Limited Sampling Spatial Interpolation Evaluation for 3D Radio Environment Mapping.

The increasing densification and diversification of modern and upcoming wireless networks have become an important motivation for the development of agile spectrum sharing. Radio environment maps (REMs) are a basic tool for spectrum utilisation characterisation and adaptive resource allocation, but they need to be estimated through accurate interpolation methods. This work evaluated the performance of two established algorithms for spatial three-dimensional (3D) data collected in two real-world scenarios: indoors, through a mechanical measuring system, and outdoors, through an unmanned aerial vehicle (UAV) for measurement collection. The investigation was undertaken for the complete dataset on two-dimensional (2D) planes of different altitudes and for a subset of limited samples (representing the regions of interest or RoIs), which were combined together to describe the spatial 3D environment. A minimum error of -9.5 dB was achieved for a sampling ratio of 21%. The methods' performance and the input data were analysed through the resulting Kriging error standard deviation (STD) and the STD of the distances between the measurement and the estimated points. Based on the results, several challenges for the interpolation performance and the analysis of the spatial RoIs are described. They facilitate the future development of 3D spectrum occupancy characterisation in indoor and UAV-based scenarios.

UAV-Based Volumetric Measurements toward Radio Environment Map Construction and Analysis.

Unmanned aerial vehicle (UAV)-empowered communications have gained significant attention in recent years due to the promise of agile coverage provision for a large number of various mobile nodes on the ground and in three-dimensional (3D) space. Consequently, there is a need for efficient spectrum utilization in these dense aerial networks, which is characterized through radio environment maps (REMs), the construction of which is an important research area. Nevertheless, due to the difficult collection of radio frequency (RF) data, there are limited works that are based on real-world measurement campaigns. This paper presents a novel experimental setup that includes a constellation of three UAVs, the communication signals of which are measured by a software-defined radio (SDR) mounted on a separate UAV. It follows a trajectory that defines the REM's two-dimensional (2D) area on a plane, executed at four altitudes, to extend the REM to 3D. The measurements are then processed and their features (received mean power level, average difference of the mean power, percentage of meaningful correlations) are analyzed in the temporal, spatial, and frequency domains to determine the utilization of a 20 MHz band in the 2.4 GHz spectrum, as well as their variation with altitude. This analysis provides a base for research in reducing the amount of measurements (by identifying the regions of low and of high interest) and spectrum occupancy prediction for UAV-based communication coexistence.

Surface values, volumetric measurements and radiomics of structural MRI for the diagnosis and subtyping of attention-deficit/hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) is diagnosed subjectively based on an individual's behaviour and performance. The clinical community has no objective biomarker to inform the diagnosis and subtyping of ADHD. This study aimed to explore the potential diagnostic biomarkers of ADHD among surface values, volumetric metrics and radiomic features that were extracted from structural MRI images. Public data of New York University and Peking University were downloaded from the ADHD-200 Consortium. MRI T1-weighted images were pre-processed using CAT12. We calculated surface values based on the Desikan-Killiany atlas. The volumetric metrics (mean grey matter volume and mean white matter volume) and radiomic features within each automated anatomical labelling (AAL) brain area were calculated using DPABI and IBEX, respectively. The differences among three groups of participants were tested using ANOVA or Kruskal-Wallis test depending on the normality of the data. We selected discriminative features and classified typically developing controls (TDCs) and ADHD patients as well as two ADHD subtypes using least absolute shrinkage and selection operator and support vector machine algorithms. Our results showed that the radiomics-based model outperformed the others in discriminating ADHD from TDC and classifying ADHD subtypes (area under the curve [AUC]: 0.78 and 0.94 in training test; 0.79 and 0.85 in testing set). Combining grey matter volumes, surface values and clinical factors with radiomic features can improve the performance for classifying ADHD patients and TDCs with training and testing AUCs of 0.82 and 0.83, respectively. This study demonstrates that MRI T1-weighted features, especially radiomic features, are potential diagnostic biomarkers of ADHD.

Tunnel technique with connective tissue graft versus coronally advanced flap with enamel matrix derivate for root coverage: 2-year results of an RCT using 3D digital measuring for volumetric comparison of gingival dimensions.

