scholarly journals The 3D Tele Motion Tracking for the Orthodontic Facial Analysis

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Stefano Mummolo ◽  
Alessandro Nota ◽  
Enrico Marchetti ◽  
Giuseppe Padricelli ◽  
Giuseppe Marzo
Keyword(s):  
Motion Tracking ◽  
Dynamic Testing ◽  
Three Dimensional ◽  
Cephalometric Analysis ◽  
Facial Analysis ◽  
The Face ◽  
The Mean ◽  
2D And 3D ◽  
Very High ◽  
Posterior Anterior

Aim. This study aimed to evaluate the reliability of 3D-TMT, previously used only for dynamic testing, in a static cephalometric evaluation. Material and Method. A group of 40 patients (20 males and 20 females; mean age 14.2±1.2 years; 12–18 years old) was included in the study. The measurements obtained by the 3D-TMT cephalometric analysis with a conventional frontal cephalometric analysis were compared for each subject. Nine passive markers reflectors were positioned on the face skin for the detection of the profile of the patient. Through the acquisition of these points, corresponding plans for three-dimensional posterior-anterior cephalometric analysis were found. Results. The cephalometric results carried out with 3D-TMT and with traditional posterior-anterior cephalometric analysis showed the 3D-TMT system values are slightly higher than the values measured on radiographs but statistically significant; nevertheless their correlation is very high. Conclusion. The recorded values obtained using the 3D-TMT analysis were correlated to cephalometric analysis, with small but statistically significant differences. The Dahlberg errors resulted to be always lower than the mean difference between the 2D and 3D measurements. A clinician should use, during the clinical monitoring of a patient, always the same method, to avoid comparing different millimeter magnitudes.

Performing Distance Measurements in Curved Facial Regions: A Comparison between Three-Dimensional Surface Scanning and Ultrasound Imaging

2021 ◽  
Author(s):  
Michael Alfertshofer ◽  
Konstantin Frank ◽  
Dmitry V. Melnikov ◽  
Nicholas Möllhoff ◽  
Robert H. Gotkin ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Dimensional Accuracy ◽  
Ultrasound Measurement ◽  
Surface Scanning ◽  
Distance Measurements ◽  
Surgical Performance ◽  
Facial Region ◽  
3D Surface ◽  
The Face ◽  
The Mean

AbstractFacial flap surgery depends strongly on thorough preoperative planning and precise surgical performance. To increase the dimensional accuracy of transferred facial flaps, the methods of ultrasound and three-dimensional (3D) surface scanning offer great possibilities. This study aimed to compare different methods of measuring distances in the facial region and where they can be used reliably. The study population consisted of 20 volunteers (10 males and 10 females) with a mean age of 26.7 ± 7.2 years and a mean body mass index of 22.6 ± 2.2 kg/m2. Adhesives with a standardized length of 20 mm were measured in various facial regions through ultrasound and 3D surface scans, and the results were compared. Regardless of the facial region, the mean length measured through ultrasound was 18.83 mm, whereas it was 19.89 mm for 3D surface scans, with both p < 0.0001. Thus, the mean difference was 1.17 mm for ultrasound measurements and 0.11 mm for 3D surface scans. Curved facial regions show a great complexity when it comes to measuring distances due to the concavity and convexity of the face. Distance measurements through 3D surface scanning showed more accurate distances than the ultrasound measurement. Especially in “complex” facial regions (e.g., glabella region and labiomental sulcus), the 3D surface scanning showed clear advantages.

scholarly journals Evaluation of three-dimensional acromiohumeral distance in the standing position and comparison with its conventional measuring methods

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Yuki Yoshida ◽  
Noboru Matsumura ◽  
Yoshitake Yamada ◽  
Minoru Yamada ◽  
Yoichi Yokoyama ◽  
...  
Keyword(s):  
Supine Position ◽  
Humeral Head ◽  
Three Dimensional ◽  
Standing Position ◽  
Ct Scanner ◽  
Mean Values ◽  
Measuring Methods ◽  
The Mean ◽  
Acromiohumeral Distance ◽  
2D And 3D

