• progressive ventricular dilatation
• intraventricular haemorrhage
• intracranial pressure
• brain
• thyroid disorders
• Hashimoto’s thyroiditis

We read with interest the article of Murphy et al,¹ and it prompted us to review our own experience with progressive ventricular dilatation (PVD) over the past 22 years at the Maine Medical Center (MMC). Since 1980, we have used a single approach to management of PVD. As noted in previous publications, we have considered the need for intervention to be rapid head growth defined as an increase in occipitofrontal circumference of 2 cm a week or more rather than relying on imaging.^2,3 As this degree of head growth suggests increased intracranial pressure,⁴ we have intervened by directly draining ventricular fluid through a 21 gauge angiocath placed through the right coronal suture into the right lateral ventricle. This catheter is connected to a ventriculostomy drainage system, and drainage is continued for seven days if possible. The catheter is then removed and the decrease in head circumference and ventricular size recorded. The infant is watched for return of rapid head growth, and an angiocath is reinserted as needed. This procedure is repeated until the infant reaches about 2 kg in weight, and if rapid head growth continues, a permanent ventriculoperitoneal shunt is placed.³ We do not use pharmacological treatment or repeat lumbar puncture to treat PVD.

As pointed out by Murphy et al, PVD sufficient to require intervention occurs almost exclusively in infants with grade 3 or 4 intraventricular haemorrhage (IVH). As expected, the very low birthweight infants with high grade IVH have a high mortality. Table 1 shows a comparison between the outcomes for grade 3–4 IVH at MMC during the 1980s and over the past five years (1997–2001 inclusive), and the data of Murphy et al grouped in the same way. As noted, there is little difference over time or between studies. Overall mortality for grade 3–4 IVH was 33% (26/79) for Murphy et al, 33% (31/94) for MMC in the 1980s, and 31% (9/29) for MMC in 1997–2001. Until grade 3–4 IVH can be eliminated, posthaemorraghic hydrocephalus will continue to occur with high morbidity and mortality.