동적 컴퓨터단층촬영을 이용하여 연령에 따른 CT-GFR 수치에 대한 패턴을 살펴보기 위해 본 연구를 실시하였다. 품종이나 성별에 대한 제한 없이 다양한 연령으로 15마리의 개를 이용하였다. 혈액검사, 요검사, 영상학적 검사를 실시하여 개의 건강 상태를 확인한 후, propofol-isoflurane을 이용한 호흡마취를 실시하여 CT 촬영을 하였다. Iohexol (1 ml/kg, 300 mgI/ml)을 3 ml/s 일정한 속도로 2분간 주입하면서 1.5초 간격으로 총 80개의 영상을 촬영하여 파트락 분석을 통해 사구체여과율 (ml/min/kg)을 측정하였다. 양측 신장의 사구체여과율의 범위는 2.57-6.60 ml/min/kg이었다. 연구에서 연령에 따라 사구체여과율의 유의적인 차이는 확인되지 않았다.
The purpose of this study is to assess the relationship between glomerular filtration rate (GFR) and age by using dynamic computed tomography (CT) and Patlak plot analysis in dogs. Fifteen dogs were used in this study. CT-GFR study was performed under general anesthesia using propofol and isoflurane. 1 ml/kg dosage of 300 mgI/ml iohexol was administered at a rate of 3 ml/s during GFR measurement. CT-GFR was determined with a single-slice dynamic acquisition and Patlak plot analysis. The individual and global GFR values were calculated to plasma clearance per body weight (ml/min/kg). Bodyweight ($mean{pm}SD$) ranged from 2.0 to 5.7 kg ($3.31{pm}1.13$ kg). Age ranged from 3 years to 13 years old ($7.14{pm}3.30$). $Mean{pm}SD$ creatinine ($0.53{pm}0.34 $mg/dl), phosphorus ($4.1{pm}1.2$ mg/dL), and albumin ($3.3{pm}0.3$ mg/dL) concentrations and urine protein-to-creatinine ratios (all ratios were < 0.5) were within reference ranges. Abdominal ultrasonography revealed small-sized renal calculi, mineralization, or renal cyst at eight dogs. The global CT-GFR ranges shown in this study was 2.57 to 6.60 ml/min/kg. In this study, there was no trend toward weight-adjusted CT-GFR with increasing age. We found no relationships between age-related kidney dysfunction in fifteen dogs. Small-sized renal calculi or cysts did not affect renal function in this study. However, it is thought that a large sample size may have been required to document an age effect.
