M. de Silva

Specific learning disability in children with neurofibromatosis type 1: Significance of MRI abnormalities

To determine whether previously reported areas of increased T2 signal intensity on MRI examination in children with neurofibromatosis type 1 (NF 1) are associated with deficits in development and learning common in this population, we evaluated 51 children with NF 1 (aged 8 to 16 years). Forty children completed the full assessment protocol (MRI, medical, psychometric, speech therapy, and occupational therapy assessments). The mean Full Scale IQ scores for the entire study population showed a left shift compared with the normal population, and the distribution of IQ scores was bimodal, suggesting that there are two populations of patients with NF 1–those with and those without a variable degree of cognitive impairment. There was no association between lower IQ scores and any clinical variable. Areas of increased T2 signal intensity unidentified bright objects (UBO+) were present in 62.5% of the study population, and their presence was not related to clinical severity, sex, age, socioeconomic status, macrocephaly, or family history of NF 1. However, compared with children without areas of increased T2 signal intensity (UBO-), the UBO+ group had significantly lower mean values for IQ and language scores and significantly impaired visuomotor integration and coordination. Children with areas of increased T2 signal intensity were at a much higher risk for impaired academic achievement. Children without increased T2 signal on MRI (UBO-) did not significantly differ from the general population in any measure of ability or performance. Areas of increased T2 signal on MRI represent dysplastic glial proliferation and aberrant myelination in the developing brain and are associated with deficits in higher cognitive function. The presence of these abnormal signals on MRI divides the NF 1 population into two distinct groups anatomically and developmentally (UBO+ and UBO-). These two groups should be considered separately in the assessment and management of learning disability in children with NF 1.

MRI findings in children with neurofibromatosis type 1: a prospective study.

To determine the frequency and nature of MRI lesions in children with neurofibromatosis type I (NF1), 50 patients aged 8 to 16 years were evaluated prospectively with cranial MRI. Forty-one children were asymptomatic with respect to central nervous system pathology, and 50 % were macrocephalic. Sixteen patients (32 %) had normal MRI examinations. Thirty-two patients (64 %) had high intensity lesions on T2-weighted images and 16 patients (32 %) had hyperintense lesions on T1-weighted images. Seven patients (14 %) had ventricular dilatation (associated with increased intracranial pressure in 2) and 11 patients (22 %) had optic pathway lesions (optic glioma in 7). MRI was superior to CT in differentiating optic sheath thickening and optic nerve tortuosity from optic glioma in four patients. An intracranial tumour (ependymoma) and sphenoid wing dysplasia were evident in individual patients. Findings previously unreported in NF1 included an aqueductal web resulting in hydrocephalus, intraocular neurofibroma resulting in retinal detachment, and asymptomatic enlargement of the septum pellucidum. T1 and T2 signal abnormalities in isolation were not associated with neurological deficits or the occurrence of macrocephaly, and all lesions that required intervention were suspected clinically. Macrocephaly in the absence of increased intracranial pressure or accelerated head growth is not an indication for neuroimaging in children with NF1. However, the majority of children (68 %) had disease-specific abnormalities and thus MRI may provide a useful adjunct to clinical evaluation in the diagnosis of equivocal cases.

Liposomes in arthritis: a new approach.

Intra-articular liposomal cortisol palmitate in a dose equivalent to 2 mg of cortisol produced a worthwhile therapeutic response in patients with rheumatoid arthritis. This may represent a valuable new approach to treatment.

The radiology of neonatal necrotizing enterocolitis (NEC). A review of 47 cases and the literature.

