Vision is a complex sense that is widely represented in the cortex and involves multiple pathways that can be affected by conditions amenable to surgical treatment. From a neurosurgical point of view, the treatment of major lesions affecting the optic nerve, such as tumours, intracranial hypertension, trauma and aneurysms, can be approached depending on the segment to be worked on and the surrounding structures to be manipulated. Therefore, surgical manipulation of the visual pathway requires a detailed knowledge of functional neuroanatomy. The aim of this review is to present the functional and microsurgical anatomy of the second cranial nerve, through illustrations and cadaveric dissections, to support the choice of the best surgical approach and avoid iatrogenic injuries. For this purpose, a literature search was performed using the PubMed database. Additionally, cadaveric dissections were performed on adult cadaver heads fixed with formaldehyde and injected with coloured silicone.

Nowadays, the middle cranial fossa approach (MFA) is one of the most useful operative procedures in skull base surgery. When performed properly, it provides a relevant adjunct to treating complex skull base lesions. MFA allows one to resect the anterior petrous bone (anterior petrosectomy), open the internal auditory canal (IAC), and access the lateral wall of the cavernous sinus and the infratemporal fossa. Knowledge of the anatomical structures of the middle cranial fossa and cavernous sinus is mandatory to perform this approach. We report in detail the standard extradural subtemporal route for the anterior petrosectomy and MFA. The main indications for this approach are intradural lesions localized medially to the trigeminal nerve, subtemporal interdural and extradural tumours and neoplasms involving the IAC (including IAC pathology). Moreover, we describe the extended middle fossa approach, consisting in the anterior extension of MFA, indicated for intradural tumours of the superior cerebello-pontine angle and of prepontine clivus (retroclival lesions, ventral brainstem tumours, and cavernomas), for infratemporal fossa lesions, and cavernous sinus pathologies. Even if the anatomical landmarks of the middle cranial fossa and lateral skull base are well known, training with cadaver dissection is necessary for any skull-base surgeon to perform an optimum MFA. The cadaver-lab dissections simplify the learning of anatomical structures, and prepare the surgeon properly for this technically challenging approach.

Recurrences of benign peripheral nerves sheaths tumours (BPNST) after total resection were described in 2.6–11.0% of patients. The significance of the histological features of recurrent BPNST is still insufficiently studied.
Aim. To compare the pathomorphological features of recurrent and non-recurrent BPNST (schwannomas and neurofibromas).
Materials and methods. A retrospective assessment was made of 101 patients with BPNST with a degree of anaplasia corresponding not more than Grade I. Recurrence of BPNST developed in 13 (12.9%) cases. The study included patients with histological archive: the study group (n = 7) included patients with one or more relapses of BPNST, the control group included patients (n = 5) without relapses after surgery for 5 or more years. The main clinical characteristics were studied and histological examination was performed.
Results. There were no differences between the groups in baseline characteristics (the type of tumour (schwannoma, neurofibroma), distribution by sex, age, localization, clinical symptoms). The relapse rate among patients with neurofibromas was 8 in 3 patients vs. 6 in 5 patients with schwannomas. In all cases of recurrent schwannomas and in one of neurofibroma, the histological pattern was predominantly monophasic with rhythmic structures like Verocay bodies with underlined pattern and nuclear hyperchromasia, in contrast to the control group, represented by tumours with a mixed type of structure with uniform alternation of various histological patterns (p < 0,05). Endothelial proliferation and lymphocytic infiltration in the stroma and perivascular area were more common in the relapse group (p < 0.05). Pathomorphological signs of anaplasia: cell-nuclear polymorphism, nuclear hyperchromasia, endothelial proliferation, mitosis, as well as minor signs of anaplasia: solidization, muirization of the fascicular pattern of a tumour and apoptotic bodies were found with the same frequency in both groups. With relapse, the capsule was lost, thinned, intermittent, and sometimes invaded the surrounding tissues.
Conclusion. Tumours with the initial signs of anaplasia, such as endothelial proliferation, tendency to hypercellularity, and histological pattern with prominent Verocay bodies dominate among recurrent BPNST.

