ABSTRACT
Background: The aim of the study was to evaluate the magnetic resonance imaging (MRI) findings in bilateral symmetrical Hirayama disease and find out MRI features which are probably more indicative of symmetrical Hirayama disease, thereby help in differentiating this entity from other motor neuron disease (MND). Methods: This prospective as well as retrospective study was carried out from December 2010 to September 2016 in a tertiary care center of northeast India on 92 patients with Hirayama disease. Only 19 patients having bilateral symmetric upper limb involvement at the time of presentation were included in this study sample. Results: Nineteen patients, who constituted 20.6% of 92 patients of clinical and flexion MRI confirmed Hirayama disease were found to have bilateral symmetrical wasting and weakness of distal upper limb muscles at the time of presentation. Mean ± standard deviation (SD) age of onset of the disease process was 21.7 ± 3.8 years with mean ± SD duration of illness of 3.6 ± 1.3 years. MRI revealed lower cervical cord flattening in 13 (68.4%) patients which was symmetrical in 6 (31.6%) patients and asymmetrical in 7 (36.8%) patients. In the majority of these patients, T2-weighted images (T2WI) cervical cord hyperintensities were found extending from C5 to C6 vertebral level. Seven (36.8%) patients in our study showed bilateral symmetric T2WI hyperintensities in anterior horn cells (AHC). Conclusion: Bilateral symmetrical involvement of Hirayama disease is an uncommon presentation. Symmetrical cervical cord flattening, T2WI cord and/or bilateral AHC hyperintensities were the major MRI findings detected. Flexion MRI demonstrated similar findings in both bimelic amyotrophy and classical unilateral amyotrophy. However, flexion MRI produced some distinguishing features more typical for bilateral symmetrical Hirayama disease which help to differentiate it from other MNDs.
ABSTRACT
INTRODUCTION: Isolated chest wall tuberculosis though a rare entity, the incidence of it has been on rise among immunocompromised population making it an important challenging diagnosis for the physicians. Its clinical presentation may resemble pyogenic chest wall abscess or chest wall soft tissue tumour. Sometimes it is difficult to detect clinically or on plain radiograph. AIM: The present study was conducted with an aim to evaluate the common sites and varying appearances of isolated chest wall tuberculosis. MATERIALS AND METHODS: A hospital based cross-sectional retrospective study was conducted in Assam Medical College and Hospital, a tertiary care centre in North East India. The study group comprise of 21 patients (n=15 male and n=6 females) with isolated chest wall tuberculosis without associated pulmonary or spinal involvement who were subjected to Computed Tomography/Magnetic Resonance Imaging (CT/MRI) of the thorax following initial Ultrasonogram (USG) evaluation of the local site. Pathological correlation was done from imaging guided sampling of the aspirate or surgery. RESULTS: Variable sites of involvement were seen in the chest wall in our patients (n=21), with chest wall abscess formation being the most common presentation and rib being the most common bony site affected in the thoracic cage. Bony sclerosis was noted in 11 patients (52.4%), periosteal reaction in 10 patients (47.6%) and sequestration in five patients (23.8%). CT/MRI not only localized the exact site and extent of the abscesses which facilitated guided aspirations, but also helped in detecting typical bony lesions thereby, differentiating from pyogenic osteomyelitis besides ruling out associated pulmonary or pleural involvement in such patients. CONCLUSION: Cross-sectional imaging plays an important role by giving a wholesome picture of both soft tissue and bony pathology. It is important to have adequate understanding of the radiologic manifestations of the chest wall involvement and complications of tuberculosis to facilitate diagnosis and in assessing response to treatment on follow up in patients.
