Giant anterior communicating artery aneurysm
Giant aneurysm of the anterior communicating artery are rare.
Treatment
Case reports
An unusual case of bitemporal hemianopsia caused by a large intracranial aneurysm of the ACoA. A 41-year-old woman was admitted to our neurosurgical department with a sudden-onset bursting headache and visual impairment. On admission, her vision was decreased to finger counting at 30 cm in the left eye and 50 cm in the right eye, and severe bitemporal hemianopsia was demonstrated on visual field testing. A brain computed tomography scan revealed a subarachnoid hemorrhage at the basal cistern. Conventional cerebral catheter angiography of the left internal carotid artery demonstrated an 18×8 mm dumbbell-shaped aneurysm at the ACoA. Microscopic aneurysmal clipping was performed. An ACoA aneurysm can produce visual field defects by compressing the optic chiasm or nerves. We emphasize that it is important to diagnose an aneurysm through cerebrovascular study to prevent confusing it with pituitary apoplexy 1).
A patient presented with visual dysfunction, gait ataxia and urinary incontinence. MRI showed a giant suprasellar mass. At surgery, the lesion was identified as being an aneurysm arising from the anterior communicating artery. The difficulty in preoperative diagnosis and relevant literature are reviewed 2).
Patel NJ, Filippidis A. IMAGES IN CLINICAL MEDICINE. A Giant Aneurysm of the Anterior Communicating Artery. N Engl J Med. 2015 Aug 6;373(6):560. doi: 10.1056/NEJMicm1413193. PMID: 26244309.
A 70-year-old female patient, in whom a single seizure was the only symptom of a giant AcomA aneurysm, with no neurological deficit. The diagnosis of unruptured giant AComA aneurysm was made with cranial CT, MRI and angiography. The patient refused surgical intervention, was treated with anti-epileptic therapy and has been asymptomatic for 7 months. We suggest that elderly patients presenting with a first seizure need detailed evaluation and giant aneurysms, which may be confused with other intracranial space-occupying lesions, need to be considered in the differential diagnosis 3).
A case of giant aneurysm arising from the anterior communicating artery, 24 X 28 X 30 mm in diameter was found in a 30 year old man. About ten years ago he became blind and recently developed right anosmia and diencephalic seizures. No subarachnoid hemorrhage, however, was found. Radiograms and tomograms of the cranium showed a ring-like calcification, but by angiography it couldn't be recognized as a giant aneurysm. The right frontal craniotomy and partial resection, therefore, was performed. A histological study of the resected material revealed that it was a spontaneously thrombosed giant aneurysm. The inner layer of its wall had neither endothelium nor elastic lamina, but had deposits of calcium salt. The outer layer was composed of collagen fibers without cell infiltration. The aneurysm was thrombosed except for its neck but its organization occurred incompletely. We want to emphasize the importance of a correct preoperative diagnosis, as an erroneous operative procedure can result in disaster. Volume, viscosity and tension of flowing blood into the aneurysm as well as the size of its neck and dome regulate dynamic properties. These properties may determine the enlargement rate or growth of the aneurysm. The dynamic characteristics and features of the inner surface of the aneurysmal wall may regulate the formation of thrombosis in the aneurysm. The intraluminal thrombosis and strength of aneurysmal wall, for example, calcium deposits, may prohibit aneurysm from its rupture 4).