INTRODUCTION

 

Aneurysmal Subarachnoid Hemorrhage (SAH) has a 30-day mortality rate of 45%, with approximately half of the survivors sustaining irreversible brain damage. Intracranial saccular aneurysms represent the most common etiology (80%) of nontraumatic SAH. The international Subarachnoid Aneurysmal trial (ISAT) which compared endovascular treatment with aneurysm surgery in 2143 patients found that EVT had a significant better outcome as 76% of the patients who underwent endovascular treatment were surviving independently after 1 year, whereas 69% of the patients who were allocated to neurosurgical treatment were independent¹.

The present study was done to study morphology of ruptured cerebral aneurysms and to detect the efficacy of endovascular treatment using detachable coils as a new method for treatment of cerebral aneurysms.

 

SUBJECTS AND METHODS

 

Thirty two patients with SAH were admitted to Neuropsychiatry department at Suez Canal University hospital from June 2005 to November 2007. Of those patients with SAH, 24 patients were selected for endovascular coiling at catheterization unit of Diabetes Institute at Cairo.

The patient selection criteria for coil embolization included a clearly recognized aneurysm neck separate from the surrounding vessels. The exclusion criteria included Hunt and Hess grade V and patients with cerebral aneurysms > 25 mm. All procedures were performed under general anesthesia and systemic heparinization. Systemic heparinization was stopped at the end of the procedure in all patients. The standard endovascular technique was performed if a satisfactory embolization result could be expected.

All procedures were performed with the patient generally anesthetized by thiopental sodium, on a monoplane C-arm angiographic system without 3-dimensional reconstruction. Systemic heparin sodium was administered as an intravenous bolus of 50 IU per kilogram of body weight, and then it was infused continuously to maintain an activated partial thromboplastin time of at least three times the normal level throughout the procedure². The transfemoral approach and digital subtraction angiography with "road mapping" capability were used in all cases. If more than one aneurysm was found, the symptomatic one was treated first. Symptomatic aneurysm was determined according to the distribution of blood in the CT scan, presence of focal vasospasm, and size of the aneurysm, multi-lobed aneurysm and presence of daughter aneurysm. The proximal parent artery (internal carotid or vertebral artery) was catheterized with a No. 6 French nontapered polyethylene guiding catheter. A microcatheter was advanced coaxially into the aneurysm sac with the aid of a micro-guidewire. Guidewire was removed once the microcatheter tip was inside the aneurysm sac in order to void aneurysm perforation.

The detachable coils are introduced into the microcatheter with the aid of a special introducer. It is then advanced through the microcatheter into the sac of the aneurysm. Inside the microcatheter, the coil maintains a straight shape. When the coil emerges from the tip of the microcatheter, it conforms to the aneurysm lumen without causing aneurysmal wall distortion. It adopts a circular or 3 dimension formation and folds upon itself, conforming to the shape of the aneurysm and decreasing the possibility of trauma to its walls.

Angiography is always performed before detachment in order to demonstrate the relationship of the coil to the sac of the aneurysm and parent artery. The intrinsic radiopacity of the coils made from platinum or nitinol delineates their position very clearly, allowing an exact evaluation of its location before electrical detachment occurs. Detachment of the coil can be done electrically or mechanically.

It's possible to introduce, deliver, and detach more than one coil in the aneurysm, depending on the size of the lesion. If an undesirable placement of the coil results, it is possible to retrieve it before detaching the coil and to reposition it in more desirable location. We used many types of available coils, and are selected for use depending upon the aneurysm anatomy.

Adjunctive techniques such as balloon-remodeling or stent assisted coiling techniques were used for aneurysms with wide neck or branch arises from the neck³. Follow up of the treated patients for 2-4 weeks at hospital for complications of SAH. Modified Rankin Scale was applied at discharge 2-4 weeks after coiling and 6 months after coiling. Follow up of the patient monthly for 6 months for detection of rebleeding and hydrocephalus.

Follow up cerebral angiography by DSA after 6 months of the procedure was done for assessment of the stability of the aneurysm occlusion, this was graded as follow: no recurrence (when the neck and sac were completely occluded), neck remnant (residual contrast material filling the aneurysmal neck), and incomplete occlusion (persistence of residual opacification in the aneurysm sac or residual contrast filling the aneurysmal body)⁴.

