Anna Pichiecchio

Muscle MRI in inherited neuromuscular disorders: past, present, and future.

Interest in muscle MRI has been largely stimulated in the last few years by the recognition of an increasing number of genetic defects in the field of inherited neuromuscular disorders. Muscle ultrasound (US) and computed tomography (CT) have been used to detect the presence of muscle involvement in patients affected by these disorders, but until recently the use of muscle MRI has been, with a few exceptions, limited to detecting inflammatory forms. The aim of this review is to illustrate how muscle MRI, in combination with clinical evaluation, can contribute to the selection of appropriate genetic tests and more generally in the differential diagnosis of genetically distinct forms of neuromuscular disorders. Possible future applications of muscle MRI are also discussed. J. Magn. Reson. Imaging 2007.

Congenital muscular dystrophies with defective glycosylation of dystroglycan A population study

Background: Congenital muscular dystrophies (CMD) with reduced glycosylation of alpha-dystroglycan (α-DG) are a heterogeneous group of conditions associated with mutations in six genes encoding proven or putative glycosyltransferases. Objectives: The aim of the study was to establish the prevalence of mutations in the six genes in the Italian population and the spectrum of clinical and brain MRI findings. Methods: As part of a multicentric study involving all the tertiary neuromuscular centers in Italy, FKRP, POMT1, POMT2, POMGnT1, fukutin, and LARGE were screened in 81 patients with CMD and α-DG reduction on muscle biopsy (n = 76) or with a phenotype suggestive of α-dystroglycanopathy but in whom a muscle biopsy was not available for α-DG immunostaining (n = 5). Results: Homozygous and compound heterozygous mutations were detected in a total of 43/81 patients (53%), and included seven novel variants. Mutations in POMT1 were the most prevalent in our cohort (21%), followed by POMT2 (11%), POMGnT1 (10%), and FKRP (9%). One patient carried two heterozygous mutations in fukutin and one case harbored a new homozygous variant in LARGE. No clear-cut genotype-phenotype correlation could be observed with each gene, resulting in a wide spectrum of clinical phenotypes. The more severe phenotypes, however, appeared to be consistently associated with mutations predicted to result in a severe disruption of the respective genes. Conclusions: Our data broaden the clinical spectrum associated with mutations in glycosyltransferases and provide data on their prevalence in the Italian population.

Muscle Magnetic Resonance Imaging Involvement in Muscular Dystrophies with Rigidity of the Spine

The aim of the study was to evaluate whether the visual analysis of muscle magnetic resonance imaging scans can identify specific patterns of muscle involvement.

Effectiveness of intravenous immunoglobulin treatment in adult patients with steroid-resistant monophasic or recurrent acute disseminated encephalomyelitis

Abstract Randomized Controlled Trials have not jet established the best pharmacological management of Acute Disseminated Encephalomyelitis (ADEM). High dose steroids are usually employed with good results, but in a few cases the clinical outcome is poor. In other patients, particularly those affected by the site restricted ADEM variants (myelitis), the disease shows a recurrent course resembling that of Multiple Sclerosis. We present here five patients, 3 of them affected by classic disseminated encephalomyelitis and 2 by a post infectious myelitis, which showed a good response to intravenous immunoglobulin (IVIg) after steroid treatment failure. In our report high dose steroids administration was substantially uneffective in all but one case, who showed a good response only during the first episode. On the contrary IVIg injection (0,4 gr/kg/day) produced a marked functional improvement in all patients starting within the first five days of drug administration and reaching a maximum within three weeks. One patient experienced a good effect nothwithstanding a steady dysability. In all cases, clinical evidence was supported by MRI controls showing improving posttreatment changes.

Muscle MRI in adult-onset acid maltase deficiency

We report the spectrum of muscle involvement on magnetic resonance imaging in 11 patients with a molecularly confirmed diagnosis of adult-onset acid maltase deficiency at different clinical stages. Muscle magnetic resonance imaging showed a selective progressive pattern of muscle involvement with a constant involvement of the adductor magnus and semimembranosus at the early stage of the disease and a later fatty infiltration of the long head of the biceps femoris, semitendinosus and of the anterior thigh muscles. In the advanced phases a selective sparing of sartorius, rectus, and gracilis muscles and peripheral portions of the vastus lateralis was also evident. Muscle strength and magnetic resonance imaging findings were positively correlated. The results suggest that muscle magnetic resonance imaging may provide valuable diagnostic guidance for the assessment of accurate selective muscular involvement in acid maltase deficiency and may help monitor the progression of the disorder. Further control studies in a larger cohort are needed to evaluate the specificity of these findings.

Pisa Syndrome in Parkinson's Disease: Clinical, Electromyographic, and Radiological Characterization

Abnormal postures of the trunk are a typical feature of Parkinsons disease (PD). These include Pisa syndrome (PS), a tonic lateral flexion of the trunk associated with slight rotation along the sagittal plane. In this study we describe clinical, electromyographic (EMG), and radiological features of PS in a group of 20 PD patients. All patients with trunk deviation underwent EMG and radiological (RX and CT scan) investigation. Clinical characteristics of patients with PS were compared with a control group of PD patients without trunk deviation. PD patients with PS showed a significantly higher score of disease asymmetry compared with the control group. In the majority of patients with PS, trunk bending was contralateral to the side of symptom onset. EMG showed abnormal tonic hyperactivity on the side of the deviation in the paravertebral thoracic muscles and in the abdominal oblique muscles. CT of the lumbar paraspinal muscles showed muscular atrophy more marked on the side of the deviation, with a craniocaudal gradient. PS may represent a complication of advanced PD in a subgroup of patients who show more marked asymmetry of disease and who have detectable hyperactivity of the dorsal paravertebral muscles on the less affected side. This postural abnormality deserves attention and proper early treatment to prevent comorbidities and pain.

