Evaluation of angles of the tracheobronchial tree with the 3-dimensional reconstruction method: a morphometric and radiologic study / Evaluación de los ángulos del árbol traqueobronquial con el método de reconstrucción tridimensional: un estudio morfométrico y radiológico

SUMMARY: The objective of the current research is to assess the branching angles of the tracheobronchial tree and the correlation between these angles and the lung volume using the 3-dimensional reconstruction method. Thorax CT (computed tomography) images of 150 individuals, who were over 18 years of age and did not have any pathology on CT, were obtained retrospectively. A 3-dimensional reconstruction of the trachea, bronchi, and lungs was carried out. External and internal angles between the trachea and main bronchi, between the main bronchi and lobar bronchi, and between the lobar bronchi were measured. The volume measurement of the right and left lungs was performed. The individuals included in the study were grouped by sex and age (20-40 years, 41-61 years, and 62-87 years). The left subcarinal angle (LSA), total subcarinal angle (TSA), and left interbronchial angle (LIA) were found to be greater in the 62-87 age group. Both the external angle (LULB-LMBE) and the internal angle (LULB- LMBI) between the left upper lobar bronchus and the left main bronchus were observed to be greater in males. In males, a statistically significant negative moderate correlation was identified between the right lung volume and the right subcarinal angle (RSA). In females, a statistically significant positive moderate correlation was revealed between the external (RULB-IBE) and internal angles (RULB-IBI) between the right upper lobar bronchus and the intermediate bronchus, and the right lung volume. In the literature review we performed, we did not find any studies investigating the correlation between the branching angles of the tracheobronchial tree and the lung volume using the 3-dimensional reconstruction method. Therefore, we are of the opinion that our study will contribute to the literature.

El objetivo de la investigación fue evaluar los ángulos de ramificación del árbol traqueobronquial y la correlación entre estos ángulos y el volumen pulmonar utilizando el método de reconstrucción tridimensional. Se obtuvieron retrospectivamente imágenes de tomografía computarizada de tórax de 150 individuos mayores de 18 años sin patología. Se realizó una reconstrucción tridimensional de la tráquea, los bronquios y los pulmones. Se midieron los ángulos externo e interno entre la tráquea y los bronquios principales, entre los bronquios principales y los bronquios lobares, y entre los bronquios lobares. Se realizó la medición del volumen de los pulmones derecho e izquierdo. Los individuos incluidos en el estudio fueron agrupados por sexo y edad (20-40 años, 41-61 años y 62-87 años). Se encontró que el ángulo subcarinal izquierdo, el ángulo subcarinal total y el ángulo interbronquial izquierdo eran mayores en el grupo de edad de 62 a 87 años. Tanto el ángulo externo (LULB-LMBE) como el ángulo interno (LULB-LMBI) entre el bronquio lobular superior izquierdo y el bronquio principal izquierdo era mayor en los hombres. En los hombres, se identificó una correlación moderada negativa estadísticamente significativa entre el volumen pulmonar derecho y el ángulo subcarinal derecho. En mujeres, se reveló una correlación positiva moderada estadísticamente significativa entre los ángulos externos (RULB-IBE) e internos (RULB-IBI) entre el bronquio lobar superior derecho y el bronquio intermedio, y el volumen pulmonar derecho. En la revisión bibliográfica que realizamos, no encontramos ningún estudio que analizara la correlación entre los ángulos de ramificación del árbol traqueobronquial y el volumen pulmonar utilizando el método de reconstrucción tridimensional. Por lo tanto, consideramos que nuestro estudio contribuirá a la literatura especializada del tema.

Morphometric examination of the trachea and bronchi in follow-up computed tomography scans of COVID-19 patients / Examen morfométrico de la tráquea y los bronquios en tomografías computarizadas de seguimiento de pacientes con COVID-19

SUMMARY: The purpose of this study is to evaluate changes in the trachea and bronchi using 3-dimensional reconstruction images obtained from the initial and follow-up computed tomography (CT) scans of COVID-19 patients. A hundred COVID-19 patients over the age of 18 were included in our study. CT images were transferred to Mimics software, and a 3-dimensional reconstruction of the trachea and bronchi was performed. The initial and follow-up CT images of COVID-19 patients were graded as none (grade 0), mild (grade 1), moderate (grade 2), and severe (grade 3) according to the total lung severity score. The patients were divided into progression and regression groups according to the grade increase/decrease between the initial and follow-up CTs. Moreover, the patients were divided into groups as 0-2 weeks, 2-4 weeks, 4-12 weeks, and over 12 weeks according to the duration between the initial and follow-up CTs. The mean cross-sectional area, circumference, and diameter measurements of the right upper lobar bronchus, intermediate bronchus, middle lobar bronchus, and left lower lobar bronchus decreased in the follow-up CTs of the progression group. This decrease was not found to be statistically significant. In the follow-up CTs of the regression group, the left upper lobar bronchus and left lower lobar bronchus measurements increased but not statistically significant. Upon comparing the onset of the disease and the follow-up period, statistically significant changes did not occur in the trachea, main bronchus, and lobar bronchus of COVID-19 patients.

