Volume Asymmetry Research Articles

Morphological and metabolic asymmetries of the thalamic subregions in temporal lobe epilepsy predict cognitive functions

Both morphological and metabolic imaging were used to determine how asymmetrical changes of thalamic subregions are involved in cognition in temporal lobe epilepsy (TLE). We retrospectively recruited 24 left-TLE and 15 right-TLE patients. Six thalamic subnuclei were segmented by magnetic resonance imaging, and then co-registered onto Positron emission tomography images. We calculated the asymmetrical indexes of the volumes and normalized standard uptake value ratio (SUVR) of the entire and individual thalamic subnuclei. The SUVR of ipsilateral subnuclei were extensively and prominently decreased compared with the volume loss. The posterior and medial subnuclei had persistently lower SUVR in both TLE cases. Processing speed is the cognitive function most related to the metabolic asymmetry. It negatively correlated with the metabolic asymmetrical indexes of subregions in left-TLE, while positively correlated with the subnuclei volume asymmetrical indexes in right-TLE. Epilepsy duration negatively correlated with the volume asymmetry of most thalamic subregions in left-TLE and the SUVR asymmetry of ventral and intralaminar subnuclei in right-TLE. Preserved metabolic activity of contralateral thalamic subregions is the key to maintain the processing speed in both TLEs. R-TLE had relatively preserved volume of the ipsilateral thalamic volume, while L-TLE had relatively decline of volume and metabolism in posterior subnucleus.

Preoperative white matter network organization and memory decline after epilepsy surgery.

Risk for memory decline is a common concern for individuals with temporal lobe epilepsy (TLE) undergoing surgery. Global and local network abnormalities are well documented in TLE. However, it is less known whether network abnormalities predict postsurgical memory decline. The authors examined the role of preoperative global and local white matter network organization and risk of postoperative memory decline in TLE. One hundred one individuals with TLE (n = 51 with left TLE and 50 with right TLE) underwent preoperative T1-weighted MRI, diffusion MRI, and neuropsychological memory testing in a prospective longitudinal study. Fifty-six age- and sex-matched controls completed the same protocol. Forty-four patients (22 with left TLE and 22 with right TLE) subsequently underwent temporal lobe surgery and postoperative memory testing. Preoperative structural connectomes were generated via diffusion tractography and analyzed using measures of global and local (i.e., medial temporal lobe [MTL]) network organization. Global metrics measured network integration and specialization. The local metric was calculated as an asymmetry of the mean local efficiency between the ipsilateral and contralateral MTLs (i.e., MTL network asymmetry). Higher preoperative global network integration and specialization were associated with higher preoperative verbal memory function in patients with left TLE. Higher preoperative global network integration and specialization, as well as greater leftward MTL network asymmetry, predicted greater postoperative verbal memory decline for patients with left TLE. No significant effects were observed in right TLE. Accounting for preoperative memory score and hippocampal volume asymmetry, MTL network asymmetry uniquely explained 25%-33% of the variance in verbal memory decline for left TLE and outperformed hippocampal volume asymmetry and global network metrics. MTL network asymmetry alone produced good diagnostic classification of memory decline in left TLE (i.e., an area under the receiver operating characteristic curve of 0.80-0.84 and correct classification of 65%-76% of cases with cross-validation). These preliminary data suggest that global white matter network disruption contributes to verbal memory impairment preoperatively and predicts postsurgical verbal memory outcomes in left TLE. However, a leftward asymmetry of MTL white matter network organization may confer the highest risk for verbal memory decline. Although this requires replication in a larger sample, the authors demonstrate the importance of characterizing preoperative local white matter network properties within the to-be-operated hemisphere and the reserve capacity of the contralateral MTL network, which may eventually be useful in presurgical planning.

Longitudinal Comparison of Orbital Volumes from Enucleated Eyes with Hydroxyapatite Orbital Implant in Unilateral Retinoblastoma Patients.

