Cranial Angle Research Articles

Enhancing Sex Estimation Accuracy with Cranial Angle Measurements and Machine Learning.

The development of current sexing methods largely depends on the use of adequate sources of data and adjustable classification techniques. Most sex estimation methods have been based on linear measurements, while the angles have been largely ignored, potentially leading to the loss of valuable information for sex discrimination. This study aims to evaluate the usefulness of cranial angles for sex estimation and to differentiate the most dimorphic ones by training machine learning algorithms. Computed tomography images of 154 males and 180 females were used to derive data of 36 cranial angles. The classification models were created by support vector machines, naïve Bayes, logistic regression, and the rule-induction algorithm CN2. A series of cranial angle subsets was arranged by an attribute selection scheme. The algorithms achieved the highest accuracy on subsets of cranial angles, most of which correspond to well-known features for sex discrimination. Angles characterizing the lower forehead and upper midface were included in the best-performing models of all algorithms. The accuracy results showed the considerable classification potential of the cranial angles. The study demonstrates the value of the cranial angles as sex indicators and the possibility to enhance the sex estimation accuracy by using them.

The validation of morphometric outcomes and stratification system for nonsyndromic sagittal craniosynostosis following total calvarial remodeling

This study aimed to provide an external validation of morphometric outcomes, including recently developed parameters — vertico-longitudinal index (VLI) and vertex-nasion-opisthocranion (VNO) angle — along with a proposed stratification system for nonsyndromic sagittal craniosynostosis (NSC). Thin-cut CT scans performed before and after total calvarial remodeling in 70 NSC children (mean preoperative age, 7.0 months; mean postoperative age 23.8 months) were evaluated. The parameters, including linear dimensions, morphometry-based indices, and cranial angles, were measured at the cranial vault and base. Each patient was also assigned a scaphocephaly severity score (SSS). The obtained data were compared with an age-matched control group of 80 normocephalic children.After surgery, all dimensions of the cranial vault increased, but did not normalize (p < 0.0001). Contrarily, some normalization was noted in the skull base, within the anterior and posterior cranial fossae. Postoperative results confirmed the diagnostic cut-off level for VNO at 50°; however, the proposed VLI cut-offs skewed the accuracy of SSS in the control group.To the best of our knowledge, this study was the first to discuss the value of an NSC stratification system in relation to underlying components. The SSS has a relevant background, but its accuracy would increase with a redefinition of normative VLI ranges.

Does the Angulation of the Screws in the Zero-P Implant Affect the Clinical and Radiological Outcomes of Patients?

When implanting the Zero-P device, the screws of Zero-P form a bone wedge with a 40 ± 5° cranial and caudal angle (CCA). However, no study has been performed in the optimal CCA of the Zero-P implant. To investigate whether the cranial/caudal angles (CCA) of the screws affect the clinical and radiological outcomes in patients undergoing ACDF with the Zero-P implant. From January 2016 to December 2023, we retrospectively analyzed 186 patients who underwent 1-level ACDF with the Zero-P device. The patients were divided into four groups: group A (cranial angle ≤40°, caudal angle ≤40°); group B (cranial angle ≤40°, caudal angle >40°); group C (cranial angle >40°, caudal angle ≤40°); and group D (cranial angle >40°, caudal angle >40°). The clinical outcomes, including Japanese Orthopaedic Association (JOA), neck disability index (NDI), and visual analogue scale (VAS) scores, the radiological parameters, including cervical lordosis (CL), cervical lordosis of operated segments (OPCL), intervertebral space height (ISH) and fusion rate (FR), and the complications, were evaluated and compared. Parametric tests, non-parametric tests, and chi-square tests were conducted to analyze the data. The OPCL of group A was significantly less than that of the other groups at the final follow-up (p < 0.05). The ISH of group D was significantly less than that of group A at the final follow-up (p < 0.05). The subsidence rate of group A was significantly less than that of group D at the final follow-up (p < 0.05). At the final follow-up, the upper adjacent-level degeneration (ASD) of group D was significantly less severe than that of groups A and B (p < 0.05). The clinical outcomes do not differ among groups (p > 0.05). A larger CCA of the screws (cranial angle >40°, caudal angle >40°) was better for maintaining OPCL and reducing the incidence of ASD. A smaller CCA of the screws (cranial angle ≤40°, caudal angle ≤40°) was better for maintaining ISH and reducing the rate of subsidence.