Aim. To study markers of blood-brain barrier dysfunction (BBB) in patients with pharmacoresistant epilepsy (PhRE) – the amount of VEGF in endotheliocytes of brain capillaries, TNF-α in brain tissue and cytokine profile in blood serum.
Materials and methods. The study included 30 patients with PhRE who underwent anterior temporal bloc resection. Histological samples of the brain were examined to assess the amount of VEGF and TNF-α; the concentration of cytokines in the blood serum was determined.
Results. In the PhRE group, the densitometric density of cells expressing VEGF and the amount of TNF-α in the epileptogenic focus were higher than in the control groups (p < 0.001; p < 0.05). Compared with the control, the serum concentrations of IL-2 (0.98 ± 0.28 pg/ml vs. 2.80 ± 0.71 pg/ml; p < 0.001), IL-8 (14.04 ± 1.46 pg/ml vs. 26.13 ± 3.80 pg/ml; p < 0.001) and EGF (43.72 ± 5.63 pg/ml vs. 83.62 ± 24.06 pg/ml; p < 0.05) were statistically significantly lower in the PhRE group, and the amount of TNF-α (33.09 ± 1.23 pg/ml vs. 24.85 ± 1.32 pg/ml, p < 0.05), IL-4 (43.73 ± 2.57 pg/ml vs. 32.37 ± 5.80 pg/ml, p < 0.05), IL-5 (43.73 ± 2.57 pg/ml vs. 32.37 ± 5.80 pg/ml; p < 0.05), IL-7 (16.65 ± 3.07 pg/ml vs. 8.13 ± 1.67 pg/ml; p < 0.05), GRO (growth-regulated protein) (3054.0 ± 200.8 pg/ml vs. 1367.0 ± 187.3 pg/ml; p < 0.001), VEGF (316.10 ± 55.28 pg/ml vs. 95.22 ± 15.78 pg/ml; p < 0.01) are statistically significantly higher. There were no significant differences in the concentration of IL-1β, IL-1RA, IL-10 and IFN-γ between the PhRE group and the control.
Conclusion. Based on the studied cytokine profile, there is no systemic inflammation in patients with PhRE. The established overexpression of VEGF in the brain and an increase in its concentration in the blood, combined with a decrease in serum EGF concentrations and an increase in GRO, as well as pro-inflammatory factors, indicates damage to the BBB. A high amount of TNF-α in the epileptic focus indicates neuroinflammation, and an increased concentration of this marker can be found in the blood of patients with BBB dysfunction.

Background. In modern neurosurgery, preference is given to less invasive procedures. A classic example is switching from standard surgical approaches to keyhole approaches, in particular transition from pterional to minipterional approach. In turn, addition of extradural resection of the anterior clinoid process to the minipterional approach significantly expands the range of its indications.
Method. The paper analyses the stages and main features of microsurgical clipping of carotid-ophthalmic aneurysms through the minipterional approach with extradural anterior clinoidectomy in patients operated in the Federal Centre of Neurosurgery (Tyumen, Russia) by professor Sufianov.
Conclusion. The technique described in this research is a safe surgical approach, which demonstrates the efficacy of adding some skull base surgery elements to keyhole approaches. This type of craniotomy could become a method of choice for many neurosurgical conditions.

Aneurysms of the internal carotid artery are the second most common among cerebral aneurysms. When an aneurysm is located in the ophthalmic segment of the internal carotid artery (ICA), the intravascular treatment method is a priority. At the same time, the treatment of recurrent and non-radially switched-off aneurysms of this localization remains a subject of discussion.
Case report. We present a 42-year-old patient with a ruptured ICA aneurysm who was admitted in a serious condition. Initially, the patient underwent partial occlusion of the aneurysm cavity with endovascular coiling. In the control cerebral angiography 3 months after the haemorrhage, the recanalization of the aneurysm was verified, which served as an indication for repeated surgical intervention. We preferred the microsurgical method of treatment. A control angiographic study 1 year after the second operation confirmed the radical shutdown of the aneurysm.
Discussion. The presented case illustrates the need for a flexible approach in the treatment of complex paraclinoid aneurysms. The choice of endovascular treatment of such aneurysms in the acute period of haemorrhage is justified as the most sparing, although less radical. Depending on the nature of the embolization performed, the timing of the control angiographic examination should be selected individually and can be reduced to 2 months. If there are indications for repeated surgical intervention, it should be performed by the safest method, providing total shutdown of the aneurysm and reducing the volumetric impact of the aneurysm dome on the optic nerve.