3.1 Goals

1. 
   

   Review the literature of the management of ruptured cerebral aneurysms and understand the strengths and weaknesses of the respective landmark studies.

   
   
2. 
   

   Review the options for treatment of ruptured cerebral aneurysms including the merits of the different treatment strategies.

   
   
3. 
   

   Understand the factors which might favor one treatment modality over another.

3.2 Case Example

3.2.2 Treatment Plan

Given the patients intubated status and need for continued intubation/sedation for further evaluation, a right frontal ventriculostomy catheter was placed and the patient was transferred to the neurointerventional suite for angiography and consideration of open versus endovascular intervention.

In Fig. 3.3a, digital subtraction angiography showed an an-teromedially projecting 3-mm ACA aneurysm. Given the configuration of the lesion, coil embolization was chosen as a means of primary treatment. A single 2.5 mm * 4 cm coil was placed within the dome of the lesion with a small extraluminal loop of coil noted at the termination of the coil embolization. Follow-up angiography demonstrated slight persistent filling within the coil interstices and the base of the lesion consistent with a modified Ray-Royce classification 3a closure (Fig. 3.3b, c).

Hospital course: Following embolization, the patient was transferred to the neurological intensive care unit for close monitoring. There, she was extubated and maintained on oral Nimodipine. Her external ventricular drain (EVD) was clamped on post-bleed day 2 and removed on post-bleed day 3. On post-bleed day 8, she was noted to have elevated transcranial Doppler values and clinical changes with agitation and confusion. An angiogram demonstrated moderate-to-severe anterior cerebral artery vasospasm bilaterally, which was treated with intra-arterial verapamil. Aneurysm closure improved to mRRC2 on follow-up angiography. She had postprocedural improvement in her mental status and was transferred to rehabilitation on post-bleed day 20.

3.3 Case Summary

1. 
   

   What is the time course for the treatment of this lesion? Historically ruptured aneurysms were managed conservatively, and the lesion secured only after some recovery from the initial hemorrhage. ^{1 , 2} This evidence predated modern microsurgical and endovascular strategies, and thus, the intervention had to be weighed considering intervention in face of a swollen cortex and the risk of secondary injury from surgery. More recent evidence suggests that the risk of poor outcomes and delayed cerebral ischemia is higher for lesions treated further removed from rupture. ^{3 , 4} This, in addition to the ongoing rupture risk following primary rupture, supports treatment within 24 to 48 hours of patient presentation. ⁵

   
   
2. 
   

   What patient factors are considered when selecting an approach?

   
   

   Our patient is a young female who presented with a moderate-grade clinical presentation, HH3, and WFNS IV. When considering open versus endovascular intervention options, consideration is given to the possible complications associated with either treatment modality. The International Subarachnoid Aneurysm Trial (ISAT) demonstrated improved cognitive outcomes with fewer complications in those patients treated with endovascular occlusion compared to open surgical clipping. ⁶ Further, the brain retraction of acutely injured brain needed for open surgical clipping must be weighed against the ischemic risk of catheterization and coil embolization. ² On the other hand, the durability of treatment must be considered, given the patient’s young age. Surgical clipping, when performed successfully, has a near permanent durability, while endovascular occlusion has a more variable longevity and requires extended clinical and radio-graphical follow-up. ^{4 , 7}

   
   

   Our patient is relatively young with minimal cortical atrophy and evidence of cortical injury. In these instances, when technically feasible, we employ a coil-first approach as demonstrated in Fig. 3.3 with the primary goal of “aneurysm rebleed protection” and the secondary goal of aneurysm occlusion. ⁸ This is performed with the knowledge that after recovering from their initial injury, permanent occlusion can be achieved with either the use of adjunctive endovascular devices or surgical clipping.

   
   
3. 
   

   What aneurysm factors are considered in devising a treatment strategy?

   
   

   At presentation, a CT angiogram of the head and neck is obtained, which informs the decision regarding the optimal means of treatment. Variables relevant to endovascular intervention, such as aortic arch, cervical, and intracranial anatomy, can be preliminarily assessed. Further, aneurysmal orientation and factors, such as rupture site with respect to aneurysm orientation, accessibility and exposure of aneurysm and aneurysm neck, can be assessed. After this preliminary information, our institution performs an angiogram with 3D angiography to assess, in detail, the aneurysm anatomy to fully evaluate the merits of an endovascular versus an open approach, unless the clinical conditions require more immediate open surgical intervention.

   
   

   Our patient has a small 2-mm aneurysm with a dome-to-neck aspect ratio of< 2 arising from the left ACA junction which projects medially and anteriorly. ^{9 , 10} Although the anterior projection of the lesion indicates this lesion could be addressed with low risk to ACA perforators and the contralateral A2, a left-sided, dominant hemisphere approach would be necessary in order to achieve proximal control. ¹¹ The 3D angiography indicated that the neck may be smaller than demonstrated on 2D projections; thus, primary coiling was selected as the optimal means for approaching the lesion.

   
   
4. 
   

   Do adjunctive devices play any role in endovascular occlusion of this patient?

   
   

   Our patient’s lesion does have a mid-range dome-to-neck aspect ratio; thus, adjunct devices could be entertained to assist with treatment. Balloons are often used as both a means to assist coil placement in wide-necked aneurysms and as a safety measure to achieve control should intraproce-dural rupture occur. Our practice does not typically use these devices on lesions we perceive to be primarily treatable with coils without the use of a balloon because of the extra thrombogenic risk of an additional requisite catheter. ^{12 , 13} Similarly, we typically do not employ stents for the treatment of ruptured lesions, choosing to either use balloon assistance, achieve only dome protection, or alternatively pursue open surgical clipping. This is primarily secondary to the risk of loading a patient with acute hemorrhage on dual antiplatelet therapy, which can lead to both ischemic and hemorrhagic complications. ^{14 , 15} Thus, despite mounting literature supporting the acute use of these devices, we presently do not use them routinely unless primary coiling is unachievable and surgical clipping too difficult. ^{16 , 17}

   
   
5. 
   

   How should the patient be followed posttreatment? Following the placement of a single coil, filling was no longer visualized at the dome of the lesion consistent with an mRRC3a grading and dome protection. ¹⁸ Rather than risking coil dislodgement or rupturing the lesion with recatheteriza-tion to achieve a higher packing density, no further coils were added. ¹⁹

   
   

   Reassurance of the aneurysm’s progressive closure was visualized on the patient’s vasospasm treatment study. As a protocol, patients are followed up with angiography at 6 months and then interval follow-up is determined based on the stability of the lesion. With a good RRC1 occlusion, we would then repeat angiography at 1.5, 3, and 5 years after which MRA would be used to follow the lesion over time. ¹⁸ This follow-up also ensures screening for the 5 to 10% risk of development of a de novo aneurysm. ²⁰