To compare the orbital volume between enucleated and contralateral, uninvolved orbits over a 5-year period in patients with unilateral retinoblastoma who underwent enucleation with hydroxyapatite (HA) implant placement by a single surgeon. A retrospective review was performed on the clinical records and radiographic images of unilateral retinoblastoma patients who underwent enucleation with primary HA implantation from 2003 to 2020 at a single institution. Bilateral orbital volume measurements were taken from the initial postoperative MRI scan and again at 1- and 5-years postenucleation. The main outcome measure was the longitudinal change in volume difference (∆𝑉). The implant size, age at enucleation, and sex were also evaluated. A linear mixed-effect model was used for analysis. A total of 124 patients (73 males) with HA implants following enucleation were included. Overall, the unaffected orbit trended toward having a greater volume compared with the enucleated orbit, but this was not statistically significant (β = 0.003; p = 0.122). The mean age at enucleation was 2.4 years. The median time between enucleation and the initial, 1-year, and 5-year postoperative MRIs was 6 months, 17 months, and 55 months, respectively. There was no statistical correlation between age at enucleation, gender, implant size, or orbital volume at any time points ( p > 0.05). Patients treated with enucleation and primary HA implant placement for unilateral retinoblastoma did not display significant asymmetry in orbital volume on 5-year postenucleation MRIs, suggesting that HA implants promote orbital growth comparable to a nonenucleated orbit in the pediatric population.

Ventricular volume ratio as a novel imaging biomarker for disease prediction in 26,516 UK Biobank participants

Abstract Background/Introduction Right and left ventricular volumes are established imaging biomarkers for disease discrimination and outcome prediction. Limited research in select disease cohorts suggests additional clinical value from consideration of disproportionate (or imbalanced) dilatation of one ventricle over the other. The prognostic utility of this "ventricular volume ratio" (VVR) has not been tested in large, unselected cohorts. Purpose To examine associations of right-to-left and left-to-right VVR with cardiovascular phenotypes, prevalent disease, and incident cardiac outcomes in the UK Biobank. Methods The analysis includes 26,516 participants with cardiac magnetic resonance (CMR) available. We calculated right-to-left ventricular volume ratio (RV/LV), and the reciprocal left-to-right ventricular ratio (LV/RV), and identified participants with asymmetry above the 95th percentile of healthy cases. Multivariable linear and logistic regression models were used to calculate associations between ventricular volume asymmetry and sample characteristics, other cardiac imaging features, existing disease and incident disease. Incident disease associations were measured using Cox proportional hazards models adjusted by age, sex, systolic blood pressure, body mass index, smoking, Townsend deprivation score, hypertension, diabetes, hyperlipidaemia and other key imaging metrics (LV mass indexed to body surface area, LV ejection fraction and RV ejection fraction). The average follow-up time was 4.6 years (SD 1.3 years). Results Ventricular volume asymmetry in either direction was associated with increased age, lower RVEF, poorer LV global function index, poorer global longitudinal strain and greater maximum wall thickness. While RV-dominant volume asymmetry was associated with increased risk of all-cause mortality (HR= 1.56, 95% CI= [1.08, 2.26], p=0.019), LV-dominant volume asymmetry was found to associate with a much wider array of factors in the UK Biobank population. LV dominance was significantly associated with smoking, hypertension, diabetes, hyperlipidaemia, existing respiratory disease and existing heart disease. In fully-adjusted models, LV dominance was associated with increased risk for ischaemic heart disease (1.46 [1.12, 1.91], p=0.005), non-ischaemic cardiomyopathies (3.62, [1.93, 6.79], p < 0.001) and a two-fold increased risk for heart failure (2.30, [1.63, 3.26], p < 0.001). Conclusion(s) LV/RV is easily calculated from existing imaging metrics, and could potentially have important added value as a biomarker in predicting heart disease, incremental to well-established risk factors and imaging metrics.