AIM: The aim of this randomized clinical trial was to compare clinical and volumetric outcomes of tunnel technique (TUN) with subepithelial connective tissue graft (CTG) versus coronally advanced flap (CAF) with enamel matrix derivate (EMD) 2 years after gingival recession (GR) treatment. MATERIALS AND METHODS: Twenty-three patients contributed 45 Miller class I or II GR. At baseline and follow-up examinations, study models were collected. Their three-dimensional scans allowed precise computer-assisted measurement of recession depth (REC), complete root coverage (CRC), percentage of root coverage (RC), pointwise (pTHK) and mean areal (aTHK) marginal soft tissue thickness. Clinical examination delivered probing depths (PPD) and height of keratinized tissue. RESULTS: 24 months after surgery, digitally evaluated CRC was present in 60.0% of the TUN + CTG and 0.0% of the CAF + EMD-treated sites (p < .0001), meaning a certain relapse of the gingival margin ragarding both approaches. RC amounted to 94.0% (TUN + CTG) and 57.3% (CAF + EMD), respectively (p < .0001). REC reduction (RECred) was significantly higher for TUN + CTG (1.81 ± 0.56 mm) than for CAF + EMD (0.90 ± 0.45 mm) (p < .0001). pTHK and aTHK values were significantly greater in the TUN + CTG group (1.41 ± 0.35 mm and 1.11 ± 0.26 mm) than in the CAF + EMD group (0.78 ± 0.32 mm and 0.60 ± 0.26 mm) (p < .0001). Statistical analysis detected positive correlations between THK and both RC and RECred (p < .001). CONCLUSIONS: Two years post-operatively, CTG showed better clinical and volumetric outcomes than EMD. Increased THK values were associated with improved outcomes regarding RC and RECred.

Soft-Tissue Changes After Using Collagen Matrix Seal or Collagen Sponge With Allograft in Ridge Preservation: A Randomized Controlled Volumetric Study.

The objective of this study is to assess alterations in buccal soft-tissue contour after alveolar ridge preservation (ARP) using either a collagen matrix seal (CMS) or a collagen sponge (CS) as barriers with freeze-dried bone allograft (FDBA). Participants (28 total) were randomly assigned to the CMS group or CS group (14 participants each). The same clinical steps were used in both barriers. Cast models were taken at baseline and 4 months, and both models were then optically scanned and digitally superimposed. Volumetric, surface, and distance-adjusted measurements were calculated to assess buccal soft-tissue alterations. Surface area and volume loss in the CMS group were observed to be 71.44 ± 1189.09 mm2 and 239.58 ± 231.89 mm3, respectively. The CS group showed measurements of 139.56 ± 557.92 mm2 and 337.23 ± 310.18 mm3. Mean buccal soft-tissue loss and minimum-maximum distance loss were less in the CMS group (0.88 ± 0.52 mm and 0.2-2.15 mm, respectively) as compared with the CS group (1.63 ± 1.03 mm and 0.3-3.68 mm, respectively), with no statistically significant difference between the groups (P = .2742). Both alveolar ridge preservation barriers were unable to entirely prevent soft-tissue contour changes after extraction. However, collagen matrix seal application was slightly better in minimizing the amount of soft-tissue reduction compared with the CS.

Early Brain Activity Relates to Subsequent Brain Growth in Premature Infants.

Recent experimental studies have shown that early brain activity is crucial for neuronal survival and the development of brain networks; however, it has been challenging to assess its role in the developing human brain. We employed serial quantitative magnetic resonance imaging to measure the rate of growth in circumscribed brain tissues from preterm to term age, and compared it with measures of electroencephalographic (EEG) activity during the first postnatal days by 2 different methods. EEG metrics of functional activity were computed: EEG signal peak-to-peak amplitude and the occurrence of developmentally important spontaneous activity transients (SATs). We found that an increased brain activity in the first postnatal days correlates with a faster growth of brain structures during subsequent months until term age. Total brain volume, and in particular subcortical gray matter volume, grew faster in babies with less cortical electrical quiescence and with more SAT events. The present findings are compatible with the idea that (1) early cortical network activity is important for brain growth, and that (2) objective measures may be devised to follow early human brain activity in a biologically reasoned way in future research as well as during intensive care treatment.

Tunnel technique with connective tissue graft versus coronally advanced flap with enamel matrix derivative for root coverage: a RCT using 3D digital measuring methods. Part II. Volumetric studies on healing dynamics and gingival dimensions.

