Cerebral glucose metabolism changes in chronic ischemia patients following subcranial-intracranial bypass.

The use of the internal maxillary artery (IMA) in intracranial artery bypass or subcranial-intracranial (SC-IC) bypass has recently been described as an alternative to traditional bypass. This study explores cerebral glucose metabolism characteristics of SC-IC bypass. Ten crescendo transient ischemic attack (TIA) patients with chronic occlusion of the middle cerebral artery (MCA) received bypass surgery of IMA with the radial artery graft (RAG) to the branch of MCA. The graft's flow volume (FV) was measured by operative intraoperative duplex ultrasonography. Positron emission tomography (PET)/computed tomography (CT) was used to calculate the preoperational and postoperational average of the standard uptake value (SUVavg) of the 18-fluoro-2-deoxy-D-glucose (18F-FDG) in the region of interest (ROI). The asymmetric index (AI) is recommended to reflect the SUVavg changes, and subsequently, cerebral glucose metabolism changes are supposedly clarified. Patent IMA-RAG-MCA bypass in ten chronic ischemia patients was confirmed by angiography after surgery. The intraoperative FV measurement value was 65.64 ± 10.52 (58.11-73.17) ml/min. Before the operation, the SUVavg of the ROI in the ischemic hemisphere (4.76 ± 2.35 (3.08-6.04)) clearly decreased compared to the one (5.99 ± 2.63 (4.11-7.87)) in the contralateral mirror region (P = 0.003). The result of AI of preoperation minus AI of postoperation was more than 10% (P = 0.031), which indicated suspicious significant changes in cerebral metabolism. All symptoms of study patients having crescendo ischemia were resolved in 1 month after the operation. In the cerebral hypoperfusion territory, uptake of 18F-FDG deceased. Improving the flow volume via SC-IC bypass makes available an elevated uptake of 18F-FDG.

Measurement of Blood Flow in an Intracranial Artery Bypass From the Internal Maxillary Artery by Intraoperative Duplex Sonography.

This study explored the hemodynamic characteristics of a subcranial-intracranial bypass from the internal maxillary artery by measuring blood flow on intraoperative duplex sonography. The hemodynamic parameters of the internal maxillary artery (n = 20), radial artery (n = 20), internal maxillary artery-middle cerebral artery bypass (n = 42), and internal maxillary artery-posterior cerebral artery bypass (n = 9) were measured by intraoperative duplex sonography. There was no significant difference in the internal diameters of the internal maxillary and radial arteries (mean ± SD, 2.51 ± 0.34 versus 2.56 ± 0.22 mm; P = .648). The mean radial artery graft length for subcranial-intracranial bypasses was 88.5 ± 12.78 mm (95% confidence interval [CI], 80.8-90.2 mm). Internal maxillary artery-middle cerebral artery bypasses required a shorter radial artery graft than internal maxillary artery-posterior cerebral artery bypasses (77.8 ± 2.47 versus 104.8 ± 4.77 mm; P = .001). The mean flow volumes were 85.3 ± 18.5 mL/min (95% CI, 76.6-93.9 mL/min) for the internal maxillary artery, 72.6 ± 26.4 mL/min (95% CI, 64.3-80.9 mL/min) for internal maxillary artery-middle cerebral artery bypasses, and 45.4 ± 6.7 mL/min (95% CI, 40.7-50.0 mL/min) for internal maxillary artery-posterior cerebral artery bypasses. All grafts were opened after the success of the salvage procedures had been established, and the early patency rates (1 month after the operation) were 95% for internal maxillary artery-middle cerebral artery bypasses and 100% the internal maxillary artery-posterior cerebral artery bypasses. Measurement of blood flow by intraoperative sonography can be helpful in decision making and predicting graft patency and success after neurosurgical bypass procedures.

A comparison of haemodynamics between subcranial-intracranial bypass and the traditional extracranial-intracranial bypass.