Carotid web catheter angiography hemodynamic parameters

BackgroundCarotid web (CaW)-related contrast stagnation on digital subtraction angiography (DSA) may be a marker supporting the pathophysiological theory of stasis and thrombosis/embolization. We aim to assess the correlation between DSA...

Effect of Cervical Index Changes on Cervical Pain

Background: The study of the angles between the vertebrae and the curvatures of the spine plays an important role in the pathogenesis of spinal disorders. The nature of the cervical region makes it susceptible to various cervical disorders, many of which can be caused by imbalanced alignment. Methods: In the present study, patients with chronic neck pain were compared with the normal population for cervical indexes. Results: One hundred subjects were selected, including 57 males (57%) and 43 females (43%). Neck tilting was significantly lower in the case group than control (41.5 vs. 45.8) (p=0.01). The mean of C0-C2 angle did not differ between groups (p=0.503), however, a significant increase was found for C2-C7 and C0-C7 angles (p=0.012) and (p=0.05), respectively. Further analysis revealed that cranial offset (21.9 vs. 8.6) and cranial tilting (21.3 vs. 10.1) significantly increased in patients with chronic neck pain (p&lt;0.001) and (p=0.004), respectively. Also, cervical Sagittal Vertical Axis (SVA) has shown a significant increase in patients than control (24.8 vs. 9.7) (p&lt;0.001). Conclusion: The data have indicated that cervical indexes. Thus, spine surgeons should obtain standing cervical radiographs and evaluate the relationship between T1 slope, Spino Cranial Angle (SCA), and cSVA in all cases affected by cervical pathogenesis, even without obvious deformity.

Abnormalities Detection in Apert Syndrome using Hierarchical Clustering Algorithms

Craniosynostosis syndrome is a congenital condition occurring due to the abnormal development of the skull, leading to abnormalities in skull morphology. Apert syndrome is one of common craniosynostosis syndrome in Malaysia and this syndrome can be categorized as the severe craniofacial disorders. The abnormalities of skull morphological in Apert syndrome patient can be identified as outliers which are investigated in this study. This study presents a skull morphological analysis based on a case study involving six paediatric patients diagnosed with Apert syndrome, alongside 22 control patients aged 0 to 12 years, all of whom underwent treatment at the University Malaya Medical Centre (UMMC). The computerized tomography scan (CTSCAN) data is provided by UMMC recorded from year 2012 until 2020 and the data is measured using MIMICS software by taking the measurement of cranial angles. The clustering-based procedures will be applied to identify the abnormalities in skull angle dataset. There are 12 skull angles and these angles are analysed using hierarchical clustering algorithms for identifying the outliers or abnormalities. The objective is to detect the abnormalities and determine the skull angles that associated with Apert syndrome (AS) in Malaysia population using clustering-based procedure. The abnormalities in Apert syndrome datasets are successfully detected by the algorithms and this study found that there are skull angles with specific location of angles are associated with Apert syndrome. This study also found that the location of skull angles for patients age 0-24 months old and &gt;24 months old are different. The findings of this study can assist the surgical team in directing additional focus towards specific regions of the skull during the planning of interventions. This guidance has the potential to optimize surgical outcomes and reduce the risk of potential complications.

