Establishing Safe Surgical Parameters for Placement of C2 Vertebra Pedicle Screws: A Retrospective Study

OBJECTIVE

The study aimed to evaluate the safety and feasibility of transpedicular instrumentation for the C2 vertebra and to establish the precise anatomical parameters and boundaries within which this procedure can be safely and effectively performed.

MATERIALS AND METHODS

This retrospective study analyzed 66 patients who underwent C2 transpedicular screw fixation. Preoperative and postoperative axial, sagittal, and coronal cervical computed tomography (CT) scans were examined. Anatomic measurements were taken to determine the horizontal and vertical distances from the C2 pedicle projection to the vertebral foramen using cervical CT images. Based on the anatomical location of the vertebral artery within the C2 vertebral foramen, the patients were divided into four subgroups using the horizontal pedicle width (HPW) and vertical pedicle width (VPW) of the C2 spine.

RESULTS

The average age of the patients included in the study was 46.48 years. Among the patients, 32 (48,5%) were male and 34 (51,5%) were female. Based on anatomical measurements, the distribution of C2 vertebra types was as follows: Type 1 accounted for 68,9%, Type 2 for 3,8%, Type 3 for 16,7%, and Type 4 for 10,6%. Significantly narrower pedicle widths were observed in Type 2 and Type 4 compared to other types. Type 2 had the largest medial angle (MA), while Type 4 had the narrowest MA. In terms of the sagittal plane, Type 4 exhibited the widest MA, and Type 3 had the narrowest MA, but these differences were not statistically significant. Among the cases, 12 (18,1%) involved the vertebral foramen, with one case (8,3%) showing screw-related vertebral artery injury (0.75% of all screws). No vertebral artery injuries were observed with the other transpedicular screws.

CONCLUSION

Preoperative anatomic measurements for patients undergoing transpedicular instrumentation on the C2 vertebra should include planning cervical CT images on three planes: axial, sagittal, and coronal.

Fusiform aneurysms of anterior cerebral artery: center experience and systematic literature review

Fusiform aneurysms of the anterior cerebral artery (ACA) are uncommon, and the natural history of this entity is poorly characterized. Along with our center experience, we conducted a systematic literature review to help shed light on the clinical course of ACA fusiform aneurysms. We queried our institutional database to identify cases with fusiform aneurysms of ACA. In addition, following the PRISMA algorithm, we identified all reported cases published in the English literature from the inception of PubMed until December 2022. We categorized clinical presentations into three categories: (i) traumatic/iatrogenic, (ii) spontaneous symptomatic ruptured/unruptured, and (iii) spontaneous asymptomatic aneurysms. We utilized descriptive statistics. We identified seven cases from our center along with 235 patients from published literature. Blunt trauma was responsible for the development of 19 aneurysms. Sixty-three percent of these aneurysms tend to rupture within 2 weeks from the initial trauma, and despite treatment, only 74% of these patients had good clinical outcomes. Spontaneous symptomatic presentation occurred in 207 patients and was often associated with previous/concomitant ACA dissection. Subarachnoid hemorrhage from ruptured aneurysms was the most common presentation. Spontaneous symptomatic fusiform aneurysm is rapidly evolving lesions, and treatment is necessary. Three of our own cases were treated with an endovascular flow diverter (pipeline) stenting with good outcomes. Spontaneous asymptomatic aneurysms were reported in nine patients. These lesions are often associated with other vascular abnormalities. Treatment included surgical clipping with good clinical outcomes. Instead, four patients from our center database were managed conservatively with equally good outcomes. Our study demonstrates good clinical outcomes when fusiform aneurysms of ACA, especially when symptomatic, are treated promptly with either reconstructive or deconstructive therapies.

High-resolution MRI to noninvasively characterize drainage around the carotid artery into the cervical lymph nodes

BACKGROUND AND PURPOSE

Previous studies have proposed multiple parallel channels for waste clearance from the brain, though many gaps remain in our understanding of these systems. In this study, we examined periarterial fluid drainage around intracranial and extracranial segments of the internal carotid arteries (ICAs) from the brain into the cervical lymph nodes using a noninvasive and clinical-based method.

METHODS

Eighty-one subjects (45 females, aged 15-80 years old) with nonlesioned epilepsy underwent high-resolution 3-dimensional T2-weighted fluid-attenuated inversion recovery (FLAIR) MRI. We utilized a noninvasive and clinical-based method with a manual semiautomated approach to characterize the periarterial lymphatic system's maximum thickness and signal intensities along the ICAs using high-resolution 3-dimensional FLAIR imaging. We conducted group comparisons and correlation analyses to investigate sex- and age-based trends. Results were corrected with Bonferroni's test for multiple comparisons, and we performed power analysis for sample size calculations.

RESULTS

Using high-resolution FLAIR images, we show evidence that fluid drainage emerges around the ICA petrous segment and joins lymphatic flow from cranial nerves in the upper neck, with this flow ultimately draining into the cervical lymph nodes bilaterally. Lymphatic signal at the petrous segment level was significantly thinner in females compared to males bilaterally (w = 413, p = .0001 on the right, w = 356, p < .0001 on the left). Lymphatic drainage around the petrous segments of the ICAs bilaterally was thicker with age in males but not in females.