Abstract Background Narrowing of the acromiohumeral distance (AHD) implies a rotator cuff tear. However, conventional AHD measurements using two-dimensional (2D) imaging or with the patient in the supine position might differ from that while standing during daily activity. This study aimed to evaluate the three-dimensional (3D) actual distance between the acromion and humeral head in the standing position and compare the AHD values with those obtained using conventional measuring methods. Methods Computed tomography (CT) images of 166 shoulders from 83 healthy volunteers (31 male and 52 female; mean age 40.1 ± 5.8 years; age range, 30–49 years) were prospectively acquired in the supine and standing positions using conventional and upright CT scanners, respectively. The minimum distance between the acromion and humeral head on the 3D surface models was considered as the 3D AHD. We measured the 2D AHD on anteroposterior digitally reconstructed radiographs. The AHD values were compared between the supine and standing positions and between the 2D and 3D measurements. Results The mean values of 2D AHD were 8.8 ± 1.3 mm (range, 5.9–15.4 mm) in the standing position and 8.1 ± 1.2 mm (range, 5.3–14.3 mm) in the supine position. The mean values of 3D AHD were 7.3 ± 1.4 mm (range, 4.7–14.0 mm) in the standing position and 6.6 ± 1.2 mm (range, 4.4–13.7 mm) in the supine position. The values of 3D AHD were significantly lower than those of 2D AHDs in both the standing and supine positions (P < 0.001). The values of 2D and 3D AHDs were significantly lower in the supine position than in the standing position (P < 0.001). Conclusions This study evaluated the 3D AHD of normal shoulders in the standing position using an upright CT scanner. The present results indicated that assessments in the supine position can underestimate the value of the AHD compared with those made in the standing position and that assessments using 2D analysis can overestimate the value.

scholarly journals The Reliability of a Three-Dimensional Photo System- (3dMDface-) Based Evaluation of the Face in Cleft Lip Infants

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Rebecca Ort ◽  
Philipp Metzler ◽  
Astrid L. Kruse ◽  
Felix Matthews ◽  
Wolfgang Zemann ◽  
...  
Keyword(s):  
Data Acquisition ◽  
Cleft Lip ◽  
Three Dimensional ◽  
Accurate Data ◽  
3D Images ◽  
Facial Landmarks ◽  
Mean Error ◽  
Clinical Investigations ◽  
The Face ◽  
The Mean

Ample data exists about the high precision of three-dimensional (3D) scanning devices and their data acquisition of the facial surface. However, a question remains regarding which facial landmarks are reliable if identified in 3D images taken under clinical circumstances. Sources of error to be addressed could be technical, user dependent, or patient respectively anatomy related. Based on clinical 3D photos taken with the 3dMDface system, the intra observer repeatability of 27 facial landmarks in six cleft lip (CL) infants and one non-CL infant was evaluated based on a total of over 1,100 measurements. Data acquisition was sometimes challenging but successful in all patients. The mean error was 0.86 mm, with a range of 0.39 mm (Exocanthion) to 2.21 mm (soft gonion). Typically, landmarks provided a small mean error but still showed quite a high variance in measurements, for example, exocanthion from 0.04 mm to 0.93 mm. Vice versa, relatively imprecise landmarks still provide accurate data regarding specific spatial planes. One must be aware of the fact that the degree of precision is dependent on landmarks and spatial planes in question. In clinical investigations, the degree of reliability for landmarks evaluated should be taken into account. Additional reliability can be achieved via multiple measuring.

REDUCED TRANSFER MATRIX APPROACH FOR ISING MODEL

2011 ◽  
Vol 25 (21) ◽  
pp. 2895-2903 ◽  
Author(s):  
TUNCER KAYA ◽  
MURAT ARIK
Keyword(s):  
Transfer Matrix ◽  
Coupling Strength ◽  
Spontaneous Magnetization ◽  
Mean Field Theory ◽  
Mean Field ◽  
Three Dimensional ◽  
Critical Coupling ◽  
Transfer Matrix Approach ◽  
The Mean ◽  
2D And 3D

