Article Figures & Data
Figures
- Fig 1.
A 50-year-old woman with vague facial pain for several months and enophthalmos on physical examination. CT (A) and conebeam CT (B) coronal images show inward retraction of the right maxillary walls and apposition of the right uncinate process into the orbital floor, occluding the maxillary sinus infundibulum. The clinical and CT imaging findings were characteristic of silent sinus syndrome. CT scans delineate anatomic structures and demonstrate disease not shown on the x-ray (C). X-ray shows a small right maxillary sinus but is unable to help in the diagnostic work-up of the patient.
Tables
- Table 1:
Image-quality scores for scoring method 1 (visualization of 6 bony anatomic structures) and scoring method 2 (subjective impression of the overall quality of the study) for each imaging technique, with left and right sides combineda
Standard CT Conebeam CT Difference Score 1b Reader 1 11 ± 2.8 (3–12) 10.5 ± 3.4 (3–12) 0.5c Reader 2 11 ± 2.9 (3–12) 10.25 ± 3.5 (3–12) 0.75d Difference 0 0.25 0.5c Score 2e Reader 1 5 ± 0.45 (4–5) 4 ± 0.7 (4–5) 1d Reader 2 5 ± 0.22 (3–5) 4 ± 0.54 (3–5) 1d Difference 0 0 0 - Table 4:
Image noise, signal-to-noise ratio, and contrast-to-noise ratio for each imaging techniquea
Noise SNRb CNR(b/m) CNR(b/a) CNR(m/a) CT 29.28 ± 9.39 100.35 ± 33.1 97.03 ± 31.63 163.80 ± 54.81 66.76 ± 23.31 Conebeam CT 46.76 ± 15.84 25.33 ± 16.73 28.45 ± 18.11 50.46 ± 31.9 22 ± 14 Difference 17.48b 75.02b 68.58b 113.34b 44.76b - Table 5:
Absorbed radiation dose to the lenses of the eye and parotid and thyroid glands for each imaging techniquea
Absorbed Dose Right Lens (mGy) Absorbed Dose Left Lens (mGy) Absorbed Dose Right Parotid Gland (mGy) Absorbed Dose Thyroid Gland (mGy) CT 9.25 ± 1.69 9.69 ± 1.08 8.87 ± 1.68 0.45 ± 0.13 Conebeam CT 0.28 ± 0.01b 0.4 ± 0.03b 0.69 ± 0.05 0.05 ± 0.05 Difference 8.97c 9.29c 8.18c 0.4c
