COVID-19 Computed tomography patterns in renal replacement therapy patients / Padrões de tomografia computadorizada da COVID-19 em pacientes em terapia renal substitutiva

ABSTRACT Introduction: Lung diseases are common in patients with end stage kidney disease (ESKD), making differential diagnosis with COVID-19 a challenge. This study describes pulmonary chest tomography (CT) findings in hospitalized ESKD patients on renal replacement therapy (RRT) with clinical suspicion of COVID-19. Methods: ESKD individuals referred to emergency department older than 18 years with clinical suspicion of COVID-19 were recruited. Epidemiological baseline clinical information was extracted from electronic health records. Pulmonary CT was classified as typical, indeterminate, atypical or negative. We then compared the CT findings of positive and negative COVID-19 patients. Results: We recruited 109 patients (62.3% COVID-19-positive) between March and December 2020, mean age 60 ± 12.5 years, 43% female. The most common etiology of ESKD was diabetes. Median time on dialysis was 36 months, interquartile range = 12-84. The most common pulmonary lesion on CT was ground glass opacities. Typical CT pattern was more common in COVID-19 patients (40 (61%) vs 0 (0%) in non-COVID-19 patients, p < 0.001). Sensitivity was 60.61% (40/66) and specificity was 100% (40/40). Positive predictive value and negative predictive value were 100% and 62.3%, respectively. Atypical CT pattern was more frequent in COVID-19-negative patients (9 (14%) vs 24 (56%) in COVID-19-positive, p < 0.001), while the indeterminate pattern was similar in both groups (13 (20%) vs 6 (14%), p = 0.606), and negative pattern was more common in COVID-19-negative patients (4 (6%) vs 12 (28%), p = 0.002). Conclusions: In hospitalized ESKD patients on RRT, atypical chest CT pattern cannot adequately rule out the diagnosis of COVID-19.

RESUMO Introdução: Doenças pulmonares são comuns em pacientes com doença renal em estágio terminal (DRET), dificultando o diagnóstico diferencial com COVID-19. Este estudo descreve achados de tomografia computadorizada de tórax (TC) em pacientes com DRET em terapia renal substitutiva (TRS) hospitalizados com suspeita de COVID-19. Métodos: Indivíduos maiores de 18 anos com DRET, encaminhados ao pronto-socorro com suspeita de COVID-19 foram incluídos. Dados clínicos e epidemiológicos foram extraídos de registros eletrônicos de saúde. A TC foi classificada como típica, indeterminada, atípica, negativa. Comparamos achados tomográficos de pacientes com COVID-19 positivos e negativos. Resultados: Recrutamos 109 pacientes (62,3% COVID-19-positivos) entre março e dezembro de 2020, idade média de 60 ± 12,5 anos, 43% mulheres. A etiologia mais comum da DRET foi diabetes. Tempo médio em diálise foi 36 meses, intervalo interquartil = 12-84. A lesão pulmonar mais comum foi opacidades em vidro fosco. O padrão típico de TC foi mais comum em pacientes com COVID-19 (40 (61%) vs. 0 (0%) em pacientes sem COVID-19, p < 0,001). Sensibilidade 60,61% (40/66), especificidade 100% (40/40). Valores preditivos positivos e negativos foram 100% e 62,3%, respectivamente. Padrão atípico de TC foi mais frequente em pacientes COVID-19-negativos (9 (14%) vs. 24 (56%) em COVID-19-positivos, p < 0,001), enquanto padrão indeterminado foi semelhante em ambos os grupos (13 (20%) vs. 6 (14%), p = 0,606), e padrão negativo foi mais comum em pacientes COVID-19-negativos (4 (6%) vs. 12 (28%), p = 0,002). Conclusões: Em pacientes com DRET em TRS hospitalizados, um padrão atípico de TC de tórax não pode excluir adequadamente o diagnóstico de COVID-19.

Incidence of contrast-associated acute kidney injury: a prospective cohort / Incidência de lesão renal aguda associada ao contraste: uma coorte prospectiva

ABSTRACT Introduction: Contrast-associated acute kidney injury (CA-AKI) is a deterioration of kidney function that occurs after the administration of a iodinated contrast medium (ICM). Most studies that defined this phenomenon used older ICMs that were more prone of causing CA-AKI. In the past decade, several articles questioned the true incidence of CA-AKI. However, there is still a paucity of a data about the safety of newer ICM. Objective: To assess the incidence of CA-AKI in hospitalized patients that were exposed to computed tomography (CT) with and without ICM. Methods: Prospective cohort study with 1003 patients who underwent CT in a tertiary hospital from December 2020 through March 2021. All inpatients aged > 18 years who had a CT scan during this period were screened for the study. CA-AKI was defined as a relative increase of serum creatinine of ≥ 50% from baseline or an absolute increase of ≥ 0.3 mg/dL within 18 to 48 hours after the CT. Chi-squared test, Kruskal-Wallis test, and linear regression model with restricted cubic splines were used for statistical analyses. Results: The incidence of CA-AKI was 10.1% in the ICM-exposed group and 12.4% in the control group when using the absolute increase criterion. The creatinine variation from baseline was not significantly different between groups. After adjusting for baseline factors, contrast use did not correlate with worse renal function. Conclusion: The rate of CA-AKI is very low, if present at all, with newer ICMs, and excessive caution regarding contrast use is probably unwarranted.