Effects of telerehabilitation-based respiratory and corrective exercises among the elderly with thoracic hyper-kyphosis: a clinical trial

BackgroundAging is associated with changes in the musculoskeletal system, including increased susceptibility to spine malalignments. Utilizing corrective exercises with a therapeutic emphasis can be beneficial in the elderly with thoracic spine hyperkyphosis.ObjectiveThis study aimed to investigate the effects of six weeks of telerehabilitation-based respiratory and corrective exercises on quality of life, disability, thoracic kyphosis, craniovertebral angle, shoulder angle, cranial angle, and chest expansion in the elderly with thoracic spine hyperkyphosis.MethodsIn this clinical trial, a total of 40 participants aged 60 and above with thoracic hyperkyphosis were randomly divided into the control (N = 20) and experimental (N = 20) groups. The experimental group performed the corrective exercises for six weeks (3 sessions per week). The control group performed general stretching exercises during the same time period. We measured the outcomes of quality of life, disability, thoracic kyphosis, craniovertebral angle, shoulder angle, cranial angle, and lung expansion before and after the intervention. Analysis of covariance (ANCOVA) was employed to analyze the data. A P-value ≤ 0.05 was considered statistically significant.ResultsQuality of life (P < 0.001, Effect Size (ES): 0.44), chest expansion (P < 0.001, ES: 0.56), thoracic kyphosis angle (P < 0.001, ES: 0.31), craniovertebral (P < 0.001, ES: 0.33), cranial (P < 0.001, ES: 0.38), and shoulder (P = 0.005, ES: 0.20) angles were significantly improved in the experimental group as compared with controls. However, no statistically significant difference was observed between the two groups in terms of physical ability (P = 0.251, ES: 0.04).ConclusionIt is therefore recommended that online corrective exercises be used in the rehabilitation protocol to improve the quality of life, posture, chest expansion, and disability in the elderly with thoracic kyphosis.

Patient Cranial Angle and Intrafractional Stability in CyberKnife Robotic Radiosurgery: A Retrospective Analysis.

Purpose: The aim of this study was to investigate whether variations in cranial angles and treatment accuracy during CyberKnife robotic radiosurgery necessitate adjustment of the margins of the planning target volume. Patients and Methods: Data from 66 patients receiving CyberKnife treatment for brain tumors were retrospectively analyzed. Patients were immobilized using a thermoplastic mask and headrest. The cranial angle was measured on planning CT and patients were divided into 2 groups: ≤10° (Group A) and >10° (Group B). Intrafractional motion was recorded using the CyberKnife tracking system over 50 min. Translational and rotational errors were compared between groups, and planning target volume margins were calculated. Results: In Group A, significant translational error differences were found along with the X-axis over time (P < .02). In Group B, significant differences occurred along with the Z-axis (P < .03). No significant rotational or 3-dimensional vector differences were found in either group. Group A had significantly lower Y-axis (P < .045) and roll axis (P < .005) errors compared to Group B. Estimated planning target volume margins in Group A were 0.56 mm (X), 0.46 mm (Y), and 0.47 mm (Z). In Group B, margins were 0.62 mm (X), 0.48 mm (Y), and 0.46 mm (Z). Margins covering 95% of intrafraction motion were 0.49 to 0.50 mm (X, Y, Z) and 0.69 mm (3-dimensional vector) for Group A, and 0.48 to 0.60 mm and 0.79 mm for Group B. With a 1-mm margin, complete coverage was achieved in Group A while 2.1% of vectors in Group B exceeded 1 mm. Conclusion: Adjusting cranial angle to ≤10° during thermoplastic mask molding provided better or similar intrafractional stability compared to >10°.

Feasibility analysis and nail planning ofS2 iliac crest screw placement in children

To evaluate the feasibility of S2 alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters. A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S2 alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed. In all 83 children, 6.5 mm diameter S2 iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage. The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S2 alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.

