Sphenoorbital meningiomas (SOM) are a subgroup of skull base tumors with soft tissue component in the orbit and anterior and/or middle cranial fossa. According to different authors, SOMs account for ...2-12% of all intracranial meningiomas. Reconstruction of bone defects after resection of SOM has own nuances. Along with cranial vault repair, patients encounter with cosmetic defects following facial skull lesion, ophthalmic symptoms due to orbital defects, dental and functional problems associated with opening of the mouth in case of damage to maxilla and mandible. Predominant infiltrative growth of tumor and common large bone defects involving various anatomical regions require multiple implants or implants with complex shape. Moreover, contact of implantation area with nasal cavity and paranasal sinuses requires additional impermeability of soft tissue reconstruction and inertness of materials.
To summarize available modern data on bone defect closure after resection of SOM.
The authors reviewed available data on bone defect closure after resection of SOM. Effectiveness of modern methods of reconstruction and safety of materials were assessed.
We analyzed 96 available references. Technical features of tumor resection, materials used for bone defect closure and modern possibilities of 3D technologies in reconstructive surgery were described. The authors proposed the algorithms for selecting the materials for bone defect closure after resection of SOM.
Improvement of surgical technique and development of new materials and technologies significantly improve cosmetic and functional results. A large percentage of negative ophthalmologic outcomes and high risk of complications in SOM surgery require further studies and elaboration of modern techniques.
Individual polymer implants are widespread for bone reconstruction after decompressive craniectomy. Despite the availability of customized titanium products, various specialists and hospitals prefer ...polymer implants.
To compare the methods of modeling and manufacturing the polymethylmethacrylate implants and identify the features affecting the quality of reconstruction.
We analyzed 14 patients with extensive skull defects after installation of polymethyl methacrylate implants. Software used for modeling of individual implants by different specialists was compared.
Satisfactory reconstruction result was obtained in all cases. There were no infectious complications. The authors outlined certain important aspects for modeling of individual polymer products: local use of anatomical thickness of the implant, leaving safe spaces, prevention of temporal retraction, template-based resection before reconstruction.
To date, skull defect closure with polymeric materials remains relevant, and even has certain advantages over customized titanium products.
To develop a classification of the completeness of brain aneurysm exclusion according to CT angiography for determining further diagnostic and curative strategy.
The study included 138 patients who ...had 164 brain aneurysms. Clipping was carried out at the Burdenko Neurosurgery Center in 2013-2017. Titanium clips were used in 111 cases, cobalt clips - in 53 patients.
Completeness of brain aneurysm exclusion was assessed in 149 cases using CT angiography. In 15 cases, artifacts from cobalt clips impaired assessment. Total exclusion was achieved in 136 (91.3%) cases, subtotal (a remainder of residual neck) - in 10 (6.7%) cases, complete exclusion of the body and bottom (patent neck) - 2 (1.3%) patients, partial exclusion (partially patent bottom) - 1 patient (0.7%). In this series, a clip prevented complete contrast enhancement of brain aneurysm bottom in all cases.
CTA is a reliable method for assessing the quality of exclusion of brain aneurysm in patients with implanted titanium clips. In case of cobalt clips, stratification depending on severity of CT artifacts should be performed for data interpretation. In some cases, artifacts impair visualization of the vessels adjacent to the clips. In these patients, direct cerebral angiography or dual-energy computed tomography scanners with metal artifact suppression programs should be recommended.
Follow-up is recommended for patients with remnants of residual cervix. Redo surgery is indicated for completely patent neck, as well as partial or complete contrast enhancement of aneurysm bottom.
To evaluate mechanical strength of three methods of polymethyl methacrylate skull implant fixation in two experimental models.
The first experiment was performed on a plastic model that was as close ...as possible to bone in structural characteristics. The second experiment was performed on a biological specimen (a ram's head). We assessed the quality of implant fixation to bone window edges by craniofixes, ties and microscrews and lateral intercortical screws.
Craniofixes are feasible for small flat flaps, but not advisable for wide highly curved implants. They are also the most expensive method of fixation. Implant fixation by ties and microscrews is a universal method comparable in price to craniofix. Lateral intercortical fixation is effective both for small flat implants and wide implants with large curvature. However, this method is not always applicable.
Combined fixation by lateral intercortical screws and ties allows for the most effective fixation while reducing the overall price of consumables.