53 REM Sleep Behavior Disorder in Parkinson’s Disease : Longitudinal Effects on Brain Lateralization

Objective:Laterality of motor symptom onset in Parkinson’s disease (PD) is well-known and under-appreciated. It is still unclear though if this laterality might have an influence on other symptoms. Specifically, REM sleep behavior disorder has been shown to be a factor that has a high probability to be lined to PD. In this study we analyzed the longitudinal effect of REM symptomatology on brain lateralization in PD.Participants and Methods:We used the baseline and 3-year visit data of 116 participants (67 without REM (PD-non-REM), 49 with REM (PD-REM)) aged 37-81 years from the Parkinson’s Progression Markers Initiative (PPMI) dataset. Statistical 3T MRI data (cortical thicknesses, areas, foldings of cortical Desikan atlas and volumes of subcortical regions) were obtained via FreeSurfer 7.1.1. Lateralization was computed using the formula: (left-right)/(lef +right). Mixed ANOVAs were performed on each region of interest.Results:Our findings showed an increased right asymmetry of the paracentral lobule area and of the pars orbitalis area and volume in PD-REM. There was a reduced right asymmetry of the parietal inferior volume at baseline in PD-REM, whereas REM symptomatology had a stable effect at the 3 years visit. At baseline, there was an increased left asymmetry of the thickness of the caudal anterior cingulate, pars orbitalis and pars triangularis regions in PD-REM. After 3 years, there was an increased right asymmetry in those regions. The precentral, frontal superior and transversal temporal gyri showed inverse results: an increased right asymmetry of the thickness at baseline and an increased left asymmetry after 3 years. Finally, REM symptomatology is associated with more significant increases of the left asymmetry of the frontal superior gyrus volume and of the right asymmetry of the supramarginal gyrus volume after 3 years than at baseline.Conclusions:These results provide evidence of the modulating effect of the disease progression on the relationship between REM symptoms and brain lateralization in PD.

Retracted: Lateral Ventricular Volume Asymmetry and Optic Nerve Sheath Diameter Predict Intracranial Pressure in Traumatic Brain Injury Patients.

[This retracts the article DOI: 10.1155/2022/9808334.].

Exploring fullerene-based superlattices self-assembled via giant molecules

Fullerene, as a novel building block of functional materials, possesses a wide range of intriguing properties, some of which are closely related to hierarchical structures. Advancing the methodology for manipulating fullerene hierarchical structures could facilitate developments of novel fullerene-based materials with desired properties. In the present work, we report our exploration of a series of fullerene-based unconventional spherical packing nanostructures, including Frank-Kasper (FK) A15 and σ phases as well as dodecagonal quasicrystalline (DDQC) phase in unary self-assembly systems of fullerene-based giant molecules. Also, in giant molecule binary blends, alloy-type spherical phases with high volume asymmetries such as FK Laves C14 (MgZn2) and C15 (MgCu2) phases and quasi-FK AlB2 phase can also be found. These observations showcase the feasibility of fabricating a wide range of fullerene-based superlattices through self-assembly of specifically designed giant molecules. Superlattice engineering offers a promising avenue for constructing specific structures and functions in order to achieve desired properties, in particular, for developing innovative fullerene-based materials.

Drivers of resource allocation for breeding under variable environments in a bet hedger.

The evolutionary theory of life histories predicts that there is a trade-off between survival and reproduction: since adult survival in long-lived organisms is high, then breeding investment is more variable and more dependent on conditions (e.g. food availability and individual experience). Clutch features influence fitness prospects, but how a bet hedger builds its clutch in temporally varying environments is quite unknown. Using 27-year data on 2847 clutches of known-age breeders, we analyse how Audouin's gulls (Larus audouinii), a species showing a combination of conservative and adaptive bet-hedging breeding strategies, can allocate energy by laying clutches and eggs of different sizes. Results show that both food availability and age influenced clutch size and total egg volume in a clutch. Interestingly, we found an interaction between food and age on egg parameters: total volume in two-egg clutches, laid mostly by younger breeders, did not significantly change with food availability and the quadratic pattern in clutch size over the range of ages was less marked as long as food conditions became harsher. With increased food, females invested more by building larger first eggs, whereas they were more conservative on second and third eggs. Furthermore, asymmetries in egg volume within three-egg clutches increased with food availability for old females. Egg size profiles of two-egg clutches suggest that gulls should exhibit progressive reduction of the size of the third egg before shifting to a two-egg clutch size. Food availability influenced all parameters studied, whereas age affected the amount of energy allocated for producing eggs (their size and number) but not the way of allocating those energies (i.e. asymmetries within the clutch). Despite the range of factors affecting the clutch, results suggest that females can allocate the amount of resources in a clutch optimally to increase their fitness under variable environments via bet-hedging.