Parry–Romberg syndrome with migraine and intracranial aneurysm

Parry-Romberg syndrome or progressive facial hemiatrophy (PFH) is a rare disease of unknown etiology characterized by atrophy of the skin and subcutaneous tissue on one side of the face. The authors present the case of a 32-year-old woman with PFH who had migraine and an intracranial aneurysm. The findings support the hypothesis that the disease could be related to a neural crest migration disorder, from which both fronto-nasal mass and cranial vessels take origin.

Advanced magnetic resonance imaging of neuromyelitis optica: a multiparametric approach

Background: Several authors have used advanced magnetic resonance imaging (MRI) techniques to investigate whether patients with neuromyelitis optica (NMO) have occult damage in normal-appearing brain tissue, similarly to multiple sclerosis (MS). To date, the literature contains no data derived from the combined use of several advanced MRI techniques in the same NMO subjects. Objective: We set out to determine whether occult damage could be detected in the normal-appearing brain tissue of a small group of patients with NMO using a multiparametric MRI approach. Methods: Eight female patients affected by NMO (age range 44–58 years) and seven sex- and age-matched healthy controls were included. The techniques used on a 1.5 T MRI imaging scanner were magnetization transfer imaging, diffusion tensor imaging, tract-based spatial statistics, spectroscopy and voxel-based morphometry in order to analyse normal-appearing white matter and normal-appearing grey matter. Results: Structural and metabolic parameters showed no abnormalities in normal-appearing white matter of patients with NMO. Conversely, tract-based spatial statistics demonstrated a selective alteration of the optic pathways and the lateral geniculate nuclei. Diffusion tensor imaging values in the normal-appearing grey matter were found to be significantly different in the patients with NMO versus the healthy controls. Moreover, voxel-based morphometry analysis demonstrated a significant density and volume reduction of the sensorimotor cortex and the visual cortex. Conclusions: Our data disclosed occult structural damage in the brain of patients with NMO, predominantly involving regions connected with motor and visual systems. This damage seems to be the direct consequence of transsynaptic degeneration triggered by lesions of the optic nerve and spine.

Severe steroid-resistant post-infectious encephalomyelitis: General features and effects of IVIg

Based on their presumed immuno-mediated etiology, post-infectious CNS disorders are commonly treated with high-dose steroids. Factors influencing treatment effectiveness, possible alternative options for steroid-resistant cases, and their outcome profiles, remain unclear. We here describe the clinical features, the prognosis and the efficacy of i. v. immunoglobulins (IVIg) in a series of severe ADEM refractory to steroids. We performed an inception cohort study on inpatients of the Neurologic and Infectious Disease Clinics, consecutively admitted over eight years, with a minimum two-year follow-up. Nineteen patients affected by classic and site-restricted ADEM were treated with IVIg after steroid failure. Five other patients received IVIg as first-line treatment due to steroids contraindications: although not included in the analysis, they were monitored for anecdotal comparison. Steroids were administered as IV 6-methylprednisolone (6-MP) 500/1000 mg daily until a maximum dose of 6–8 g; IVIg were administered at 0.4 g/kg/day for 5 days. The outcome was assessed by the Scripps Neurological Rating Scale (SNRS) score with determined periodicity. We observed that steroid-resistant patients showed high prevalence of PNS damage (89%) and myelitis (95 %). Other features were old age, severe disability at onset, and moderate to severe blood-brain-barrier (BBB) damage on CSF. In 10/19 patients (53 %) IVIg were effective, the clinical improvement beginning within the end of the five-day cycle,without relapses. Prominent effects of IVIg were detectable on motor dysfunction. Milder onset disability (p = 0.013) and lower CSF albumin (p = 0.006) were the predictors of IVIg response.Among steroid-free patients, 3/5 were responsive to IVIg. We conclude that IVIg can be useful in a portion of patients with severe steroid-resistant ADEM and prominent motor dysfunction. Unsolved issues regard the usefulness of IVIg in less selected groups, and the spectrum of their clinical effects.

Limbic hyperconnectivity in the vegetative state

Objective: To investigate functional connectivity between the default mode network (DMN) and other networks in disorders of consciousness. Methods: We analyzed MRI data from 11 patients in a vegetative state and 7 patients in a minimally conscious state along with age- and sex-matched healthy control subjects. MRI data analysis included nonlinear spatial normalization to compensate for disease-related anatomical distortions. We studied brain connectivity data from resting-state MRI temporal series, combining noninferential (independent component analysis) and inferential (seed-based general linear model) methods. Results: In DMN hypoconnectivity conditions, a patients DMN functional connectivity shifts and paradoxically increases in limbic structures, including the orbitofrontal cortex, insula, hypothalamus, and the ventral tegmental area. Conclusions: Concurrently with DMN hypoconnectivity, we report limbic hyperconnectivity in patients in vegetative and minimally conscious states. This hyperconnectivity may reflect the persistent engagement of residual neural activity in self-reinforcing neural loops, which, in turn, could disrupt normal patterns of connectivity.