AIM: The aim of this randomized clinical trial (RCT) was to compare the clinical performance of the tunnel technique with subepithelial connective tissue graft (TUN) versus a coronally advanced flap with enamel matrix derivative (CAF) in the treatment of gingival recession defects. The use of innovative 3D digital measuring methods allowed to study healing dynamics at connective tissue (CT)-grafted sites and to evaluate the influence of the thickness of the root covering soft tissues on the outcome of surgical root coverage. MATERIAL & METHODS: Twenty-four patients contributed a total of 47 Miller class I or II recessions for scientific evaluation. Precise study models collected at baseline and follow-up examinations were optically scanned and virtually superimposed for digital evaluation of clinical outcome measures including mean marginal soft tissue thickness (THK). Healing dynamics were measured in a defined region of interest at CT-grafted sites where volume differences between time points were calculated. RESULTS: At 12 months, recession reduction as well as mean root coverage were significantly better at CT-grafted sites treated in the TUN group (1.94 mm and 98.4% respectively) compared to the non-augmented sites of the CAF group (1.17 mm and 71.8% respectively) and statistical analysis revealed a positive correlation of THK (1.63 mm TUN versus 0.91 mm CAF, p < 0.0001) to both these variables. Soft tissue healing following surgical root coverage with CT-grafting was mainly accomplished after 6 months, with around two-thirds of the augmented volume being maintained after 12 months. CONCLUSIONS: The TUN resulted in thicker gingiva and better clinical outcomes compared to CAF. Increased gingival thickness was associated with better surgical outcomes in terms of recession reduction and root coverage.

Detection and measurement of artificial periapical lesions by cone-beam computed tomography.

AIM: To test the ability of periapical radiography (PA) and cone-beam computed tomography (CBCT) to determine the presence/absence of periapical lesions and examine the reliability of volumetric measurements of periapical lesions on CBCT scans. METHODOLOGY: After tooth extractions in human mandibles, bone defects were cut at the base of extraction sockets to mimic periapical bone lesions. The teeth were then returned into the extraction sockets. Sixty-three roots of anterior teeth, premolars and molars with artificial periapical lesions and 37 roots without lesions were examined with PA and CBCT. Presence/absence of periapical lesion was noted. The CBCT-based volume of each lesion (Vct) was measured using Amira software 5.4 (Visage Imaging GmbH, Berlin, Germany). A replica of each lesion was created using silicone impression material, and the volume of the replica was measured using a water displacement method, representing the physical volume of the lesion (Vp). Regression analysis was used to test the correlation between the Vp and Vct values. RESULTS: The positive and negative predictive values and accuracy for CBCT in diagnosing periapical lesions were all 1, compared with 1, 0.64 and 0.79 for PA diagnosis. Twenty-one (33%) lesions were undetected by PA. The Vp (21.5 ± 11.0 mm(3) ) and Vct (21.4 ± 11.5 mm(3) ) values of 63 lesions were highly correlated (R(2) = 96.9%, P < 0.001). CONCLUSION: Cone-beam computed tomography is more accurate than PA in diagnosing periapical lesions associated with mandibular teeth. The volumes of artificial mandibular periapical lesions were accurately measured with CBCT data.

Current use of real-time three-dimensional transthoracic echocardiography in animals.

This review includes 36 studies of transthoracic real-time three-dimensional echocardiography (RT3DE) in animals. Most of these studies concern cardiac chamber quantification of the left atrium and left ventricle, in dogs. Comparisons of RT3DE and different two-dimensional echocardiographic (2DE) methods have been reported in dogs with myxomatous mitral valve disease (MMVD), dilated cardiomyopathy, and in healthy control dogs. Comparisons of RT3DE and standard reference methods have been reported in healthy control dogs. In dogs with MMVD, volumetric RT3DE measurements of left atrium do not appear to provide superior prognostic value compared with 2DE methods using Simpson's method of discs in dogs with MMVD. The major advantages of RT3DE compared to 2DE include improvements in visualization of the complex morphology of the mitral valve, the estimation of mitral valve regurgitation, and improved visualization of complex congenital cardiac abnormalities.

Longitudinal follow-up of incidental renal calculi on computed tomography.