Neuroanatomical correlates of cognitive impairment following basal ganglia-thalamic post-hemorrhagic stroke: Uncovering network-wide alterations in hemispheric gray matter asymmetry

Cognitive impairment and recovery are central issues in hemorrhagic stroke. This study aimed to investigate whether post-hemorrhagic stroke cognitive impairment (PhSCI) is associated with cortical gray matter (GM) loss and hemispheric asymmetry changes and whether these changes could predict improvements in cognitive function during the recovery. Nineteen patients with PhSCI, comprising 10 with basal ganglia hemorrhage and 9 with thalamic hemorrhage, were recruited. Among them, 9 completed a course of repetitive transcranial magnetic stimulation (rTMS). Additionally, 19 demographically and comorbidity-matched healthy controls were also included. Structural brain MRI and cognitive assessments were performed. Voxel-wise GM volume and hemispheric asymmetry were analyzed. The PhSCI patients exhibited bilateral, yet asymmetric, GM losses in the hippocampus, fusiform, lateral temporal, prefrontal, somatomotor, and inferior parietal regions. The analysis of GM asymmetry revealed that patients showed rightward GM in the lateral temporal, somatomotor, and inferior parietal regions. Among the 9 PhSCI patients who completed rTMS, there was a marginal trend of regional GM increase and leftward GM, and these changes were in parallel with the improvements in cognitive tests. Further lesion connectivity and metanalytic mapping identified two interconnected systems linked to the lesions, which were anchored in the default mode, somatomotor, and salience/cognitive control networks and in the cognitive domains of memory, language, decision-making, and executive function. In conclusion, PhSCI patients exhibited network-wide cortical GM losses, distal to subcortical hemorrhagic lesions, and hemisphere asymmetry changes. These changes appear to predict rTMS-related cognitive improvements, suggesting that even subcortical focal lesions can lead to alterations in distal cortical neuroanatomical architecture. Our preliminary findings provide new insights into the neuroanatomical basis of PhSCI.

Differences in complications and asymmetry in patients who did not receive a balancing procedure in two-stage and direct-to-implant breast reconstruction

Background Implant-based immediate breast reconstruction surgery with nipple-sparing mastectomy has recently been favored by patients. However, in patients who do not wish to undergo balancing procedures, it is difficult to select the appropriate implant size, making it challenging to achieve a symmetrical breast shape. Therefore, this study investigated the differences in breast asymmetry and other complications in patients who underwent a two-stage procedure or direct-to-implant (DTI) breast reconstruction to determine whether the two-stage procedure can produce more favorable outcomes.Methods The participants of this study were patients who underwent immediate two-stage breast reconstruction or DTI breast reconstruction from May 2018 to April 2022, did not receive postoperative radiotherapy, and did not wish to undergo any balancing procedures. An acellular dermal matrix was used for breast reconstruction in all patients, and a single reconstructive surgeon performed all the operations. Statistical significance was set at P<0.05.Results No significant differences in complications were found between the patients who underwent DTI breast reconstruction and those who underwent two-stage breast reconstruction. In the two-stage breast reconstruction group, breast volume asymmetry was observed in 18.4% (seven patients), which was significantly lower than the percentage of 44.7% (17 patients) observed in the DTI group.Conclusions Breast asymmetry was observed in a significant proportion of the patients in both groups. However, because breast volume asymmetry was more common in the DTI group than in the two-stage breast reconstruction group, two-stage breast reconstruction may be a favorable method for patients who do not wish to undergo balancing procedures.

