Not all aneurysms will rupture.
As medical imaging technology has improved and become more easily accessible, unruptured aneurysms are more frequently discovered. At first glance the discovery of an unruptured aneurysm may seem an opportunity to prevent a dreadful illness- and sometimes it is. However it can also raise very difficult questions- what is the risk my aneurysm will bleed in the future? Is that risk greater than the risks of having it treated now?
The natural history is what occurs if the aneurysm is left without treatment. The truth is that we cannot currently predict the future reliably and your specialist will only be able to offer an estimate of the risk of rupture over time. The best quality research we can presently refer to comes from The International Studies of Unruptured intracranial Aneurysms (ISUIA 1 and 2) and a large Japaneese clinical trial called the Unruptured Cerebral Aneurysm Study (UCAS). These data indicate that the relative size of the aneurysm and its location within the cranial cavity are the strongest indicators that it might bleed within a few years. There are many other factors that are thought to influence risk less reliably e.g. shape, age and other illnesses. There have been several attempts to develop clinical decision support tools
Some of these tools are based on purely on observational studies while others draw on expert opinion as well (consensus based models). Examples of such tools are the PHASES and UIATS models. In our experience there is sometimes poor agreement between models and so no one should be regarded as definitive. It is likely in the future such models will also take account of individual genetic susceptibilities. For now they can inform but do not replace a considered discussion between a patient and their neurovascular specialist.
The smallest aneurysms appeared to have relatively small risks of bleeding in the short term. The results of ISUIA are frequently, but erronously, cited as indicating small anterior circulation aneurysms below 7mm in diameter have no risk of bleeding in the short term. It is more correct to say their risk of bleeding may be less than the risks of treatment in the short term. We may also see that the risks of treatment increase as the aneurysms grow larger.
The decision to treat an unruptured aneurysm should always be a considered one and seldom needs to be rushed. Even if the aneurysm is considered of low risk of bleeding in the short term its discovery poses a real psychological burden for some. Therefore every case needs to be considered on its own merits. Our approach seeks to first educate the patient about the disease and about their options to manage the situation. Occasionally there is a strong case to recommend treatment but quite often a decision to treat may be more nuanced with strengths and drawbacks to the various options.
The identification of an unruptured aneurysm may impose a considerable psychological burden if electing not to treat the aneurysm. Living with the knowledge than one harbours a potentially treatable lesion which itself has the potential to kill or disable is very difficult for some even if that likelihood of that risk being realised is low.
For some that burden alone will be a reason to undergo treatment. If the diagnosis of an unruptured aneurysm is proving difficult another approach can be to seek psychological health coaching to assist one in decision making that is right for the individual. It is always useful to talk things through with your aneurysm specialist and there are no such things as "stupid" questions..
If opting to manage an anerurysm conservatively you may opt to have it re-imaged after a time. At present it is believed 6 to 9% of aneurysms which change shape or size if monitored for 10 years. Such changes, if confirmed, usually move us to recommend treatment where it is feasible as it is associated with a gradual increase in the risk of rupture.
If opting to manage an anerurysm conservatively you may opt to have it re-imaged after a time. At present it is believed 6 to 9% of aneurysms which change shape or size if monitored for 10 years. Such changes, if confirmed, usually move us to recommend treatment where it is feasible as it is associated with a gradual increase in the risk of rupture.
One should however bear in mind that repeated scanning is not in itself demonstrably protective against subarachnoid haemorrhage. If an aneurysm is destined to bleed it will usually do so without warning. There is no rule that it We are happy to discuss your needs on a case by case basis.