Characteristics of donor vessels and cerebral blood flow in the chronic phase after combined revascularization surgery for moyamoya disease

OBJECTIVE

This study aimed to analyze whether the development of donor vessels after combined revascularization surgery for moyamoya disease (MMD) is related to cerebral blood flow (CBF) changes.

METHODS

We retrospectively reviewed the charts of 11 adult (12 hemispheres) and 13 pediatric (19 hemispheres) patients who underwent combined revascularization in our department. The total vessel cross-sectional area (TVA) was the sum of the cross-sectional areas of the superficial temporal, middle meningeal, and deep temporal arteries imaged using time-of-flight magnetic resonance angiography. The ipsilateral relative CBF (RCBF) on the brain surface in the craniotomy area was calculated by single-photon emission computed tomography. ΔTVA and ΔRCBF were defined as the preoperative and postoperative ratios of TVA and RCBF, and their correlations were analyzed in adult and pediatric patients.

RESULTS

The TVA and RCBF showed a significant increase after surgery, regardless of the age group. However, there was no significant correlation between ΔTVA and ΔRCBF in either the adult or pediatric groups. While the adult group exhibited significantly higher ΔRCBF values compared to the pediatric group (p < 0.01, r = -0.44), the ΔTVA values were higher in the pediatric group compared to the adult group (p = 0.06).

CONCLUSIONS

In the chronic phase after combined revascularization surgery for MMD, the development of measurable TVA of donor vessels does not necessarily correlate with an increase in CBF around the craniotomy area.

Hemodynamic changes of donor artery after combined revascularization in adult Moyamoya disease

To explore the hemodynamic changes of the superficial temporal artery in adult Moyamoya Disease (MMD) who underwent combined revascularization surgery. A number of 40 patients with MMD were enrolled, and all of them underwent a direct superficial temporal artery (STA)-middle cerebral artery (STA-MCA) bypass combined with an encephalo-duro-arterio-synangiosis (EDAS). Hemodynamic parameters were detected by Color Doppler Ultrasonography (CDUS) at the preoperative, perioperative and follow-up time, including peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI). The control group were selected randomly during the same period. Researchers applied the SPSS 21 to conduct the two-sample analysis, Chi-Squared test and one-way repeated measures ANOVA between groups. P < 0.05 was considered statistically significant. In this study, 21 males and 19 females with an average age of 44.9 years (Range 28 y-56 y) were enrolled in the MMD group. Among them, 21 patients (52.5%) had perioperative complications, and all symptoms were transient neurological dysfunctions. Intermittent speech disorder was the most common complication during the period of operation. The preoperative hemodynamic of STA showed no significant difference between MMD and the control group. The perioperative hemodynamics had significant carnages compared with preoperative, and there was a trend of fluctuation. The perioperative PSV in the group with complications was significantly higher than the group without complications, except for EDV and RI. In the follow-up ( X ¯ = 5 months), PSV (60.21 ± 22.24 cm/s, P = 0.712) showed no difference compared with baseline data, while EDV (25.12 ± 9.94 cm/s, P = 0.000) and RI (0.575 ± 0.092, P = 0.000) showed significant difference between MMD and control group. The blood flow spectrogram showed high resistance in preoperative, but most patients showed a low resistance pattern during the follow-up time. It was the first time to demonstrate that the hemodynamic changes of STA fluctuated significantly within one week and eventually remained stable after combined revascularization. The PSV may play a more important role in postoperative complications. In the follow-up, PSV had no significant difference, EDV increased significantly, and RI decreased significantly. The blood flow spectrogram mainly shows a low resistance pattern when the hemodynamic is stable.

Complex Revascularization for Idiopathic Intracranial Occlusive Disease with Unruptured, Fusiform Anterior Cerebral Artery and Middle Cerebral Artery Aneurysms: 3-Dimensional Operative Video

Revascularization is an important strategy when treating cerebrovascular occlusive disease and complex aneurysms. Radial artery fascial flow-through free flaps (RAFFs) are flexible grafts that provide direct and indirect revascularization. RAFFs can be especially useful for large territory revascularization and can be combined with other direct bypasses. Although common in plastic and reconstructive surgery, RAFF neurosurgical applications have rarely been described. The 3-dimensional video presents a 47-year-old man with watershed infarcts on imaging who presented with right-sided weakness (Video 1). Vessel imaging was significant for bilateral internal carotid artery (ICA) terminus stenosis. The left middle cerebral artery (MCA) ended in a fusiform aneurysm of the M1 segment. The left anterior cerebral artery (ACA) also had a smaller fusiform aneurysm at the A1/2 junction. A perfusion study demonstrated an increased mean transit time in the left MCA territory. Given the patient's age, his symptomatic ischemia, and enlarging MCA aneurysm, he was recommended for a combined revascularization and left ICA occlusion. A left facial artery-to-MCA bypass using the right posterior tibial artery was performed for direct MCA revascularization. A left superficial temporal artery-to-ACA bypass with a RAFF was performed for direct ACA and indirect MCA territory revascularization. Postoperative angiography demonstrated patency of both direct grafts. The patient suffered small pericallosal infarcts because of retraction and perforator sacrifice at the revascularization site. At early follow-up, the patient was at his neurologic baseline, and at 1-year follow up, the patient had no additional infarcts on imaging and was living independently.