Morphological variability in the inner ear of mice with osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is known to cause hearing loss in ~60% of the affected human population. While OI-related pathologies have been studied in the middle ear, the development of cochlear pathologies is less well understood. In this study, we examine OI-related pathologies of the cochlea in a mouse model of OI to (1) document variation between OI and unaffected mice, and (2) assess the intrusion of the otic capsule onto the cochlea by analyzing differences in duct volumes. Juvenile and adult OIM C57BL/6mice were compared to unaffected wildtype (WT) mice using three-dimensional models of the cochlea generated from high resolution micro-CT scans. Two-tailed Mann-Whitney U tests were then used to investigate duct volume differences both within and between the OI and WT samples. Areas of higher ossification were observed at the cochlear base in the OI sample. OI mice also had significant intraindividual differences in duct volume between right and left ears (4%-15%), an effect not observed in WT mice. WT and OI duct volumes showed a large degree of overlap, although the OIM volumes were more variable. Our findings indicate that OIM mice are likely to exhibit more asymmetry and variation in cochlear volume despite minor differences in sample cochlear volumes, possibly due to bony capsule intrusion. This suggests a potential mechanism of hearing loss, and a high potential for cochlear and otic capsule alteration in OIM mice.

Poetry and Existence: The Kingfishers of Adam Zagajewski and Gerard Manley Hopkins

The article presents an interpretation of Adam Zagajewski’s poem “The Kingfisher” from the 2014 volume Asymmetry in the context of Gerard Manley Hopkins’s [“As kingfishers catch fire, dragonflies draw flame”], whose initial words, cited in English, were used as the motto. The article reviews the motif of the kingfisher in poetry and culture. The possible readings of the poem also relate to the symbolism of colours and fire, through which its ontological and metapoetic senses are revealed.

Quantifying Muscle Size Asymmetry in Adolescent Idiopathic Scoliosis Using Three-dimensional Magnetic Resonance Imaging.

This is a case-control study of prospectively collected data. To quantify paraspinal muscle size asymmetry in adolescent idiopathic scoliosis (AIS) and determine if this asymmetry is (i) greater than observed in adolescent controls with symmetrical spines; and (ii) positively associated with skeletal maturity using Risser grade, scoliosis severity using the Cobb angle, and chronological age in years. AIS is a three-dimensional deformity of the spine which occurs in 2.5% to 3.7% of the Australian population. There is some evidence of asymmetry in paraspinal muscle activation and morphology in AIS. Asymmetric paraspinal muscle forces may facilitate asymmetric vertebral growth during adolescence. An asymmetry index [Ln(concave/convex volume)] of deep and superficial paraspinal muscle volumes, at the level of the major curve apex (Thoracic 8-9 th vertebral level) and lower-end vertebrae ( LEV , Thoracic 10-12 th vertebral level), was determined from three-dimensional Magnetic Resonance Imaging of 25 adolescents with AIS (all right thoracic curves), and 22 healthy controls (convex=left); all female, 10 to 16 years. Asymmetry index of deep paraspinal muscle volumes was greater in AIS (0.16±0.20) than healthy spine controls (-0.06±0.13) at the level of the apex ( P <0.01, linear mixed-effects analysis) but not LEV ( P >0.05). Asymmetry index was positively correlated with Risser grade ( r =0.50, P <0.05) and scoliosis Cobb angle ( r =0.45, P <0.05), but not age ( r =0.34, P >0.05). There was no difference in the asymmetry index of superficial paraspinal muscle volumes between AIS and controls ( P >0.05). The asymmetry of deep apical paraspinal muscle volume in AIS at the scoliosis apex is greater than that observed at equivalent vertebral levels in controls and may play a role in the pathogenesis of AIS.

