Since its first description optic nerve hypoplasia has been identified with increasing frequency, and a range of associated problems have been described. The major neurological and endocrine associations are well established, but those factors that predispose to the development of optic nerve hypoplasia remain unclear. To understand the aetiology of these problems better, and to formulate a management regime, we studied a consecutive series of 40 patients who were divided into three groups. Group 1 (n=24) had severe bilateral optic nerve hypoplasia; group 2 (n= 10) had mild, bilateral optic nerve hypoplasia; and group 3 (n=6) had unilateral optic nerve hypoplasia. Previously described aetiological factors (for example, low maternal age or maternal alcohol or drug ingestion) were not present in any of the groups; this removes the need to screen a specific population. It is important that careful neurological and developmental assessments are carried out in children with optic nerve hypoplasia to identify potential disease. The role of imaging is discussed.Patients and methods A diagnosis of optic nerve hypoplasia was made or confirmed by one of us (HEW) based on the appearance of a combination of features, the most important of which were (a) a small optic nerve head, (b) a second pigmented ring around the disc, and (c) tortuosity or abnormal origin of the vessels arising from the disc.'0 Rarely were all features present in any one eye. A detailed history was obtained from the mother in every case, specifically including the obstetric history, a history of smoking, alcohol consumption, or drug ingestion during pregnancy, and a history of problems in the neonatal period. The child's development and growth pattern were recorded and in all bilateral cases, and three unilateral, examination by a paediatric neurologist (SHG) was performed. In addition, most children had computed tomography performed, and, where it was considered appropriate, their endocrine state was investigated and any deficiency treated. Serial visual acuity measurements were taken using tests appropriate for age, and included preferred looking acuities in very young or retarded children.The diagnosis of optic nerve hypoplasia has been made with increasing frequency since its early descriptions,1 2 and it is no longer considered a rarity. A number of predisposing factors have been described, including maternal anticonvulsant ingestion,3 low maternal age,4 maternal alcohol or drug abuse,5 6 prenatal intracranial pathology,7 etc. In addition a wide range of neurological8 and endocrine9 associations have been recorded.In view of this array of associations it is difficult to identify a practical and appropriate management regime for each child with optic nerve hypoplasia. In particular, certain clinically important questions have not been directly addressed. Do only those children with severe optic nerve hypoplasia have neurological and endocrine problems? Do all children require some form of central nervous system imaging? Do positive resul...

Myopathic involvement of the perianal musculature is one of the less well recognised features of myotonic dystrophy in children and may present with physical signs suggestive of sexual abuse. Details of six children with myotonic dystrophy are presented to emphasise the importance of considering an underlying myopathic condition in the differential diagnosis of anal laxity. been seen here. For these reasons it is difficult to quantify the patient base from which these other five cases have been drawn.By emphasising the nature and range of these anal abnormalities, we hope to alert colleagues to this important muscular cause of anal sphincter dysfunction and so avoid confusion with anosexual abuse and the distress that related investigations will cause to families.