In this work, we present a simple approximate transfer matrix method for 2D and 3D Ising ferromagnet to calculate spontaneous magnetization of the system. The critical coupling strength Kc of 2D and 3D Ising models in reduced transfer matrix approximation is obtained quite accurately by simple improvements over the mean field theory. The important physical effect we include is the some of the fluctuations effects of the systems directly with help of this method. We predict from the spontaneous magnetization curve that the critical coupling strength Kc=J/kBT = 0.401 and 0.245 for two-dimensional (2D) and three-dimensional (3D) systems, respectively.

scholarly journals Evaluation of three-dimensional acromiohumeral distance in the standing position and comparison with its conventional measuring methods

2020 ◽  
Author(s):  
Yuki Yoshida ◽  
Noboru Matsumura ◽  
Yoshitake Yamada ◽  
Minoru Yamada ◽  
Yoichi Yokoyama ◽  
...  
Keyword(s):  
Supine Position ◽  
Humeral Head ◽  
Three Dimensional ◽  
Standing Position ◽  
Ct Scanner ◽  
Mean Values ◽  
Measuring Methods ◽  
The Mean ◽  
Acromiohumeral Distance ◽  
2D And 3D

Abstract Background: Narrowing of the acromiohumeral distance (AHD) implies a rotator cuff tear. However, conventional AHD measurements using two-dimensional (2D) imaging or with the patient in the supine position might differ from that while standing during daily activity. This study aimed to evaluate the three-dimensional (3D) actual distance between the acromion and humeral head in the standing position and compare the AHD values with those obtained using conventional measuring methods.Methods: Computed tomography (CT) images of 166 shoulders from 83 healthy volunteers (31 male and 52 female; mean age 40.1 ± 5.8 years; age range, 30–49 years) were prospectively acquired in the supine and standing positions using conventional and upright CT scanners, respectively. The minimum distance between the acromion and humeral head on the 3D surface models was considered as the 3D AHD. We measured the 2D AHD on anteroposterior digitally reconstructed radiographs. The AHD values were compared between the supine and standing positions and between the 2D and 3D measurements.Results: The mean values of 2D AHD were 8.8 ± 1.3 mm (range, 5.9–15.4 mm) in the standing position and 8.1 ± 1.2 mm (range, 5.3–14.3 mm) in the supine position. The mean values of 3D AHD were 7.3 ± 1.4 mm (range, 4.7–14.0 mm) in the standing position and 6.6 ± 1.2 mm (range, 4.4–13.7 mm) in the supine position. The values of 3D AHD were significantly lower than those of 2D AHDs in both the standing and supine positions (P < 0.001). The values of 2D and 3D AHDs were significantly lower in the supine position than in the standing position (P < 0.001). Conclusions: This study evaluated the 3D AHD of normal shoulders in the standing position using an upright CT scanner. The present results indicated that assessments in the supine position can underestimate the value of the AHD compared with those made in the standing position and that assessments using 2D analysis can overestimate the value.

scholarly journals Facelift Part I: History, Anatomy, and Clinical Assessment

2019 ◽  
Vol 40 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Ahmed M Hashem ◽  
Rafael A Couto ◽  
Eliana F R Duraes ◽  
Çagri Çakmakoğlu ◽  
Marco Swanson ◽  
...  
Keyword(s):  
Clinical Judgment ◽  
Three Dimensional ◽  
Treatment Strategies ◽  
Surgical Anatomy ◽  
Facial Appearance ◽  
Facial Aging ◽  
Facial Analysis ◽  
Safe Navigation ◽  
The Face ◽  
Neck Rejuvenation

AbstractIn this article, the authors aim to thoroughly describe the critical surgical anatomy of the facial layers, the retaining ligamentous attachments of the face, and the complex three-dimensional course of the pertinent nerves. This is supplemented with clarifying anatomic dissections and artwork figures whenever possible to enable easy, sound, and safe navigation during surgery. The historic milestones that led the evolution of cervicofacial rejuvenation to the art we know today are summarized at the beginning, and the pearls of the relevant facial analysis that permit accurate clinical judgment and hence individualized treatment strategies are highlighted at the end. The facelift operation remains the cornerstone of face and neck rejuvenation. Despite the emergence of numerous less invasive modalities, surgery continues to be the most powerful and more durable technique to modify facial appearance. All other procedures designed to ameliorate facial aging are either built around or serve as adjuncts to this formidable craft.