 

Data Analysis

The process of data analysis and processing consisted of the following: All collected data were encoded; these codes entered into computer through Statistical Package for Social Science (SPSS) version 11.

1.      Data presented as mean, standard deviation or percentages.

2.      Chi-square test used for categorical variables and students t-test for continuous variables.

3.      Frequencies were used to examine the distribution of responses for all the variables and to describe sample demographics. The association between variables was examined by cross tabulations and the statistical significance of such relationships examined by chi-squared analysis.  

 

RESULTS

 

The 24 patients were 14 males and 10 females. Their age ranged between 15 years to 82 years with a mean of 46.17±16.35 years. Risk factors included for those ruptured aneurysms were hypertension in 12 patients, smoking in 8 patients, diabetes mellitus in 3 patients and ischemic heart disease in 1 patient (Table 1).

The 24 patients with aneurysmal SAH were classified according to Hunt and Hess scale, grade I-II in 8 patients (33.3%) had, grade III in 13 while IV in  3 patients (Table 2).

Simple coiling was done in 17 (68%) of the aneurysms, stent assisted coiling to prevent bulging of coils outside wide neck aneurysms was used in 6 aneurysms (24%), while balloon remodeling and coiling to temporarily occlude the wide neck aneurysms was done in 2 aneurysms (8%) (Table 3).

We succeeded to achieve total occlusion of the aneurysm in 23 aneurysms (92%), neck remnant was left in 1 aneurysm (4%) and incomplete occlusion was in (4%) (Table 4). We faced 1 clinical (4%) complication during the procedure due to branch occlusion (thrombus formation).  The outcome was good (mRS 0-2) in 21 patients (87.5%), moderate disability (mRS 3) in 1 patient (4.2%). Two patients died (mRS 6), the 1st one died 5 days after coiling due to severe vasospasm and complications of SAH unrelated to coiling, the other one died 7 days after coiling due to severe chest infection and metabolic complications. No patient had moderately severe (mRS 4) or severe disability (mRS 5) (0%).

There was a significant correlation between conscious level of the patients with SAH on admission assessed by H & H scale and their outcome assessed by mRS on discharge after coiling of aneurysms. All the patients who were H & H I-II (8 patients) & H&H III (13 patients) returned to completely normal function mRS 0-1. While patients who were H & H IV (3 patients on admission), two of them died due to complications of SAH, while the other one (4.3%) had moderate disability on discharge mRS 3  (Table5).

The results of follow up cerebral angiography after 6 months revealed that 21 (91.4%) of aneurysms had no recanalization, while 1 (4.3%) showed partial recanalization, 1 (4.3%) showed stable neck remnant with no need for further treatment. On the other hand no one of the patients (0%) had rebleeding during follow up for 6 months after coiling. the results of follow up of the patient condition assessed by mRS 6 months after discharge, 19 patients (86.5%) were grade 0 (no symptoms), 1 patient (4.5%) was grade 1 (no significant disability despite symptoms), 1 patient (4.5%) was grade 2 (slight disability) and 1 patient (4.5%) was grade 3 (moderate disability). The relation between size and outcome was not statistically significant at 95% level of confidence.

 

Table 1. Description of the sociodemographic data and risk factors (n=24).

 

 

Table 2. Severity of clinical picture using Hunt and Hess scale (n=24).

 

 

Table 3. Frequency distribution of techniques in coiling of aneurysms (n 25).

 

 

Table 4. Immediate angiographic outcome in the studied aneurysms (n=25).

 

 

Table 5. The relationship between conscious level of the patients before coiling assessed by H & H scale and their outcome assessed by mRS after coiling. 