BACKGROUND: Ischemic cerebrovascular diseases are traditionally treated using an extracranial-intracranial (EC-IC) bypass. The use of the internal maxillary artery (IMA) in the subcranial-intracranial (SC-IC) bypass was recently described as an alternative treatment. However, the haemodynamics of this new approach have not been defined. METHODS: The haemodynamic parameters (flow volume [FV], internal diameter [ID], time-averaged mean velocity [TAM], pulsatility index [PI] and resistance index [RI]) of the IMA-radial artery graft (RAG)-middle cerebral artery (MCA) (n = 12) bypass and superficial temporal artery (STA)-MCA bypass (n = 18) were measured using intraoperative duplex ultrasonography and compared. RESULTS: The FV was 81.36 ± 30.41 (62.05-100.70) ml/min for the IMA-RAG-MCA bypass. This was significantly higher than that of the STA-MCA bypass (27.25 ± 9.32 (22.62-31.88) ml/min; P < .01). The ID and TAM in the IMA-RAG-MCA bypass were higher than in the STA-MCA bypass (P < .01; P < .01). No significant differences were observed in PI (P ≈ .21) and RI (P ≈ .08). The early patency rate (one month after the operation) was 100% for the IMA-RAG-MCA bypass and 94% for the STA-MCA bypass. CONCLUSIONS: The IMA-RAG-MCA bypass provides moderate to high blood flow to the revascularized territory and blood flow was higher by this method than the STA-MCA bypass.

Outcome of Radical Surgical Resection for Craniopharyngioma with Hypothalamic Preservation: A Single-Center Retrospective Study of 1054 Patients.

OBJECTIVE: A retrospective review of the surgical outcome for patients with craniopharyngioma (CP) treated in a single neurosurgical center with surgical resection using visualization to ensure hypothalamic preservation. METHODS: The study included 1054 patients. Before 2003, a pterional cranial approach was preferred for 78% of patients; after 2004, the unifrontal basal interhemispheric approach was performed in 79.1% of patients. RESULTS: Complete tumor resection was achieved in 89.6% of patients; vision improved in 47.1% of patients who had preoperative vision impairment. However, diabetes insipidus worsened in 70.4% of patients and new-onset diabetes insipidus occurred in 29.7% of the remaining patients. Pituitary stalk preservation occurred in 48.9% of cases. There were 89.6% of patients with total tumor removal; 13.3% of patients showed tumor recurrence within an average of 2.8 years. Of 69 follow-up patients with a subtotal or partial resection, 94.2% showed tumor recurrence within an average of 4.3 months. Of the total patients, 82.3% fully recovered. CONCLUSIONS: This study has shown that radical surgical resection of CP using microsurgical excision can be effective with a good patient outcome without more limitations on each individual tumor of distinct features despite the impact of recent endoscopic techniques on CP surgery. The surgical approach depends on a direct and wider visualization of CP located in the midline with preserving hypothalamic structures by identifying some hypothalamic landmark structures. After surgery, most patients can resume their normal activities even after aggressive tumor removal, although patients require postoperative hormonal replacement.

Internal maxillary artery to intracranial artery bypass: a case series of 31 patients with chronic internal carotid/middle cerebral arterial-sclerotic steno-occlusive disease.

OBJECTIVE: To evaluate the effectiveness of internal maxillary artery (IMA) - radial artery graft (RAG) - middle cerebral artery (MCA) bypass surgery for chronic arterial-sclerotic severe stenosis or occlusion of the internal carotid artery (ICA) or MCA. METHODS: A retrospective study was conducted in 31 patients with ischemic cerebrovascular disease who underwent bypass surgery of the IMA with a RAG of the MCA. Twenty-seven patients had complete occlusion of the ICA or MCA, and four patients had severe stenosis of the M1 segment of the MCA. RESULTS: Patent IMA-RAG-MCA in 30 (96.8%) patients was confirmed by angiography after surgery. One case developed a new motor aphasia due to unsuccessful bypass. Eleven transient ischemic attacks (TIA) and five ischemic strokes resolved following surgery. The other 14 cases showed some improvement without ischemic events at one month following surgery. Prior to surgery, mean ± SD National Institute of Health Stroke Scale (NIHSS) score was 5.4 ± 1.1 in the ischemic stroke group. In the first month post-procedure, the NIHSS score decreased significantly to 3.8 ± 1.2, (p < 0.01). Perfusion weighted imaging (PWI) or computed tomography perfusion (CTP) indicated improved hemodynamics in 30 patients. In addition, seven patients demonstrated improved glucose metabolism on 18-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) postoperatively. No new neurological deficit occurred in the 30 patients during a 2.19 ± 1.59 years of follow-up. CONCLUSIONS: By supplying an adequate flow to a larger flow territory of chronically stenotic/occlusive major cerebral arteries, IMA bypass surgery is efficient for restoring hemodynamics in selected patients and improving their neurological deficits.