Yong Bae Kim, William L. Young and Michael T. Lawton
Parafalcine arteriovenous malformations (AVMs) have a midline plane in common, but differ in their location (anterior, middle, or posterior) and depth (superficial or deep). Surgical management varies with AVM location and depth in terms of patient position, head position, craniotomy, and surgical approach. This study examined surgical strategies, patient outcomes, and regional factors influencing results.
Patients with AVMs located on the medial surface of the cerebral hemisphere were identified retrospectively from a consecutive, single-neurosurgeon series that is registered prospectively as part of the UCSF Brain Arteriovenous Malformation Study Project. During a 12-year period, 443 patients with AVMs were treated surgically. Of these 443 patients, 132 (30%) had parafalcine AVMs, which were distributed in zones as follows: superficial-anterior, 25 (18.9%); superficial-middle, 26 (19.7%); superficial-posterior, 39 (29.5%); deep-anterior, 25 (18.9%); deep-posterior, 17 (12.9%). Five different surgical strategies were used depending on AVM zone.
Complete AVM resection was achieved in 123 (93.2%) of 132 patients. Overall, neurological condition improved in 74 patients (56.1%) and remained unchanged in 41 patients (31.1%). Neurological condition deteriorated in 12 patients (9.1%), and 5 patients (3.8%) died. Patients with AVMs in the superficial-middle zone had the highest rate of neurological deterioration (26.9%).
Parafalcine AVMs lie on a midline surface that, when exposed with a bilateral craniotomy across the superior sagittal sinus and a wide opening of the interhemispheric fissure, makes them superficial. However, unlike convexity AVMs, which are approached perpendicularly, parafalcine AVMs are approached tangentially. Gravity retraction is useful with deeply located AVMs (those in the deep-anterior and deep-posterior zones), because it widens the interhemispheric fissure and accesses deep arterial feeding vessels from the anterior and posterior cerebral arteries. Surgical risks were increased in the superficial-middle zone, which is likely explained by the proximity of sensorimotor cortex. The authors' regional classification of parafalcine AVMs may serve as a guide to surgical planning.
Joonho Chung, Sang Hyun Suh, Chang-Ki Hong, Jin-Yang Joo, Yong Cheol Lim, Yong Sam Shin and Yong Bae Kim
The purpose of this study was to report the authors' preliminary experience using self-expanding closed-cell stents deployed in small arteries (< 2 mm in diameter) to treat intracranial aneurysms.
A total of 31 patients were studied. All subjects met the following criteria: 1) they received an Enterprise stent for treatment of a wide-necked aneurysm or a dissecting aneurysm or as part of a stent-salvage procedure; and 2) they had an Enterprise stent deployed in a small parent artery (< 2 mm in diameter) that had no atherosclerotic stenosis. Procedure-related complications and follow-up sizes of the parent arteries were evaluated for safety and patency.
There were 16 ruptured aneurysms and 15 unruptured aneurysms. Three (9.7%) of the 31 patients experienced procedure-related complications, and they all were asymptomatic. Follow-up angiography was performed in 27 patients (87.1%) (at a mean 15.5 months after surgery). Parent arteries with 2 acute angles (n = 4) were occluded in 3 cases (75.0%), and those with no acute angles (n = 13) or 1 acute angle (n = 6) showed 100% patency on follow-up angiography. There was a significant difference between the follow-up sizes (mean 1.72 ± 0.30 mm) of parent arteries and their sizes (mean 1.59 ± 0.26 mm) before treatment (95% CI − 0.254 to − 0.009 mm; p = 0.037, paired-samples t-test).
In the current series the deployment of self-expanding closed-cell stents in small arteries was safe and resulted in good patency, especially when the stents were deployed in segments of the parent artery with no acute angles or only 1 acute angle.
Yeon Soo Choo, Joonho Chung, Jin-Yang Joo, Yong Bae Kim and Chang-Ki Hong
The purpose of this study was to determine predisposing factors for good clinical outcome in patients with spontaneous basal ganglia hemorrhage with borderline volumes (defined as a hematoma volume between 20 and 50 cm3) who had undergone treatment by stereotactic catheter drainage.
From the 298 patients whose information had been prospectively collected in the institutional database between January 2010 and December 2013, 93 patients were included in this retrospective study and divided into 2 groups: best medical treatment alone (Group A, n = 44) and best medical treatment plus catheterization (Group B, n = 49). All patients met the following criteria: 1) a diagnosis of spontaneous basal ganglia hemorrhage, and 2) a borderline hematoma volume (20 to 50 cm3). Postoperative modified Rankin Scale (mRS) scores and recovery of motor weakness were compared between the 2 groups, and predisposing factors for good clinical outcome were evaluated.