El propósito de este estudio fue evaluar los cambios en la tráquea y los bronquios utilizando imágenes de reconstrucción tridimensionales obtenidas de las tomografías computarizadas (TC) iniciales y de seguimiento de pacientes con COVID-19. En nuestro estudio se incluyeron 100 pacientes con COVID-19 mayores de 18 años. Las imágenes de TC se transfirieron al software Mimics y se realizó una reconstrucción tridimensional de la tráquea y los bronquios. Las imágenes de TC iniciales y de seguimiento de los pacientes con COVID-19 se calificaron como ninguna (grado 0), leve (grado 1), moderada (grado 2) y grave (grado 3) según la puntuación total de gravedad pulmonar. Los pacientes se dividieron en grupos de progresión y regresión según el aumento/disminución del grado entre las TC iniciales y de seguimiento. Además, los pacientes se dividieron en grupos de 0 a 2 semanas, de 2 a 4 semanas, de 4 a 12 semanas y de más de 12 semanas según la duración entre la TC inicial y la de seguimiento. Las mediciones medias del área transversal, la circunferencia y el diámetro del bronquio lobar superior derecho, el bronquio intermedio, el bronquio lobar medio y el bronquio lobar inferior izquierdo disminuyeron en las TC de seguimiento del grupo de progresión. No se encontró que esta disminución fuera estadísticamente significativa. En las TC de seguimiento del grupo de regresión, las mediciones del bronquio lobar superior izquierdo y del bronquio lobar inferior izquierdo aumentaron pero no fueron estadísticamente significativas. Al comparar el inicio de la enfermedad y el período de seguimiento, no ocurrieron cambios estadísticamente significativos en la tráquea, el bronquio principal y el bronquio lobar de los pacientes con COVID-19.

MDCT with three-dimensional fusion images in the preoperative evaluation of pancreaticoduodenectomy / 中华肝胆外科杂志

Objective To study the role of MDCT with 3D fusion images in the preoperative evaluation of pancreaticoduodenectomy.Methods 37 patients who underwent pancreaticoduodenectomy from March 2016 to May 2018 in the Affiliated Wuxi No.2 People's Hospital of Nanjing Medical University were included in this retrospective study.All patients underwent a dual-phase enhanced MDCT before operation.The volume data of enhanced MDCT were transmitted to a dedicated CT post-processing workstation.The 3D images,including the tumor,pancreas,portal vein system,arterial system,pancreatic and biliary tract,were reformatted respectively before the fusion imaging.Two reviewers analyzed the tumor location and its spatial relations with the pancreaticobiliary system,peripancreatic vessels and vascular variations by means of zooming,rotating,splitting and transparent displaying on fusion images.Then,the assessed items were compared to the surgical and pathological findings.Results The 3D fusion images of 37 patients in this study depicted the tumor,pancreas,peripancreatic vessels and pancreatic and biliary tract clearly.Compared with the intraoperative and pathological findings,the accuracy of both tumor detection and localization with the 3D fusion images was 100％.To compare the intraoperative findings,visualization and variation detection of the celiac,splenic,common hepatic,gastroduodenal,hepatic,and superior mesenteric arteries,and the superior mesenteric and portal veins were all 100％.Visualizations of the anterior superior pancreaticoduodenal artery (ASPDA),posterior superior pancreaticoduodenal artery (PSPDA),inferior pancreaticoduodenal artery (IPA) and dorsal pancreatic artery (DPA) were 85.7％,82.8％,72.2％ and 75.8％,respectively.Conclusion The MDCT 3D fusion imaging technology allowed one stop preoperative assessment of pancreaticoduodenectomy,especially in clearly outlining the tumor location and its spatial relations with the surrounding surgical anatomies before surgery.

An Evaluation of Validity of Measurements using Digital Caliper and Three-dimensional Virtual Dental Models / 대한해부학회지

The measurement of tooth and the space analysis of dental study models are essential for precise diagnosis and treatment plan for orthodontic or prosthodontic cases. Traditionally, these have been done on study models with instruments, such as a divider or a caliper. At present, three-dimensional (3-D) virtual dental models are available for clinicians, supplemented by dedicated software for performing needed measurements on them. For example, Autoscan system for dental application(TM) (ASDA; INUS technology INC, Korea) is one of these systems using a non-contact 3- D scanner. The accuracy of this system has been tested and validated by the Korea Testing Laboratory. However, the outline of dental models is not simple and has many undercuts. Therefore, we sought to evaluate the accuracy of measuring models using digital calipers or ASDA to compare these two techniques. From each ten study models, 10 duplicated stone and 10 virtual models were generated. Virtual models were scanned from duplicated model because of revival of clinical situation. Then, central incisors, canines, first molars, arch (intercanine and intermolar) width of original model were measured by a digital caliper, and the same items of virtual models were measured by software. All measurements were performed twice by two experienced observers. Data were statistically analyzed by 2-way Analysis of Variance (2-way ANOVA, SPSS Ver. 11.5). The results from this study have demonstrated that virtual model is highly valid and reliable for measuring both tooth size and arch width. Although some values of virtual model are higher or lower than original dental model, the significance value is still higher than 0.97. A digital caliper seems to be a more precise instrument to perform a scientific work, ASDA's accuracy is clinically acceptable. Furthermore, considering its present advantages and future possible applications, the examined or equivalent 3-D virtual models may become the standard for clinical use.

3-Dimensional Reconstruction of CT Image

According to the rapid development of computer technology, 3-dimensional reconstruction of CT scan data is becoming one of most up-to-dated diagnostic imaging techniques. This technique is helpful for determining the morphology of complex human structures, surgical plannings and for training aids. The authors developed the 3-dimensional reconstruction software which can be running at the personal computer. The various phases in the generation of 3-D reconstruction are described and clinical application is demonstrated by examples.