51 research outputs found
Endoscopic, transnasal approach to the orbital tumors using image-guided neuronavigation system
Histopathological diagnosis of the intraorbital tumors is of crucial value for planning further conservative or surgical treatment. Small intraorbital lesions located posteriorly to the bulb, intraconally or in the orbital apex are extremely difficult to reach via traditional external approach. Precise fine needle aspiration in these cases is not easy and a small amount of examined material may lead to misdiagnosis. The aim of the study was to evaluate the usefulness of nasal endoscopy and image guided neuronavigation system in the diagnosis of orbital tumors. Seven patients with intraorbital tumors were diagnosed. All the lesions were precisely localized and the biopsy was succesfully taken using transnasal endoscopy supported by neuronavigation system. None of the patients developped ocular symptoms aggravation after the procedure. Neuronavigation system facilitated precise localization of the lesion, helped to protect vulnerable orbital structures and decreased the risk of complications
Endoscopic surgical interventions inside the orbit
Despite of the well known advances of the endoscopic techniques, only recently single reports have been published pointing at the orbit as a target for endoscopic surgical intervention using both transnasal or external approach. In this contribution we would like to present the results endoscopic surgery in 32 patients with various intraorbital pathologies. All patients were operated by a co-working team of ENT surgeon and neurosurgeon using image guidance neuronavigation system and intraoperative ultrasonography for precise anatomical orientation. Transnasal endoscopic transethmoidal or transmaxillar approach were chosen for biopsy of intraorbital mass lesions, removal of medially located intraorbital tumors and foreign bodies, drainage of intraorbital (including intraconal)hematomas and abscesses, repair of blow out fractures. External endoscopic precaruncular, lateral retrocanthal, inferior preseptal and transconjunctival approaches were used for resection of orbital tumors and optic nerve decompression in the region of orbital apex.In all cases the goal of the operation was achieved i.e. biopsies were taken from the central, representative part of the pathological mass, tumors and foreign bodies were removed, orbits were decompressed by successful drainage and fractured walls of the orbit were reconstructed. In few patients transient aggravation of ocular symptoms like diplopia or ptosis was observed in immediate postoperative period but they resolved completely within the first 2-3 months after the surgery.In spite of anatomical limitations the orbit can be explored with endoscopy but the operative technique is rather demanding and satisfactory results are to be obtained only with extensive surgical experience supported with high quality equipment.Supported by: This work was supported by grant No 13-0037-10 from the National Center of Research and Development (NCBiR
N-cadherin, beta-catenin and connexin 43 expression in astrocytic tumours of various grades
Introduction: Astrocytic tumors are the most
common primary brain tumors, but little is known about
their etiology and prognostic factors. N-cadherin and
beta-catenin are adhesive proteins, and are often
overexpressed in many types of cancers, including breast
or colorectal cancer, resulting in better prognosis.
Connexin 43 is a gap junction protein involved in cellcell signaling pathway taking part in the process of
carcinogenesis. The aim of the study was to evaluate Ncadherin, beta-catenin and connexin 43 expression in
astrocytic tumors of various grades.
Materials and methods: We examined 131 cases of
astrocytic tumors, including 26 cases of diffuse
astrocytoma (group I), 44 anaplasic astrocytomas (group
II) and 61 glioblastoma cases (group III) - primary and
secondary. To evaluate N-cadherin, beta-catenin and
connexin 43 expression, we used immunohistochemical
reaction with specific antibodies (Santa Cruz
Biotechnology). The obtained results were correlated
with clinical and morphological features.
Results: Beta-catenin expression was observed in
69.3% of diffuse astrocytomas, 75% of anaplastic
astrocytomas, and 82% of glioblastoma cases. Ncadherin expression was observed in 92.3% of diffuse
astrocytomas, 90.1% of anaplastic astrocytomas, and in
all glioblastoma cases. Connexin 43 was observed in
76.9% of diffuse astrocytomas, and in all cases of
anaplastic astrocytomas and glioblastomas. Beta-catenin
expression was significant within the nucleus of
neoplastic cells in groups I and II. In group III, staining
was observed only in the cellular membranes. Ncadherin and connexin 43 expression was observed only
in the cells’ membranes. In glioblastomas, both primary
and secondary, all protein expression was significant
within the cells surrounding the necroses and blood
vessels and weak or absent in the tumor’s margins.
Conclusion: Our study shows that beta-catenin
nuclear expression in group of diffuse astrocytomas and
anaplastic astrocytomas is evidence for transcriptional
function of beta-catenin in those groups. Strong Ncadherin and connexin 43 expression in those groups
may be evidence for their role in tumor formation and
progression. However, in glioblastomas a very important
role of all examined proteins is generating intracellular
connections to facilitate the escape of tumor cells from
the effects of hypoxia or their accumulation around the
blood vessels rather than tumor invasion into the brain
parenchyma
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