Three dimensional digital subtraction angiography imaging of a ruptured aneurysm on the anterior communicating artery

Intraoperative Matas test using microscope-integrated intraoperative indocyanine green videoangiography with temporary unilateral occlusion of the A1 segment of the anterior cerebral artery

OBJECTIVE

The aim of the present study was to assess a new technique of surgical microscope-based indocyanine green (ICG) videoangiography (VAG) to confirm the patency of the anterior communicating artery (AcomA) after clipping AcomA aneurysms.

METHODS

Aneurysmal clipping of five cases of unruptured, broad-neck AcomA aneurysm was performed using the Carl Zeiss Surgical Microscope OPMI Pentero INFRARED 800.

RESULTS

In all five patients, after clipping AcomA aneurysms, the patency of AcomA was confirmed using ICGVAG findings and temporary unilateral occlusion of the A1 segment of the anterior cerebral artery using temporary clips. Images were excellent and enabled a real-time surgical assessment because the structures of interest, including vessels, perforating arteries, or residual aneurysm neck, were visible to the surgeon's eye under the microscope in all five patients.

CONCLUSIONS

ICGVAG and temporary unilateral occlusion with clips provides a simple, reliable, real-time, and rapid intraoperative assessment of the patency of AcomA. This technique may help to improve the quality of neurosurgical procedures.

L’angio-scanner cérébral multibarrette peut-il supplanter l’angiographie conventionnelle dans le diagnostic étiologique des hémorragies sous-arachnoïdiennes ?

AIM OF THE STUDY

To evaluate the reliability of CT angiography in the diagnosis of non traumatic subarachnoid hemorrhage.

MATERIALS AND METHODS

We prospectively studied 57 patients presenting with non traumatic subarachnoid hemorrhage. In all cases, CT angiography of the circle of Willis was performed, followed by conventional angiography. We compared the results of both techniques, with conventional angiography considered as the gold standard.

RESULTS

The specificity of CT angiography for diagnosing intracranial aneurysms was 100% with sensitivity and negative predictive values of 86% and 65% respectively. The aneurysms that were not diagnosed on CT angiography were located on the supra-cavernous internal carotid artery and their size was less than 5mm. Futhermore CT angiography failed to diagnose the other causes of subarachnoid hemorrhage.

CONCLUSION

CT angiography can be considered as a first line imaging technique for diagnosis of non traumatic subarachnoid hemorrhage. However, conventional angiography including three dimensional acquisitions must be performed for all cases where the cause of hemorrhage remains undiagnosed at CT angiography.

Multiple aneurysms of the anterior communicating artery: radiological and surgical difficulties

OBJECT

Multiple aneurysms of the anterior communicating artery (ACoA) occur rarely and have not been well investigated previously. The authors report on a consecutive series of six patients who each harbored multiple ACoA aneurysms. The radiological and surgical difficulties encountered in treating these complex and uncommon aneurysms are described and the pertinent literature is reviewed.

METHODS

Between October 1996 and August 2003, the authors surgically treated 146 patients with ACoA aneurysms. Six (4.1%) of these patients harbored multiple aneurysms of the ACoA. Four of these patients were men and two were women; their ages ranged from 36 to 72 years. Five patients had two aneurysms and one patient had three. All underwent surgery performed using the pterional approach. The clinical presentations, angiograms, intraoperative difficulties, and surgical results were retrospectively analyzed. All patients had premorbid hypertension. In two cases, the aneurysms were initially misdiagnosed as a single complex aneurysm based on routine cerebral angiograms, but special angiographic views demonstrated double aneurysms. In one case, multiple ACoA aneurysms could be identified using three-dimensional (3D) computerized tomography (CT) angiography. The size of the ACoA aneurysms ranged from 3 to 12 mm (mean 5.3 mm). A total of 13 ACoA aneurysms were successfully occluded in the six patients. Four patients were discharged in good condition, and two patients died.

CONCLUSIONS

Although multiple ACoA aneurysms are quite rare, the following points should be kept in mind. (1) In bilobular ACoA aneurysms, special angiographic projections and 3D CT angiography or 3D digital subtraction angiography should also be performed to obtain a correct diagnosis. The differentiation of two aneurysms from a bilobular aneurysm during the preoperative period is important for surgical planning. (2) Angiographically, detection of the ruptured aneurysm is often difficult. (3) Resection of the gyrus rectus is necessary to obtain a good operative exposure. 4) Clip selection and sequencing are important. Straight clips with short blades should be preferred to avoid narrowing of the surgeon's view and a collision between the clips.