Muscle histology vs MRI in Duchenne muscular dystrophy

OBJECTIVE

There are currently no effective treatments to halt the muscle breakdown in Duchenne muscular dystrophy (DMD), although genetic-based clinical trials are being piloted. Most of these trials have as an endpoint the restoration of dystrophin in muscle fibers, hence requiring sufficiently well-preserved muscle of recruited patients. The choice of the muscles to be studied and the role of noninvasive methods to assess muscle preservation therefore require further evaluation.

METHODS

We studied the degree of muscle involvement in the lower leg muscles of 34 patients with DMD >8 years, using muscle MRI. In a subgroup of 15 patients we correlated the muscle MRI findings with the histology of open extensor digitorum brevis (EDB) muscle biopsies. Muscle MRI involvement was assigned using a scale 0-4 (normal-severe).

RESULTS

In all patients we documented a gradient of involvement of the lower leg muscles: the posterior compartment (gastrocnemius > soleus) was most severely affected; the anterior compartment (tibialis anterior/posterior, popliteus, extensor digitorum longus) least affected. Muscle MRI showed EDB involvement that correlated with the patient's age (p = 0.055). We show a correlation between the MRI and EDB histopathologic changes, with MRI 3-4 grades associated with a more severe fibro-adipose tissue replacement. The EDB was sufficiently preserved for bulk and signal intensity in 18/22 wheelchair users aged 10-16.6 years.

CONCLUSION

This study provides a detailed correlation between muscle histology and MRI changes in DMD and demonstrates the value of this imaging technique as a reliable tool for the selection of muscles in patients recruited into clinical trials.

Congenital peri-sylvian syndrome presenting with intractable seizures

We report a case of Congenital peri-sylvian syndrome with intractable seizures, hypotonia and feeding problems since birth. MRI brain helped in making an early diagnosis and counselling parents.

Moyamoya disease: a review

Moyamoya is probably an inherited vasocclusive disease first described in Japan and now reported from all over the world. Genetic linkage studies and study of the factors possibly involved in its pathogenesis have shed new light on this disease. There is some suggestion that the pathogenesis may vary between races. A number of revascularization procedures have been devised. There is still controversy regarding the timing and the type of surgery. Functional MRI and PET scanning may provide more objective criterion on the outcome of these procedures. Neuropsychological studies may also be of use in judging the benefits of surgery. In this review, some of the recent advances in the study of the genetics and pathogenesis of the disease are reviewed and the clinical manifestation and the role of surgery are discussed. Relative lack of literature from outside Japan and the Korean peninsula has hampered the understanding of the disease in other countries.

Ataxias of childhood

BACKGROUND

This review examines the causes of ataxias in children. It is a relatively common manifestation of neurological diseases in children. The etiology of ataxia covers a broad range, from infections to rare hereditary metabolic diseases. A systematic approach is required to make the correct diagnosis.

REVIEW SUMMARY

The more common causes of ataxias in children are discussed in detail. The importance of recognizing potentially reversible conditions such as vitamin E deficiency and Refsum's disease is stressed. Recent advances in molecular genetics of some of the chronic ataxias are discussed. The importance of categorizing diseases based on the duration of symptoms and associated signs is discussed. Treatment options are mentioned.

CONCLUSION

Ataxia is a common mode of presentation of cerebellar, posterior column, and vestibular disease in children. Awareness of the spectrum of disease entities that cause ataxia in childhood may lead to better diagnosis.

Coronary artery bypass grafting for coronary thrombosis complicating polycythaemia rubra vera. Case report

Coronary thrombosis complicating polycythaemia rubra vera in a 42-year-old woman was treated with coronary artery bypass grafting. Nonatherosclerotic causes of coronary obstruction, though rare, should be considered, especially in younger patients.

Malignant melanoma of the right atrium: antemortem diagnosis by transvenous biopsy

About half of all patients with malignant melanoma have cardiac metastases. Histological confirmation antemortem of a secondary malignant melanoma of the heart is difficult. The diagnosis of a secondary melanoma in the right atrium was confirmed by transvenous biopsy in a 46 year old woman who had had a melanoma excised from her right leg two years before.