The value of computed tomography in determining the percentage of hepatosteatosis: An experimental animal study

Öz

Background and Aims:To analyze the degree of hepatosteatosis and computed tomography findings experimentally using the mouse liver to create computed tomography indexes for determining the degree of hepatosteatosis of the donor liver. Materials and Methods:Forty Swiss Albino mice were obtained. Whole body computed tomography scans were obtained by Picker MxTwin four-slice multidetector computed tomography device. To induce hepatosteatosis, the mice were fed by oral gavage with 0,06 mL CCl 4 plus 0,04 mL corn oil, totally 0,1 mL, in 2500 mg/kg/day CCl4 dosages. The study was continued for four weeks. The computed tomography density measurements were obtained by taking the average of three different 0,5 cm 2 areas in every organ. Data were compared with pathology. The livers, spleens, kidneys, and paravertebral muscles of the mice were removed. Five-micron thick slices from the paraffin blocks were mounted to slides. An interactive image analysis system (Aequitas, Dynamic Data Links) was used to measure the degree of steatosis in the liver specimens. For each specimen, the proportion of liver with steatosis was determined. Results were assessed statistically. Results:A reduction of 40 Hounsfield units in liver density indicates 30% hepatosteatosis. There was a statistically significant correlation between the liver/spleen, liver/kidney and liver/ muscle ratios and the histomorphometric hepatosteatosis percentage. When the liver/spleen ratio is ≤0,32, the critical value for the transplantation of ≥30% hepatosteatosis must be doubted. Conclusions:With the measurement of the liver/spleen ratio, the total hepatosteatosis percentage can be calculated according to a formula, which we introduce herein, based on our experimental study.

Anahtar Kelimeler

• Liver transplantation, fatty liver, multidetector computed tomography, experimental animal use, complications

Karaciğer yağlanmasının yüzdesinin tespit edilmesinde bilgisayarlı tomografinin önemi: Deneysel hayvan çalışması

Öz

Giriş ve Amaç:Verici karaciğerinin yağlanma derecesinin tespit edilmesi için fare karaciğerlerini kullanmak suretiyle bilgisayarlı tomografi indeksleri oluşturarak deneysel olarak yağlanma derecesinin ve bilgisayarlı tomografi bulgularının analizi. Gereç ve Yöntem:Kırk adet Swiss Albino fare elde edildi. Picker MxTwin marka 4 kesitli multidedektör bilgisayarlı tomografi cihazı kullanılarak farelerin tüm vücut tomografik incelemeleri sağlandı. Fareler 0,06 mL CCl 4 M ve buna ek olarak 0,04 mL mısırözü yağı ile toplam 0,1 mL olacak şekilde 2500 mg/kg/gün CCl4 C dozunda oral gavaj ile beslendi ve karaciğer yağlanması oluşturulmaya çalışıldı. Çalışma 4 hafta sürdü. Bilgisayarlı tomografi dansite ölçümleri, her organdan alınan farklı üç 0,5 cm 2 'lik alanın ortalaması alınarak elde edildi. Veriler patoloji ile karşılaştırıldı. Farelerin karaciğerleri, dalakları, böbrekleri, paravertebral kasları çıkarıldı. Parafin bloklardan elde edilen 5 mikron kalınlığındaki kesitler lama aktarıldı. Karaciğer örneklerindeki yağlanma miktarının ölçümü için interaktif imaj analiz sistemi (Aequitas, Dynamic Data Links) kullanıldı. Her örnek için karaciğer yağlanma oranı belirlendi. Sonuçlar istatistiksel olarak değerlendirildi. Bulgular: Karaciğer dansitesindeki 40 Hounsfield ünitelik azalma %30'luk karaci-ğer yağlanmasına denk gelmektedir. Karaciğer/dalak, karaciğer/böbrek ve karaciğer/kas dansite değerleri ile histomorfometrik karaciğeryağ-lanması oranı arasında istatistiksel olarak anlamlı bir korelasyon vardı. Karaciğer/dalak bilgisayarlı tomografi dansite oranı 0,32 ve altında olduğunda, transplantasyonda karaciğer yağlanması için kritik değer olan %30 ve üzeri değerden şüphelenilmelidir. Sonuç:Bu deneysel çalışmada ortaya koyduğumuz formülle, karaciğer/dalak dansite oranı ölçümü ile total karaciğer yağlanması hesaplanabilir.

Anahtar Kelimeler

• Karaciğer transplantasyonu, yağlı karaciğer, multidedektör bilgisayarlı tomografi, deneysel hayvan kullanımı, komplikasyonlar

Kaynakça

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