Patients in Group B showed earlier recovery of motor weakness and improved mRS scores than patients in Group A. The final mRS score at 12 months was better in Group B than in Group A (p = 0.006). Predisposing factors for a good clinical outcome were a hematoma volume < 30 cm3 (OR 6.158, 95% CI 1.221–31.053, p = 0.028), an initial Glasgow Coma Scale (GCS) score ≥ 13 (OR 6.331, 95% CI 1.129–35.507, p = 0.036), the absence of internal capsule involvement (OR 4.680, 95% CI 1.152–19.010, p = 0.031), and catheterization (OR 13.376, 95% CI 2.423–73.842, p = 0.003) based on logistic regression analysis.
Good clinical outcome can be expected after stereotactic catheter drainage in patients with a hematoma volume between 20 and 30 cm3, an initial GCS score ≥ 13, and the absence of internal capsule involvement. Among these patients, stereotactic catheter drainage may have a beneficial effect on early recovery of motor weakness and functional outcome, indicating that lateral-type basal ganglia hematoma compression not involving the internal capsule may be better treated using stereotactic catheter drainage than treated medically.
Waleed Brinjikji and Giuseppe Lanzino
Joonho Chung, Yong Cheol Lim, Sang Hyun Suh, Yu Shik Shim, Yong Bae Kim, Jin-Yang Joo, Bum-soo Kim and Yong Sam Shin
The purpose of this study was to report the authors' experiences in stent-assisted coil embolization (SAC) of ruptured wide-necked aneurysms in the acute period and to evaluate the incidence of and risk factors for periprocedural complications.
A total of 72 patients were recruited for this study between March 2007 and June 2012. All patients met the following criteria: 1) the presence of ruptured intracranial wide-necked saccular aneurysms, and 2) the patient underwent SAC for treatment of those aneurysms within 72 hours of rupture. All of the patients with clinically poor grades or acute hydrocephalus underwent external ventricular drainage (EVD) before SAC. The incidence of and risk factors for periprocedural complications were retrospectively evaluated.
Of the 72 patients included in this study, periprocedural complications occurred in 14 (19.4%), including asymptomatic complications in 4 (5.6%) and symptomatic complications in 10 (13.9%); there were symptomatic thromboembolic complications in 5 patients (6.9%), and symptomatic hemorrhagic complications in 5 (6.9%). The authors observed no subacute or delayed thromboembolic complications during the follow-up period of 18.8 months. Use of EVD (OR 1.413, 95% CI 0.088–2.173; p = 0.046) was the only independent risk factor for periprocedural complications on multivariate logistic regression analysis.
The periprocedural complication rate during SAC was 19.4% among 72 patients. Because of the high complication rate, microsurgical clipping or endovascular treatment with another technique (multiple-microcatheter or balloon-assisted technique) may be a more appropriate option for first-line treatment than SAC, especially in patients requiring EVD.
Kwang-Chun Cho, Jung-Jae Kim, Chang-Ki Jang, Chang-Ki Hong, Jin-Yang Joo and Yong Bae Kim
Rete middle cerebral artery (MCA) is extremely rare and has not been frequently discussed. Rete MCA is a weblike anomaly of the MCA that does not coalesce and forms a prominent, large single branch from the plexiform vessels in the fetal stage. The purpose of this study was to further elucidate the clinical and radiological characteristics of patients with rete MCA.
A total of 2262 cerebral digital subtraction angiography procedures were performed on 1937 patients at the authors’ institution from February 2013 to May 2017. Data analysis included age, sex, clinical symptoms, underlying diseases, coexisting cerebral arterial anomalies, and operative methods and findings.
Rete MCAs were found in 13 patients, and the incidence of this anomaly was 0.67% (13 of 1937) in this study. Of the 13 patients, 3 had hemorrhagic strokes, 6 had ischemic strokes, and 4 had no symptoms. Eight patients underwent conservative treatment, and 5 patients underwent surgical treatment. Rete MCA is considered a congenital disease of the cerebral vasculature with the possibility of an acquired abnormality, such as an aneurysm, caused by hemodynamic stress. Although an epidemiological survey of rete MCA was not conducted, it is assumed that rete MCA has a high prevalence in Asia. Ischemic and hemorrhagic stroke events are fairly common in rete MCA.
Clinicians should understand the radiological and clinical features of patients with rete MCA to avoid misdiagnosis and unnecessary treatment. This anomaly should be differentiated from other vascular diseases and patients presenting incidentally should be carefully monitored because of their vulnerability to both hemorrhagic and ischemic strokes.