RESUMO Introdução: Lesão renal aguda associada ao contraste (LRA-AC) é uma deterioração da função renal que ocorre após a administração de meio de contraste iodado (MCI). A maioria dos estudos que definiram esse fenômeno utilizaram MCI mais antigos, mais propensos a causar LRA-AC. Na última década, diversos artigos questionaram a verdadeira incidência de LRA-AC. Entretanto, ainda há escassez de dados sobre a segurança dos MCI mais novos. Objetivo: Avaliar a incidência de LRA-AC em pacientes hospitalizados expostos à tomografia computadorizada (TC) com e sem MCI. Métodos: Estudo de coorte prospectivo com 1.003 pacientes submetidos a TC em hospital terciário, de dezembro/2020 a março/2021. Todos os pacientes internados com idade ≥ 18 anos que realizaram TC nesse período foram selecionados. A LRA-AC foi definida como aumento relativo de creatinina sérica de ≥ 50% em relação ao valor basal ou aumento absoluto de ≥ 0,3 mg/dL dentro de 18 a 48 horas após a TC. Utilizamos o teste qui-quadrado, teste de Kruskal-Wallis e modelo de regressão linear com splines cúbicos restritos para análises estatísticas. Resultados: A incidência de LRA-AC foi 10,1% no grupo exposto ao MCI e 12,4% no grupo controle ao usar o critério de aumento absoluto. A variação da creatinina em relação ao valor basal não foi significativamente diferente entre os grupos. Após ajuste para fatores basais, o uso de contraste não se correlacionou com pior função renal. Conclusão: A taxa de LRA-AC é muito baixa, caso exista, com MCIs mais novos, e a cautela excessiva quanto ao uso de contraste provavelmente não se justifica.

Herramientas para el tamizaje de aneurisma de aorta abdominal / Tools for abdominal aortic aneurysm screening

Introducción. El aneurisma de la aorta abdominal (AAA) es la dilatación de la aorta abdominal mayor de 1,5 veces el diámetro esperado. Su prevalencia es variable, con tasas reportadas de hasta el 12,5 %. Se considera como causa de muerte de más de 10.000 personas al año en los Estados Unidos. El objetivo de esta revisión de la literatura fue describir los factores de riesgo y las herramientas de tamizaje de AAA. Métodos. Se realizó una búsqueda de la literatura utilizando dos ecuaciones en bases de datos electrónicas, empleando términos seleccionados de "Medical Subject Heading" (MeSH) y "Descriptores en Ciencias de la Salud" (DeCS). Se evaluó la calidad de los estudios con la herramienta STROBE (Strengthening the Reporting of Observational Studies in Epidemiology). Resultados. Se recolectaron 40 artículos y a partir de ellos se construyó el texto de revisión, identificando en estos, los factores de riesgo asociados al desarrollo de AAA, tales como sexo masculino, tabaquismo, hipertensión arterial, antecedente familiar y obesidad, entre otros. La diabetes mellitus parece actuar como factor protector. Dentro de los instrumentos de tamizaje, el ultrasonido abdominal es uno de los más usados. Conclusión. El AAA es una patología multifactorial. En la actualidad la ultrasonografía de aorta es el método de elección para el tamizaje, permitiendo la detección precoz. El tamizaje de AAA con métodos no invasivos, como el ultrasonido, es útil sobre todo en zonas con prevalencia alta de la patología y en pacientes con determinados factores de riesgo.

Introduction. Abdominal aortic aneurysm (AAA) is a dilation of the abdominal aorta greater than 1.5 times the expected diameter. Its prevalence is variable, with reported rates of up to 12.5%. It is considered the cause of death of more than 10,000 people a year in the United States. The objective of this literature review was to describe risk factors and screening tools for AAA. Methods. A literature search was conducted using two equations in electronic databases, using terms selected from "Medical Subject Heading" (MeSH) and "Descriptors in Health Sciences" (DeCS). The quality of the studies was evaluated with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) tool. Results. Forty articles were collected and from them the review text was constructed, identifying the risk factors associated with the development of AAA, such as male sex, smoking, high blood pressure, family history and obesity, among others. Diabetes mellitus seems to act as a protective factor. Among the screening instruments, abdominal ultrasound is one of the most used. Conclusion. AAA is a multifactorial pathology. Currently, aortic ultrasonography is the method of choice for screening, allowing early detection. Screening for AAA with non-invasive methods, such as ultrasound, is useful especially in areas with a high prevalence of this pathology and in patients with certain risk factors.