Maxillary sinus volume and facial asymmetry after unilateral zygomaticomaxillary complex fracture reduction with 2, 3, and 4 fixation points: CBCT-based investigation

PurposeThis study aimed to assess the maxillary sinus volume (MSV), Chronic Sinusitis incidence, and asymmetry of the zygomaticomaxillary complex (ZMC) following ZMC fracture surgery with various numbers of fixation points. Materials and methodsIn a prospective non-randomized cohort, 50 adults with unilateral ZMC fractures who treated by open reduction and internal fixation (ORIF) between November 2019 and October 2021 were assigned to accomplish this study. They distributed into three groups as per fixation points (2, 3, or 4 Points). Preoperative (T1), Immediate postoperative (T2), and follow-up (T3) cone beam computed topography were analyzed using the Mimics software. The main measures were MSV and asymmetry indexes (ASI) of six paired bilateral anatomical landmarks (Orbital, Suprajugal, Jugale, Zygon, Maxillozygion 1, and Maxillozygion 2). ResultsMSV decreased significantly on the affected sides postoperatively in 2P and 3P groups, both in T2 and T3. Further, the T2-T3 comparisons showed a significant MSV change (p = 0.001). ASI reduced considerably to clinically tolerated levels (<3 mm) on landmarks near the fixation sites postoperatively. The ASI on the Zygon and Maxillozygion 1 landmarks showed significant changes among the three groups in both T2 and T3. Interestingly, only five cases had reported postoperative sinusitis symptoms. ConclusionsAlthough the MSV was changed among the different fixation point groups, the incidence of chronic sinusitis was uncommon. Bilateral asymmetry affected by number and position of the fixation points, fixation with 4 points provide more symmetry.

Definitions of Abnormal Breast Size and Asymmetry: A Cohort Study of 400 Women.

Macromastia, micromastia and breast asymmetry have an impact on health and quality of life. However, there is scarce information addressing breast size and asymmetry frequency distribution in reference populations. The current study aims to identify factors that influence breast size and symmetry and classifies abnormal breast sizes and breast asymmetries in an adult German population. Breast base dimensions, breast volume, symmetry, and other breast anthropometric parameters of 400 German female patients were determined in a retrospective review of the MRI archives at our institution. Professional medical MRI-segmentation software was used for volume measurement. A total of 400 Patients were retrospectively enrolled. The patients had a mean age of 50 ± 12years (min: 24; max: 82), mean BMI of 25.0 ± 5.0 (min: 14.7, max: 45.6), and a mean total breast volume of 976ml (right: 973ml, min: 64, max: 4777; left: 979ml, min: 55, max: 4670). The strongest correlation of breast volume was observed with BMI (r = 0.834, p < 0.001), followed by breast base width (r = 0.799, p < 0.001). Smaller breasts have higher breast volume asymmetry ratios (r = - 0.124, p < 0.014). For a BMI between 18.5 and 24.9kg/m2, micromastia is defined by breast volumes below 250ml (5th percentile) and macromastia by volumes above 1250ml (95th percentile). Abnormal breast volume asymmetry (< 5th and > 95th percentile) is equivalent to an absolute difference of approximately 25% relative to the smallest side (bidirectional asymmetry ratio 5th percentile - 19%; 95th percentile 26%). This study provides normative data of German women, as well as selected size-for-BMI percentiles and asymmetry ratio percentiles. The normative data may help to establish transparent and objective coverage criteria for health insurances. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Postprocessing of MRIs Using FreeSurfer in Epilepsy Surgery Patients Provides an Excellent Imaging Marker of Hippocampal Sclerosis but Fails to Separate Subtypes

