Fraczek Marcin, Guzinski Maciej, Morawska-Kochman Monika, Krecicki Tomasz
Department of Otolaryngology, Wroclaw Medical University, 213 Borowska Str, 50-556, Wrocław, Poland.
Department of Radiology, Wroclaw Medical University, 213 Borowska Str, 50-556, Wrocław, Poland.
Eur Arch Otorhinolaryngol. 2017 Feb;274(2):787-793. doi: 10.1007/s00405-016-4268-y. Epub 2016 Aug 23.
The aim of the study was to compare visualisation of the surgically relevant anatomical structures via low- and standard-dose multidetector CT protocol in patients with chronic rhinosinusitis (CRS) and higher risk for perioperative complications (i.e. presence of bronchial asthma, history of sinus surgery and advanced nasal polyposis). 135 adult CRS patients were divided randomly into standard-dose (120 kVp, 100 mAs) or low-dose CT groups (120 kVp, 45 mAs). The detectability of the vital anatomical structures (anterior ethmoid artery, optic nerve, cribriform plate and lamina papyracea) was scored using a five-point scale (from excellent to unacceptable) by a radiologist and sinus surgeon. Polyp sizes were quantified endoscopically according to the Lildholdt's scale (LS). Olfactory function was tested with the "Sniffin' Sticks" test. On the low-dose CT images, detectability ranged from 2.42 (better than poor) for cribriform plate among anosmic cases to 4.11 (better than good) for lamina papyracea in cases without nasal polyps. Identification of lamina papyracea on low-dose scans was significantly worse in each group and the same was the case with cribriform plates in patients with advanced polyposis and anosmia. Cribriform plates were the most poorly identified (between poor and average) among all the structures on low-dose images. Identification of anterior ethmoid artery (AEA) with reduced dose was insignificantly worse than with standard-dose examination. The AEA was scored as an average-defined structure and was the second weakest visualised. In conclusion, preoperatively, low-dose protocols may not sufficiently visualise the surgically relevant anatomical structures in patients with CRS and bronchial asthma, advanced nasal polyps (LS > 2) and history of sinus surgery. Low mAs value enables comparable detectability of sinonasal landmarks with standard-dose protocols in patients without analysed risk factors. In the context of planned surgery, the current preferences of the tube should be carefully evaluated for different patient constitutions to minimise the risk of complications.
本研究的目的是比较低剂量和标准剂量多层螺旋CT方案对慢性鼻窦炎（CRS）且围手术期并发症风险较高（即存在支气管哮喘、鼻窦手术史和重度鼻息肉病）患者手术相关解剖结构的显示情况。135例成年CRS患者被随机分为标准剂量组（120 kVp，100 mAs）或低剂量CT组（120 kVp，45 mAs）。由放射科医生和鼻窦外科医生使用五点量表（从优秀到不可接受）对重要解剖结构（筛前动脉、视神经、筛板和纸样板）的可检测性进行评分。根据Lildholdt量表（LS）在内镜下对息肉大小进行量化。用“嗅觉棒”测试嗅觉功能。在低剂量CT图像上，嗅觉丧失患者中筛板的可检测性评分为2.42（优于差），无鼻息肉患者中纸样板的可检测性评分为4.11（优于良好）。低剂量扫描时，每组中纸样板的识别情况明显较差，重度息肉病和嗅觉丧失患者的筛板识别情况也是如此。在低剂量图像上，筛板是所有结构中识别最差的（介于差和一般之间）。低剂量时筛前动脉（AEA）的识别情况比标准剂量检查略差，但不显著。AEA被评为清晰度一般的结构，是显示第二弱的结构。总之，术前低剂量方案可能无法充分显示CRS合并支气管哮喘、重度鼻息肉（LS>2）和鼻窦手术史患者的手术相关解剖结构。低mAs值在无分析风险因素的患者中能实现与标准剂量方案相当的鼻窦标志可检测性。在计划手术的背景下，应根据不同患者体质仔细评估当前的管电流设置偏好，以尽量降低并发症风险。
