Quantitative evaluation of acoustic coupling characteristics and near field high echo artifacts in pad type ultrasound coupling materials

Ki-Seon Jeon

doi:10.7776/ASK.2026.45.3.240

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2026 Vol.45, Issue 3 Preview Page Next Page

Quantitative evaluation of acoustic coupling characteristics and near field high echo artifacts in pad type ultrasound coupling materials 패드형 초음파 전달매질의 음향 결합 균질성과 근거리 경계면 허상 특성 평가

31 May 2026. pp. 240-246

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Abstract

This study quantitatively compared the ultrasound image quality and near field high echo artifact characteristics of four acoustic coupling materials — conventional ultrasound gel, HydroAid®, Aquaflex®, and Bolx-II® — under identical imaging conditions. Three ex vivo tissue samples (beef rump, pork loin, pork tenderloin) were scanned under four coupling conditions: conventional ultrasound gel, HydroAid®, Aquaflex®, and Bolx-II®, all pad-type materials standardized to 1 cm stand off thickness, using a linear transducer at 12 MHz. Acoustic Coupling Homogeneity Index (ACHI), Contrast-to-Noise Ratio (CNR), and High-Echo Artifact Fraction (HEAF) were calculated from standardized regions of interest. Inter group differences were assessed using one way Analysis of Variance (ANOVA) or Kruskal–Wallis tests with post hoc correction. HydroAid® and Aquaflex® generally showed higher ACHI and CNR than Bolx-II® across all tissue samples (all p < 0.001). However, HydroAid® generated the highest HEAF in all samples (up to 42.55 % ± 6.77 %), while conventional gel and Bolx-II® remained near zero, indicating that coupling efficiency and near field artifact generation are independent material properties. Aquaflex® provided the most favorable balance between image quality and near field artifact suppression, suggesting its suitability as a pad-type coupling material for superficial ultrasound examinations.

Keywords

Pad-type coupling material

Acoustic Coupling Homogeneity Index (ACHI)

High-Echo Artifact Fraction (HEAF)

Contrast-to-Noise Ratio (CNR)

Superficial ultrasound imaging

본 연구는 일반 초음파 겔, HydroAid®, Aquaflex®, Bolx-II®의 네 가지 패드형 초음파 전달 매질의 초음파 영상 품질과 근거리 고에코 허상 특성을 정량적으로 비교하고자 하였다. 소 우둔, 돼지 등심, 돼지 안심의 세 가지 ex vivo 생체 조직 시료를 대상으로, 일반 초음파 겔, HydroAid®, Aquaflex®, Bolx-II®의 네 가지 전달 매질 조건에서 B mode 초음파 영상을 획득하였으며, 패드형 전달 매질은 모두 1 cm 두께로 표준화하였다. 12 MHz 선형 탐촉자를 이용하여 영상을 획득하였으며, 표준화된 관심 영역에서 음향 결합 균질성 지수(Acoustic Coupling Homogeneity Index, ACHI), 대조도대잡음비(Contrast-to-Noise Ratio, CNR), 고에코 허상 비율(High-Echo Artifact Fraction, HEAF)을 산출하였다. 군 간 차이는 일원 분산분석(Analysis of Variance, ANOVA) 또는 크루스칼 왈리스 검정과 사후검정을 이용하여 분석하였다. HydroAid®와 Aquaflex®는 모든 조직 시료에서 Bolx-II®보다 유의하게 높은 ACHI 및 CNR 값을 보였다(p < 0.001). 그러나 HydroAid®는 모든 시료에서 가장 높은 HEAF를 나타냈으며, 최대값은 돼지 등심 시료에서 42.55 % ± 6.77 %였다. 반면 일반 초음파 겔과 Bolx-II®의 HEAF는 거의 0에 가까운 수준을 유지하였다. 이는 음향 결합 효율과 근거리 허상 발생이 서로 독립적인 재료 특성임을 시사한다. Aquaflex®는 영상 품질과 근거리 고에코 허상 억제 측면에서 가장 균형 잡힌 특성을 보여, 표재성 초음파 검사에서 활용 가능한 패드형 전달 매질로서의 유용성이 기대된다.

키워드

패드형 초음파 전달 매질

음향 결합 균질성 지수(Acoustic Coupling Homogeneity Index, ACHI)

고에코 허상 비율(High-Echo Artifact Fraction, HEAF)

대조도대잡음비(Contrast-to-Noise Ratio, CNR)

표재성 초음파 영상

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Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 45
No :3
Pages :240-246
Received Date : 2026-04-28
Accepted Date : 2026-05-18
DOI :https://doi.org/10.7776/ASK.2026.45.3.240

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

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