Diagnosis of Sarcopenia in Head and Neck Computed Tomography: Cervical Muscle Mass as a Strong Indicator of Sarcopenia

OBJECTIVES: Patients with head and neck cancer (HNC) have a high risk of sarcopenia, which is associated with poor prognosis. Skeletal-muscle area and index at the third lumbar (L3) vertebra level (L3MA and L3MI) are recommended for the detection of sarcopenia. However, L3 level is not included in many imaging protocols and there are no data for optimal levels and cutoffs for the diagnosis of sarcopenia in head and neck computed tomography (HNCT) scans. Our aim was to assess the relationship between cervical paravertebral muscle values and L3MI and to investigate optimal level to diagnose sarcopenia on HNCTs. METHODS: Patients with HNC (n=159) who underwent positron emission tomography-CT for tumor staging were retrospectively analyzed. On CT images, paravertebral and sternocleidomastoid muscle areas at second (C2), third (C3), and fourth (C4) cervical vertebrae levels (C2MA, C3MA, C4MA, SCMA) and L3MA were measured. Cross-sectional areas were normalized for stature (muscle area/height square) and muscle index (C2MI, C3MI, C4MI, SCMI, L3MI) values were obtained. Spearman correlation and linear regression analyses were used for assessing correlations. To calculate the diagnostic performance of SCMI, C2MI, C3MI, and C4MI for the diagnosis of sarcopenia with respect to the cutoffs of L3MI, receiver operating characteristic (ROC) analysis was used. RESULTS: Males had significantly higher muscle areas than females. Although C2MI, C3MI, C4MI, and SCMI values all showed very strong and significant correlation with L3MI (P<0.001). According to the ROC analysis, the best discriminative for sarcopenia was C3MI in males (area under curve [AUC], 0.967) and SCMI in females (AUC, 0.898). CONCLUSION: C2MI, C3MI, C4MI, and SCMI values can be used as alternatives for the diagnosis of sarcopenia in routine HNCT examinations.

Tracheobronchial Angle Measurements in Children: An Anthropometric Retrospective Study With Multislice Computed Tomography

OBJECTIVES: The purpose of this study is to investigate if any change exists in the values of tracheal bifurcation angles (subcarinal angle [SCA] and interbronchial angle [IBA]), right and left bronchial angles (RBA and LBA) in different pediatric age groups. METHODS: Chest computed tomography (CT) images of children aged 18 years and younger were reviewed retrospectively by two radiologists who were blinded to each other's measurements. One hundred and eighteen children were involved. RBA, LBA, SCA, and IBA were measured on coronal reformatted images. Subjects were classified into three groups according to their age. Measurement of IBA was done by measuring the angle between the lines drawn along the central axis of right and left main bronchi over their length. RBA and LBA were measured at the intersection points of the lines drawn along the inferior borders of the right and left main bronchi and the line passing through the longitudinal axis of trachea. Sums of RBA and LBA gave SCA. Interobserver agreement was also analyzed. RESULTS: SCA, IBA, and RBA values were statistically significant between children of ages less than 10 years and over 10 years P<0.01). Interobserver agreement was excellent with an intraclass correlation coefficient score of 0.87 (95% confidence interval) for RBA, SCA, and IBA measurements. CONCLUSION: We concluded that tracheal bifurcation angles are wider in children of age 10 years and younger. As age increases values of SCA, IBA, and RBA decrease.