State Key Laboratory of Molecular Vaccinology and Molecular Diagnosis & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiang'an South Road, Xiang'an District, Xiamen, 361102, Fujian Province, People's Republic of China.
Eur Radiol. 2018 May;28(5):2176-2183. doi: 10.1007/s00330-017-5209-x. Epub 2017 Dec 21.
This study aimed to demonstrate the capacity for noninvasive localisation and characterisation of myocardial infarction (MI) in vivo using a hemispherical photoacoustic imaging (PAI) system. MI remains a leading cause of morbidity and mortality worldwide. To enable optimal treatment of patients, timely and accurate diagnosis and longitudinal monitoring is critical.
Ischaemia was induced in Balb/c mice by ligation of the left anterior descending artery. The hemispherical PAI system, equipped with 128 ultrasonic transducers spirally distributed on the surface, along with parallel data acquisition, was applied for imaging of the mouse heart.
Our study showed that hemispherical PAI can delineate thoracic vessels and the morphology of the entire heart. Longitudinal PAI images revealed gradual expansion of the infarcted area along with necrosis and fibrosis, which were quantitatively validated by triphenyltetrazolium chloride staining. After MI modelling, the photoacoustic (PA) signal intensity decreased by 399.1 ± 56.3 (p < 0.001), a ~2.5-fold reduction compared to that of healthy cardiac tissue. The calculated size of the enlarged heart, 10.4 ± 6.0 mm (p < 0.001), represents an increase of ~18% versus that of a healthy heart.
PAI enables MI diagnosis and injury localisation with its capabilities for both deep organ imaging and lesion region differentiation.
• Photoacoustic imaging (PAI), combining optical absorption and ultrasonic resolution, can delineate cardiac anatomy. • PAI can diagnose myocardial infarction lesions with 10 mm imaging depth in vivo. • Quantified results are in excellent agreement with enzyme and histological examinations. • PAI can serve as a complementary modality to SPECT and ultrasound imaging. • This study will encourage further PAI development for clinical use.
本研究旨在展示使用半球形光声成像（PAI）系统在体内无创定位和特征化心肌梗死（MI）的能力。MI 仍然是全球发病率和死亡率的主要原因。为了能够为患者提供最佳治疗，及时、准确的诊断和纵向监测至关重要。
通过结扎左前降支在 Balb/c 小鼠中诱导缺血。半球形 PAI 系统配备了 128 个超声换能器，它们沿表面螺旋分布，并配备了并行数据采集，用于对小鼠心脏进行成像。
我们的研究表明，半球形 PAI 可以描绘胸腔血管和整个心脏的形态。纵向 PAI 图像显示梗死区域逐渐扩大，同时伴有坏死和纤维化，三苯基四唑氯化物染色定量验证了这一点。在 MI 建模后，光声（PA）信号强度降低了 399.1±56.3（p<0.001），与健康心脏组织相比降低了约 2.5 倍。计算出的扩大心脏大小为 10.4±6.0mm（p<0.001），与健康心脏相比增加了约 18%。
PAI 能够进行 MI 诊断和损伤定位，具有深层器官成像和病变区域区分的能力。
• 光声成像（PAI）结合光学吸收和超声分辨率，可以描绘心脏解剖结构。• PAI 可以在体内对心肌梗死病变进行 10mm 成像深度的诊断。• 量化结果与酶和组织学检查非常吻合。• PAI 可以作为 SPECT 和超声成像的补充模态。• 本研究将鼓励进一步开发 PAI 用于临床应用。
