Open surgery for cerebral aneurysms has improved greatly since the surgical microscope was introduced the 1960s. Many surgical apparatus were developed, including aneurysm clips and surgical approaches for various sites of aneurysms, which contributed to safer neck clipping techniques and better clinical results. Endovascular treatment appeared and rapidly became popular soon after the release of the Guglielmi detachable coil in 1990. The International Subarachnoid Aneurysm Trial in the early 2000s has already demonstrated in a certain group of patients with ruptured aneurysms the superiority of endovascular coiling over the clipping. Endovascular treatments continued to advance, along with development of new techniques such as balloon-assisted coiling and of apparatus such as flow diverters, in the recent 10 years. The estimation of rupture rates of unruptured aneurysms also experienced a significant progress.
Moreover, there was also remarkable advancement in basic research regarding the mechanisms responsible for the initiation, development, growth, and rupture of cerebral aneurysms. As a result, inflammation is now known to play a central role in these mechanisms and is the major target for future medical treatment. There have also been recent reports on the genetic susceptibility loci for intracranial aneurysm.
However, various aneurysms that are difficult to treat, such as fusiform giant thrombosed aneurysms and arterial dissection, still remain. For unruptured aneurysms, a better estimation algorithm of a rupture rate of the individual aneurysm is preferred. The final goal to overcome cerebral aneurysms would be prevention of aneurysmal formation and rupture of cerebral aneurysms based on their mechanisms.
The ARUBA trial, which was a randomized trial, showed that in patients with unruptured brain arteriovenous malformations (bAVMs) followed for 33 months, medical treatment alone was superior to interventional therapy for the prevention of death or stroke. Since the publication of its results, this trial has experienced heavy criticisms in relation to its inappropriate design, low enrollment rate, low rate of surgical treatment, extremely short follow-up periods, and inappropriate conclusions. A number of researchers claimed that these issues are against the concept of prophylactic therapy, “to take an upfront risk to gain a long term benefit.” These critiques beg therefore for other trials to reestablish the management strategy for unruptured bAVMs. Three new projects (Prospective European Multimodality Registry, BARBADOS, and TOBAS) are currently being planned and partially launched.
Most skull base tumors are basically classified as pathologically benign tumors. However, their clinical courses are not usually benign due to anatomical proximity to critical neurovascular structures. It is thought that the extent of tumor removal is a significant factor for long tumor control, but at the same time, surgical radicality entails some risk that can lead to deterioration of the quality of life of the patient. Surgical outcomes depend largely on each institute and each neurosurgeon. Therefore, clinical evidence in the field of skull base tumor treatments is lacking. In this article, we briefly summarize recent clinical articles on skull base tumors and explain our strategy regarding treatment of skull base tumors.
The established best practice to treat medical diseases is “standard therapy”, which is widely accepted by healthcare professionals as it is the “common sense” approach to proper treatment. Pediatric brain tumors are not exempted in these standard therapies ; however, limitations apply. If allowance is made for the therapy to be reconstructed under multifaceted reexamination, these limitations pave the way to a “newer standard therapy,” reverification of foundation clinical trials, and overall experience in standard therapy.
We demonstrate in this series the use of cerebrospinal fluid placental alkaline phosphatase marker as a working example of intracranial germ cell tumor diagnosis, an optic nerve glioma multidisciplinary treatment therapy, as well as the new approach to brainstem tumor treatment/diagnosis when based on evidence-and experienced-based medicine. Although all these are yet to be common sense approached, they have the potential to be the next in line to become standard therapy.
We report here an extremely rare case of ruptured aneurysm arising from persistent primitive ventral ophthalmic artery (PPVOA). A 57-year-old woman presented with an unruptured right internal carotid-posterior communicating artery aneurysm and underwent clipping surgery. We found an anomalous origin ophthalmic artery arising from the anterior cerebral artery accompanying a very small aneurysm at the origin during the surgery. The very small aneurysm enlarged and ruptured suddenly on postoperative day 5, and was successfully treated with clipping plus wrapping. This temporary clip caused PPVOA wall thinning and fusiform dilatation, and was treated with wrapping.
This is the first report, to the best of our knowledge, that includes a ruptured aneurysm arising from the origin of PPVOA. Histological weakness in the vessel walls, such as decreased thickness or defects of the tunica media, may be found in congenital vascular anomalies or persistent primitive arteries. In the case described here, it has been considered that the same histological weakness has been contained. It was therefore concluded that microscopic operative stress led to an aneurysmal enlargement and rupture and PPVOA wall thinning and dilatation. We must be aware of vessel weakness in cases of congenital vascular anomalies or persistent primitive arteries.