Clinical dosimetry optimization in spinal metastases

2009 ◽  
Vol 8 (1) ◽  
pp. 35-40
Author(s):  
P. Pedrosa ◽  
C. Lucena ◽  
I.J. Sainz
Keyword(s):  
Organs At Risk ◽  
Three Dimensional ◽  
Spinal Metastases ◽  
Target Volume ◽  
The Body ◽  
High Dose ◽  
Prescription Dose ◽  
The Mean ◽  
Posterior Anterior ◽  
Anterior Posterior

AbstractIntroduction: Radiotherapy is commonly used to treat spinal metastases. The aim of this study was to compare conventional dosimetry (posterior–anterior fields) with an optimized three-dimensional conformal plan (using oblique fields).Material and Methods: Fifteen patients were selected, and split into three groups of five based on tumour localization: cervical, dorsal and lumbar. Reference planning comprised of two fields: anterior–posterior. The planning target volume (PTV) was covered with 90% of the prescribed doses, minimizing anterior field weight and not exceeding 120%. The alternative consisted of three fields: two oblique posterior fields with wedge and anterior field. The PTV was covered with 95% of the prescription dose, minimizing the anterior field weight with 107% of overdose as a limit. The patient received 8 Gy in one fraction; retreatment with an additional fraction was feasible, safe and effective if persistent or recurrent bone pain was present. Five fractions of 4 Gy were used for cervical cases. To consider the future patients toxicity we evaluated the mean dose, V90 and V70 parameters in each plan.Results: Dosimetric parameters of organs at risk were not significantly different from one trial to another. The optimized plan followed ICRU criteria, reaching PTV coverage of 95–107% range of the prescription dose. In the conventional plan, high dose had to be accepted to obtain 90% of coverage in the target.Conclusions: In contrast with the anterior–posterior configuration, oblique fields improve dose conformity and limit high dose all of the body except the spinal cord.

Impact of CT-based planning and bladder volume changes on the dosimetry of vaginal vault brachytherapy

2021 ◽  
pp. 1-7
Author(s):  
Jeyaanth Venkatasai ◽  
Jebakarunya Ramireddy ◽  
Arvind Sathyamurthy ◽  
Henry Finlay Godson ◽  
Reka Karuppusami ◽  
...  
Keyword(s):  
Clinical Target Volume ◽  
Organs At Risk ◽  
Three Dimensional ◽  
Target Volume ◽  
Bladder Distension ◽  
Full Bladder ◽  
The Mean ◽  
2D And 3D ◽  
Planning Ct ◽  
Empty Bladder

Abstract Aim: To compare dose to target and organs at risk (OARs) in conventional plan (2D) versus computed tomography (CT)-based three-dimensional (3D) plan in vaginal cuff brachytherapy (VBT) and to compare the effect of bladder distension on target and OARs dosimetry. Materials and methods: Post-hysterectomy patients with an indication for VBT were included in the study. All patients underwent planning CT scans with a full bladder and an empty bladder protocol. For each CT, two plans were generated—one library-based 2D plan and another CT-based 3D plan. Dosimetric parameters were recorded for clinical target volume (CTV) and OARs. Results: A total of 92 observations were made from data collected from 46 patients. Difference between CTV dose in terms of 2D and 3D plans were not statistically significant for CTV (p = 0·11). Significant reduction in D0·1cc, D1cc and D2cc dose parameters were observed in bladder, rectum, sigmoid and bowel doses with the 3D plan (p < 0·001). Bladder distension showed a 20% reduction in dose for bowel (p < 0·001). Bladder distension also showed a 6·12% (p = 0·047) increase in D2cc, but there was a significant reduction in the mean dose to the bladder. Conclusion: Our study demonstrates the dosimetric benefits with 3D CT-based planning for VBT over 2D-based conventional planning and benefit of bladder distension in the reduction of bowel dose without compromising dose to the target volume.

