[Method for evaluating effectiveness of simulation trainings in surgical manipulations].

Performance of varies surgical manipulations (SM) is a key skill in surgery. To develop such skills simulation trainings (ST) are used, followed by a training transfer, which is the ultimate goal of ST However, this training goal is not always achievable - the share of doctors using laparoscopic intracorporal suturing after the training ranges from 43.8% to 72.2%. Therefore, to improve training transfer it is necessity to evaluate effectiveness of such training programs. Current methods evaluate training results either outside real practice or in practice but in small groups due to high cost and efforts consumed. The paper presents a new method to evaluate effectiveness of SM simulation training programs in general population of the trainees, evaluate additional effects of the training and analyze personal factors affecting the training results. The method is based on a survey of the ST program participants, and tested at the Training and Accreditation Center «Medical Simulation Center of the Botkin Hospital¼ within the program on laparoscopic intracorporal suturing. The rate of training transfer added up to 88.9%. The suggested method makes it possible to evaluate effectiveness of SM simulation training in general population of the trainees, analyze factors affecting the training results and use findings for improving ST programs and methods in general. The method can be recommended for a large-scale implementation in simulation training programs.

[Application of a modified Time-SLIP MRI sequence for visualization of cerebrospinal fluid movement in the cerebral aqueduct and cervical spinal canal]. / Primenenie modifitsirovannoi MRT-posledovatel'nosti Time-SLIP dlia vizualizatsii dvizheniia likvora v vodoprovode mozga i sheinom otdele pozvonochnogo kanala.

Direct visualization of rapid cerebrospinal fluid movements is a topical task of neurosurgery, which has applications such as evaluating hydrocephalus and the effectiveness of 3rd ventriculostomy. PURPOSE: The study purpose was to evaluate the capabilities of a modified Time-SLIP pulse MRI sequence for visualization of fluid (CSF) movements in the phantom, healthy subject, and patient. MATERIAL AND METHODS: The study was performed in a phantom simulating pulsed CSF movements, healthy volunteers (9 people), and patients without impaired CSF dynamics (12 people), whose data were used to determine mean CSF flow parameters, as well as in 1 patient after 3rd ventriculostomy. A 1.5 T MRI instrument was used. The Time-SLIP parameters were as follows: TR = 8,500 ms; TEeff = 80 ms; Thk = 5.0 mm; tag spacing = 30 mm; NEX 7; inversion time (BBTI) = 2,000/3,000 ms; no cardiosynchronization. Scanning time was 2:16 min. The estimated parameter was the length of motion (LOM) of CSF. RESULTS: According to a study on a phantom simulating various conditions of oscillatory fluid motion, the mean LOM determination error in the modified Time-SLIP mode was 20%. This technique provided the following LOM data for the cerebral aqueduct (median, 25-75% quartiles): 13.0 (9.5-16.0) mm for BBTI of 2,000ms and 30.2 (23.7-35.3) mm for BBTI of 3,000 ms, i.e. 2.3-fold higher. This difference may be explained by an intense turbulent current leading to rapid CSF exchange between the 3rd and 4th ventricles and prolonged CSF movement during several heart contractions. Quantitative parameters of CSF movement at the C1-C2 level were determined. Additionally, Time-SLIP was used to evaluate performance of a third ventricle fistula. CONCLUSION: We have proposed a modified Time-SLIP pulse sequence that does not require cardiosynchronization. The mean relative error in determining the CSF movement distance was 20%. The mean quantitative parameters of CSF movement in the cerebral aqueduct and at the C1-C2 level were obtained. Turbulent CSF flow is found in the cerebral aqueduct, which leads to rapid exchange between the 3rd and 4th ventricles.