Suarez Martin W, Dever David D, Gu Xiaohan, Ray Illian P, McClintic Abbi M, Mehic Edin, Mourad Pierre D
Department of Bioengineering, Univ. of WA, 1959 NE Pacific St., Box 356470, Seattle, WA 98195, United States; Department of Neurological Surgery, Univ. of WA, 1959 NE Pacific St., Box 356470, Seattle, WA 98195, United States.
Department of Bioengineering, Univ. of WA, 1959 NE Pacific St., Box 356470, Seattle, WA 98195, United States.
Ultrasonics. 2015 Aug;61:151-6. doi: 10.1016/j.ultras.2015.04.014. Epub 2015 May 5.
Vibro-acoustography (VA) uses two or more beams of confocal ultrasound to generate local vibrations within their target tissue through induction of a time-dependent radiation force whose frequency equals that of the difference of the applied frequencies. While VA has proven effective for assaying the mechanical properties of clinically relevant tissue such as breast lesions and tissue calcifications, its application to brain remains unexplored. Here we investigate the ability of VA to detect acute and focal traumatic brain injury (TBI) in-vivo through the use of transcranially delivered high-frequency (2 MHz) diagnostic focused ultrasound to rat brain capable of generating measurable low-frequency (200-270 kHz) acoustic emissions from outside of the brain. We applied VA to acute sham-control and TBI model rats (sham N=6; TBI N=6) and observed that acoustic emissions, captured away from the site of TBI, had lower amplitudes for TBI as compared to sham-TBI animals. The sensitivity of VA to acute brain damage at frequencies currently transmittable across human skulls, as demonstrated in this preliminary study, supports the possibility that the VA methodology may one day serve as a technique for detecting TBI.
振动声学成像（VA）使用两束或更多束共聚焦超声，通过诱导频率等于所施加频率之差的随时间变化的辐射力，在其目标组织内产生局部振动。虽然VA已被证明在检测临床相关组织（如乳腺病变和组织钙化）的力学特性方面有效，但其在脑部的应用仍未得到探索。在此，我们通过对大鼠脑部经颅递送高频（2 MHz）诊断性聚焦超声，研究VA在体内检测急性局灶性创伤性脑损伤（TBI）的能力，这种超声能够从脑外产生可测量的低频（200 - 270 kHz）声发射。我们将VA应用于急性假手术对照和TBI模型大鼠（假手术组N = 6；TBI组N = 6），并观察到，在远离TBI部位捕获的声发射中，与假手术 - TBI动物相比，TBI大鼠的声发射幅度更低。如本初步研究所示，VA对目前可透过人类颅骨的频率下的急性脑损伤的敏感性，支持了VA方法有朝一日可能成为检测TBI的一种技术的可能性。
