[Factors of endoscopic third ventriculostomy efficacy in infants with obstructive hydrocephalus under one year of age]. / Faktory éffektivnosti éndoskopicheskoi ventrikulostomii dna III zheludochka u detei do odnogo goda s okkliuzionnoi gidrotsefaliei.

Endoscopic surgery for obstructive hydrocephalus in children is an alternative to shunts. Currently, the efficacy of endoscopic third ventriculostomy (ETV) in infants up to one year of age is increasingly discussed among neurosurgeons. To increase the efficacy of ETV, many surgeons raise the question: what factors may affect the efficacy of this procedure in the younger age group? OBJECTIVE: To study the factors affecting the efficacy of ETV. MATERIAL AND METHODS: A total of 88 ETVs were performed in infants under one year of age in our clinic in 2012-2016. Subsequently, 43 (48.9%) children underwent CSF shunting, and one child underwent repeated ETV. The mean time until the appearance of clinical signs of stoma closure was 3.9 months (116 days). RESULTS: The procedure was most effective in the case of congenital obstructive hydrocephalus (64.5% of successful operations) and also in children over the age of 6 months (63.6% of successful operations). The efficacy in post-hemorrhagic hydrocephalus was 40%. The efficacy in grade 4 intraventricular hemorrhage was lowest and amounted to 25%. The total efficacy of ETV in children under one year of age in our study was 51.1%. CONCLUSION: In the case of congenital obstructive hydrocephalus, the efficacy of ETV is maximal and amounts to 64.5%. To achieve the highest efficacy of ETV in infants under one year of age, careful selection of patients at the preoperative stage is necessary, with allowance for many factors affecting treatment outcome.

[Shunt-induced craniosynostosis: topicality of the problem, choice of the approach, and features of surgical treatment]. / Shunt-indutsirovannyi kraniosinostoz: aktual'nost' problemy, vybor taktiki, osobennosti khirurgicheskogo lecheniia.

RATIONALE: Shunt-induced craniosynostosis is one of the late complications of CSF shunting surgery, which affects the patient's condition, clinical picture, and treatment approach. OBJECTIVE: to evaluate the prevalence rate and clinical significance of this disease, define the indications for surgery, and choose the optimal surgical approach. MATERIAL AND METHODS: The study included 59 children with shunt system dysfunction, aged 1 to 14 years, who were treated at the Department in the period from 2014 to 2016. The inclusion criteria were as follows: 1) age at the time of examination is older than 1 year; 2) implantation of a shunt system in the first 12 months of life. The state of cranial sutures was assessed using three-dimensional reconstruction of patient's computerized tomography images. Images obtained before or in the first months after primary implantation of a shunt system were used to exclude cases of primary craniosynostosis. RESULTS: Premature synostosis of the cranial sutures was detected in 27 (46%) cases. Of these, 3 (11%) patients with clinical symptoms of increased intracranial pressure and radiographic signs of craniocerebral disproportion underwent cranial vault remodeling surgery: two biparietal craniotomies and one fronto-parieto-occipital reconstruction. In two cases, simultaneous replacement of a valve with a programmable one was performed. There were no complications after reconstructive surgery. CONCLUSION: Shunt-associated craniosynostosis is one of the late complications of CSF shunting surgery. However, its presence is not an indication for surgery and should not be a reason for surgical aggression. Surgery for increasing the intracranial volume is indicated only for secondary craniosynostosis combined with signs of craniocerebral disproportion. In these cases, reconstructive surgery is an effective treatment option for improving the patient's condition.

[The use of frameless navigation during endoscopic interventions in children with multilocular hydrocephalus].

INTRODUCTION: The use of the endoscopic technique largely improves treatment outcomes in patients with multilocular hydrocephalus. However, impaired anatomy and the lack of usual landmarks often cause problems in planning and intraoperative identification of changed structures. The use of frameless navigation during endoscopic interventions can significantly facilitate surgeon tasks and increases the efficacy of surgery. During surgery, the neuronavigation system visualizes a rigid endoscope that interconnects separated ventricles and cysts. Surgery can be completed with guiding a stent through an operating channel of the endoscope and implanting a shunt system. MATERIAL AND METHODS: Ten children underwent 11 endoscopic interventions using frameless intraoperative navigation at our clinic in 2013-2014. The number of surgically interconnected compartments ranged from 3 to 5. Simultaneous placement of a shunt system was performed in 8 of 11 interventions. RESULTS: Clinical improvement as a result of the operation was achieved in all children. 2 patients underwent re-operations 5 months and 1 year after endoscopic intervention. CONCLUSION: Thus, the use of frameless navigation during endoscopic interventions makes their implementation most efficient and safe for the patient.

Bioavailability of radiostrontium in soil: experimental study and modeling.

Parameters related to 90Sr mobility in the soil-plant system are reported: exchangeable content, selectivity coefficient, and transfer factor. Large mobility of 90Sr in different soil types was shown. The fraction of exchangeable 90Sr varied between 70 and 90%. The selectivity coefficient K(C)(90Sr/Ca) values were in the range 1.3-2.5. The radionuclide transfer factors (TF) varied by a factor of 9.6 for barley seedlings and by a factor of 6.6 for lupine seedlings. The exchangeable Ca content was the determinant soil parameter responsible for differences in 90Sr biological availability. A static model was devised that describes 90Sr sorption from soil solution by soil and on the root surface. The parameter of 90Sr bioavailability (A) has been suggested. Parameter A was calculated from data on soil exchangeable Ca content and 90Sr mobility indicators--exchangeable fraction of the radionuclide and the selectivity coefficient K(C)(90Sr/Ca). A correlation was found between TF and parameter A.