Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece.
Department of Medical Physics, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece.
Eur Radiol. 2022 Nov;32(11):7522-7531. doi: 10.1007/s00330-022-08817-0. Epub 2022 Apr 29.
To explore the association between testicular volumetric apparent diffusion coefficient (ADC) histogram analysis metrics and histologic categories in nonobstructive azoospermia (NOA). The role of ADC histogram analysis in predicting the presence of spermatozoa, prior to testicular sperm extraction (TESE), was also investigated.
Forty-one NOA men and 17 age-matched controls underwent scrotal MRI with diffusion-weighted imaging. Histogram analysis of ADC data of the whole testis was performed. Metrics including mean, standard deviation, median, mode, 25th percentile, 75th percentile, skewness, kurtosis, and entropy of volumetric ADC histograms were calculated. Nonparametric statistical tests were used to assess differences in ADC histogram parameters between NOA histologic categories (hypospermatogenesis, severe hypospermatogenesis, early maturation arrest, and Sertoli cell-only syndrome) and normal testes and, between NOA with positive and negative sperm retrieval.
Normal testes had a lower mean, median, mode, 25th percentile (p < 0.001), and 75th percentile of ADC (p = 0.001), compared to NOA histologic phenotypes. NOA with hypospermatogenesis had a lower 25th percentile of ADC compared to NOA with severe hypospermatogenesis. Regression analysis revealed that the 25th percentile of ADC had a moderately negative correlation with NOA histologic phenotype. The median ADC proved the most significant metric (p = 0.007) to predict the presence of sperm.
Testicular volumetric ADC histogram parameters may contribute in the identification of the subpopulation of NOA men with a specific type of spermatogenic arrest.
• Volumetric ADC histogram analysis metrics may be used as noninvasive markers of impaired spermatogenesis in nonobstructive azoospermia. • The 25th percentile of ADC proved useful in discriminating between NOA testes with hypospermatogenesis and severe hypospermatogenesis. • The median ADC proved the most significant parameter to predict the presence of viable spermatozoa prior to TESE.
探讨非梗阻性无精子症（NOA）睾丸体积 ADC 直方图分析指标与组织学分类之间的关系。还研究了 ADC 直方图分析在预测睾丸精子提取（TESE）前精子存在的作用。
41 名 NOA 男性和 17 名年龄匹配的对照者接受了阴囊 MRI 加扩散加权成像。对整个睾丸 ADC 数据进行直方图分析。计算了 ADC 直方图的平均值、标准差、中位数、众数、25%分位数、75%分位数、偏度、峰度和熵等指标。使用非参数统计检验评估了 ADC 直方图参数在 NOA 组织学分类（生精障碍、严重生精障碍、早期成熟阻滞和唯支持细胞综合征）与正常睾丸之间的差异，以及在 NOA 精子提取阳性和阴性之间的差异。
正常睾丸的 ADC 平均值、中位数、众数、25%分位数（p<0.001）和 75%分位数均低于 NOA 组织学表型（p<0.001）。与严重生精障碍相比，生精障碍的 25%分位数较低。回归分析显示，ADC 的 25%分位数与 NOA 组织学表型呈中度负相关。中位数 ADC 是预测精子存在的最显著指标（p=0.007）。
睾丸体积 ADC 直方图参数可能有助于识别具有特定生精阻滞类型的 NOA 男性亚群。
体积 ADC 直方图分析指标可作为非梗阻性无精子症中受损生精作用的非侵入性标志物。
ADC 的 25%分位数有助于区分生精障碍和严重生精障碍的 NOA 睾丸。
中位数 ADC 是预测 TESE 前有活力精子存在的最显著参数。