Microcomputed-Tomographic Analysis of the Root Canal Morphology of the Mandibular First Molars in a Malaysian Subpopulation Using Two Classification Systems / Análisis por Tomografía Microcomputada de la Morfología del Conducto Radicular de los Primeros Molares Mandibulares en una Subpoblación de Malasia Utilizando dos Sistemas de Clasificación

SUMMARY: This work investigated the morphology of the root canal system of the mandibular first molar in a Malaysian subpopulation. Using micro-computed tomography with an isotropic resolution of 22 µm, 140 mandibular first molars were scanned. MIMICS software was used for segmentation, 3-D reconstruction and analysis of the acquired images. The canal configuration was described using Vertucci [supported by the supplementary configurations proposed by Sert & Bayirli (2004)] and Ahmed et al. (2027), coding systems. The chi-square test was used to assess the association between qualitative variables. By non-considering intercanal communications, Vertucci types IV (17.1%) and I (76.4%) were the most frequently reported configurations in the mesial and distal roots, respectively. Of the reported configurations, 24.3% and 4.3% were non-classifiable by Vertucci system in the mesial and distal roots, respectively. Up to 63.6% and 9.3% of the reported configurations were non- classifiable, and type I was the most frequent when considering intercanal communications (7.1% and 76.4% in the mesial and distal roots, respectively). According to Ahmed et al., system, almost half of the sample had more than four digits (47.9%), followed by the 3-digits category (20.71%). In both systems, a significant association was found between the canal configuration and the root type (p<0.001). The mandibular first molar of this Malaysian subpopulation demonstrated a wide range of root canal morphology. When compared to the Vertucci system, the system developed by Ahmed et al., successfully classified all molars configurations despite their level of complexity. The complex canal anatomy of mandibular first molars in this subpopulation warrants special attention during root canal treatment procedures.

En este trabajo se investigó la morfología del sistema de conductos radiculares del primer molar mandibular en una subpoblación de Malasia. Utilizando tomografía microcomputada con una resolución isotrópica de 22 µm, se escanearon 140 primeros molares mandibulares. Se utilizó el software MIMICS para segmentar (enmascarar), reconstruir en 3D, visualizar y analizar las imágenes adquiridas. La configuración del canal se describió utilizando Vertucci respaldado por las configuraciones complementarias propuestas por Sert & Bayirli (2004)] y Ahmed et al. (2017, 2020), sistemas de codificación. Se utilizó la prueba de chi-cuadrado para evaluar la asociación entre variables cualitativas. Sin considerar las comunicaciones intercanales, los tipos Vertucci IV (17,1%) y I (76,4%) fueron las configuraciones reportadas con mayor frecuencia en las raíces mesiales y distales, respectivamente. De las configuraciones reportadas, el 24,3 % y el 4,3 % fueron no clasificables por el sistema de Vertucci en las raíces mesial y distal, respectivamente. Hasta el 63,6 % y el 9,3 % de las configuraciones reportadas fueron no clasificables, siendo la tipo I la más frecuente al considerar las comunicaciones intercanales (7,1 % y 76,4 % en las raíces mesiales y distales, respectivamente). Según Ahmed et al. (2017, 2020) en el sistema, casi la mitad de la muestra tenía más de cuatro dígitos (47,9 %), seguido por la categoría de 3 dígitos (20,71 %). En ambos sistemas se encontró una asociación significativa entre la configuración del canal y el tipo de raíz (p<0,001). El primer molar mandibular de esta subpoblación de Malasia demostró una amplia gama morfológica del conducto radicular. En comparación con el sistema Vertucci, el sistema desarrollado por Ahmed et al. (2017, 2020) clasificaron con éxito todas las configuraciones de los molares a pesar de su nivel de complejidad. La compleja anatomía del canal de los primeros molares mandibulares en esta subpoblación merece una atención especial durante los procedimientos de tratamiento de conducto.

Tumor pseudopapilar sólido de páncreas, una neoplasia inusual / Solid Pseudopapillary Tumor of the Pancreas, an Unusual Neoplasm

Presentación del caso. Se trata de una mujer de 26 años que presentó dolor en epigastrio e hipocondrio izquierdo, con aumento del perímetro abdominal y pérdida de 5 kg de peso corporal. En el examen físico se detectó una masa de gran tamaño en el epigastrio, con bordes regulares, ligeramente dolorosa al tacto y no móvil. Los estudios de imagen revelaron una neoplasia mixta en el cuerpo y cola pancreática. Intervención terapéutica. Se practicó una esplenopancreatectomía corpo-caudal, con extirpación completa del tumor. Evolución clínica. La paciente recibió cuidados especializados y vigilancia estrecha posquirúrgica en la unidad de cuidados intensivos, sin presentar complicaciones relevantes. Tras el alta hospitalaria, la paciente refirió un buen estado general en los controles de seguimiento, que incluyeron una tomografía realizada a los 12 meses, donde no se evidenciaron restos o recidivas tumorales