RATIONALE AND OBJECTIVES: Measuring small kidney stones on CT is a time-consuming task often neglected. Volumetric assessment provides a better measure of size than linear dimensions. Our objective is to analyze the growth rate and prognosis of incidental kidney stones in asymptomatic patients on CT. MATERIALS AND METHODS: This retrospective study included 4266 scans from 2030 asymptomatic patients who underwent two or more nonenhanced CT scans for colorectal screening between 2004 and 2016. The DL software identified and measured the volume, location, and attenuation of 883 stones. The corresponding scans were manually evaluated, and patients without follow-up were excluded. At each follow-up, the stones were categorized as new, growing, persistent, or resolved. Stone size (volume and diameter), attenuation, and location were correlated with the outcome and growth rates of the stones. RESULTS: The stone cohort comprised 407 scans from 189 (M: 124, F: 65, median age: 55.4 years) patients. The median number of stones per scan was 1 (IQR: [1, 2]). The median stone volume was 17.1 mm3 (IQR: [7.4, 43.6]) and the median peak attenuation was 308 HU (IQR: [204, 532]. The 189 initial scans contained 291stones; 91 (31.3%) resolved, 142 (48.8%) grew, and 58 (19.9) remained persistent at the first follow-up. At the second follow-up (for 27 patients with 2 follow-ups), 14/44 (31.8%) stones had resolved, 19/44 (43.2%) grew and 11/44 (25%) were persistent. The median growth rate of growing stones was 3.3 mm3/year, IQR: [1.4,7.4]. Size and attenuation had a moderate correlation (Spearman rho 0.53, P < .001 for volume, and 0.50 P < .001 for peak attenuation) with the growth rate. Growing and persistent stones had significantly greater maximum axial diameter (2.7 vs 2.3 mm, P =.047) and peak attenuation (300 vs 258 HU, P =.031) CONCLUSION: We report a 12.7% prevalence of incidental kidney stones in asymptomatic adults, of which about half grew during follow-up with a median growth rate of about 3.3 mm3/year.

Long-term outcome of multilayer flow modulator in aortic aneurysms.

BACKGROUND: This retrospective study investigated the efficacy of endovascular treatment with multilayer flow modulators (MFMs) for treating aortic aneurysms in high-risk patients unsuitable for conventional treatments. PATIENTS AND METHODS: Conducted from 2011 to 2019 at a single center, this retrospective observational study included 17 patients who underwent endovascular treatment with MFMs. These patients were selected based on their unsuitability for traditional surgical or endovascular procedures. The study involved meticulous pre-procedural planning, precise implantation of MFMs, and follow-up using CT angiography. The primary focus was on volumetric and flow volume changes in aneurysms, along with traditional diameter measurements. Moreover, the technical success and post-procedural complications were also registered. RESULTS: The technical success rate was 100%, and 30-day procedural complication rate was 17.6%. Post-treatment assessments revealed that 11 out of 17 patients showed a decrease in flow volume within the aneurysm sac, indicative of a favorable hemodynamic response. The median decrease in flow volume was 12 ml, with a median relative decrease of 8%. However, there was no consistent reduction in aneurysm size; most aneurysms demonstrated a median increase in volume for 46 ml and median increase in diameter for 18 mm. CONCLUSIONS: While MFMs offer a potential alternative for high-risk aortic aneurysm patients, their effectiveness in preventing aneurysm expansion is limited. The results suggest that MFMs can provide a stable hemodynamic environment but do not reliably reduce aneurysm size. This underscores the need for ongoing vigilance and long-term monitoring in patients treated with this technology.

Assessment of the Efficiency of Measuring Foot and Ankle Edema with a 3D Portable Scanner.

Background: To prospectively evaluate the reliability of a portable optical scanner compared to the water displacement technique for volumetric measurements of the foot and ankle and to compare the acquisition time associated with these two methods. Methods: Foot volume was measured in 29 healthy volunteers (58 feet, 24 females and 5 males) by a 3D scanner (UPOD-S 3D Laser Full-Foot Scanner®) and by water displacement volumetry. Measurements were performed on both feet, up to a height of 10 cm above the ground. The acquisition time for each method was evaluated. The Kolmogorov-Smirnov test, Lin's Concordance Correlation Coefficient, and a Student's t-test were performed. Results: Mean foot volume was 869.7 +/- 165.1 cm3 (3D scanner) versus 867.9 +/- 155.4 cm3 (water-displacement volumetry) (p < 10-5). The concordance of measurements was 0.93, indicative of a high correlation between the two techniques. Volumes were 47.8 cm3 lower when using the 3D scanner versus water volumetry. After statistically correcting this underestimation, the concordance was improved (0.98, residual bias = -0.03 +/- 35.1 cm3). The mean examination time was 4.2 +/- 1.7 min (3D optical scanner) versus 11.1 +/- 2.9 min (water volumeter) (p < 10-4). Conclusions: Ankle/foot volumetric measurements performed using this portable 3D scanner are reliable and fast and can be used in clinical practice and research.

