Endovascular occlusion of basilar bifurcation aneurysms with electrolytically detachable coils

Mechanoactive materials in cardiac science

Mechanically active biomaterials such as shape memory materials, liquid crystal elastomers, dielectric elastomer actuators, and conductive polymers could be used in mechanical devices to augment heart function or condition cardiac cells and artificial tissues for regenerative medicine solutions.

Biomedical applications of thermally activated shape memory polymers

Shape memory polymers (SMPs) are smart materials that can remember a primary shape and can return to this primary shape from a deformed secondary shape when given an appropriate stimulus. This property allows them to be delivered in a compact form via minimally invasive surgeries in humans, and deployed to achieve complex final shapes. Here we review the various biomedical applications of SMPs and the challenges they face with respect to actuation and biocompatibility. While shape memory behavior has been demonstrated with heat, light and chemical environment, here we focus our discussion on thermally stimulated SMPs.

Prototype laser-activated shape memory polymer foam device for embolic treatment of aneurysms

Conventional embolization of cerebral aneurysms using detachable coils is time-consuming and often requires retreatment. These drawbacks have prompted the development of new methods of aneurysm occlusion. We present the fabrication and laser deployment of a shape memory (SMP) polymer expanding foam device. Data acquired in an in vitro basilar aneurysm model with and without flow showed successful treatment, with the flow rate affecting foam expansion and the temperature at the aneurysm wall.

Clinical experience of 153 patients with posterior circulation aneurysms

OBJECTIVE

To study the morbidity and mortality of patients with aneurysms of the posterior circulation (basilar-vertebral system) and investigate the natural history of these aneurysms without surgical intervention.

METHODS

Of 1232 patients with intracranial aneurysms admitted to Tiantan Hospital from January 1990 to October 2001, 153 (12.4%) had aneurysms of the posterior circulation. Their clinical and angiographic data were reviewed retrospectively. Additionally, to June 2002, 38 of the cases managed without surgery have been followed by telephone and correspondence. For these patients, the annual aneurysm rupture rate was estimated in "person-years".

RESULTS

Patients were aged 4-69 years (mean 40.8). The peak incidence was in the 5th decade. There were 88 males and 65 females. One hundred and two patients (66.7%) were treated surgically, and of these, 60 (58.8%) had an excellent outcome, 10 (9.8%) a good outcome, 29 (28.4%) a fair outcome and 3 (2.9%) died. The other 51 (33.3%) patients were treated conservatively for various reasons. Of these, 13 died of ruptured aneurysm in hospital. Ten of these patients had had a previous subarachnoid haemorrhage and 3 had not. The other 38 surviving, conservatively managed patients were followed for 5-95 months (mean 23). Of them, 3 (17.6%) died of aneurysmal rupture, giving an annual rupture rate of 9.2%, or 3/32.47 patient years.

CONCLUSIONS

To prevent death and disability due to aneurysmal rupture, posterior circulation aneurysms should be treated aggressively.

Neurological, neuropsychological, and psychosocial outcome following treatment of unruptured intracranial aneurysms: a review and commentary

Thirty studies published between 1977 and 2001 that focus on outcome following unruptured intracranial aneurysm (UIA) treatment are reviewed. Although findings from these studies suggest outcome from UIA treatment is reasonably good (between 5% and 25% morbidity and between 0-7% mortality), many of the complex issues associated with the treatment of UIAs remain controversial. Most of the studies reviewed address outcome in terms of mortality and neurological morbidity. Very few studies exist which include measures of outcome such as cognitive status, psychosocial functioning and quality of life. Given that patients facing treatment tend to be healthy middle-aged adults with many years of active working and social life ahead of them, it is important to take into account the long-term consequences of either harboring an UIA, or having it treated. The small number of studies that include cognitive, psychosocial and quality of life outcomes are reviewed in some detail and suggestions made for improving future UIA outcome research.