   

*   mRS (0 no symptoms, 1 no significant disability, 2 slight disability, 3 Moderate disability, 4 Moderately severe disability, 5 Severe disability, 6 Dead)

* Chi-square = 0.1        p=0.012              * The test is statistically significant at 95% level of confidence

Illustrative cases

Case (1): 26 years old male patient had no history of HTN, DM, or smoking. He come complaining of headache and vomiting with disturbed conscious level O/E. Temp 37.5, B.P 140/90, H & H 3, No cranial nerve affection, no weakness and no sensory manifestations. Signs of meningeal irritation were present in the form of neck stiffness, +ve kerning’s sign. CT Brain showed SAH. Fisher scale 4, DSA showed Anterior communicating (Acom) aneurysm 4mm size, Simple coiling was done using 3 coils, Follow up showed no recanalization.

 

 

Figure 1. a. CT brain shows subarachnoid hemorrhage in falx cerebri. b. Anterior

communicating aneurysm 4 mm before coiling. The aneurysm before (c) and after (d) coiling

 

Case (2): 20 years old male patient, No HTN, DM or cigarette smoking. Complaining of headache, Rt. hemiparesis, Lt. partial 3^rd n. Palsy, H & H 3, Fisher 1, DSA showed Lt. Post. Cerebral aneurysm, wide neck, no vasospasm. A self expandable flexible stent was placed in front of the aneurysm neck then through the mesh of the stent a microcatheter was advanced into the aneurysm and coiling was performed. The presence of the stent prevented bulging of the coils out from the aneurysm and dense packing could be achieved. Owing to stopping the pulsatile flow in the aneurysm after filling its lumen followed by its fibrosis and shrinkage, the mass effect gradually improved over the next 3 months.

 

 

Figure 2. a. CT brain shows hyperdense area at the midbrain area. b. Digital subtraction angiography shows left posterior cerebral aneurysm 15 mm before coiling. c. Posterior cerebral aneurysm coiled with stent assistance. d. Detachable coils inside the aneurysm supported by nitinol stent.

 

 

DISCUSSION

 

If the aneurysm is left without treatment, the cumulative rate of rebleeding at 14 days is 27.7%, as reported by Juvela⁵, but the risk without intervention is increased to 35-40% in the 4th week after the first day of SAH⁶. Therefore, urgent occlusion of the bleeding aneurysm should be done⁷. Patients in poor clinical condition (Hunt and Hess grade 5) after SAH have historically fared poorly and many often were excluded from aggressive treatment. Raymond et al.⁸ and Kazekawa et al.⁹ found that the clinical and angiographic results were acceptable in patients with Hunt and Hess grades of 0 to 3. Thus patients who were H & H (IV) were excluded from our study.

We occluded 17 (68%) aneurysms with coils alone. The goal of cerebral aneurysmal embolization with coils is to exclude the aneurysm from normal circulation. Therefore, we occluded aneurysms and packed them with coils as densely as possible to prevent blood from entering the residual cavity and reopening the aneurysms.^3,9 proved that endovascular treatment was performed safely in patients with small and narrow-necked aneurysms, regardless of their age and physical condition. However, good packing in wide necked aneurysms faced the risk of extrusion of coil to blood stream.

Li et al.³ described that stent-assisted coil packing and balloon-remodeling techniques can be used in wide-necked aneurysms safely. Self-expandable, flexible nitinol stent assisted coiling was used with 6 cases (24%). Balloon remodeling with coiling was used in our study with 2 (8%) wide neck aneurysms. Balloons are used to provide temporary parent vessel protection during packing the aneurysm particularly when branch from the neck is needed to be saved.

We experienced one (4%) thromboembolic complication with occlusion of the parent artery, the patient was treated with direct local injection of gp IIb/IIIa blocker which resulted in partial recanalization. In the same direction, Gallas et al.¹⁰, showed that the most frequent complications experienced were thromboembolic events (5.2%) and ischemic complications at the time of treatment with transient or permanent neurological deficit.

We succeeded to achieve total occlusion of the aneurysm in (92%) of the treated aneurysms, neck remnant was left in (4%), and incomplete occlusion was done in one aneurysm (4%). After 6 months, 21 (91.4%) of aneurysms had no recanalization, while 1 (4.3%) showed partial recanalization and 1 (4.3%) showed stable neck remnant, but the clinical relevance of neck remnant is likely to be low as there was no observable recurrence of bleeding from these nearly completely occluded aneurysms¹¹. Previously reported series showed that total occlusion ranged from 68% to 74%.^12,9 Similarly Grunwald et al.¹³ described that 90% of aneurysms who were initially occluded 100% remained totally occluded and 3% showed neck regrowth while 7% showed partial occlusion but most of them occluded spontaneously.