Abstract 025: CTA carotid web structural characteristics as predictors for contrast stagnation on DSAs

Introduction Carotid webs (CaWs) have been shown to present with a long time of contrast stagnation during digital subtraction angiography (DSA) runs, and this has been proposed as a potential underlying physiopathological feature facilitating thrombosis and stroke. We aim to evaluate the relationship of quantified contrast stagnation with vascular imaging structural characteristics and clinical features of CaW. Methods We retrospectively assessed 48 patients with CaWs who underwent computerized tomography angiography (CTA) and DSA. CaWs’ structural characteristics were evaluated: 1) Length/Base/Thickness: base is the distance between the shoulders of the lesion, while the length is the distance between the midpoint of the base to the web apex. The thickness of the web is the length divided by the base; 2) Angles: we assessed three different web angles: caudal, middle, and cranial angles. All angles are referred to the axis of the vessel. The axis of the carotid is defined as the line spanning a specific length of 15 mm from the exact center of the distal common carotid artery to the center of the internal carotid artery;. The caudal angle is the angle between the line tangent to the caudal wall of the web and the vessel axis. The middle angle is the angle between the length of the web and the vessel axis. The cranial angle is the angle between the line tangent to the cranial wall of the web and the vessel axis. 3) Pocket Area/perimeter: these these measures were calculated by free‐hand delineation of delineating the web rostral surface of the web up to a straight line drawn at 90 degrees from the vessel axis of the carotid artery tangent to the web apex of the web through the vessel posterior wall. The perimeter is the perimeter of the hand‐delimited pocket area; 4) Orientation: it is the CaW ridge in relationship to the horizontal plane based on axial CTA cuts. A region of interest was placed in the DSA post‐web region, the mean Hounsfield units within the ROI was calculated for each frame of the run and a time density curve plotted. CaW structural measurementmeasurements were correlated with the hemodynamic parameters, such as stagnation time and area under the curve (AUC), and the hemodynamic parametersthese were correlated with clinical characteristics. Results Mean age of patients was 52.6 (±10 years), 32 (66.7%) were women, 40 (83.3%) were black, 29 (60.4%) had hypertension, 47 (97.9%) had stroke, from these, 89.4% had a large vessel occlusion. Base size had a weak correlation with AUC (p=0.02) and AUC from peak to 80% clearance (p&lt;0.01). No other correlations were found between CaW structural features (length, thickness, caudal, middle and cranial angles, pocket area and perimeter, and orientation) and hemodynamic parameters (stagnation time, stagnation time from peak to the point of 80% contrast clearance, AUC, and AUC from peak to the point of 80% of contrast clearance). Moreover, there are no correlations between those hemodynamic parameters with admission NIH, systolic or diastolic blood pressure, heart rate, clot burden, ASPECTS, automated CT cerebral perfusion defect volume [Tmax&gt;6 seconds], 90 day NIHSS, and 90 day mRS. Conclusion Base size was correlated with the AUC and AUC from the peak to the 80% clearance. No other hemodynamic parameters were correlated with the clinical characteristics. The relationship between DSA contrast stagnation and clinical outcomes remains unclear.

Abstract 224: Morphological characteristics of carotid webs associated with stroke risk and clot burden