scholarly journals Comparisons of acromiohumeral distance measurements between two- and three-dimensional imaging and between the supine and standing positions

2020 ◽  
Author(s):  
Yuki Yoshida ◽  
Noboru Matsumura ◽  
Yoshitake Yamada ◽  
Minoru Yamada ◽  
Yoichi Yokoyama ◽  
...  
Keyword(s):  
Supine Position ◽  
Humeral Head ◽  
Three Dimensional ◽  
Standing Position ◽  
Two Dimensional ◽  
Subacromial Space ◽  
Mean Values ◽  
The Mean ◽  
Acromiohumeral Distance ◽  
2D And 3D

Abstract Background Narrowing of the acromiohumeral distance (AHD) implies a rotator cuff tear. However, AHD measurements on two-dimensional (2D) imaging or with the patient in the supine position might differ from that while standing during daily activity. This study aimed to accurately measure the distance between the acromion and the humeral head on three-dimensional (3D) imaging acquired in the standing position and to compare this with AHD measurements made on images acquired in the supine position and on 2D images. Methods Computed tomography (CT) images of 166 shoulders from 83 healthy volunteers (31 male and 52 female; mean age 40.1 ± 5.8 years; age range, 30–49 years) were prospectively acquired in the supine and standing positions using conventional and upright CT scanners, respectively. AHD was calculated as the minimum distance between the acromion and the humeral head on the 3D surface models. Two-dimensional AHD was measured on anteroposterior digitally reconstructed radiographs images. The AHD values were compared between the supine and standing positions and between the 2D and 3D measurements. Results The mean values of 2D AHD were 8.8 ± 1.3 mm (range, 5.9–15.4 mm) in the standing position and 8.1 ± 1.2 mm (range, 5.3–14.3 mm) in the supine position. The mean values of 3D AHD were 7.3 ± 1.4 mm (range, 4.7–14.0 mm) in the standing position and 6.6 ± 1.2 mm (range, 4.4–13.7 mm) in the supine position. The values of 3D AHD were significantly lower than those of 2D AHDs in both the standing and supine positions (P < 0.001). The values of 2D and 3D AHDs were significantly lower in the supine position than in the standing position (P < 0.001). Conclusions The present results indicated that assessments in the supine position can underestimate the value of the AHD compared with those made in the standing position and that assessments using 2D analysis can overestimate the value. It is necessary to understand that the anatomical distance of the subacromial space changes with images and gravity.

Interobserver Agreement in the Study of 2D and 3D Sonographic Criteria for Adenomyosis

2017 ◽  
Vol 9 (3) ◽  
pp. 211-215 ◽  
Author(s):  
José M. Puente ◽  
Juan L. Alcazar ◽  
Pilar Martinez-Ten ◽  
Carmina Bermejo ◽  
María T. Troncoso ◽  
...  
Keyword(s):  
Interobserver Agreement ◽  
Transvaginal Ultrasound ◽  
Three Dimensional ◽  
Kappa Index ◽  
Junctional Zone ◽  
Experienced Observer ◽  
3D Sonography ◽  
2D And 3D ◽  
Very High ◽  
Good Agreement

Objective To study the degree of interobserver agreement for already known two-dimensional (2D) and three-dimensional (3D) sonography criteria of adenomyosis. Methods Fifty cases (25 adenomyosis cases, 25 non-adenomyosis cases) were studied by four expert observers and a less-experienced researcher. Each sonographic adenomyosis criterion was separately studied. Interobserver agreement was analysed by the kappa index with 95% confidence interval (CI). Results The degree of agreement about diagnosing adenomyosis was high or very high in all pair-wise comparisons (kappa values of 0.58–0–92). The agreement on identifying intra-myometrial cysts (kappa values of 0.46–0.79) and evaluating the junctional zone (JZ) by 3D-transvaginal ultrasound (3D-TVS) (kappa index of 0.46–0.88) was good. The agreements reached when evaluating the other criteria varied, but good agreement was generally reached. Conclusions Both the 2D-TVS and 3D-TVS criteria employed in diagnosing adenomyosis were reproducible parameters in adenomyosis diagnostics. The results were reproducible, even by a less experienced observer.

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