Case presentation. A 26-year-old woman who presented with pain in the epigastrium and left hypochondrium, with increased abdominal perimeter and loss of 5 kg of body weight. Physical examination revealed a large mass in the epigastrium, with regular borders, slightly painful to the touch and non-mobile. Imaging studies revealed a mixed neoplasm in the pancreatic body and tail. Treatment. A corpo-caudal splenopancreatectomy was performed, with complete removal of the tumor. Outcome. The patient received specialized care and close postoperative surveillance in the intensive care unit, with no relevant complications. After hospital discharge, the patient reported a good general condition in the follow-up controls, which included a computed tomography scan performed after 12 months, where no tumor remnants or recurrences were evidenced

Uso de la tomografía corporal total en pacientes con heridas de arma de fuego y hemodinámicamente inestables: ¿Rompiendo paradigmas de atención inicial? / Whole-body computed tomography in hemodynamically unstable patients with gunshot wounds: A paradigm shift in trauma management?

Introducción. El objetivo del estudio fue analizar el impacto del uso de la tomografía corporal total en la evaluación de los pacientes con trauma penetrante por proyectil de arma de fuego y hemodinámicamente inestables atendidos en un centro de referencia de trauma. Métodos. Se realizó un estudio analítico, retrospectivo, con base en un subanálisis del registro de la Sociedad Panamericana de Trauma ­ Fundación Valle del Lili. Se incluyeron los pacientes con trauma penetrante por proyectil de arma de fuego atendidos entre 2018 y 2021. Se excluyeron los pacientes con trauma craneoencefálico severo, trauma leve y en condición in extremis. Resultados. Doscientos pacientes cumplieron los criterios de elegibilidad, 115 fueron estudiados con tomografía corporal total y se compararon con 85 controles. La mortalidad intrahospitalaria en el grupo de tomografía fue de 4/115 (3,5 %) vs 10/85 (12 %) en el grupo control. En el análisis multivariado se identificó que la tomografía no tenía asociación significativa con la mortalidad (aOR=0,46; IC95% 0,10-1,94). El grupo de tomografía tuvo una reducción relativa del 39 % en la frecuencia de cirugías mayores, con un efecto asociado en la disminución de la necesidad de cirugía (aOR=0,47; IC95% 0,22-0,98). Conclusiones. La tomografía corporal total fue empleada en el abordaje inicial de los pacientes con trauma penetrante por proyectil de arma de fuego y hemodinámicamente inestables. Su uso no se asoció con una mayor mortalidad, pero sí con una menor frecuencia de cirugías mayores.

Introduction. This study aims to assess the impact of whole-body computed tomography (WBCT) in the evaluation of patients with penetrating gunshot wounds (GSW) who are hemodynamically unstable and treated at a trauma referral center. Methods. An analytical, retrospective study was conducted based on a subanalysis of the Panamerican Trauma Society-FVL registry. Patients with GSW treated between 2018 and 2021 were included. Patients with severe cranioencephalic trauma, minor trauma, and those in extremis were excluded. Patients with and without WBCT were compared. The primary outcome was in-hospital mortality, and the secondary outcome was the frequency of major surgeries (thoracotomy, sternotomy, cervicotomy, and/or laparotomy) during initial care. Results. Two hundred eligible patients were included, with 115 undergoing WBCT and compared to 85 controls. In-hospital mortality in the WBCT group was 4/115 (3.5%) compared to 10/85 (12%) in the control group. Multivariate analysis showed that WBCT was not significantly associated to mortality (aOR: 0.46; 95% CI 0.10-1.94). The WBCT group had a relative reduction of 39% in the frequency of major surgeries, with an associated effect on reducing the need for surgery (aOR: 0.47; 95% CI 0.22-0.98). Conclusions. Whole-body computed tomography was employed in the initial management of patients with penetrating firearm projectile injuries and hemodynamic instability. The use of WBCT was not associated with mortality but rather with a reduction in the frequency of major surgery.

Effectiveness Evaluation of Low-dose Spiral Computed Tomography for Lung Cancer Screening in Minhang District of Shanghai / 中国肺癌杂志

