The impact of a simple positioning aid device on the diagnostic performance of thyroid cancer in CT scans: a randomized controlled trial

Abstract

Objective: To evaluate the effectiveness of a simple positioning aid device in neck CT scans for the diagnosis of thyroid cancer, with a focus on its influence on image quality and diagnostic accuracy.

Methods: A randomized controlled trial was conducted involving 180 patients with suspected thyroid cancer. Participants were randomly assigned to two groups: the device-assisted positioning group (Group A) and the traditional positioning group (Group B). A total of 147 patients who underwent enhanced neck CT scans and subsequent surgical pathological biopsies were included in the final analysis. Image quality and thyroid disease diagnoses were independently assessed by two experienced radiologists, with a unified consensus for the final conclusions. Objective imaging parameters and subjective ratings were used to evaluate image quality. Pathological findings served as the gold standard to compare the diagnostic accuracy of the two groups for thyroid malignancy, capsular invasion, and lymph node metastasis. Additionally, radiation doses in both groups were compared.

Results: A total of 147 patients were included in the analysis, with 72 patients in Group A and 75 in Group B. The baseline characteristics of the two groups were similar (P > 0.05). Group A demonstrated significantly superior image quality compared to Group B, with shorter length of artifacts (LA), lower proportion of affected thyroid (PA), and lower artifact index (AI). Subjective assessments also favored Group A, showing better ratings for regional artifacts and overall image quality. In terms of diagnostic accuracy, Group A outperformed Group B in detecting thyroid cancer (AUC: 0.852 vs. 0.676, P = 0.021). For the right thyroid lobe, Group A had significantly better diagnostic performance (AUC: 0.897 vs. 0.746, P = 0.016). Group A also showed superior performance in diagnosing capsular invasion (AUC: 0.861 vs. 0.721, P = 0.037), with similar results observed for both the left and right thyroid lobes. There was no significant difference between the groups in diagnosing lymph node metastasis. Furthermore, thyroid region radiation doses (CTDIvol and SSDE) were significantly lower in Group A compared to Group B.

Conclusion: The use of a positioning aid device significantly improves CT image quality, enhancing diagnostic accuracy for malignant thyroid lesions and capsular invasion, while also reducing radiation exposure.

Keywords: Diagnostic performance; Image quality; Positioning aid device; Thyroid CT scan; Thyroid cancer.

Fig. 1

Schematic illustration of patient recruitment and study design

Fig. 2

Illustration of the auxiliary device-assisted position, traditional position, surgical position, and auxiliary devices. (A, B) Representative patient positioning photographs (A) and the scout image (B) in Group A with assisted positioning. (C, D) Representative patient positioning photographs (C) and the scout image (D) in Group B with traditional positioning. In Group A, the shoulders are lowered, and the neck is elevated, resulting in less overlap between the neck and shoulders in the sagittal view; in the traditional position, the shoulders are moved forward, causing the neck to be obscured by the shoulders in the sagittal view. (E) Photograph of the auxiliary device. (F) Photograph of the surgical position. (G) Structural diagram of the auxiliary device

Fig. 3

The subjective image quality scores in both groups

Fig. 4

The diagnostic efficacy for thyroid cancer, capsular invasion and lymph node metastasis between the two groups