Dural defect closure after resection of cranioorbital meningiomas has its own specifics. Extended malignant lesions and common large bone defects involving various anatomical regions require multiple ...implants or implants with complex geometry. The features of this stage of reconstruction were described in the previous issue of the Burdenko Journal of Neurosurgery. At the same time, contact of implant with nasal cavity and paranasal sinuses dictates additional requirements for tightness of soft tissue reconstruction and inertness of material. In this review, we describe modern and historically interesting methods of reconstruction of soft tissue defects following resection of cranioorbital meningioma.
To summarize and analyze available literature data on reconstruction of soft tissue defects following resection of cranioorbital meningioma.
The authors reviewed available data on reconstruction of soft tissue defects after resection of cranioorbital meningiomas. Effectiveness of reconstruction techniques and safety of materials were analyzed.
The authors analyzed 42 available full-text articles. Features of growth and natural course of cranioorbital meningioma, methods of soft tissue defects closure, modern materials and sealing compositions are described. Considering these data, the authors proposed the algorithms for selecting materials for dural reconstruction after resection of cranioorbital meningioma.
Improvement of surgical technique, development of new materials and technologies increase the efficiency and safety of dural defect closure. Nevertheless, high incidence of complications associated with dura mater repair necessitates further research in this area.
Giant cerebral aneurysms are diagnosed more often in children than in adults. Treatment of giant aneurysms is carried out both by endovascular and microsurgical methods. Literature information on ...combination of microsurgical and endovascular operations of cerebral aneurysms at children is little. A clinical case of the combined treatment of a giant bicameral fusiform partially thrombosed aneurysm of the right vertebral artery at a 12-year-old patient and a literature review on this topic are presented. The patient underwent several complex neurosurgical interventions during two operations: 1) microsurgery including revascularization of the right posterior lower cerebellar artery, thrombectomy and trapping of the larger chamber of fusiform aneurysm of the right vertebral artery, and 2) endovascular, which consists in the installation of redirecting stent from the left vertebral artery to main artery. The uniqueness of the case which we presented lies in the fact that the tactics of stage combined treatment for a complex aneurysm at child was originally planned and successfully implemented. The treatment allowed to ensure a complete shutdown of aneurysm and to exclude postoperative cerebral complications.
OMEGA EP (extended performance) is a petawatt-class addition to the existing 30-kJ, 60-beam OMEGA Laser Facility at the University of Rochester. It will enable high-energy picosecond backlighting of ...high-energy-density experiments and inertial confinement fusion implosions, the investigation of advanced-ignition experiments such as fast ignition, and the exploration of high-energy-density phenomena. The OMEGA EP short-pulse beams have the flexibility to be directed to either the existing OMEGA target chamber, or the new, auxiliary OMEGA EP target chamber for independent experiments. This paper will detail progress made towards activation, which is on schedule for completion in April 2008.
Treatment of cerebral aneurysms in the acute stage of subarachnoid hemorrhage (SRH) especially on the background of cerebral vasospasm continues to be a difficult task.
Assessment of dynamics of the ...surgical treatment results of patients with cerebral aneurysms in acute period of SRH.
A comparative analysis of the results of patients' surgical treatment in NMRCN Burdenko about aneurysm in 1-21 days after hemorrhage was made. The following periods were selected: 2006-2014 (343 patients) and 2015-2018 (356 patients). Most patients had microsurgical operations in both periods. The tactics of choosing the surgery time was the main difference between the periods: particularly in 2015-2018 period the surgery was not postponed at patients with severe.
Analysing the post surgical mortality, it was found that since 2006 there is a consistent trend towards a decrease in the number of patients who died after surgery. When calculating the average post surgical mortality for the studied periods this trend is confirmed - number of lethal cases in 2015-2018 reliably decreased when comparing with 2006-2014 - from 6.8 till 3.2%; p=0.03. At the same time, the number of patients with outcome of vegetative status (from 0.3 till 5%).
The tactics of surgical treatment of patients with cerebral aneurysms in the acute period of SRH regardless of severity of patient's condition and time of hemorrhage did not lead to worse treatment. In contrast, post surgical mortality rates show a consistent decline. We associate this fact with a number of changes that have occurred in the management and treatment of patients. In particular, we have high hopes for developing new approaches to the treatment of vasospasm, which remains the leading cause of lethal cases. More definite conclusions will be made at the end of the treatment analysis of the respective patient groups.
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