Treatment of unruptured intracranial aneurysms
Since the 1990s, the treatment of intracranial aneurysms has entered the era of microinvasiveness and has made great progress. Due to the advancement of neuroimaging, the detection rate of unruptured intracranial aneurysms has increased accordingly, but there are still different opinions on the treatment. From October 1991 to September 2002, a total of 332 cases of intracranial aneurysm were admitted to our department, among which 58 cases of unruptured intracranial aneurysm were treated as follows.
Clinical data
1.General information and classification
There were 58 patients with unruptured intracranial aneurysm in this group, including 25 males and 33 females, aged 19-71 years old, with an average of 46.2 years old. They can be divided into three categories: 1) aneurysm without rupture but with clinical symptoms, called symptomatic aneurysm (32 cases); 2) incidental aneurysm found during cerebral angiography for other reasons, called incidental aneurysm (7 cases); 3) one of the multiple aneurysms ruptured, and DSA found another aneurysm that did not rupture. There are also unruptured aneurysms, which are called unruptured aneurysms in multiple aneurysms, 19 cases in total.
2. Symptomatic aneurysm
(1) Clinical manifestations: The main manifestations were cranial nerve compression symptoms, including visual acuity loss in 6 cases, visual field defects in 4 cases, ocular motility disorders in 19 cases, and cranial nerve dysfunction in the posterior group in 2 cases. There were 4 cases of mild hemiparesis, 6 cases of vertebral fasciculus sign, and 2 cases of cerebellar symptoms.
(2) Examination: DSA examination was performed in all patients, and 17 cases of aneurysm of the cavernous sinus segment of the internal carotid artery, 9 cases of paracentral carotid artery aneurysm, 3 cases of middle cerebral artery aneurysm and 3 cases of vertebral artery aneurysm were found. The maximum diameter of the aneurysm was 1.5-2.5 cm in 13 cases, and >2.5 cm in 19 cases. All patients underwent CT and MRI examinations. 23 cases had aneurysms visible on CT and all cases had aneurysms detected on MRI.
(3) Treatment: 13 cases were treated surgically, including 8 cases of paracentral carotid aneurysm, 3 cases of middle cerebral aneurysm and 2 cases of vertebral aneurysm. There were 15 cases of neurointerventional treatment, including 14 cases of internal carotid artery occlusion for aneurysm of the cavernous sinus segment of the internal carotid artery, and 1 case of GDC embolization for paracentral carotid aneurysm of the bed process. Four cases aged over 70 years were observed, including three cases of aneurysm of the cavernous sinus segment of the internal carotid artery and one case of vertebral artery aneurysm.
3. Incidental aneurysm
(1) Clinical manifestations: This group of patients had no symptoms related to aneurysm, but all of them found aneurysm incidentally when they underwent MRI or DSA examination for other reasons. The reasons for the examination were headache in 3 cases, spontaneous bleeding in the brain in 2 cases, intracranial tumor in 1 case, and epilepsy in 1 case.
(2) Examination: 2 cases were examined by MRI and found to be large aneurysms of the internal carotid artery and middle cerebral artery, respectively. The remaining 5 cases were examined by DSA, and the aneurysms were found to be located in the anterior communicating artery in 2 cases, the posterior communicating artery in 2 cases, and the middle cerebral artery in 1 case.
(3) Treatment: One case was treated surgically because the giant aneurysm of middle cerebral artery found by MRI was misdiagnosed as a tumor and directly removed surgically. Neurointerventional treatment was performed in 3 cases, including GDC embolization of posterior communicating artery aneurysm in 2 cases and anterior communicating artery aneurysm in 1 case. Among the remaining 3 cases, 1 case of giant aneurysm of internal carotid artery aged more than 60 years was observed, and the other 2 cases of aneurysm patients refused treatment.
4. Unruptured aneurysms in multiple aneurysms
(1) Clinical manifestations: All patients showed subarachnoid hemorrhage, including 3 cases of combined arterial nerve palsy and 1 case of mild hemiparesis, all caused by ruptured intracranial aneurysm. The unruptured aneurysm was asymptomatic.