Introduction Carotid webs (CaWs) have been established as an ischemic stroke etiology although lesion characteristics that may lead to increased stroke risk are still uncertain (1). We aim to evaluate the associations between CaW morphological features evaluated via computed tomography angiography (CTA) with clinical and radiological variables. Methods This is a retrospective analysis of a prospectively collected mechanical thrombectomy database. Individuals that presented with a suspected symptomatic CaW since July 2014 were selected after appropriate workup. The database included symptomatic CaW, asymptomatic CaW contralateral to the symptomatic side in case of bilateral lesions, and incidentally identified CaW (asymptomatic patients). We recorded the following CaW variables (Figure 1): length, base, thickness, caudal/middle/cranial angles in relationship to the vessel axis, area as well as perimeter of the pocket. We used mixed‐effects models to compare measurements between symptomatic and asymptomatic webs in the complete sample and paired Wilcoxon tests to compare webs of individuals with contralateral, symptom‐discordant CaW. Measurements were evaluated against clot burden via Poisson regression.a Results 118 webs (85 symptomatic and 33 asymptomatic) from 98 stroke patients were included. Median [IQR] for age was 52[42‐58] years old, 69.0% were female, 68.4% presented with a single symptomatic web, 18.4% had both a symptomatic and an asymptomatic web, 11.2% had only an asymptomatic web, whereas 2.0% had bilaterally asymptomatic webs. Symptomatic CaW were significantly larger in length (2.5mm[2.1‐3.5] vs. 2.2mm[1.7‐2.7];p=0.004) and pocket area (1.5mm²[0.9‐2.6] vs. 0.9 mm²[0.2‐1.3];p=0.007) compared to the asymptomatic lesions. The cranial angle was more acute for symptomatic CaW (66.9°[57.1°‐78.4°] vs. 76.2°[66.9°‐88.7°];p=0.046). No other significant associations were noted. Among the 18 patients who were analyzed for contralateral/symptom‐discordant webs, symptomatic CaW also showed more extensive lengths (2.9mm[2.3‐4.0] vs. 2.2mm[1.6‐3.1];p=0.009) but less acute rostral angles (33.1°[25.3°‐43.5°] vs. 27.9°[16.8°‐35.9°]) than their asymptomatic counterparts. Among symptomatic webs, clot burden was not significantly associated with base, length, thickness, perimeter or pocket area. Nevertheless, each 15° increase in the angle within the pocket was associated with a 1.1‐fold increase in clot burden (exp(β) = 1.1(95%CI1.0‐1.2), p = 0.044) for each 15° increase), with more obtuse angles indicating a higher intracranial vessel occlusion thrombus load. Conclusion Symptomatic carotid webs displayed larger lengths and pocket areas as compared to asymptomatic lesions. The angles that determine pocket area and degree of stenosis differed between symptomatic and asymptomatic webs.

PO-2259 Analysis of Patient Cranial Angle and Intrafractional Stability in CyberKnife Robotic Radiosurgery

PO-2259 Analysis of Patient Cranial Angle and Intrafractional Stability in CyberKnife Robotic Radiosurgery

Systematic review and meta-analysis on efficacy of various exercise programs to improve postural parameters, pain and disability in neck

Forward head posture is a common abnormal posture characterised by weakness of muscle around neck and shoulder. Persistent forward head posture can impair respiratory functions and cervical proprioception. The aim of this systematic review and meta-analysis is to determine the effectiveness of exercises to improve the forward head posture. The online literature search performed on various databases, i.e. PubMed, Cochrane, PEDro, Science Direct and Scopus databases resulted in 601 articles, but only 11 articles were found relevant to perform meta-analysis. The primary outcome measure was craniovertebral angle and other outcome measures were neck pain, cranial angle, cranial rotation angle and Neck Disability Index (NDI). Methodological quality of studies was assessed by PEDro scoring and risk of bias assessment was performed using Cochrane collaboration tool of risk of bias. Results of meta-analysis revealed that craniovertebral angle (CVA), cranial rotation angle (CRA), visual analogue scale and NDI improved significantly (P&lt;0.00001) in forward head posture participants who followed any type of exercise regime compared to the participants who did not follow any exercise program. However, cranial angle was not found significantly (P=0.73) improved in exercise groups. Exercises are effective in improving postural parameters, such as CVA, CRA and pain and neck disability in subjects with forward head posture. Systematic analysis registry at PROSPERO: CRD42020175372

Correlation between direction of pedicle screw and restoration of lumbar degenerative scoliosis in degenerative lumbar spondylolisthesis: a retrospective study.