MRI Response Assessment in Glioblastoma Patients Treated with Dendritic-Cell-Based Immunotherapy.

Introduction: In this post hoc analysis we compared various response-assessment criteria in newly diagnosed glioblastoma (GB) patients treated with tumor lysate-charged autologous dendritic cells (Audencel) and determined the differences in prediction of progression-free survival (PFS) and overall survival (OS). Methods: 76 patients enrolled in a multicenter phase II trial receiving standard of care (SOC, n = 40) or SOC + Audencel vaccine (n = 36) were included. MRI scans were evaluated using MacDonald, RANO, Vol-RANO, mRANO, Vol-mRANO and iRANO criteria. Tumor volumes (T1 contrast-enhancing as well as T2/FLAIR volumes) were calculated by semiautomatic segmentation. The Kruskal-Wallis-test was used to detect differences in PFS among the assessment criteria; for correlation analysis the Spearman test was used. Results: There was a significant difference in median PFS between mRANO (8.6 months) and Vol-mRANO (8.6 months) compared to MacDonald (4.0 months), RANO (4.2 months) and Vol-RANO (5.4 months). For the vaccination arm, median PFS by iRANO was 6.2 months. There was no difference in PFS between SOC and SOC + Audencel. The best correlation between PFS/OS was detected for mRANO (r = 0.65) and Vol-mRANO (r = 0.69, each p < 0.001). A total of 16/76 patients developed a pure T2/FLAIR progressing disease, and 4/36 patients treated with Audencel developed pseudoprogression. Conclusion: When comparing different response-assessment criteria in GB patients treated with dendritic cell-based immunotherapy, the best correlation between PFS and OS was observed for mRANO and Vol-mRANO. Interestingly, iRANO was not superior for predicting OS in patients treated with Audencel.

Echocardiographic reference intervals for right ventricular indices, including 3-dimensional volume and 2-dimensional strain measurements in healthy dogs.

BACKGROUND: There is currently a lack of reference intervals (RIs) for the novel measures like 3-dimensional (3D) echocardiography or speckle-tracking strain for assessment of right ventricular (RV) structure and function. OBJECTIVES: To generate RIs and to determine the influence of age, heart rate, and body weight (BW) on various RV function indices using a dedicated RV software for 3D RV end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), global and free wall RV longitudinal strain (RVLS), end-diastolic area (RVEDA), end-systolic area (RVESA), fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), and tissue Doppler imaging (TVI)-derived systolic myocardial velocity of the lateral tricuspid annulus (S'). ANIMALS: Healthy adult client-owned dogs (n = 211) of various breeds and ages. METHODS: Prospective study. Reference intervals were estimated as statistical prediction intervals using allometric scaling for BW-dependent variables. Right-sided (upper limit) or left-sided (lower limit) 95% RIs were calculated for every variable. Inter- and intraobserver variability was determined. RESULTS: Most variables showed clinically acceptable repeatability with coefficient of variation less than 10. Upper or respectively lower RI after allometric scaling to normalize for different BWs were: EDVn ≤ 2.5 mL/kg0.942 , ESVn ≤ 1.2 mL/kg0.962 , TAPSEn ≥ 4.5 mm0.285 , RVEDAn ≤ 1.4 cm2 /kg0.665 , RVESAn ≤ 0.8 cm2 /kg0.695 , and TVI S'n ≥ 5.6 cm/s/kg0.186 . The calculated limits for indices without allometric normalization were: EF > 42.1%, FAC > 30.0%, free wall RVLS < -20.8%, and global RVLS < -18.3%. CONCLUSIONS: Echocardiographic RIs for RV structure and function are provided.

Left Ventricle Wall Motion Analysis with Real-Time MRI Feature Tracking in Heart Failure Patients: A Pilot Study.

