Image optimization and reduction of radiation dose in CT of the paranasal sinuses

Computed tomography assessment of maxillary sinus hypoplasia and associated anatomical variations: a systematic review and meta-analysis of global evidence

OBJECTIVE

To summarize the scientific evidence on the prevalence of maxillary sinus hypoplasia (MSH) and associated anatomical variations as assessed by computed tomography scans.

STUDY DESIGN

This PROSPERO-registered systematic review followed the recommendations of the PRISMA guidelines. Search algorithms were constructed for each of the six databases and gray literature. After screening the references (Rayyan®), the extracted data were meta-analyzed according to a random-effects model. The joanna briggs critical appraisal tool assessed the methodological quality of the included studies. The GRADE approach was used to estimate the certainty of the evidence.

RESULTS

From a total of 2781 studies screened, 22 were considered for four meta-analysis. The prevalence of MSH in 7358 patients was 5.65% (CI95% = 4.07-7.47%) with significant heterogeneity between studies (p < 0.001, I2 = 89.30%). MSH was identified in 295 patients, of whom 82.38% (CI95% = 75.82-88.09%) had unilateral hypoplasia and 17.62% (CI95% = 11.91-24.18%) bilateral hypoplasia with moderate heterogeneity between studies (p < 0.0503, I2 = 42.87%). The prevalence of MSH in 9998 maxillary sinuses was 3.77% (95% CI = 2.44-5.38%), with significant heterogeneity between studies (p < 0.001, I2 = 92.84%). Hypoplastic/aplastic uncinate process, concha bullosa and paradoxical concha were the most reported anatomical variations. The studies presented a low-moderate methodological quality. The certainty of the evidence was very low to moderate.

CONCLUSION

The prevalence of maxillary sinus hypoplasia observed was 5.65%, with most cases being unilateral.

Effect Evaluation of Preoperative Psychological Nursing Intervention on Sinusitis Patients Undergoing General Anesthesia by Multiplanner Reformation-Based CT

The aim of this study was at exploring the clinical effect of CT images based on multiplanner reformation (MPR) combined with a preoperative psychological nursing intervention model in sinusitis patients undergoing general anesthesia. Sixty sinusitis patients who received MPR-based CT examination and general anesthesia were selected as the study subjects and randomly divided into the control group (n = 30) and the experimental group (n = 30). The control group used traditional preoperative education. The experimental group added the psychological nursing intervention based on traditional preoperative education. The blood pressure and heart rate before and after the operation, the self-rating anxiety scale (SAS) score before and after intervention, and satisfaction were comprehensively assessed. The results showed that CT based on MPR could observe the lesions and anatomical structures of the sinus wall and sinus in detail from multiple angles. The blood pressure (systolic blood pressure 135.12 ± 14.89 mmHg, diastolic blood pressure 87.05 ± 11.24 mmHg), heart rate (78.42 ± 12.19 beats/min), SAS score (45.85 ± 4.97 points), and nursing satisfaction (78.9%) of the experimental group were significantly better than those of the control group (145.83 ± 15.62 mmHg, 94.21 ± 10.86 mmHg, 86.44 ± 13.65 beats/min, 56.44 ± 5.12 points, 56.4%), and the differences were statistically significant (P < 0.05). In summary, the preoperative psychological care model has a positive role in reducing the tension and anxiety of patients before general anesthesia surgery and CT based on MPR is important for the clinical diagnosis and treatment of sinusitis. This study provides a theoretical reference for the clinical treatment of patients with sinusitis.

Feasibility of low-dose CT protocols for evaluating the sinonasal cavity and reducing radiation exposure in dogs

With the increasing use of radiation therapy for treatment of canine sinonasal neoplasia, there is a need for developing low-dose CT protocols to help minimize radiation exposure. The purpose of this study was to assess the trade-off between image quality and reduced radiation exposure of a low-dose CT technique in the canine sinonasal cavity. In this prospective, experimental study, CT images of the sinonasal cavities from 10 normal Beagles were acquired using high-dose (130 kVp) or low-dose (110 kVp, 80 kVp) protocol. Radiation dose and image quality were compared. Radiation exposure measured by the volume-weighted CT dose index and dose-length product was reduced by 36% at 110 kVp and 74% at 80 kVp respectively, compared to the corresponding values at 130 kVp (P = 0.000). Low-dose protocol resulted in higher image noise and reduced signal-to-noise ratio and contrast-to-noise ratio than 130 kVp in most evaluated regions of interest (P < 0.05). CT numbers of the contrast-enhanced structures were highest at 80 kVp (P = 0.000). Conspicuity of most sinonasal structures was similar for high dose and both lower dose protocols. The results of this study indicate that 80 or 110 kVp can be used for sinonasal CT examinations to reduce radiation exposure to the patient without compromising image quality.