Maximum Safety Limits of Laminectomy of the C1 Vertebra for Chiari Malformation Surgery: A Finite Element Analysis.

Background: The treatment of Chiari malformations generally consists of posterior fossa decompression. C1 laminectomy is required in selected cases. However, cases of iatrogenic anterior arch fractures at C1 without high-energy trauma have been reported. Developing theoretical models of atlas C1 bones that have undergone a laminectomy can help researchers identify the regions where fractures may occur as a result of sudden loads. Methods: In this study, we created a detailed three-dimensional solid finite element model of the human atlas bone (C1) using geometric data. The loadings of the laminectomy dimension were evaluated on the basis of three groups. Group I comprised atlas bones that had not undergone a laminectomy. For Group II, the lateral border of the laminectomy was determined as the projection of the lateral mass medial border on the lamina. For Group III, the bilateral sulcus arteriosus was determined as the border for the lateral border of the laminectomy. The analysis results, which are in good agreement with those of previous reports, showed high concentrations of localized stress in the anterior and posterior arches of the atlas bone. Results: The analysis results showed that the stress increased in the laminectomy models. The maximum stress observed was consistent with the clinical observations of fracture sites in previous studies. Conclusion: In the treatment of patients with Chiari malformations, C1 laminectomy is often required. The width of this laminectomy can lead to iatrogenic anterior arch fractures. This is the first study to evaluate C1 laminectomy width using finite element modeling.

Increased Neutrophil Lymphocyte Ratio Could be Predictive for Higher Mortality in Preterm Infants with Intraventricular Hemorrhage.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) is a simple, cost-effective index of inflammation that can be measured by peripheral blood count. This study aimed to reveal that a high NLR value could be a prognostic marker for mortality risk in preterm babies born with IVH. METHODS: Preterm babies who had been followed up in the neonatal intensive care unit (ICU) between 2018 and 2020 were included in the study. These patients were examined in two groups, those who had had IVH and those who had not. The patients were evaluated by the week of birth, gender, first-minute APGAR score and NLR obtained from the first postnatal peripheral blood sample. RESULTS: A total of 113 babies had been born preterm and had been treated in the newborn intensive care unit (NICU) were included in the study. Intraventricular hemorrhage (IVH) was observed in 26 (23%) of the infants, and a total of 14 (12.4%) died, with the mortality rate being higher among those with IVH than those without (P = 0.026). There was also a statistically significant difference in the NLR between infants with IVH who died and those who did not (P < 0.001). NLR above 1.5 had 33.7 times higher risk of mortality compared to those with an NLR of 1.5 or below. CONCLUSIONS: This was the first study to examine the relationship between the NLR and mortality in preterm babies with IVH. This study showed that a high NLR was strongly associated with mortality in premature infants with low APGAR scores and having IVH.

Compliance with PECARN head injury decision rules in children under two years old.

BACKGROUND: One of the most common complaints about presentation at the Emergency Department (ED) in childhood is minor head trauma. In recent years, clinical decision rules (CDRs) have been published to assist in determining the need for performing computed tomography (CT) in these patients. The present study aims to investigate the compliance with Pediatric Emergency Care Applied Research Network (PECARN) rules in the decisions for CT examination in children aged below two years old with minor head trauma in our center. METHODS: This retrospective, single-center study was conducted on a patient group aged below two years old, who presented at the ED within 24 hours of a trauma incident and were diagnosed as mild head trauma Glasgow Coma Scale score 14 and 15). RESULTS: A total of 262 patients were included in this study. Of these patients, 214 (81.7%) received CT examination, and 48 (18.3%) patients did not receive any CT examination. None of these 48 patients showed clinically important traumatic brain injury (ci TBI). Among 214 patients who received CT examination, 89 (34%) patients met the PECARN rules criteria and 125 (47.7%) patients did not meet PECARN rules criteria. None of the patients who received CT examination and did not meet the PECARN rules criteria showed ci TBI. Among 89 patients who recieved a CT examination and also met the PECARN rules criteria, only 4 (1.5%) patients showed ci TBI. According to these results, the rate of compliance with PECARN rules in our institution ED was 52.3%. CONCLUSION: In this study, which was conducted by including all the predictor values of the PECARN guidelines, the rate of compliance with PECARN rules was determined to be very low. Using these rules directly or with modification could establish a starting point for clinicians to reduce the rates of unnecessary CT scans. However, the effects of the clinician's experience, parental expectations, medicolegal constraints and economic factors on the decision making process should not be forgotten.