Objective. Histopathological examinations will diminish as minimally invasive epilepsy surgery increasingly replaces open surgery. The objective of this study was to test if visual and computer-aided quantitative analyses of presurgical high-quality 3 Tesla MRIs complying with the International League Against Epilepsy (ILAE) Neuroimaging Task Force recommendations can inform on histopathological diagnosis. Methods. Ninety-two patients from Copenhagen and Oslo University Hospitals fulfilled patient-, imaging-, and histopathological inclusion criteria: 69 patients were diagnosed with hippocampal sclerosis (HS) ILAE type 1 or 2, and 23 patients had normal appearing hippocampi or other histopathology than HS (no-HS). MRIs from 52 healthy controls (HC) were included. Image processing was performed in FreeSurfer v.6.0 with the built-in cross-sectional hippocampal subfield segmentation tool and multimodal MRI input. Volume outputs were used to calculate volume asymmetry ratios (VARs) for whole hippocampus (WH) and subfields. Results. HS patients had significantly larger WH VARs compared to no-HS patients and HC, with a sensitivity = 0.93 and specificity = 1.0 for histopathological HS diagnosis. Visual MRI assessment yielded a sensitivity = 0.90 and specificity = 0.96 for histopathological HS diagnosis. CA1 and CA4 VARs and the number of seizure-free patients were not significantly different in HS ILAE type 1 compared to type 2 patients. Significance. FreeSurfer analyses of presurgical MRIs are excellent at separating patients histopathologically diagnosed with HS from patients with other pathology or normal appearing hippocampi. Using the FreeSurfer hippocampal subfield segmentation tool did not allow for separating HS ILAE subtypes.

Calvarial Vault Remodeling Technique for Lambdoid Craniosynostosis.

Premature fusion of the lambdoid suture is the most uncommon single-suture synostosis. It presents with a classic "windswept" appearance, a trapezoid-shaped head, and significant skull asymmetry notable for an ipsilateral mastoid bulge and contralateral frontal bossing. Because of the rarity of lambdoid synostosis, little is known about optimal techniques for its treatment. In particular, the proximity of the lambdoid suture to critical intracranial structures such as the superior sagittal and transverse sinuses represents a potential for significant intraoperative bleeding. Prior work has shown that parietal asymmetry persists after repair in these cases. In this article, the authors present a technique for the treatment of unilateral lambdoid craniosynostosis along with two representative cases. This calvarial vault remodeling technique requires the removal of both ipsilateral and contralateral parietal bones. These are moved across hemispheres and reinset on opposite sides to help correct the parietal asymmetry. Obliquely orientated barrel stave osteotomies are performed to provide a safe mechanism for correction of occipital flattening. The authors' early results show improvement in correction of volume asymmetry 1 year postoperatively relative to patients treated with prior calvarial vault remodeling techniques. The authors believe the technique presented here corrects the windswept appearance in patients with lambdoid craniosynostosis and also reduces the potential for complications. Further work will be necessary to confirm this technique's long-term efficacy in a larger cohort.

Analysis of brain volume asymmetry and clinical application in patients with temporal lobe epilepsy with hippocampal sclerosis based on automatic brain segmentation

Objective: To analyze whole brain structural volume asymmetry in temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) using automated brain segmentation technology, and to investigate the application value of this technology in the diagnosis of TLE-HS and the performance in determining the location the lateralization of epileptogenic focus. Methods: Twenty-eight patients with TLE-HS were enrolled in the First Affiliated Hospital of Zhengzhou University from April 2019 to October 2020, including 13 females and 15 males, aged ranged from 18 to 63 (30±12) years, and these patients were divided two group according to the epilepsy lateralization, left TLE-HS(LTLE-HS) group (n=11), right TLE-HS(RTLE-HS) group (n=17) and 28 normal controls [aged ranged from 18 to 49 (29±10) years]. All of these subjects underwent three-dimensional T1 weighted image (3D T1WI). The differences of brain structure and volumes in LTLE-HS, RTLE-HS and normal controls group were retrospectively analyzed, and Pearson's correlation coefficient was used to evaluate the left and right volume correlations, and effect size was used for evaluating the differences in left and right volume averages. The asymmetry index (AI) of the left and right lateral volumes in each group was also calculated and compared among the three groups. Results: Standard volumes of all structures within the brain were asymmetric in the normal controls, LTLE-HS, and RTLE-HS groups, with smaller volumes of ipsilateral hippocampus than contralateral hippocampus in both the LTLE-HS and RTLE-HS groups(0.20%±0.03% vs 0.24%±0.02%,0.21%±0.03% vs 0.25%±0.02% respectively;both P<0.001), and smaller volumes of gray and white matter of the ipsilateral temporal lobe than contralateral in the LTLE-HS group(4.41%±0.38% vs 5.01%±0.43%,1.83%±0.22 % vs 2.22%±0.14%;both P<0.001). There was a moderate to strong linear correlation (0.553<r<0. 964,all P<0.05) between left and right lateral volumes in the normal controls, LTLE-HS, and RTLE-HS groups. All three groups showed the largest effect sizes in the cingulate gyrus (The effect sizes were 3.07, 4.85 and 4.22 in control, LTLE-HS and RTLE-HS, respectively.). The AI values of the hippocampus, temporal lobe gray matter, and temporal lobe white matter were statistically different among the three groups (-1.48±8.64 vs 15.91±10.15 vs -17.59±10.00, 7.46±2.67 vs 12.67±6.67 vs 3.67±6.15, 6.53±3.71 vs 19.91±9.85 vs 1.57±8.38;all P<0.001). Conclusion: Volumetric measurements by automated brain segmentation techniques can play an important role in preoperative assessment of TLE, and the asymmetry of brain volume may be of value in determining the localization and extent of the epileptogenic focus.