BACKGROUND@#Low-dose spiral computed tomography (LDCT) has been recommended for lung cancer screening in high-risk populations. However, evidence from Chinese populations was limited due to the different criteria for high-risk populations and the short-term follow-up period. This study aimed to evaluate the effectiveness in Chinese adults based on the Lung Cancer Screening Program in Minhang District of Shanghai initiated in 2013.@*METHODS@#A total of 26,124 subjects aged 40 years or above were enrolled in the Lung Cancer Screening Program during the period of 2013 and 2017. Results of LDCT examination, and screen-detected cancer cases in all participants were obtained from the Reporting System of the Lung Cancer Screening Program. The newly-diagnosed cases and their vital status up to December 31, 2020 were identified through a record linkage with the Shanghai Cancer Registry and the Shanghai Vital Statistics. Standardized incidence ratio (SIR) and 95%CI were calculated using the local population at ages of 40 or above as the reference. Proportions of early-stage cancer (stage 0-I), pathological types, and 5-year observed survival rates of lung cancer cases were estimated and compared between the cases derived from the screened and non-screened populations. Cox regression models were applied to evaluate the hazard ratio (HR) and 95%CI of LDCT screening with all-cause death of the lung cancer cases.@*RESULTS@#The crude and age-standardized incidence of lung cancer in screened population were 373.3 (95%CI: 343.1-406.1) and 70.3 per 100,000 person-years, respectively, with an SIR of 1.8 (95%CI: 1.6-1.9), which was observed to decrease with following-up time. The early-stage cancer accounted for 49.4% of all lung cancer cases derived from the screened population, significantly higher than 38.4% in cases from the non-screened population during the same period (P<0.05). The proportion of lung adenocarcinoma (40.7% vs 35.9%) and 5-year survival rate (53.7% vs 41.5%) were also significantly higher in the cases from the screened population (all P<0.05). LDCT screening was associated with 30% (HR=0.7, 95%CI: 0.6-0.8) reduced all-cause deaths of the cases.@*CONCLUSIONS@#The participants of the screening program are at high-risk of lung cancer. LDCT favors the early-detection of lung cancer and improves 5-year survival of the screened cases, indicating a great potential of LDCT in reducing the disease burden of lung cancer in Chinese populations.

Cone-beam computed tomography study of root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology in high-angle Class Ⅱ open bite patients / 口腔疾病防治

Objective@#This study aimed to explore the root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology in patients with high-angle skeletal Class Ⅱ open bite, aiming to provide a reference for clinical treatment.@*. Methods@#This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. CBCT images of eighty-one untreated patients (40 anterior open bite patients and 41 normal overbite patients) with high-angle skeletal Class Ⅱ malocclusion were selected before treatment. Dolphin software was used to study the root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology, and the differences between the two groups were analyzed.@*Results@#There was no statistical significance in the root length of maxillary lateral incisor and canine between the open bite group and the normal overbite group, significant differences were found in the root length of maxillary central incisor （11.12 ± 1.37） mm、mandibular central incisor（10.15 ± 1.09）mm, mandibular lateral incisor（11.27 ± 1.15）mm and mandibular canine（12.81 ± 1.48）mm between the open bite group and the normal overbite group（P<0.05）. On the other hand, the two groups were significantly different in crown-root morphology of the maxillary central incisor (1.10° ± 3.62° vs. 4.53° ± 2.30°, P<0.01) but not in the mandibular central incisor.@*Conclusion@#The root length of the maxillary central incisor, mandibular central incisor, mandibular lateral incisor, mandibular canine in high-angle Class Ⅱ open bite patients is shorter than that in high-angle Class Ⅱ normal overbite patients, and the long axis of the crown of the maxillary central incisor in high-angle Class Ⅱ open bite patients obviously deviates toward the labial side relative to the long axis of the root. The crown-root angle is smaller, which is beneficial to torque control or adduction movement of the anterior teeth in high-angle Class Ⅱ open bite patients.

Radiomics model based on CT images for distinguishing invasive lung adenocarcinoma with micropapillary or solid structure / 中国胸心血管外科临床杂志

@#Objective    To investigate the radiomics features to distinguish invasive lung adenocarcinoma with micropapillary or solid structure. Methods    A retrospective analysis was conducted on patients who received surgeries and pathologically confirmed invasive lung adenocarcinoma in our hospital from April 2016 to August 2019. The dataset was randomly divided into a training set [including a micropapillary/solid structure positive group (positive group) and a micropapillary/solid structure negative group (negative group)] and a testing set (including a positive group and a negative group) with a ratio of 7∶3. Two radiologists drew regions of interest on preoperative high-resolution CT images to extract radiomics features. Before analysis, the intraclass correlation coefficient was used to determine the stable features, and the training set data were balanced using synthetic minority oversampling technique. After mean normalization processing, further radiomics features selection was conducted using the least absolute shrinkage and selection operator algorithm, and a 5-fold cross validation was performed. Receiver operating characteristic (ROC) curves were depicted on the training and testing sets to evaluate the diagnostic performance of the radiomics model. Results    A total of 340 patients were enrolled, including 178 males and 162 females with an average age of 60.31±6.69 years. There were 238 patients in the training set, including 120 patients in the positive group and 118 patients in the negative group. There were 102 patients in the testing set, including 52 patients in the positive group and 50 patients in the negative group. The radiomics model contained 107 features, with the final 2 features selected for the radiomics model, that is, Original_ glszm_ SizeZoneNonUniformityNormalized and Original_ shape_ SurfaceVolumeRatio. The areas under the ROC curve of the training and the testing sets of the radiomics model were 0.863 (95%CI 0.815-0.912) and 0.857 (95%CI 0.783-0.932), respectively. The sensitivity was 91.7% and 73.7%, the specificity was 78.8% and 84.0%, and the accuracy was 85.3% and 78.4%, respectively. Conclusion    There are differences in radiomics features between invasive pulmonary adenocarcinoma with or without micropapillary and solid structures, and the radiomics model is demonstrated to be with good diagnostic value.

