[Radiation-induced meningiomas: analysis of 33 cases]. / Radioindutsirovannye meningiomy: analiz 33 nablyudenii.

BACKGROUND: Development of meningiomas correlating with irradiation has been described in the last century. Different biological features of radiation-induced meningiomas depending on dose and type of irradiation have been observed in recent years. MATERIAL AND METHODS: There were 8848 patients (women - 74.3%) with intracranial meningiomas for the period from 2000 to 2014 who underwent surgery at the Burdenko Neurosurgical Center. Radiation-induced meningiomas were identified in 33 patients (13 (38%) men and 20 (62%) women) aged 16-76 years (median 56 years). Medical data were retrospectively analyzed. Follow-up period ranged from 5 to 22 years (median 12) after verification of histological diagnosis. Meningiomas were preceded by X-ray irradiation of the scalp for ringworm (microsporia or trichophytosis) in 26 cases (79%) (group A). Group B enrolled 7 (21%) patients after previous radiotherapy for other tumors (retinoblastoma, chiasmal glioma, pituitary adenoma, basalioma). Data were compared using Mann-Whitney and Fisher's exact tests. RESULTS AND DISCUSSION: Incidence of radiation-induced meningiomas was 0.37% in our sample. Meningioma diagnosis dates after X-ray epilation (median 52 years) significantly differed from that after radiotherapy (median 22 years) (Mann-Whitney test, p=0.0003). Primary multiple meningiomas were diagnosed only in the 1st group (Fisher's exact test, p=0.0005). Recurrent meningiomas after the first surgery were more common in the first group (58%) compared to the second one (14%) (Mann-Whitney test, p=0.0003). CONCLUSIONS: The latency period is shorter after radiotherapy (median 22 years compared to 52 years after X-ray epilation). Incidence of atypical and malignant meningiomas directly correlates with irradiation dose. Approximately equal incidence of radiation-induced meningiomas after X-ray epilation in women and men can indicate other mechanisms of development of these tumors in comparison with spontaneous ones. Radiotherapy is followed by occurrence of meningiomas within the irradiated area. These tumors are usually single. In case of X-ray epilation, the tumors may be localized anywhere within the intracranial space (convexital and/or parasagittal localization in 77% of cases). Multiple neoplasms occur in 42% of cases. Refusal of head X-ray epilation for the treatment of a ringworm for the last 50 years may be followed by reduced incidence of radiation-induced meningiomas, especially multiple ones. However, extended indications for radiotherapy of various brain diseases can result an increase of the incidence of meningiomas within the irradiated area.

[Comprehensive treatment of patients with parasagittal meningiomas]. / Kompleksnoe lechenie bol'nykh s parasagittal'nymi meningiomami.

For many years, radical surgery was considered the only effective method for treating meningiomas, including parasagittal meningiomas (PSM). However, accumulated experience makes it evident that extensive resections in the parasagittal region lead to impaired venous outflow and involve high rates of disability and mortality. In recent decades, stereotactic radiotherapy has been developed and widely implemented in practical neurosurgery, its role in the treatment of PSM patients is discussed in this work. MATERIAL AND METHODS: A sample of publications in the PubMed search system was taken using the following keywords: meningioma, parasagittal, superior sagittal sinus, stereotactic radiosurgery, stereotactic radiation therapy. No publications of evidence levels 1 and 2 have been found. Out of 123 works, 32 most relevant were selected. RESULTS AND DISCUSSION: Currently, both neurosurgeons and radiologists are involved in the treatment of PSM. An analytical review of the literature on the treatment of PSM is presented. Both surgical treatment and radiation therapy have their pros and cons. No general approach to the treatment of these tumours has been developed to date. A comprehensive treatment is considered to be effective - the maximum possible removal of the tumor without damaging functionally significant structures, including venous outflow pathways, followed by radiotherapy for tumor residues. CONCLUSION: In the existing literature, it was not possible to identify a single decision-making algorithm for the tactics of multimodality therapy for PSM patients, including the one for manipulations on the superior sagittal sinus and with regard to the role of ir irradiation radiation methods.

[The orbitozygomatic approach. History, technique, and modifications]. / Orbitozigomaticheskii dostup. Istoriia, tekhnika, modifikatsii.

The orbitozygomatic approach (OZA) has been used in neurosurgical practice since the 1980s. Many approach modifications have been proposed; anatomical and clinical developments have been conducted in many clinics. However, there is no algorithm for choosing an approach option, depending on the type and topographo-anatomical features of pathology. MATERIAL AND METHODS: We searched for publications in the PubMed and Medscape databases using the keywords 'orbitozygomatic'. RESULTS: A total of 447 publications matching the search terms were found. In most of them, the approach was either not actually orbitozygomatic or was mentioned in the description of a clinical case. One hundred and nineteen full text Russian or English papers were available for detailed analysis. Of these, we selected 72 most relevant publications. DISCUSSION: There were no studies demonstrating disadvantages of the OZA compared to traditional craniotomies. Orbitozygomatic approaches are widely used in routine neurosurgical practice. Existing approaches are not without disadvantages. The publications are based on small material. The recommendations on choosing the optimal OZA option are based on the authors' opinion, i.e. they satisfy the minimum level of evidence. There are no studies comparing the efficacy of OZA options in different types and topographo-anatomical variants of neurosurgical pathology of the anterior and middle skull base. CONCLUSION: The reasonability of using the orbitozygomatic approach in neurosurgical practice is obvious. There are a large number of orbitozygomatic approaches and their modifications. The modern literature lacks an algorithm for choosing the optimal OZA option for specific types and topographo-anatomical variants of the pathological process.