Endogenous and Exogenous Factors Affecting the Surgical Technique (Review).

In this review, we analyzed essential factors affecting precise manual movements in microsurgery described in the medical literature. The search for publications in English and Russian languages was conducted in the PubMed database without limitation by the date of publication. The search was carried out according to the following descriptors: surgical procedures, dexterity, microsurgery, caffeine, alcohol, nicotine, physical exercise, sleep deprivation, posture. Only randomized and cohort studies involving doctors and students with surgical specialties were included in the analysis. We did not include papers in which only psychological (non-motor) aspects were studied. Due to the limited number of publications meeting the inclusion criteria and conflicting results in some of them, the presented review does not allow us to formulate unambiguous conclusions and recommendations. Further studies (deep and fundamental) of endogenous and exogenous factors affecting the microsurgical technique are needed.

[Long association tracts of the human white matter: an analysis of 18 hemisphere dissections and in vivo HARDI-CSD tractography]. / Dlinnye assotsiativnye provodyashie puti belogo veshchestva golovnogo mozga cheloveka: analiz dissektsii 18 polusharii i HARDI-CSD traktografii in vivo.

BACKGROUND: Anatomy of the conduction tracts of the cerebral cortex has been studied for a long time. Invention of diffusion tensor tractography renewed interest in this subject. The objectives of this work were to develop and improve protocols for dissection of the long association tracts of the human brain with studying the features of their segmentation, topography, and variability, compare the obtained data with the MR tractography data, and prepare for further clinical and anatomical studies. MATERIAL AND METHODS: We used 18 cerebral hemispheres (from 10 males and 8 females; 9 left and 9 right hemispheres). The mean age of cadavers was 68 years. Specimen were fixated in accordance with the Klingler technique. Immediately after collection, specimens were placed in a 10% formalin solution for at least 4 weeks. After that, the pia was removed; specimens were frozen at -20 °C for a week and then unfrozen in a 96% ethanol solution for a day. We performed 10 lateral dissections, 2 lateral dissections with isolation of the frontal aslant tract, 2 basal dissections, 1 combined basolateral dissection, 2 frontal dissections, and 1 medial dissection. At the time of dissection and after it, specimens were stored in a 96% ethanol solution. Modified, disposable, therapeutic wooden spatulas were used for manipulations. A microscope (magnification of 6-40x) was used in 2 lateral and 2 basal dissections. MR tractography (HARDI-CSD) was carried out in 5 healthy volunteers using a GE Signa HDxt MRI scanner a field strength of 3.0 T. RESULTS: We clearly identified the following fascicles: the arcuate fascicle (AF) and superior longitudinal fascicle (SLF) in 6/6 hemispheres on the right and in 5/6 hemispheres on the left, the inferior longitudinal fascicle (ILF) in 3/6 hemispheres on the left and in 4/6 hemispheres on the right, the uncinate fascicle (UF) in 4/4 hemispheres on the left and in 4/4 hemispheres on the right, and the inferior fronto-occipital fascicle (IFOF) in 4/4 hemispheres on the left and in 3/4 hemispheres on the right. Identification was less successful in the case of the frontal aslant tract (FAT) in 1/2 hemispheres on the left and in 0/2 hemispheres on the right. The used technique failed to identify the vertical occipital fascicle (VOF) of Wernicke, a segment of the superior longitudinal fascicle SLF I, and the middle longitudinal fascicle (MdLF). The MR tractography HARDI-CSD data were compared with the dissection data. We described in detail segmentation of the superior longitudinal, arcuate, and inferior fronto-occipital fascicles. Contradictory data were obtained for the superior longitudinal fascicle: a two-segment structure (SLFh and SLFv) was found in most (10/12) specimens, while a three-segment structure was revealed in the other (2/12) specimens (identified SLF II and SLF III). In the arcuate fascicle, the ventral and dorsal segments were successfully identified in 2/12 cases (1 left and 1 right), whereas identification failed in the other cases. During dissection of the inferior fronto-occipital fascicle, we could identify its surface layer in 1 of 8 cases (left) and its deep layer in one more case (left). CONCLUSION: Examination of the long association tracts using the Klingler technique has significant limitations in the fiber intersection areas (sagittal striatum). The frontal aslant tract was least studied; we proposed a special anterior dissection technique for its isolation. The superior longitudinal fascicle can have both the two-segment (10/12) and three-segment (2/12) structure. Investigation of the segmental anatomy of the long association tracts will be continued in further dissections. When planning neurosurgical interventions in the projection areas of the long association tracts, both preoperative HARDI-tractography and anatomical dissections ex vivo, based on the proposed protocols, can be recommended for the operating surgeon to master a three-dimensional picture of the tract topography.

[The clinical picture of nonsyndromic craniosynostosis in children].

OBJECTIVE: to study clinical presentations of nonsyndromic craniosynostosis (NCS) in children. MATERIAL AND METHODS: Authors analyzed 56 cases of different forms of NCS. To verify the diagnosis, all children underwent computed tomography with 3D cranial reconstruction. RESULTS AND CONCLUSION: The distribution of diagnoses was as follows: scaphocephaly - 28 (50%) patients, trigonocephaly - 21 (38%), different forms of plagiocephaly - 7 (12%). On admission to the hospital, 25 (43%) patients were diagnosed with perinatal CNS damage, 10 (18%) were born premature, 33 (59%) had neurological deviations. The clinical picture of NCS was polymorphic that might explain an increase in the number of children with late-diagnosed craniosynostosis. The early diagnosis of NCS which is the basis for using less invasive surgical methods is particularly important for prognosis.

[Biportal endoscopic removal of choroid papilloma of the lateral ventricle in a child].

The article is devoted to the use of minimally invasive techniques for removing intraventricular tumors; this topic is currently relevant to pediatric neurosurgery. As an example, a clinical case of complete removal of a choroid plexus papilloma in a child using the neuroendoscopic technique through the biportal approach is provided. This tumor is most commonly found in pediatric practice. Taking this into account, the use of minimally invasive surgical methods for treating this pathology is very important. The published data relating to this pathology, as well as to the use of neuroendoscopy for this disease, are fragmentary today. Therefore, one of the objectives of this work was to analyze the literature regarding etiopathogenesis, clinical presentation, diagnostic features, and some aspects of surgical treatment of choroid plexus papilloma, in connection with which this work is primarily of practical interest.

[Surgical aspects of endoscopic treatment of sagittal craniosynostosis (scaphocephaly) in children].

The article is devoted to the surgical treatment of sagittal craniosynostosis in children. Among non-syndromic monosynostosis sagittal craniosynostosis (scaphocephaly) is the most common. Treatment of children with craniosynostosis should begin as soon as possible. Endoscopic method refers to minimally invasive technique in surgical correction of craniosynostosis. This article presents a features of surgical treatment at all stages of the endoscopic cranioplasty. Presented data is based on the experience of treatment of 20 children with primary sagittal craniosynostosis. Treatment was performed using endoscopic techniques, special tools designed specifically for the endoscopic cranioplasty.