Volumetric measurements with cardiac magnetic resonance imaging (MRI) are effective for evaluating heart failure (HF) with systolic dysfunction that typically induces a lower ejection fraction (EF) than normal (<50%) while they are not sensitive to diastolic dysfunction in HF patients with preserved EF (≥50%). This work is to investigate whether HF evaluation with cardiac MRI can be improved with real-time MRI feature tracking. In a cardiac MRI study, we recruited 16 healthy volunteers, 8 HF patients with EF < 50% and 10 HF patients with preserved EF. Using real-time feature tracking, a cardiac MRI index, torsion correlation, was calculated which evaluated the correlation of torsional and radial wall motion in the left ventricle (LV) over a series of sequential cardiac cycles. The HF patients with preserved EF and the healthy volunteers presented significant difference in torsion correlation (one-way ANOVA, p < 0.001). In the scatter plots of EF against torsion correlation, the HF patients with EF < 50%, the HF patients with preserved EF and the healthy volunteers were well differentiated, indicating that real-time MRI feature tracking provided LV function assessment complementary to volumetric measurements. This study demonstrated the potential of cardiac MRI for evaluating both systolic and diastolic dysfunction in HF patients.

Echocardiographic reference intervals for volumetric measurements of the left ventricle using the Simpson's method of discs in 1331 dogs.

BACKGROUND: Echocardiographic measurements play an important role in detecting cardiac enlargement and assessing cardiac function. In human cardiology, M-mode measurements have been widely replaced by volumetric measurements of the left ventricle (LV) using Simpson's method of disc (SMOD). In veterinary cardiology, more large-scale studies are necessary to generate reference intervals (RIs) for SMOD LV volume measurements. OBJECTIVE: To generate body size independent RIs for LV volume measurements in dogs. ANIMALS: Healthy adult dogs (n = 1331) of variable size and somatotype. METHODS: Prospective study. The SMOD was measured from the right parasternal long axis and the left apical 4-chamber view in clinically healthy dogs. The SMOD measurements were normalized to various allometric scales (kg, kg2/3 , or kg1/3 ). RIs for LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV) using SMOD were estimated as prediction intervals of both a linear and an additive regression model. Additionally, after normalization to body weight, 95% RIs were determined using nonparametric methods with 2.5 and 97.5 percentiles serving as the lower and upper limits. Separate analyses were performed for 120 sighthound breeds and 1211 other breeds. RESULTS: Echocardiographic LV volumes correlated best with weight in kilograms. The additive model proved to be more flexible and accurate than the other 2 methods to generate RIs. Separate RIs for sighthound and all other breeds are provided. CONCLUSIONS AND CLINICAL IMPORTANCE: Body size and breed-independent RIs for LV volume measurements using SMOD were generated prospectively from a large and diverse population of dogs and are available for clinical use.

Volumetric measures of the paralyzed vocal fold using computerized tomography; its clinical implication.

OBJECTIVE: To report the volumetric measures of the paralyzed vocal fold in patients undergoing injection laryngoplasty. MATERIAL AND METHOD: All the medical records of patients with unilateral vocal fold paralysis who had high resolution computerized tomography scan of the neck and chest prior to injection laryngoplasty between October 2015 and May 2018 were included. Volumetric evaluation of the vocal folds was performed by measuring the vocal fold height using coronal images and the vocal fold length and width using axial images. RESULTS: A total of 21 patients divided into 13 males and 8 females were identified. The mean age was 56.66 ± 20.94 years. The mean volume of the paralyzed vocal fold was significantly smaller than that of the non-paralyzed vocal fold (p < .05). Similarly, the mean length and height of the paralyzed vocal folds were smaller than those of the non-paralyzed vocal folds (p < .05). CONCLUSION: Volumetric measurements of the paralyzed vocal fold in comparison to the normal vocal fold in a group of 21 patients with unilateral vocal fold paralysis shows the presence of significant difference between the normal and affected site, and the presence of large inter-subject variation. Information on the volume difference between the two vocal folds may be used to better estimate the amount that needs to be injected in medialization procedures.

Four-year Outcome of Nonsurgical Root Canal Retreatment Using Cone-beam Computed Tomography: A Prospective Cohort Study.

