VANCOUVER - Medical opinion is divided over whether twin girls born joined at the head in Vancouver last year can be separated.

The eight-month-old girls, Krista and Tatiana Hogan, live with their parents in Vernon, B.C., but returned to Vancouver on Tuesday for a CT scan at Children's Hospital.

Their grandmother, Louise McKay, says about half the doctors consulted think separation is possible while the other half disagree and the CT scan was ordered to help make a final decision on the issue.

The girls' brain stems are fused and earlier tests show one twin is circulating more blood through both the twins' brains.

McKay says seven doctors from around the world are consulting on the case and she expects a decision in early August on whether the girls can be separated.

The twins were born in October to Felicia Simms and father Brendan Hogan, who have two other children.