Evaluation of condylar position in patients with malocclusion and changes in condylar position before and after orthodontic treatment using cone beam computed tomography / 口腔疾病防治

@#The functional health and stability of the oral and maxillofacial system is one of the basic goals of orthodontic treatment. Currently, it is believed that, in general, the condyle is located in the center of the joint fossa when the mandible is in an intercuspal position (ICP) in healthy normal people. At this time, the function of the temporomandibular joint (TMJ) is stable. Due to orthodontic tooth movement and subsequent occlusal changes, patients with malocclusion may experience related remodeling of the temporomandibular joint, especially changes in the position of the condyle. The position of the mandibular condyle is traditionally evaluated using a condylar position indicator. However, this method lacks consistency in obtaining condylar position changes. In recent years, in the clinical application of orthodontic treatment, cone beam computed tomography (CBCT) has become the first choice for examination. CBCT can accurately measure the interarticular space and determine changes in condylar position. This article reviews the CBCT assessment of condylar position and related research on condylar position changes in patients with malocclusion before and after orthodontic treatment. The literature review results indicate that there are differences in the condylar position of patients with different malocclusions, and the condylar position may also change before and after orthodontic treatment. With a lower radiation dose, CBCT has higher accuracy in evaluating the condylar position in patients with malocclusion who undergo orthodontic treatment, thus promoting further study of the mechanism of condylar position changes in patients with malocclusion in the future and providing more accurate and personalized guidance for patient treatment.

CBCT analysis of the relative position between maxillary central incisors and alveolar bone in Southern Chinese adults / 口腔疾病防治

Objective@#Exploring the position and bone wall thickness characteristics of the maxillary central incisors in Southern Chinese adults to provide a clinical reference for the design of immediate maxillary central incisor implantation surgery.@*Methods@#The hospital ethics committee approved the study, and the patients provided informed consent. CBCT images of 990 adult patients (aged 20-79 years) from the Stomatology Hospital (January 2018 to December 2021) were categorized based on the dental arch form and age-sex groups. Sagittal CBCT images of the maxillary central incisors were used to measure the labial and palatal bone thickness wall at 4 mm the CEJ to apical, the middle of the root, and the angle between the tooth long axis and the long axis of the alveolar process, to compare the thickness of the labial and palatal bone walls in samples of male and female patients, and to explore the relationship between the angle between the tooth long axis and the alveolar process long axis in samples of male and female patients in different age groups (20-39 years; 40-59 years; 60-79 years).@*Results@#Significant differences were found in the labiopalatine side of the alveolar bone of the maxillary incisor root position. A total of 95.8% (948/990) of the maxillary incisors were positioned more buccally, 4.1% (41/990) were positioned more midway, and 0.1% (1/990) were positioned more palatally. The thicknesses of the bone wall at the CEJ of 4 mm below the palatal side, the middle of the root, and at the apex were greater (1.82 ± 0.56 mm, 3.20 ± 1.10 mm, and 7.70 ± 2.00 mm, respectively) than those at the labial side (1.21 ± 0.32 mm, 0.89 ± 0.35 mm, and 1.86 ± 0.82 mm, respectively), with statistical significance (P<0.05). Male bone wall thickness was generally greater than female bone wall thickness (P<0.05). The angle between the long axis of male teeth and the alveolar bone was 14.77° ± 5.66°, while that of female teeth was 12.80° ± 5.70°, with a statistically significant difference (P<0.05). The angle between the long axis of teeth and the alveolar bone in the 40-59-year-old group and the 60-79-year-old group was greater than that in the 20-39-year-old group, and the difference was statistically significant (P<0.05).@*Conclusion@#A total of 95.8% of adults in South China have maxillary central incisors with root deviation toward the labial bone cortex. The thickness of the labial bone wall is much thinner than that of the labial bone wall, which is the middle of the thickness of the root. In Southern Chinese adults, the angle between the upper central incisor and the long axis of the alveolar bone in males is greater than that in females, and the degree of the angle increases with age. It is recommended to pay attention to the thickness of the bone wall around the root and the angle between the teeth before immediate implantation surgery to choose a reasonable implantation plan.

