PURPOSE: The purpose of this study was to evaluate the accuracy of each method of counting ribs on chest CT and to propose a new method: the anterior approach with using the sternocostal joints. MATERIALS AND METHODS: CT scans of 38 rib lesions of 27 patients were analyzed (fracture: 25, metastasis: 11, benign bone disease: 2). Each lesion was independently counted by three radiologists with using three different methods for counting ribs: the sternoclavicular approach, the xiphisternal approach and the modified sternomanubrial approach. The rib lesions were divided into three parts for evaluation of each method according to the location of the lesion as follows: the upper part (between the first and fourth thoracic vertebra), the middle part (between the fifth and eighth) and the lower part (between the ninth and twelfth). RESULTS: The most accurate method was a modified sternomanubrial approach (99.1%). The accuracies of a xiphisternal approach and a sternoclavicular approach were 95.6% and 88.6%, respectively. A modified sternomanubrial approach showed the highest accuracies in all three parts (100%, 100% and 97.9%, respectively). CONCLUSION: We propose a new method for counting ribs, the modified sternomanubrial approach, which was more accurate than the known methods in any parts of the bony thorax, and it may be an easier and quicker method than the others in clinical practice.
Bone Diseases ; Humans ; Neoplasm Metastasis ; Ribs* ; Sternocostal Joints ; Thorax* ; Tomography, X-Ray Computed*

This study was aimed to determine the effects of respiratory phase, age, sex and body mass indexes (BMI) on the visibility and morphological characteristics of the diaphragmatic sternocostal triangle in normal adults shown by multi-detector computed tomography (MDCT). A total of 100 normal adults were consecutively recruited and scanned with 16-row MDCT at the end of deep expiration and inspiration. The visibility and morphological characteristics of diaphragmatic sternocostal triangle were observed. All cases were grouped according to the respiratory phase, age, sex and BMI, respectively. The visibility rates by MDCT among different types of sternocostal triangles at the inspiratory or the expiratory phases were calculated and compared, and the visibility rate was correlated with age, sex, and BMI, respectively. In addition, the CT features of diaphragmatic hernia (n=2) were recorded and analyzed. The visibility rate of trigonum sternocostal was 43% at the end of inspiration and 32% at the end of expiration. No difference was found in regard to age, gender and BMI (P > 0.05). Rupture of diaphragm and the features of adjacent abdominal organs into thoracic cavity were revealed clearly on multiplanar reformation (MPR) images of MDCT in 2 patients with diaphragmatic hernia. The visibility rates of diaphragmatic sternocostal triangle were associated with the respiratory movement. MPR on MDCT could be useful for revealing the anatomic structure of diaphragm and the radiological features of diaphragmatic hernia. Furthermore, double-phase scanning of MDCT provides feasible method for studying the physiologic information of diaphragm movement in normal status and abnormal status.
Adolescent ; Adult ; Aged ; Diaphragm ; anatomy & histology ; diagnostic imaging ; Female ; Hernia, Diaphragmatic ; diagnostic imaging ; Humans ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Respiration ; Sternocostal Joints ; anatomy & histology ; diagnostic imaging ; Tomography, Spiral Computed ; methods ; Young Adult