This microsurgical study attempts to analyze the intraoperative anatomic vascular variations associated with the anterior communicating artery (ACoA) aneurysms in 120 patients who were operated on at the Neurosurgical Department of Atatürk University Medical School, Erzurum, Türkiye. All patients underwent radical surgery for aneurysm by the right pterional approach. The findings were recorded during surgical intervention and through the slides and videotapes of the operations. A total of 72 (60%) of our patients had vascular variations in the vicinity of the ACoA. Marked hypoplasia of the A1 segment of anterior cerebral artery (ACA) at the right or left side (26.6%, n = 32), median artery of the corpus callosum (MACC) (14%, n = 17), duplication of the ACoA (8.3%, n = 10), duplication of the A1 segment of ACA (7.5%, n = 9) and azygous pericallosal artery (3.3%, n = 4) were the variations that were observed during operations. A retrospective study of the cerebral angiograms of the cases indicated that preoperative diagnosis of the A1 or ACoA duplication was not possible, 14 (82.4%) of the 17 MACC's were easily identified, while three (17.6%) could not be diagnosed. From this intraoperative study, we concluded that, regardless of whether a vascular variation has been identified preoperatively, ACoA aneurysm surgery should be undertaken with the possibility of an MACC in mind. The recognition of the anatomic variations of the ACoA and the detailed knowledge of the microvascular relationships of the aneurysms will allow the neurosurgeons to construct a better and safer microdissection plan to save time on the one hand and to prevent postoperative neurological deficits on the other.

The pterional approach is commonly employed in surgery of the anterior circulation and upper basilar artery aneurysms, as well as for the tumors of orbital, retroorbital, sellar, chiasmatic, subfrontal and prepontine areas and lesions around the sella especially for lesions behind the clivus. Also tumors arising from the medial sphenoid ridge, the superior orbital fissure, the anteromedial temporal surface, or the cavernous sinus region are approached through a pterional exposure. The surgical technique is based on the experience, training and observation of the neurosurgeon. One technique is not necessarily better than another. Regardless of the surgical technique, the end results depend on a rigorous, methodical, systematic, and step-by-step approach to the target, securing it with minimal injury to surrounding structures. In this study, we have analyzed the intraoperative anatomical findings of the Sylvian vein and fissure, lenticulostriatal artery, olfactory nerve, and recurrent artery of Heubner and showed the surgical pitfalls in 700 patients with different diagnoses that were operated on with the pterional approach. The findings were recorded during surgical interventions and through the slides and videotapes of the operations. Also, we have stressed the preservation of the frontotemporal branch of the facial nerve, the delicate retraction of frontal lobe, the cottonoid retraction in temporal lobe and the preservation of olfactory nerve functions.

Damage to the olfactory nerve during the pterional approach to the anterior communicating artery aneurysms has not previously been investigated in a quantified manner. In this retrospective study, 100 patients with anterior communicating artery aneurysms, for whom the pterional approach was employed, were observed from the point of view of postoperative olfactory nerve function. In the postoperative period only three cases suffered from the impaired sense of smell ipsilateral to the side of surgery. 15 patients objectively showed olfactory nerve distinctions. The functions of olfactory nerve could be preserved at a relatively high rate of 85 per cent. This high rate resulted from the microtechnique employed as well as the relatively cautious frontal lobe retraction which was less than 1.5 cm.

The intramedullary spinal tuberculoma, although a rare entity, must be considered in the differential diagnosis of the spinal cord compression in patients with a history of tuberculosis, human immunodeficiency virus, and those who have a bad socioeconomic condition and bad nutrition habit. When confronted with a progressing neurologic deficit, a combination of microsurgical resection and antituberculous chemotherapy with the avoidance of steroids should be the choice of treatment for intramedullary tuberculomas.