Large Scalp Defect Repair with Flap Reconstruction Using Tissue Expander After Combined Bypass in Case of Moyamoya Disease

BACKGROUND

Combined revascularization is the preferred surgical management of adult Moyamoya disease. However, postoperative flap necrosis of the scalp is not an uncommon complication. We investigated the role of scalp incision design on the basis of the course of the superficial temporal artery (STA) to prevent postoperative scalp necrosis. The utility of tissue expander in wide scalp defect repair is explored.

CASE DESCRIPTION

A 13-year-old female patient underwent STA-to-middle cerebral artery anastomosis and encephaloduroarteriosynangiosis due to ischemic symptoms. However, she suffered from wide scalp necrosis measuring 10.5 × 10 cm after bypass surgery. Conventional rotational scalp flap reconstruction was impossible due to the wide defect, and therefore split thickness skin graft was considered. However, aesthetic compromise or hair loss is a psychologic burden in an adolescent female. Two tissue expanders were inserted under the contralateral normal scalp, and a gradual expansion was achieved by saline infusion for 3 months. Finally, a wide scalp flap, which covered the large defect, was obtained using this procedure. The patient underwent rotational flap advancement and was discharged without any hair loss wound.

CONCLUSIONS

Miserable scalp flap design results in a large scalp defect during combined bypass surgery. However, tissue expanders aided the reconstruction of a large scalp defect. Reconstruction using tissue expanders and advancement of local rotation flap is recommended in case of large scalp necrosis. The procedure yields cosmetically superior outcomes due to scalp hair conservation and concealment of postoperative scar behind the hair line.

Novel Indirect Revascularization Technique with Preservation of Temporal Muscle Function for Moyamoya Disease Encephalo-Duro-Fascio-Arterio-Pericranial-Synangiosis: A Case Series and Technical Note

BACKGROUND

Direct and/or indirect bypass surgery is the established approach for preventing stroke in patients with moyamoya disease. However, conventional indirect revascularization, including encephalo-myo-synangiosis, has some disadvantages associated with the mass effect of the temporal muscle under the bone flap and postsurgical depression in the temporal region. We devised a novel indirect revascularization method, using only the temporal fascia, to address the aforementioned disadvantages.

METHODS

A skin incision was performed along the superficial temporal artery. The temporal fascia was cut such that the base of the fascia flap was on the posterior side. The fascia and temporal muscles were dissected separately. After turning over the fascia, the muscle was cut such that the base of the muscle flap was on the anterior side. Craniotomy, direct bypass, and encephalo-duro-synangiosis were performed conventionally. Only the temporal fascia was used for indirect revascularization and duraplasty. The muscle was replaced in the anatomically correct position after replacing the bone flap.

RESULTS

We performed the aforementioned surgery on 18 (13 women and 5 men) consecutive patients (21 cerebral hemispheres) enrolled between 2012 and 2016. The average age was 28.7 years. The mean follow-up period was 31.6 months. In 17 patients (94%), the symptoms and cerebral blood flow improved. Digital subtraction angiography showed satisfactory angiogenesis from the temporal fascia. Depression in the temporal region and atrophy of the temporal muscle were negligible.

CONCLUSIONS

This surgical technique provides good clinical and cosmetic outcomes. It may also be one of the good surgical treatments available for symptomatic moyamoya disease.

Clinical analysis of combined revascularization in treating ischemic Moyamoya disease in adults

OBJECTIVE

The aim of this study was to investigate the clinical efficacy of superficial temporal artery-middle cerebral artery anastomosis (STA-MCA)+encephalo-duro-myo-synangiosis (EDMS) in treating ischemic Moyamoya disease (IMD) in adults.

METHODS

A total of 30 adult patients with IMD were selected to be included in the study; they underwent STA-MCA+EDMS and were followed up for 3 months to 2 years. The digital subtraction angiography findings, modified Rankin scale (mRs) score, and complications of all the patients were compared.

RESULTS

Thirty patients successfully completed the surgery. Three patients had postoperative complications (two patients with cerebral infarction on the surgical side and one patient with poor scalp healing). The postoperative morbidity rate was 10%. Angiography conducted at 3 to 6 months postoperatively showed 28 cases of anastomotic patency; the anastomotic patency rate was 93.3%. The mRs scores of the patients' neurological function 3 months after surgery were lower than those before surgery.

CONCLUSION

STA-MCA+EDMS is effective in treating Moyamoya disease.