**9. Aneurysm clipping in elderly**

At present, there are no corroborated management guidelines for UIAs in elderly patients, yet the retrospective reports reveal excellent results for both treatment strategies [130–132]. It has been shown that elderly patients with UIAs are less likely to die following aneurysmal rupture SAH than younger and/or female patients [37, 40, 78, 133, 134]. Therefore, a conservative approach may also be considered especially for small UIAs. Even so, the advanced age in itself supposedly increases the risk of periprocedural complications. Surgical interventions are correlated with larger amounts of blood loss, higher treatment-related costs, and longer hospitalizations than endovascular techniques, though provide a complete and maintainable aneurysmal occlusion

#### **Figure 4.**

*Illustrative case 2. (A) CTA 3D reconstruction of a 55-year-old male with multiple cerebral aneurysms two on the right middle cerebral artery and one the left middle cerebral artery bifurcation. He presented to emergency department with right-sided weakness with gradual onset 3 days prior to surgery. Video 2 is available at: https://bit.ly/2Z8W6rm. He underwent microsurgical clipping via a right frontolateral craniotomy. All the clips were placed in the same procedure. (B) Postoperative CTA 3D reconstruction showing proper clip placement. He was discharged without any additional deficit.*

[130, 135, 136]. Despite the differences in regard to mortality being relatively small, they are nonetheless significant and favor endovascular coiling as the safest of the two [136]. Aside from preventing rupture, interventional therapy has demonstrated cognitive improvement without causing further intellectual deficits, in addition to a decrease in anxiety levels [137, 138]. Older patients harboring MIAs without a history of SAH can be managed conservatively, whereas those at risk or with a previous SAH should be treated in a one- or two-staged intervention [119]. Moreover, coiling might prove more appropriate for those with serious comorbidities and in an altered clinical state, while clipping is more suitable in the presence of intracranial vasospasm or hematomas [69]. The same as for younger patients with MIAs, the ruptured lesion should always be managed first and foremost, yet for unruptured MIAs treatment may only be indicated if the risk related to observation outweighs those of therapy.

#### **10. Neurological and clinical outcome after clipping**

There are conflicting reports regarding the postprocedural outcomes for these interventions. Short-term outcomes generally favor endovascular procedures, with a higher incidence of postinterventional adverse events after surgery [74, 139]. According to Kim et al., there is no significant difference regarding all-cause mortality at 7 years after the elective treatment of UIAs via either clipping or coiling [140]. The meta-analysis performed by Ruan et al. showed similar outcomes for the two procedures [141]. On the other hand, in their meta-analysis, Falk Delgado et al. reported a higher independent outcome and lower mortality after coiling of UIAs [108]. The outcomes may be improved with the intraoperative use of electrophysiological monitoring, fluorescence angiography, or Doppler ultrasonography [142]. Surgical clipping of UIAs does not negatively impact quality of life nor does it affect cognitive functions in such a way that patients are unable to work or drive at 6 weeks or 1 year after the intervention [143, 144]. The risk of poor outcome for patients below the age of 65 stands at around 2–4% and rises with aneurysm size, which when compared to the 0.3–0.9% risk of annual rupture might outclass the natural history in a few years after treatment [89, 103, 145]. Nonetheless, mortality is extremely low, if not inexistent in these series. Therefore, a more aggressive treatment may be acceptable for UIAs in younger patients. Although some series

**163**

sometimes unavoidable.

*Preventing Rupture: Clipping of Unruptured Intracranial Aneurysms*

independence, as will be shown in a later subchapter.

intervention into immediate and delayed complications.

can regain control of the situation and ensure proper clip placement.

**11. Complications of surgical clipping**

have demonstrated clipping of UIAs is effective and has no mortality even in elderly [131], the risk of a poorer outcome increases in this age group, with higher instances of disability and death than endovascular procedures specifically in the presence of comorbidities [132, 136]. Retreatment of intracranial aneurysms is also associated with a higher mortality rate [146]. However, in our experience, clipping of solitary UIAs yields excellent results, with no mortality and a high degree of functional

Since clipping is a surgical intervention, there are chances of developing complications related to the procedure, medical and infectious complications as well as those attributable to anesthesia. The following paragraphs will focus on the complications of clipping itself. These can be divided according to timing of onset after the

IAR is one of the most frequent and most dreaded periprocedural complications [147]. This is especially the case for inexperienced (and oftentimes reckless) surgeons; however, preoperative GCS has also been shown to play a role in predicting this event [148]. It occurs especially around the time of neck dissection and clip placement or adjustment and is capable of hampering the microsurgical procedure, sometimes being life-threatening [149]. Nevertheless, it is significantly less frequent for UIAs than for the ruptured lesions [147]. A steady technique, proper discovery of the parent artery, temporary clipping proximal to the aneurysm, and aspiration

Ischemic complications may also arise from improper clip placement or due to thromboembolism from the aneurysm. The type and severity of neurological consequences depend mostly on the location of the aneurysm [150–153]. The most frequent type of postoperative events and possibly even underestimated, ischemia leads to poorer outcomes at discharge and often entails a reintervention [153, 154]. After clipping of UIAs, transcranial Doppler studies show a decrease in transient reduction in cerebrovascular reactivity on the side of the aneurysm, leading to a proneness toward cerebral ischemia [155]. Endovascular procedures apparently bear a higher risk for thromboembolic events and ischemia [156], yet a recent meta-analysis showed that there was no statistical difference between coiling and clipping in respect to this event [141]. Incidence of perforator territory ischemia is higher for aneurysms of the A1 segment, whereas olfactory disturbances are more common for lesions of the ACoA [157]. Silent ischemic lesions are fairly frequent (up to 10% of procedures) and mostly irreversible, though rarely disabling [153, 157]. It has been argued that induced hypertension may reduce the effects of delayed cerebral ischemia [158]. Regardless, there is still no conclusive data to sustain the benefits of induced hypertension, whereas serious adverse events are

Another undesirable complication is the occlusion of the surrounding arteries, especially deep and subtle perforators. Again, dissection, proper magnification and illumination of the surgical field, and adequate brain relaxation can improve the visibility of the aneurysmal neck and surrounding structures. It is also important to utilize clips adjusted to aneurysm size and morphology. Electrophysiological monitoring, micro-Doppler ultrasonography, or intraoperative angiography can rapidly detect an arterial occlusion and facilitate repositioning of the clip [152, 159].

Clip slippage can happen when advanced atherosclerosis thickens the aneurysmal wall, making it impossible for the clip to close properly [151, 160]. Clip rotation and kinking of the parent vessel can also be the result of uneven arterial walls due to atheromatous

*DOI: http://dx.doi.org/10.5772/intechopen.88038*

*Preventing Rupture: Clipping of Unruptured Intracranial Aneurysms DOI: http://dx.doi.org/10.5772/intechopen.88038*

have demonstrated clipping of UIAs is effective and has no mortality even in elderly [131], the risk of a poorer outcome increases in this age group, with higher instances of disability and death than endovascular procedures specifically in the presence of comorbidities [132, 136]. Retreatment of intracranial aneurysms is also associated with a higher mortality rate [146]. However, in our experience, clipping of solitary UIAs yields excellent results, with no mortality and a high degree of functional independence, as will be shown in a later subchapter.
