Analysis of variation patterns of focal physiological uptake in the tongue on 18F-FDG PET/CT imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective:To analyze variant patterns and characteristics of focal physiological uptake (FPU) in the tongue on 18F-fluorodeoxyglucose (FDG) PET/CT imaging in patients without a history of oral tumor surgery and radiotherapy. Methods:A total of 6 233 consecutive patients who underwent routine whole-body PET/CT scan between January 2013 and December 2017 in the First Hospital of Shanxi Medical University were investigated retrospectively, and 324 patients with a history of oral surgery and radiotherapy were excluded, the remaining 5 909 patients (3 418 males, 2 491 females, age range: 2-95 (average: 58) years) were enrolled. A part of the patients underwent local PET/CT scan and CT scan with diagnostic dose, covering the oral cavity on mouth-opening position. The morphological characteristics of FPU patterns were analyzed, and the maximum standardized uptake value (SUV max) was measured. Results:Seventy-six FPUs in 76 patients (49 males, 27 females, age range: 40-83 (average 64) years) identified by routine whole-body PET/CT scan were confirmed by clinical examination from a specialist in stomatology or follow-up for more than 6 months. Forty-one of the 76 patients subsequently underwent local PET/CT scan and diagnostic CT scan on mouth-opening position. The incidence of FPU in the tongue was 1.29%(76/5 909). The FPU patterns could be classified into three types: type Ⅰ with FDG uptake involved only anterior part of the tongue body in the midline (near the tip of the tongue), which showed as a " dotted" shape( n=68; 1.15%, 68/5 909); type Ⅱ with FDG uptake involved mainly middle part of the genioglossus muscle, which showed as a " bar-shorted" shape ( n=5; 0.08%, 5/5 909); type Ⅲ with FDG uptake involved large part of the tongue body and the genioglossus, which showed as a " T" shape( n=3; 0.05%, 3/5 909). The SUV max in patients with type Ⅰ and type Ⅱ were 5.53(4.53, 7.30), 19.50(17.10, 22.74) respectively. The SUV max in 3 patients with type Ⅲ were 23.34, 27.50 and 35.14, respectively. Conclusion:In patients without a history of oral tumor surgery and radiotherapy, the FPU in the tongue has its specific pattern, and PET/CT scan on mouth-opening position helps to reveal the detailed features.