Inferior clinical outcomes have been reported in patients with degenerative lumbar spondylolisthesis (DLS) accompanied by lumbar degenerative scoliosis, but little attention has been paid to its radiologic assessment or preoperative planning. The aim of this study was to analyze the effect of transforaminal lumbar interbody fusion on patients with DLS and lumbar degenerative scoliosis and explore the surgical aspects benefiting the restoration of lumbar degenerative scoliosis. All patients with DLS and lumbar degenerative scoliosis undergoing single-level unilateral transforaminal lumbar interbody fusion surgery between July 1, 2015, and April 30, 2021, were screened in this retrospective cohort study. Clinical outcomes including visual analog scale (VAS), Oswestry disability index (ODI), and radiographic parameters of sagittal and coronal alignment, cage spatial locations, and angle of pedicle screw (parallel, cranial, and caudad angle) were assessed. Coronal asymmetry was demonstrated by the intervertebral height difference between the medial and lateral margins of indexed intersegmental space. The correlations between Δintervertebral height difference (postoperative intervertebral height difference-preoperative intervertebral height difference) and radiographic parameters and clinical outcomes were analyzed by univariable, multivariable, mediation, and correlation analyses. Significance was set at a bilateral P<0.05. A total of 57 included patients were followed up for a minimum of 1 year. Reduction of VAS, ODI, and improvement of radiographic parameters were found after surgery. The cranial angle of the lower pedicle screw positively correlated with Δintervertebral height difference restoration (b=0.54; standard error=0.11; P<0.001). Transforaminal lumbar interbody fusion surgery appears to be an effective approach to improving the radiographic and clinical outcomes of patients with DLS and lumbar degenerative scoliosis. The cranial direction of the lower pedicle screws in single-level unilateral transforaminal lumbar interbody fusion surgery may be associated with a better postoperative restoration of lumbar degenerative scoliosis.

Cortical screw placement with a spinous process clamp guide: a cadaver study accessing accuracy

Background and objectiveThe Cortical Bone Trajectory (CBT) technique provides an alternative method for fixation in the lumbar spine in patients with osteoporosis. An accuracy CBT screw placement could improve mechanical stability and reduce complication rates.PurposeThe purpose of this study is to explore the accuracy of cortical screw placement with the application of implanted spinous process clip (SPC) guide.Methods and materialsFour lumbar specimens with T12-S1 were used to access the accuracy of the cortical screw. The SPC-guided planning screws were compared to the actual inserted screws by superimposing the vertebrae and screws preoperative and postoperative CT scans. According to preoperative planning, the SPC guide was adjusted to the appropriate posture to allow the K-wire drilling along the planned trajectory. Pre and postoperative 3D-CT reconstructions was used to evaluate the screw accuracy according to Gertzbein and Robbins classification. Intraclass correlation coefficients (ICCs) and Bland–Altman plots were used to examine SPC-guided agreements for CBT screw placement.ResultsA total of 48 screws were documented in the study. Clinically acceptable trajectory (grades A and B) was accessed in 100% of 48 screws in the planning screws group, and 93.8% of 48 screws in the inserted screws group (p = 0.242). The incidence of proximal facet joint violation (FJV) in the planning screws group (2.1%) was comparable to the inserted screws group (6.3%) (p = 0.617). The lateral angle and cranial angle of the planned screws (9.2 ± 1.8° and 22.8 ± 5.6°) were similar to inserted screws (9.1 ± 1.7° and 23.0 ± 5.1°, p = 0.662 and p = 0.760). Reliability evaluated by intraclass correlation coefficients and Bland–Altman showed good consistency in cranial angle and excellent results in lateral angle and distance of screw tip.ConclusionsCompared with preoperative planning screws and the actually inserted screws, the SPC guide could achieve reliable execution for cortical screw placement.

Embarrassed Radiofrequency Catheter Ablation of Supraventricular Tachycardia in Pectus Excavatum

A 16-year-old patient with pectus excavatum visited our hospital because of palpitation. He underwent first Nuss operations at the age of 3. When he was 13 years old, the slow-fast type atrioventricular nodal reentrant tachycardia was documented during electrophysiology study. However, the catheter ablation was not conducted because of recurrent atrial fibrillation during procedure. At that time, second Nuss operation was performed due to progressive chest wall deformity. And then, atrioventricular nodal reentrant tachycardia was successfully treated by radiofrequency catheter ablation at the higher position than usual slow pathway zone under the modified fluoroscopic view with the cranial angle although distorted right atrial geometry and radiographic obstacle of Nuss operation bar. The concern about abnormal cardiac and electrical anatomy, and the accurate and modified procedure technique are essential in patients with pectus excavatum. (Ewha Med J 2022;45(3):e6)

Does the asymmetry and extension function of the preoperative cervical paraspinal extensor predict postoperative cervical sagittal deformity in patients who undergo modified laminoplasty?

