Title

Unilateral Vocal Cord FDG Uptake Caused by Contralateral Vocal Cord Paralysis

Translated Titles

因對側聲帶麻痺所造成之單側聲帶葡萄糖攝取

DOI

10.6332/ANMMI.202106_34(2).0005

Authors

李岳(Yueh Lee);邱創新(Chuang-Hsin Chiu);鄭澄意(Cheng-Yi Cheng);林立凡(Li-Fan Lin)

Key Words

fluorine-18 fluorodeoxyglucose (FDG) ; positron emission tomography/computed tomography (PET/CT) ; recurrent laryngeal nerve ; vocal cord paralysis ; 聲帶麻痺 ; 喉返神經 ; 氟-18氟化葡萄糖 ; 正子造影

PublicationName

核子醫學暨分子影像雜誌

Volume or Term/Year and Month of Publication

34卷2期(2021 / 06 / 01)

Page #

96 - 100

Content Language

英文

Chinese Abstract

A 70-year-old smoking male presented with cough and hoarseness was diagnosed with adenocarcinoma of the left upper lobe of the lung. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) was performed for staging. In addition to FDG-avid primary lung tumor and left hilar lymph node, a focus of intense FDG uptake was incidentally noted at the posterior aspect of the left vocal cord. Laryngoscopy was done to exclude synchronous laryngeal malignancy. Normal appearance of the left vocal cord with contralateral vocal cord paralysis was found. Follow-up FDG PET/CT performed 2.5 years later revealed no discernible abnormal FDG uptake at the vocal cords, supported that the previously noted focal FDG uptake at the left vocal cord might be a benign etiology (e.g., compensatory overuse of the non-paralyzed vocal cord). One of the major causes of asymmetrical vocal cord FDG uptake is compensatory overuse of the unaffected vocal cord caused by unilateral vocal cord paralysis, which is not uncommon in patients with primary lung cancer and mediastinal surgery. We recommended nuclear physicians to be aware of this pitfall to avert a false-positive PET interpretation. Furthermore, diazepam administration or minimized vocalization before PET scan might be helpful to avoid this pitfall.

English Abstract

一位70歲有咳嗽和聲音沙啞症狀的男性經胸腔電腦斷層及內視鏡淋巴結採樣確診為左上肺葉肺癌。正子斷層掃描發現除左上肺葉腫瘤及左肺門疑似淋巴轉移病灶之外,在左後側聲帶也有局部強烈葡萄糖攝取。為排除原發性喉癌之可能,進一步之喉鏡檢查顯示左側聲帶處無異常病灶,但意外發現對側(右側)聲帶麻痺。病人於2.5年後追縱之正子斷層掃描顯示左側聲帶已無明顯異常之葡萄糖攝取,因此推斷當初左側聲帶之葡萄糖攝取應為良性病因,如聲帶代償性過度使用導致。文獻回顧發現,除了喉部癌症外,造成單側聲帶葡萄糖攝取增加最主要的原因之一是對側聲帶麻痺導致的正常側聲帶代償性過度使用,這種情況在肺癌或是接受過縱膈腔手術的病人中並不罕見。對於這種陷阱之了解有助於避免正子影像之偽陽性判讀。另外,若在正子掃描前讓病人使用diazepam等鎮靜藥物或使其盡量避免發聲,亦可減少此類情形發生。

Topic Category 醫藥衛生 > 基礎醫學
醫藥衛生 > 內科
工程學 > 核子工程