(2) Examination: 9 patients underwent 3D-CTA examination, and both ruptured and unruptured intracranial aneurysms were found. DSA was performed in all patients. The ruptured aneurysm was located in the posterior communicating artery in 11 cases, among which the combined unruptured aneurysm was located in the internal carotid artery next to the ipsilateral bed process in 1 case, the bifurcation of the ipsilateral internal carotid artery in 1 case, the ipsilateral anterior choroidal artery in 1 case, the contralateral posterior communicating artery in 4 cases, the anterior communicating artery in 2 cases, and the ipsilateral and contralateral middle cerebral artery in 1 case. The ruptured aneurysm was located in the anterior communicating artery in 6 cases, among which the combined unruptured aneurysm was located in the cavernous sinus segment of the internal carotid artery in 1 case, the posterior communicating artery in 3 cases, and the middle cerebral artery in 2 cases. The ruptured aneurysm was located in the middle cerebral artery in 2 cases, of which 1 case was combined with each of the anterior and posterior communicating arteries.
(3) Treatment: Six cases were treated surgically, and the ruptured posterior communicating artery aneurysm was clamped in all of them, and the unruptured aneurysm was clamped in four cases, including one case each of the ipsilateral paracentral carotid artery, internal carotid artery bifurcation, anterior choroidal artery and middle cerebral artery. In the other 2 cases, the unruptured aneurysm was a contralateral posterior communicating artery aneurysm, which was left untreated for clinical observation. Neurointerventional treatment was performed in 13 cases, all of which used GDC to embolize the ruptured aneurysm, including 10 cases of unruptured aneurysm with GDC embolization at the same time, including 6 cases of posterior communicating aneurysm, 2 cases of anterior communicating aneurysm, and 2 cases of middle cerebral aneurysm. The remaining 3 unruptured aneurysms were located in the cavernous sinus segment of the internal carotid artery, the anterior communicating artery and the middle cerebral artery, and were observed because they were too severe and the aneurysms were not suitable for embolization treatment.
Treatment results
Of the 32 cases in the symptomatic aneurysm group and 13 cases treated surgically, 9 had excellent results, 2 had moderate disability, 1 had severe disability, and 1 had death. One case of giant vertebral artery aneurysm died due to brainstem ischemia after surgery. Neurointerventional treatment was performed in 15 cases with excellent results and no related complications. In the 4 cases observed clinically, there were no significant changes during the mean follow-up of 3.7 years.
Of the 7 cases of incidental aneurysm, 1 case of giant aneurysm of the middle cerebral artery had hemiparesis after surgery, and all 3 cases of neurointerventional treatment recovered well. The remaining 3 cases were untreated and had no clinical symptoms during the 2.3 years of follow-up.
Among the unruptured aneurysms of multiple aneurysms, there were 19 cases. 4 of the 6 cases in the surgical group had both ruptured and unruptured aneurysms clamped, 3 cases recovered well after surgery, and 1 case had mild disability. 2 cases had untreated unruptured aneurysms and were lost to follow-up after 4 years of clinical observation. Among the 13 cases in the neurointerventional group, 10 cases had both ruptured and unruptured aneurysms embolized, 7 cases had good postoperative recovery, 1 case had mild disability, 1 case had moderate disability, and 1 case had severe disability. One of them had bleeding after 5 days and was embolized by GDC again, and the patient was severely disabled. The other two cases were followed up for 1.9 years, one case recovered well and the other case was in severe disability.
Discussion
Since the 30-day mortality rate for aneurysmal SAH is 45%, it is reasonable to consider treatment of UIAs before rupture. However, surgical treatment and embolization are not without risks. There is a debate whether patients with UIAs should be treated conservatively or with early surgical management. Our group of 58 patients with UIAs can be divided into three categories: 1) symptomatic aneurysms in 32 cases; 2) incidental aneurysms in 5 cases; and 3) multiple aneurysms, one of which ruptured and an additional unruptured aneurysm in 14 cases. the UIAs international study reported aneurysm diameters.