The radiological findings in 47 neonates with necrotizing enterocolitis (NEC) are reviewed. The presence of nonspecific, generalized bowel dilatation is stressed as being an important sign in early diagnosis and the progress of the distribution of the dilated loops is important in evaluating progress of the disease process. It is thus the key to the radiology of NEC. Intramural gas and portal venous gas are not always related to the severity of the disease and their disappearance is not always related to clinical improvement. These signs are therefore poor prognostic indicators. Important radiological indications for surgery besides free intraperitoneal gas and free fluid include: 1. diminished bowel gas with asymmetric loops, and 2. persistent dilated loops. Because of the number of colonic strictures seen at our hospital we advise routine barium enemas (several weeks after the acute phase) in all infants who have had NEC. Following bowel resection contrast studies of both distal and proximal remaining bowel are essential to exclude further stricture formation prior to final reanastomosis.

Severe cervical dysplasia and nasal cartilage calcification following prenatal warfarin exposure

We present an infant who was exposed to warfarin throughout pregnancy and has warfarin embryopathy. When the child was examined radiologically at 20 months areas of calcification were visible in the septal and alar cartilages of the small external part of the nose. The location of this ectopic calcification is consistent with that seen in an animal model of the warfarin embryopathy. It supports the hypothesis that warfarin interferes with the prenatal growth of the cartilaginous nasal septum by inhibiting the normal formation of a vitamin K-dependent protein that prevents calcification of cartilage. The child also had severe abnormalities of the cervical vertebrae and secondary damage to the spinal cord. Cervical vertebral anomalies are a relatively common finding in the warfarin embryopathy and in the related Binder syndrome.

Infantile myofibromatosis: a radiological review

Infantile myofibromatosis is an unusual condition generally presenting in the newborn period. It may be solitary or multicentric. Sites involved include skin and subcutaneous tissues, muscle, bones and viscera. Nine cases are presented, including one case in an identical twin whose co-twin remained asymptomatic. The radiological features and differential diagnosis are discussed.

Hemiplegia due to posterior cerebral artery occlusion.

Background Hemiplegia is a rare manifestation of posterior cerebral artery occlusion. The acute clinical picture may be difficult to differentiate from occlusion of the middle cerebral artery. A mechanism for the hemiplegia has not been conclusively determined. Case Description We describe a patient with hemiplegia secondary to posterior cerebral artery occlusion by an embolized fragment of a prosthetic valve. Computed tomographic scan showed the foreign body just distal to the origin of the posterior cerebral artery with infarction of its vascular territory. These findings were later confirmed at autopsy. There was no radiological or autopsy evidence of involvement of the other cerebral arteries or their territories. Conclusions The patient provides further evidence that occlusion of the posterior cerebral artery just distal to its junction with the posterior communicating artery may produce contralateral hemiplegia without oculomotor nerve nucleus involvement. (Stroke. 1993;24:1757-1760.)

Sacral chondromyxoid fibroma

A 15-year-old girl with a limp and weakness and wasting of the left leg, was found to have a large chondromyxoid fibroma of the sacrum. The lesion presented difficulties in diagnosis because of its unusual site, neurological presentation, large size and extensive extension into the soft tissues of the pelvis and buttock.

Chest radiograph abnormalities in very low birthweight survivors of chronic neonatal lung disease

Objective: To determine whether the neonatal chest radiograph (CXR) at 28 days in very low birthweight (VLBW) infants who develop chronic neonatal lung disease (CNLD) predicts oxygen therapy duration or CXR abnormalities in early childhood. Also, to assess the inter‐observer reliability of the radiologists scoring the CXR.

Infantile hepatic haemangioma: Investigation and treatment

Infantile hepatic haemangiomas are benign tumours which tend to regress in late infancy. We describe five infants with hepatic haemangioma, three of whom developed congestive cardiac failure. Technetium‐99m labelled red blood cell scan was useful in the diagnosis and follow‐up of the lesion. The three symptomatic infants were treated with prednisone (2 mg/kg per day) for 2 months in addition to digoxin and diuretics. Significant clinical improvement occurred within 3 weeks in each case. We conclude that the red blood cell scan is a good non‐invasive diagnostic test and recommend corticosteroids as initial management for symptomatic infantile hepatic haemangiomas.