CONCLUSIONS

We describe the in vivo high-resolution imaging characteristics of periarterial fluid drainage along the vessel walls of ICAs. This represents a potentially major channel for brain waste clearance. We also report interesting sex- and age-based trends in these structures within our cohort.

In Vitro Fertilization, Levels of Pro-Inflammatory Factors and Lipid Peroxidation

BACKGROUND

Infertility is a problem concerning 10-15% of the individuals in the fertile period. This study investigated effects of proinflammatory factors as well as lipid hydroperoxides (LPO) levels upon in vitro fertilization (IVF) success.

MATERIALS AND METHODS

In this prospective, non-randomized, controlled clinical study, sera obtained from 26 fertile (group-1), 26 infertile women before (group-2) and after (group-3) IVF treatment were analyzed. Leptin, leptin receptor, resistin, tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) were analyzed using enzyme-linked immunosorbent assay (ELISA). LPO was determined spectrophotometrically. Mann- Whitney U test, paired samples t test, Wilcoxon signed-rank test as well as Pearson correlation analysis by SPSS were performed for statistical analysis.

RESULTS

TNF-α, resistin and LPO levels increased (P=0.020, P=0.003, P=0.001, respectively) in group-3 compared to group-2. A significant increase in LPO was noted both in group-2 and -3 compared to controls (P=0.000). LPO were higher in non-pregnants than pregnants in group-2. For pregnants, significant correlations were observed between leptin and resistin in group-2 and TNF-α and leptin in group-3. None of these correlations were found for the women, who could not conceive.

CONCLUSION

LPO, leptin-resistin correlation, associations with TNF-α may be helpful during the interpretation of IVF success rates.

Association of fetuin A, adiponectin, interleukin 10 and total antioxidant capacity with IVF outcomes

BACKGROUND

Possible roles of anti-inflammatory factors as well as total antioxidative capacity in reproductive processes of women undergoing in vitro fertilization (IVF) are still being investigated and the contributions by some of them remain controversial.

OBJECTIVE

The aim of this study is to investigate the relationship between anti-inflammatory parameters and total antioxidative capacity (TAC) of the body during IVF. In this respect, adiponectin, interleukin-10 (IL-10), interleukin-1 receptor antagonist (IL-1RA), fetuin A and TAC analyses have been performed.

MATERIALS AND METHODS

In this prospective, non-randomized, controlled clinical study, sera obtained from 26 fertile (Group-1), and 26 infertile women before (Group-2) and after (Group-3) IVF treatment were analyzed. IL-1RA, IL-10, fetuin A, adiponectin and insulin were determined by ELISA. TAC was determined spectrophotometrically. Mann-Whitney U test, paired sample t-test, Wilcoxon signed-rank test as well as Pearson correlation analysis by SPSS were performed for statistical analysis.

RESULTS

Clinical pregnancy and live birth rates were determined as 30.8% and 23.1%, respectively, in pregnant group. For the pregnant, significant indirect correlations were detected between fetuin A and adiponectin (r=-0.843; p=0.035) as well as IL-10 (r=-0.846; p=0.034) in Group 2. The correlation between adiponectin and IL-10 doubled in pregnant compared to non-pregnant (r=0.929; p=0.007 vs. r=0.478; p=0.033). The correlations between fetuin A and TAC in pregnant were noted both in Group 2 (r=0.892; p=0.017) and Group 3 (r=0.875; p=0.022). No correlation of fetuin A with these parameters was detected in non-pregnant group.

CONCLUSION

Fetuin A, TAC, IL-10, adiponectin and their associations may be important from their predictive values for IVF success point of view. Parameters with anti-inflammatory or antioxidant property appear to improve pregnancy in women undergoing IVF.

Diffusion-weighted imaging findings in brain death

INTRODUCTION

The purpose of the present study was to determine the role of diffusion-weighted imaging (DWI) and to investigate the use of DWI in the diagnosis of brain death (BD).

METHODS

We prospectively evaluated 22 patients diagnosed with clinical BD (9 women, 13 men; mean age, 39.63 ± 15.1 years; age range, 9-66 years). All clinical criteria for BD were present in all 22 patients before magnetic resonance imaging, including a positive apnea test. For all cases, DW images, T2-weighted images, and fluid-attenuated inversion recovery were obtained. Thirteen distinct neuroanatomical structures were selected for analysis in all the cases. For each region of interest, the mean, standard deviation, and range of the average apparent diffusion coefficient (ADCav) values were obtained.

RESULTS

For BD patients, ADC values in all neuroanatomical structures were significantly lower than those for control subjects. We determined how ADC values in all structures were related to the diagnostic condition as well as the appropriate threshold ADC values to classify a subject as BD or control. The sensitivity, specificity, positive and negative predictive values, and correct classification rate of ADC cutoff values to distinguish BD from control groups were 100%.

CONCLUSIONS

DWI might be used as a noninvasive confirmatory test for the diagnosis of BD in the future.