Outcomes of Combined Revascularization Surgery for Moyamoya Disease without Preoperative Cerebral Angiography

Clinical application of color Doppler ultrasound for assessing hemodynamic changes in the children with moyamoya disease undergoing combined revascularization surgery

Objective

To investigate the advantages of color Doppler ultrasound (CDUS) in detecting hemodynamic alterations in children with moyamoya disease (MMD) following combined revascularization surgery.

Methods

The common carotid artery (CCA), internal carotid artery (ICA), external carotid artery (ECA), and superficial temporal artery (STA) were measured by CDUS. Hemodynamic parameters including arterial diameter, peak systolic velocity (PSV), resistance index (RI), and blood flow volume (FV) were collected at three time points: pre-operation (T1), one week after operation (T2), and three months after operation (T3). Twelve children without intracranial arterial disease were recruited as the control group. Matsushima classification-based on digital subtraction angiography (DSA) was applied at T2.

Results

Among the 12 children with MMD, 11 patients with bilateral arterial stenosis and 1 patient with unilateral being affected. Compared to the 24 control hemispheres, the diameter of the ICA was significantly smaller in the 23 MMD hemispheres (p < 0.001) with an increased PSV of CCA and ECA, and a decrease FV of carotid arteries (p < 0.05). In MMD group, CDUS revealed increased diameter and FV, decreased RI of STA at the operative side at T2. The PSV and FV of ECA at the operative side increased from T1 to T3 (p < 0.05). Six cases were allocated to satisfactory compensation group (S Group, Matsushima classification grade A and B) and six cases to dissatisfactory compensation group (DS Group, Matsushima classification grade C). The increase in FV of STA on the operative side was higher in S Group at T2 than DS Group (Spearman rho = -0.693, p = 0.039).

Conclusion

As a noninvasive imaging modality, carotid and superficial temporal arteries ultrasound may serve as a valuable adjunct to invasive imaging techniques for children with MMD.

Clinical Outcome and Surgical Outcome of Moyamoya Disease after Combined Revascularization Performed at the Neurological Institute of Thailand

Objective  Moyamoya disease is a chronic, progressive, intracranial steno-occlusive disease. Cerebral revascularization has proved that it is more beneficial than medical therapy for prevention of recurrent stroke. We aimed to report clinical and surgical outcome of moyamoya disease after combined revascularization in Thai population. Materials and Methods  From October 2015 to March 2023, patients diagnosed with moyamoya disease and were operated with combined revascularization were included. Patients were evaluated for hemodynamic state with preoperative and postoperative blood oxygenation level-dependent magnetic resonance (BOLD MR) imaging. Demographic data, serial imaging, surgical outcome, and clinical outcome were analyzed. Morbidity and mortality rates of surgery were reported. For clinical outcome evaluation, modified Rankin Scale (mRS) scores were compared between preoperative and postoperative outcome. The mRS score of 0 to 2 signify good outcome after surgery. Results  There were a total of 55 patients. Ischemic stroke was the most common presentation (87.3%). Based on the Suzuki's classification, most of the patients were stage 3 and 4. Clinical outcome measured with mRS score had good outcome, 100% (mRS score 0-2). For surgical outcome, overall graft patency was 94.8%, overall complication rate was 6.5%, and mortality rate was zero. Mean follow-up duration was 44.5 ± 25.1 months. Recurrent stroke occurred in 1.3%, which was recurrent ischemic stroke. Conclusion  Combined revascularization in moyamoya disease in the Thai population has a good clinical outcome, an acceptable risk of complication, and a reduced recurrent rate of stroke. Clinical and surgical outcome should be studied in the long term with the use of BOLD MR with carbon dioxide stimuli for the evaluation of cerebral blood flow in the patient.

Long-term Outcomes of Combined Revascularization Surgery for Moyamoya Disease in the Elderly: A Single Institute Experience

The opportunity to treat older patients with Moyamoya disease (MMD) is increasing. However, the surgical outcomes after combined direct and indirect revascularization for elderly patients with MMD are not fully understood, especially for those ≥60 years old. This retrospective study examined 232 consecutive hemispheres of 165 adults with MMD who underwent combined revascularization. Clinical features and surgical outcomes were compared between the elderly (≥60 years) and nonelderly group (<60 years). Thirteen (5.6%, 64.4 ± 4.0 years old) and 219 hemispheres (94.4%, 40.2 ± 10.8 years old) were included in the elderly and nonelderly group, respectively. The proportion of clinical presentations before surgery did not differ. However, the prevalence of hypertension and hyperlipidemia was significantly higher in the elderly group than in the nonelderly group. Meanwhile, hyperthyroidism was observed only in the nonelderly group. No significant intergroup differences were observed in the incidence of perioperative complications occurring within four weeks postsurgery. Notably, the elderly group was more prone to develop perioperative intracerebral hemorrhage (odds ratio (OR) 3.14, 95% confidence interval (CI) 0.45-13.5) than the nonelderly group. During a median follow-up period of 7.8 years, the incidence of stroke recurrence occurring later than four weeks postsurgery was not significantly different between the groups (hazard ratio, 1.19; 95% CI 0.133-10.6). The prevalence of independent outcomes (76.9% vs. 90.4%, P = 0.14) and mortality (7.7% vs. 1.4%, P = 0.21) did not differ significantly between the elderly and nonelderly groups, respectively. Perioperative intracerebral hemorrhage may be common in the elderly and should be considered to achieve a favorable surgical outcome.

Clinical Characteristics of Immediate Contralateral Ischemia Subsequent to Revascularization for Moyamoya Disease

BACKGROUND

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed.

METHODS

We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10 years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3 months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis.

RESULTS

The mean age was 34.5 (range: 5-71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429 G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44-71 years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF213 c.14429 G > A variant were patchy and peripheral. The other case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotid artery where patency had been confirmed preoperatively.

CONCLUSIONS

Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types.