Optical coherence tomography angiography manifestations of different degrees of nonproliferative diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the differences in varying stages of non-proliferative diabetic retinopathy(NPDR)using optical coherence tomography angiography(OCTA).METHODS: Cross-sectional study. A total of 77 cases(77 eyes)of diabetic patients were included, and they were divided into non-diabetic retinopathy(NDR; 23 eyes)and non-proliferative diabetic retinopathy(NPDR; 54 eyes)groups, further subdivided into mild NPDR(20 eyes), moderate NPDR(20 eyes), and severe NPDR(14 eyes). Foveal avascular zone(FAZ)area, superficial and deep capillary plexus densities(SSP and DSP), and visual acuity(LogMAR)were compared between NDR and NPDR groups. Furthermore, the visual acuity, FAZ area and levels of SSP and DSP were compared in different degrees of NPDR. Correlation analysis were conducted to elucidate relationships between FAZ area, visual acuity, SSP, DSP, and severity of the disease.RESULTS: Compared with the NDR group, the visual acuity(LogMAR)and macular FAZ area increased, while SSP and DSP were decreased in the NPDR group(P&#x0026;#x003C;0.05); there were significant differences in visual acuity, FAZ area and SSP and DSP levels in different degrees of NPDR(P&#x0026;#x003C;0.05). Visual acuity(LogMAR)and FAZ area displayed a positive correlation with the severity of disease, while SSP and DSP showed a negative correlation.CONCLUSION: With the progression of NPDR, the visual acuity(LogMAR)and FAZ area increased, and the SSP and DSP decreased.

Application progress of swept-source optical coherence tomography angiography in ophthalmology / 国际眼科杂志(Guoji Yanke Zazhi)

Swept-source optical coherence tomography angiography(SS-OCTA)is a new vascular imaging technique that was recently proposed. It has the advantages of being non-invasive, quick, high-resolution, and automated vascular stratification imaging. It is extremely helpful in the early diagnosis of ophthalmology-related diseases, as well as in the evaluation of treatment effectiveness and the tracking of disease progression. Based on the foundation of OCTA, SS-OCTA utilizes a fast-tuning laser with a wavelength of 1 050 nm for deeper penetration and non-invasive depth-resolved imaging of the retinal and choroidal microvascular systems, deepening the understanding of the characteristics of a wide range of ophthalmic diseases(fundus lesions, glaucoma, neurodegenerative diseases, etc.). The structures of the anterior segment of the eye can also be studied using SS-OCTA, including changes in the depth and density of corneal neovascularization as well as changes in iris neovascularization before and after therapy. This approach provides a novel tool for ophthalmic clinical practice. The development of the clinical use of SS-OCTA technology in ophthalmology is reviewed in this article.

Changes of macular retinal structure and microcirculation in patients with pituitary adenoma observed by optical coherence tomography and optical coherence tomography angiography / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the changes of macular retinal structure and microcirculation in patients with pituitary adenoma(PA)by optical coherence tomography(OCT)and optical coherence tomography angiography(OCTA).METHODS: Cross-sectional study. A total of 40 PA patients treated at the department of neurosurgery, Affiliated Hospital of Guangdong Medical University from September 2021 to March 2023 were included as PA group, and 42 age- and gender-matched healthy volunteers were selected as normal control group. All patients underwent visual field, OCT and OCTA examinations, and the correlation of ocular parameters in PA patients was analyzed.RESULTS:The vessel density(VD)of each retinal layer in the macular area of the PA group was lower than that of the normal control group, and the superficial vascular complex(SVC)-VD in the macular area was positively correlated with the thickness of the macular ganglion cell complex(mGCC)(except the nasal side of the inner ring and the lower part of the outer ring; P&#x0026;#x003C;0.05). The thickness of mGCC in each quadrant of the macular area and the thickness of the circumpapillary retinal nerve fiber layer(CP-RNFL)in each quadrant were negatively correlated with the mean defect(MD)value of the visual field(P&#x0026;#x003C;0.05), and the area of the foveal avascular zone(FAZ)was positively correlated with the MD value(P&#x0026;#x003C;0.05).CONCLUSION:The combination of OCT and OCTA can fully understand the microscopic changes of retinal structure and microcirculation function in PA patients, which is of great value in evaluating the preoperative visual function of PA patients.

Guidelines for the operation of imaging equipment in orbital diseases(2024) / 国际眼科杂志(Guoji Yanke Zazhi)

Orbital disorders include conditions originating from the orbital bones, surrounding tissues, and post-orbital septum. They also include systemic ailments affecting the orbit. Different clinical symptoms make up the complex range of orbital disorders. Because these disorders mostly impact the orbital area instead of the intraocular compartment, there is little diagnostic usefulness for typical ophthalmic visual tests. As such, the primary instruments for diagnosing and evaluating orbital illnesses have become ophthalmic imaging modalities, including ocular ultrasonography(B-scan), computed tomography(CT), and magnetic resonance imaging(MRI). One way to improve the precision and promptness of diagnosing orbital diseases is to standardize the functioning of widely used imaging equipment and define the radiological features of orbital abnormalities. Such programs are crucial for the care of patients with orbital disorders since they considerably reduce the number of misdiagnoses and missed diagnoses in these individuals. The underlying concepts, operational techniques, and normal and pathological imaging findings associated with common diagnostic tools for orbital illnesses are all thoroughly reviewed in this guideline. The objective is to improve primary healthcare settings' diagnostic competence in the field of orbital pathology and to standardize procedures for diagnosing orbital disorders.