The association between dental and facial symmetry in adolescents

Facial aesthetics have become one of the most important objectives of orthodontic treatment. The correction of dental arches should be performed in accordance with the face. This study explored the association between occlusal and facial asymmetries in adolescents, particularly emphasizing a Class II subdivision. Eighty-one adolescents (43 males, 38 females) with a median age of 15.9 (interquartile range, 15.17-16.33) years were enrolled. Of these patients, 30 had a Class II subdivision (right side, n= 12; left side, n= 18). Three-dimensional facial scans were analyzed using surface- and landmark-based methods. Chin asymmetry was determined using the chin volume asymmetry score. Three-dimensional intraoral scans were analyzed to assess occlusal asymmetry. The surface matching scores were 59.0% ± 11.3% for the whole face and 39.0% ± 19.2% for the chin. Chin volume was larger on the right side than on the left side in most patients (n= 51, 63%), and it was associated with a dental midline shift to the corresponding subdivision side. A correlation between dental and facial asymmetries was noted. In addition, the dental midline shifted to the left in patients with a Class II subdivision, regardless of the side, and to the right in those with a symmetrical Class II subdivision. However, several patients did not possess asymmetrical occlusal traits sufficient for statistical analysis. Dental asymmetry was weak but significantly correlated with facial asymmetry.

Sex differences in fetal intracranial volumes assessed by in utero MR imaging

BackgroundThe primary aim of the study is to test the null hypothesis that there are no statistically significant differences in intracranial volumes between male and female fetuses. Furthermore, we have studied the symmetry of the cerebral hemispheres in the cohort of low-risk fetuses.Methods200 normal fetuses between 18 and 37 gestational weeks (gw) were included in the cohort and all had in utero MR, consisting of routine and 3D-volume imaging. The surfaces of the cerebral ventricles, brain and internal table of the skull were outlined manually and volume measurements were obtained of ventricles (VV), brain parenchyma (BPV), extraaxial CSF spaces (EAV) and the total intracranial volume (TICV). The changes in those values were studied over the gestational range, along with potential gender differences and asymmetries of the cerebral hemispheres.ResultsBPV and VV increased steadily from 18 to 37 gestational weeks, and as a result TICV also increased steadily over that period. TICV and BPV increased at a statistically significantly greater rate in male relative to female fetuses after 24gw. The greater VV in male fetuses was apparent earlier, but the rate of increase was similar for male and female fetuses. There was no difference between the genders in the left and right hemispherical volumes, and they remained symmetrical over the age range measured.ConclusionsWe have described the growth of the major intracranial compartments in fetuses between 18 and 37gw. We have shown a number of statistically different features between male and female fetuses, but we have not detected any asymmetry in volumes of the fetal cerebral hemispheres.