From the Department of Radiology (A.F.J.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
Department of Radiology (F.D.), Great Ormond Street Hospital for Children, London, UK.
AJNR Am J Neuroradiol. 2022 Nov;43(11):1646-1652. doi: 10.3174/ajnr.A7653. Epub 2022 Sep 29.
An "unwound" or "offset" cochlea has been described as a characteristic imaging feature in patients with branchio-oto-renal syndrome, and recently recognized to be associated in particular to those with gene mutations. Determination of this feature has traditionally relied on subjective visual assessment. Our aim was to establish an objective assessment method for cochlear offset (the cochlear turn alignment ratio) and determine an optimal cutoff turn alignment ratio value that separates individuals with -branchio-oto-renal syndrome from those with -branchio-oto-renal syndrome and healthy controls.
Temporal bone CT or MR imaging from 40 individuals with branchio-oto-renal syndrome and 40 controls was retrospectively reviewed. Cochlear offset was determined visually by 2 independent blinded readers and then quantitatively via a standardized technique yielding the cochlear turn alignment ratio. The turn alignment ratio values were compared between cochleae qualitatively assessed as "not offset" and "offset." Receiver operating characteristic analysis was used to determine the ability of the turn alignment ratio to differentiate between these populations and an optimal cutoff turn alignment ratio value. Cochlear offset and turn alignment ratio values were analyzed for each branchio-oto-renal syndrome genotype subpopulation and for controls.
The turn alignment ratio can accurately differentiate between cochleae with and without an offset (< .001). The optimal cutoff value separating these populations was 0.476 (sensitivity = 1, specificity = 0.986, = 0.986). All except 1 cochlea among the -branchio-oto-renal syndrome subset and all with unknown genotype branchio-oto-renal syndrome had a cochlear offset and a turn alignment ratio of <0.476. All except 1 cochlea among the -branchio-oto-renal syndrome subset and all controls had no offset and a turn alignment ratio of >0.476.
There is a statistically significant difference in turn alignment ratios between offset and nonoffset cochleae, with an optimal cutoff of 0.476. This cutoff value allows excellent separation of -branchio-oto-renal syndrome from -branchio-oto-renal syndrome and from individuals without branchio-oto-renal syndrome or sensorineural hearing loss. The turn alignment ratio is a reliable and objective metric that can aid in the imaging evaluation of branchio-oto-renal syndrome.
在 型Branchio-Oto-Renal 综合征（BOR）患者中，耳蜗呈现“未扭转”或“偏斜”的形态被认为是一种影像学特征，最近发现该特征与特定的基因突变有关。传统上，该特征的确定依赖于主观的视觉评估。本研究旨在建立一种评估耳蜗偏斜的客观方法（耳蜗转角比），并确定一个最佳的转角比临界值，以区分 BOR 患者和非 BOR 患者及健康对照者。
回顾性分析 40 例 BOR 患者和 40 例对照者的颞骨 CT 或 MR 图像。2 名独立的盲法阅片者分别对耳蜗偏斜进行定性评估，然后采用标准化技术进行定量评估，得到耳蜗转角比。将定性评估为“未偏斜”和“偏斜”的耳蜗转角比进行比较。受试者工作特征（ROC）曲线分析用于评估转角比区分这两种人群的能力，并确定最佳的转角比临界值。分析每个 BOR 综合征基因型亚组和对照组的耳蜗偏斜和转角比。
转角比能准确地区分有无耳蜗偏斜的耳蜗（<0.001）。将这两种人群区分开来的最佳临界值为 0.476（敏感性=1，特异性=0.986，AUC=0.986）。除 1 例外，所有 型 BOR 综合征亚组的耳蜗均存在耳蜗偏斜和转角比<0.476，所有未知基因型 BOR 综合征的耳蜗也存在耳蜗偏斜和转角比<0.476。除 1 例外，所有 型 BOR 综合征亚组和所有对照组的耳蜗均无耳蜗偏斜和转角比>0.476。
转角比在偏斜耳蜗和非偏斜耳蜗之间存在统计学显著差异，最佳临界值为 0.476。该临界值能极好地区分 BOR 综合征和非 BOR 综合征，以及无 BOR 综合征或感音神经性听力损失的个体。转角比是一种可靠且客观的指标，有助于对 BOR 综合征进行影像学评估。