After 6 months of follow up, there was no rebleeding for any of the treated  patients involved in this study. Similarly to Cognard et al.¹⁴, who followed patients for 3-20 months.

In conclusion endovascular coil treatment of ruptured aneurysms is an effective and safe technique in the occlusion of cerebral aneurysms from either anterior or posterior circulation. 

 

[Disclosure: Authors report no conflict of interest]

 

REFERENCES

 

1.        Dippel DWJ. Surgical treatment of ruptured intracranial aneurysms, J Neurol Neurosurg Psychiatry. 2003; 74: 1605-6.

2.        Vallée J, Aymard A, Vicaut E, Mauro Reis M, Merland J.  Endovascular Treatment of Basilar Tip Aneurysms with Guglielmi Detachable Coils: Predictors of Immediate and Long-term Results with Multivariate Analysis—6-year Exp Radiol. 2003; 226: 867-79. 

3.        Li MH, Gao BL, Fang C, Gu BX, Cheng YS, Wang W, et al. Angiographic Follow-Up of Cerebral Aneurysms Treated with Guglielmi Detachable Coils: An Analysis of 162 Cases with 173 Aneurysms. Am J Neuroradiol. 2006; 27: 1107-12.

4.        Molyneux A, Kerr R, Stratton I, Sandercock P, Clarke M, Shrimpton J, et al. International Subarachnoid Aneurysm Trial (ISAT), of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomized trial. Lancet. 2002; 360: 1267-74.

5.        Juvela S. Rebleeding from ruptured intracranial aneurysms. Surg Neurol. 1989; 32: 323-6.

6.        Hijdra A, van Gijn J, Stefanko S, Van Dongen KJ, Vermeulen M, Van Crevel H. Delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage: clinicoanatomic correlations. Neurology. 1986; 36: 329-33.

7.        Yamada S, Koizumi A, Hiroyasu I, Yasuhiko W, Watanabe Y, Chigusa D, et al. Risk Factors for Fatal Subarachnoid Hemorrhage. Stroke. 2003; 34: 2781.

8.        Raymond J, Guilbert F, Weill A, Georganos SA, Juravsky L, Lambert A, et al. Long-Term Angiographic Recurrences After Selective Endovascular Treatment of Aneurysms With Detachable Coils. Stroke. 2003; 34: 1398.

9.        Kazekawa K, Tsutsumi M, Aikawa H, Iko M, Tanaka A, Go Y, et al. Endovascular Treatment of Anterior Cerebral Artery Aneurysms using Guglielmi Detachable Coils: Mid-term Clinical Evaluation. Radiat Med. 2002; 20(6): 291-7.

10.     Gallas S, Pasco A, Cottier J, Gabrillargues J, Drouineau J, Cognard C, et al. A Multicenter Study of 705 Ruptured Intracranial Aneurysms Treated with Guglielmi Detachable Coils. Am J Neuroradiol. 2005; 26: 1723-31.

11.     Sluzewski M, van Rooij WJ, Rinkel GJ, Wijnalda D. Endovascular Treatment of Ruptured Intracranial Aneurysms with Detachable Coils: Long-term Clinical and Serial Angiographic Results. Neuroradiology. 2003; 100: 857-999.

12.     Vinuela F, Duckwiler G, Mawad M. Guglielmi detachable coil embolization of acute intracranial aneurysm: perioperative anatomical and clinical outcome in 403 patients. J Neurosurgery. 1997; 86(3): 475-82

13.     Grunwald IQ, Papanagiotou P, Struffert T, Politi M, Krick C, Gül G, et al. Recanalization after endovascular treatment of intracerebral aneurysms. Neuroradiology. 2007; 49(1): 41-7.

14.     Cognard C, Weill A, Spelle L, Piotin M, Castaings L, Rey A, et al. Long-term angiographic follow-up of 169 intracranial berry aneurysms occluded with detachable coils. Radiology. 2006; 212(2): 348-56.