Research progress on morphology of macular foveal avascular zone in ocular diseases based on optical coherence tomography angiography measurement / 国际眼科杂志(Guoji Yanke Zazhi)

The foveal avascular zone(FAZ)is the most sensitive region of the retina, which is interconnected by the macular capillary plexus. Its morphology can indirectly reflect the alterations of macular microcirculation. With strong repeatability and reliability, optical coherence tomography angiography(OCTA)can non-invasively visualize and quantify the FAZ. The great value of OCTA makes it an important supplemental examination tool in ophthalmology and other professions. The area and perimeter of FAZ have been demonstrated to be an effective clinical diagnostic indicator in high myopia, diabetic retinopathy, glaucoma and other ocular diseases. In recent years, the geometry of FAZ has also proven to have clinical value. The parameters describing the geometry of FAZ, such as circularity index, acircularity index and axial ratio, provide a new perspective for ocular disease research. The comprehensive investigation of the morphological characteristics of the FAZ is helpful to explore the pathological mechanism of the occurrence and development of ocular diseases, predict preclinical changes, make pathological stages of the disease precise, and provide a theoretical basis for monitoring the disease's progression and assessing patients' visual prognosis.

Quantitative analysis of macular capillaries in diabetic patients using optical coherence tomography angiography / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To quantify early changes of macular capillary parameters in type 2 diabetic patients using optical coherence tomography angiography(OCTA).METHODS: Retrospective case study. A total of 49 healthy subjects, 52 diabetic patients without retinopathy(noDR)patients, and 43 mild nonproliferative diabetic retinopathy(mNPDR)patients were recruited. Capillary perfusion density, vessel length density(VLD), and average vessel diameter(AVD)were calculated from macular OCTA images(3 mm×3 mm)of the superficial capillary plexus after segmenting large vessels and the deep capillary plexus. Parameters were compared among control subjects, noDR, and mNPDR patients. The area under the receiver operating characteristic curve estimated the abilities of these parameters to detect early changes of retinal microvascular networks.RESULTS: Significant differences were found in the VLD and AVD among the three groups(P&#x0026;#x003C;0.001). Compared with the control group, the noDR group had significantly higher AVD(P&#x0026;#x003C;0.05). VLD of both layers in patients of mNPDR group was significant decreased compared with that of noDR group(all P&#x0026;#x003C;0.01). Deep AVD had a higher area under the curve(AUC)of 0.796 than other parameters to discriminate the noDR group from the healthy group. Deep AVD had the highest AUC of 0.920, followed by that of the deep VLD(AUC=0.899)to discriminate the mNPDR group from the healthy group.CONCLUSIONS: NoDR patients had wider AVD than healthy individuals and longer VLD than mNPDR patients in both layers. When compared with healthy individuals, deep AVD had a stronger ability than other parameters to detect early retinal capillary impairments in noDR patients.

Compound anisodine combined with retinal laser photocoagulation for the treatment of severe non-proliferative diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the clinical efficacy of the compound anisodine combined with retinal laser photocoagulation in the treatment of severe non-proliferative diabetic retinopathy(NPDR). METHODS: According to the retrospective study, totally 120 eyes of patients with severe NPDR who admitted to Daxing Teaching Hospital Affiliated to Capital Medical University from May 2023 to July 2023 were selected. The patients were divided into the observation group and the control group according to treatment methods, with 60 eyes in each group. The observation group was treated with panretinal photocoagulation combined with the compound anisodine injection. The control group was only treated with panretinal photocoagulation. The optical coherence tomography angiography(OCTA)and optical coherence tomography(OCT)were used to quantitatively analyze the fundus retinal structure and blood flow. Furthermore, the best corrected visual acuity(BCVA), superficial vascular density(SVD), deep vascular density(DVD), choroidal blood flow density and central macular foveal retinal thickness(CMT)were compared before treatment and at 1 d, 1 and 2 mo after treatment.RESULTS:At 2 mo postoperatively, the rate of visual improvement and the BCVA in the observation group of patients were significantly better than those of the control group, and the incidence of macular edema in the observation group was significantly lower than the control group(P&#x003C;0.05). The BCVA at 1 and 2 mo after treatment were significantly higher than those before treatment in both groups(P&#x003C;0.05). The SVD in the observation group was better than the control group at 1 d, 1 and 2 mo after treatment(all P&#x003C;0.05). The DVD and choroidal flow density in the observation group were better than those of the control group at 1 d after treatment(all P&#x003C;0.05). The CMT of the observation group was smaller than that of the control group at 1 d after treatment(P&#x003C;0.05).CONCLUSION:Compound anisodine can effectively improve the fundus microcirculation after panretinal photocoagulation and reduce the incidence of macular edema, thus promoting the visual function.