precursor to multiple sclerosis. Additional brain imaging is mandatory in suspected demyelinating, infectious, neoplastic and systemic autoimmune disease. A symmetrical lesion pattern restricted to individual tracts or dorsal columns indicates subacute combined degeneration of the spinal cord and, in addition to deficiency syndromes, a paraneoplastic etiology should be considered.

Regional Cerebral Gray Matter Volume in HIV-Positive Patients with Executive Function Deficits

PURPOSE

To evaluate whether human immunodeficiency virus (HIV)-positive patients with and without executive functions deficits and healthy control subjects differ on cortical thickness and subcortical brain structures volume in vivo.

METHODS

In total, 34 HIV-positive patients with executive functions deficits were compared with 13 HIV-positive patients without executive functions deficits and 19 gender-, age-, and education-matched control subjects. Executive functions impairments were classified by performance on the Wisconsin card sorting test. T1 3-dimensional magnetization prepared rapid gradient echo-weighted imaging was performed using a 1.5 Tesla (magnetic resonance) MR scanner. FreeSurfer software was used to perform cortical reconstruction and volumetric segmentation of subcortical gray matter structures.

RESULTS

HIV-positive patients with executive functions deficits had smaller volumes in the right and left caudate compared with the HIV-positive patients without executive functions deficits and control groups. In addition, HIV-positive patients with executive functions deficits had smaller volumes in their left accumbens, right putamen, and globus pallidum compared with the control group. No significant differences in cortical thickness were observed between the groups.

CONCLUSION

HIV-positive patients with executive functions deficits have reduced volumes of several subcortical structures, primarily in the caudate nucleus.