INTRODUCTION: The purpose of this prospective study was to investigate the 4-year outcome and prognostic factors of nonsurgical root canal retreatment determined by measuring the volumetric change of periapical radiolucencies on cone-beam computed tomographic (CBCT) scans. METHODS: Ninety-seven endodontically treated teeth from 80 patients diagnosed as apical periodontitis and indicated for root canal retreatment were included. Retreatment was performed by 7 endodontic specialists using a standardized treatment protocol. The teeth were reexamined clinically and radiographically 48-67 months after retreatment. The volume of preoperative and postoperative periapical radiolucencies on CBCT images was independently measured by 2 examiners. Radiographic outcome is presented in 4 categories: absence, reduction, enlargement, or unchanged. Reduction or enlargement was determined when the volumetric change of radiolucency was 20% or more. Multivariate logistic regression was performed for predictor analysis. RESULTS: Sixty-two teeth (63.9%) from 50 patients returned for follow-up. Fifty-eight teeth were included in the prognostic analysis, all of which were symptom free. The 4 remaining teeth that had been extracted because of fracture were excluded. The total volume of periapical radiolucencies at 4 years postoperatively decreased by 94.6% compared with that preoperatively (P < .001), with an average reduction of 83.4% (95% confidence interval, 69.2%-97.5%). The periapical radiolucencies were determined as absence in 44 teeth (75.9%), reduction in 10 teeth (17.2%), unchanged in 1 tooth (1.7%), and enlargement in 3 teeth (5.2%). Tooth type was identified as an outcome predictor (P < .05). CONCLUSIONS: The 4-year outcome of endodontic retreatment is predictable, with a significant volumetric reduction in periapical radiolucencies.

Incorporation of quantitative MRI in a model to predict temporal lobe epilepsy surgery outcome.

Quantitative volumetric brain MRI measurement is important in research applications, but translating it into patient care is challenging. We explore the incorporation of clinical automated quantitative MRI measurements in statistical models predicting outcomes of surgery for temporal lobe epilepsy. Four hundred and thirty-five patients with drug-resistant epilepsy who underwent temporal lobe surgery at Cleveland Clinic, Mayo Clinic and University of Campinas were studied. We obtained volumetric measurements from the pre-operative T1-weighted MRI using NeuroQuant, a Food and Drug Administration approved software package. We created sets of statistical models to predict the probability of complete seizure-freedom or an Engel score of I at the last follow-up. The cohort was randomly split into training and testing sets, with a ratio of 7:3. Model discrimination was assessed using the concordance statistic (C-statistic). We compared four sets of models and selected the one with the highest concordance index. Volumetric differences in pre-surgical MRI located predominantly in the frontocentral and temporal regions were associated with poorer outcomes. The addition of volumetric measurements to the model with clinical variables alone increased the model's C-statistic from 0.58 to 0.70 (right-sided surgery) and from 0.61 to 0.66 (left-sided surgery) for complete seizure freedom and from 0.62 to 0.67 (right-sided surgery) and from 0.68 to 0.73 (left-sided surgery) for an Engel I outcome score. 57% of patients with extra-temporal abnormalities were seizure-free at last follow-up, compared to 68% of those with no such abnormalities (P-value = 0.02). Adding quantitative MRI data increases the performance of a model developed to predict post-operative seizure outcomes. The distribution of the regions of interest included in the final model supports the notion that focal epilepsies are network disorders and that subtle cortical volume loss outside the surgical site influences seizure outcome.

Preservation of Alveolar Ridge using Graft Material after Tooth Extraction: A Clinical Trial.

BACKGROUND: The alveolar process is a tooth-dependent structure, and hence, removal of teeth results in the alteration of alveolar process. To alter bone remodeling after dental extraction, various techniques have been put forward for ridge preservation. AIM: The aim of this study is to evaluate and compare the changes of hard and soft tissues in postextraction socket after the application of bone graft material. MATERIALS AND METHODS: Healthy patients of sample size of 40 were selected who underwent the extraction of anterior tooth irrespective of the arch, from premolar of one side to another, with the exception of incisors in mandible. Twenty patients were randomly selected as the control group and other 20 as the experimental group using an allograft bone material, i.e., beta-tricalcium phosphate to fill the socket. Cone-beam computed tomography (CBCT) was done as baseline preoperative and postoperative at 14 weeks after the extraction. CBCTs data help in recording linear and volumetric measurements which was performed by calibrated examiners to record all the measurements. After measurements, digital planning of dental implants was performed. RESULTS: Forty participants were selected, in which 20 patients each were as the experimental and control groups. No significant difference was found at basal line at any of the cases. At follow-up of 14 weeks, statistical significance was seen in buccal and lingual plate height in the experimental group, and no significant difference was seen in the control group.(P = 0.023). CONCLUSIONS: This study clearly points out that an alveolar ridge preservation technique provides therapeutic benefit by limiting bone resorption in comparison to extraction alone.