BACKGROUND CONTEXTA previous study found that the cross-sectional area (CSA) of the preoperative cervical paraspinal extensors (CPEs) was associated with loss of cervical lordosis after laminoplasty, while a recent study found that CPE asymmetry was associated with symptoms of degenerative cervical myelopathy. Whether preoperative CPE asymmetry can predict cervical sagittal deformity (CSD) after laminoplasty is unknown. PURPOSETo assess whether asymmetry, degree of degeneration, and extension function of the CPE can be used as predictors of postoperative CSD in patients who undergo laminoplasty. STUDY DESIGNA retrospective study. PATIENT SAMPLEFrom January 2017 to December 2019, 55 patients with multilevel cord compression and myelopathic symptoms were enrolled. OUTCOME MEASURESThe visual analog scale (VAS), neck disability index (NDI), and modified Japanese Orthopedic Association (mJOA) were used to assess cervical spinal function and quality of life. METHODSFrom January 2017 to December 2019, 55 patients undergoing modified laminoplasty were included. The following parameters were measured preoperatively and 24 months postoperatively on X-ray: (1) C0–C2 Cobb angle; (2) C2–C7 Cobb angle (CL); (3) T1 slope (T1S); (5) C2–C7 sagittal vertical axis (SVA); (6) T1S minus CL; (7) Preoperative extension function: Extension CL minus Neutral CL (EF). Preoperative global alignment parameters: (8) spino cranial angle, (9) C7-S1 sagittal vertical axis (C7 SVA), (10) pelvic incidence, (11) lumbar lordosis, (12) thoracic kyphosis. (13) Preoperative CPE parameters: Summation of bilateral total cross-sectional area (STCSA), summation of bilateral total cross-sectional area ratio (STCSAR), total cross-sectional area asymmetry, summation of bilateral functional cross-sectional area of muscle (SFCSA), summation of bilateral functional cross-sectional area of muscle ratio (FCSAR), and functional cross-sectional area of muscle asymmetry (FCSAA). The VAS, mJOA, and NDI were used to evaluate cervical spine function and quality of life. Patients were divided into the CSD group and the non-deformed group (N-CSD) group postoperatively, and the parameters between the two groups were compared. The Pearson correlation coefficient was used to evaluate the relationship between the parameters, and multiple regression analysis and ROC curve analysis were used to determine the predictors and key values. RESULTSCompared with functional scores, mJOA in the CSD group was significantly lower than that in the N-CSD group, while NDI and VAS were significantly higher. Postoperative CL was significantly correlated with EF, SFCSA/STCSA (C3–C6), SFCSAR (C4 and C6), STCSAR (C6), and FSCAA (C6). T1S minus CL was significantly correlated with EF, SFCSA/STCSA (C3–4 and C6), SFCSAR (C4 and C6), STCSAR (C6) and FSCAA (C6). C2–7 SVA was significantly correlated with EF, SFCSAR (C4 and C6), STCSAR (C6), and FSCAA (C6). Multiple regression analysis showed that FCSAA (C6), SFCSAR (C6), SFCSAR (C4), and EF were significant predictors of postoperative CSD. ROC curve analysis showed that the optimal cutoff points were 18.405, 2.95, 4.47, and 11.96. CONCLUSIONSThe present study found that preoperative extension dysfunction of CPEs, asymmetry at the C6 level cervical extensors, and cervical extensor CSAs without fatty infiltration at the C4 and C6 levels were associated with cervical sagittal imbalance after modified laminoplasty. These factors can be considered when future spine surgeons formulate surgical plans.

Posterior Atlantoaxial Screw Placement in a Portuguese Population: A Morphometric Analysis Based on Computed Tomography Scan Measurements.

