초음파 히스토그램의 내부 장기에 대한 임상적용을 알아보기 위하여 다주파수 탐촉자의 초음파기기를 이용하여 실험하였다. 9마리의 정상 비글견을 우측전복부의 간과 우측신장, 좌측전복부의 간, 비장과 신장를 검사하였다. 같은 깊이의 B-모드 영상으로 간, 신장의 피질, 비장, 그리고 각 신장의 피질과 수질의 수치를 비교하였다. 우측신장피질의 메아리발생치는 간에 비하여 유의적으로 $15{\%}$ 낮았다. 비장의 메아리발생치는 좌측신장피질보다 $23{\%}$ 높았으며, 간은 좌측 신장피질보다 $30{\%}$ 높았다. 각 신장의 피질과 수질의 비교에서는 피질이 우측과 좌측에서 각각 $47{\%}$와 $65{\%}$ 높게 나타났다(P<0.05). 우측신장피질과 간실질간의 메아리발생치 비율은 $0.86{pm}0.11$, 비장과 좌측신장간에는 $1.37{pm}0.47$, 간실질과 좌측신장피질간에는 $1.30{pm}0.19$이었으며, 이들 모두다 유의적인 차이가 있었다(p<0.05). 초음파 히스토그램은 간, 비장, 신장 같은 내장장기의 구조물의 초음파적 평가에서 정량적으로 평가하기에 단순하고 유용하고 실질적이다.
For the assessment of the clinical application of histogram on internal parenchymal organs, ultrasonography with a multi-frequency transducer was taken. We scanned in the region of right cranial abdomen for both liver and right kidney, and left cranial abdomen for liver, spleen and left kidney in 9 normal Beagle dogs. The data from histogram examined in a region of interest centered on each picture element of B-mode images at the same depth were compared among liver, renal cortex, spleen, cortex and medulla of each kidney. The right renal cortex showed significantly lower echogenicity than parenchyma of liver by $15{\%}$. Spleen was more echogenic than the cortex of the left kidney by $23{\%}$, and liver was more echogenic than the left renal cortex by $30{\%}$. Renal cortex was more echogenic than medulla by $47{\%}$ and $65{\%}$ on the right and left side, respectively (p<0.05). The mean (${pm}SD$) values calculated echogenicity were $46.2{pm}12.3;(95\%$ confidential interval (CI), 41.0 to 55.0) and $53.4{pm}12.1;(95\%$ CI, 47.0 to 55.1) in in the right renal cortex and liver parenchyma, $65.0{pm}11.8;(95\%$ CI, 57.9 to 71.0) and $51.0{pm}16.9;(95\%$ CI, 42.8 to 54.1) in splenic parenchyma and renal cortex. And the mean values calculated echogenicity were $65.0{pm}10.15;(95\%$ CI, 60.1 to 71.5) and $52.0{pm}9.4;(95$ CI, 43.8 to 60.3) in liver parenchyma and the left renal cortex, $54.5{pm}18.3;(95\%$ CI, 40.1 to 62.8) and $35.0{pm}16.2;(95\%$ CI, 24.2 to 43.6) in the left renal cortex and medulla. And the mean values calculated echogenicity were $55.0{pm}14.4;(95\%$ CI, 47.3 to 61.7) and $40.0{pm}13.2;(95\%$ CI, 34.3 to 46.7) in the right renal cortex and medulla, respectively. In addition, the echogenicity ratios were $0.86{pm}0.11$ between the right renal cortex and liver parenchyma, $1.37{pm}0.47$ between spleenic parenchyma and the left renal cortex, $1.30{pm}0.19$ between liver parenchyma and the left renal cortex. All the values measured showed significant different (p<0.05). Ultrasound histogram is simple, useful and feasible to evaluate the sonographic architecture of the internal organs such as liver, spleen and kidney, quantitatively.
