Brain aneurysms are more likely to rupture if they are growing even if they are small, a new study in Radiology reports. Aneurysms of 7 mm or more are the size where the benefits of treatment generally outweigh the risks of rupture, based on earlier studies. This had been interpreted that size alone is determinative of rupture risk. But ones that grow in size over time are at even greater risk for rupture, regardless of size. This means that all aneurysms of any size need to be followed. If they are growing, then treatment needs to be considered. Monitoring can be done by annual CT examination which is readily available and not cost prohibitive.
Subarachnoid hemorrhage (SAH) cannot be ruled out by CT scan or history with physical examination alone, according to a recent study published in Annals of Emergency Medicine. A lumbar puncture with examination of the cerebrospinal fluid is the only way to rule subarachnoid bleeding. Previous studies have reported that a clinical decision rule can rule out SAH with 100% sensitivity. Other studies have reported that a CT scan of the brain within 6 hours can rule SAH out with 100% accuracy. This study says otherwise. The researchers retrospectively looked at cases of SAH in patients with normal neurological exams and also looked at the accuracy of the clinical rule test and the CT imaging test. Sixty two percent (62%) of these patients had cerebral aneurysms and were presenting with signs of small early sentinel bleeds. This important proper diagnosis allows treatment time prior to catastrophic rupture.