Objective The present study aims to evaluate the screw length and trajectory angles for posterior atlantoaxial fixation in a Portuguese population, through the study of cervical computed tomography (CT) scans. Methods Cervical CT scans of 50 adults were measured according to predefined screw trajectories of C1-C2 transarticular (C1C2TA), C1 lateral mass (C1LM), C2 pedicle (C2P), C2 pars and C2 laminar (C2L) screws. For each of these trajectories, screw length and angles were measured and compared between males and females. Results For the C1C2TA screw trajectory, the mean length, medial, and cranial angles were 34.12 ± 3.19 mm, 6.24° ± 3.06, and 59.25° ± 5.68, respectively, and for the C1LM screw trajectory, they were 27.12 ± 2.15 mm, 15.82° ± 5.07, and 13.53° ± 4.80, respectively. The mean length, medial, and cranial angles for the C2P screw trajectory were 23.44 ± 2.49 mm, 27.40° ± 4.88, and 30.41° ± 7.27, respectively; and for the C2 pars screw trajectory, they were 16.84 ± 2.08 mm, 20.09° ± 6.83, and 47.53° ± 6,97. The mean length, lateral, and cranial angles for the C2L screw trajectory were 29.10 ± 2.48 mm, 49.80° ± 4.71, and 21.56° ± 7.76, respectively. There were no gender differences except for the lengths of the C1C2TA ( p = 0,020) and C2L ( p = 0,001) screws, which were greater in males than in females. Conclusion The present study provides anatomical references for the posterior atlantoaxial fixation in a Portuguese population. These detailed data are essential to aid spine surgeons to achieve safe and effective screw placement.

Cranial Morphology Associated With Syndromic Craniosynostosis: A Potential Detection of Abnormality in Patient's Cranial Growth Using Angular Statistics.

Apert, Crouzon, and Pfeiffer syndromes are common genetic syndromes related to syndromic craniosynostosis (SC), whereby it is a congenital defect that occurs when the cranial growth is distorted. Identifying cranial angles associated with these 3 syndromes may assist the surgical team to focus on a specific cranial part during the intervention planning, thus optimizing surgical outcomes and reducing potential morbidity. The aim of this study is to identify the cranial angles, which are associated with Apert, Crouzon, and Pfeiffer syndromes. The cranial computed tomography scan images of 17 patients with SC and 22 control groups aged 0 to 12 years who were treated in the University Malaya Medical Centre were obtained, while 12 angular measurements were attained using the Mimics software. The angular data were then divided into 2 groups (patients aged 0 to 24 months and >24 months). This work proposes a 95% confidence interval (CI) for angular mean to detect the abnormality in patient's cranial growth for the SC syndromes. The 95% CI of angular mean for the control group was calculated and used as an indicator to confirm the abnormality in patient's cranial growth that is associated with the 3 syndromes. The results showed that there are different cranial angles associated with these 3 syndromes. All cranial angles of the patients with these syndromes lie outside the 95% CI of angular mean of control group, indicating the reliability of the proposed CI in the identification of abnormality in the patient's cranial growth.

Correlation between the Photographic Cranial Angles and Radiographic Cervical Spine Alignment.

The cranial vertical angle (CVA) and cranial rotation angle (CRA) are used in clinical settings because they can be measured on lateral photographs of the head and neck. We aimed to clarify the relationship between CVA and CRA photographic measurements and radiographic cervical spine alignment. Twenty-six healthy volunteers were recruited for this study. Lateral photographs and cervical spine radiographs were obtained in the sitting position. The CVA and CRA were measured using lateral photographs of the head and neck. The C2-7 sagittal vertical axis (SVA), cervical lordosis (C2-7), and occipito-C2 lordosis (O-C2) were measured using radiographic imaging as a standard method of evaluating cervical spine alignment. Correlations between the CVA and CRA on photographs and cervical spine alignment on radiographs were analyzed. The CVA and SVA were significantly negatively correlated (ρ = −0.51; p < 0.05). Significant positive correlations were found between CVA and C2-7 (ρ = 0.59; p < 0.01) and between CRA and O-C2 (ρ = 0.65; p < 0.01). Evaluating the CVA and CRA on photographs may be useful for ascertaining head and neck alignment in the mid-lower and upper parts of the sagittal plane.