Assesment of Criteria in Differentiation of Ureteral Stones from Phleboliths with Thin-Slice Unenhanced Computed Tomography

Abstract

Objective: The purpose of this study was to asses the accuracy of criteria in distinguishing distal urinary stones from phleboliths defined in the literature with thin-slice unenhanced helical computed tomography (CT). Materials and Methods: Between October 2004 and April 2005, we performed 3 cm length thin-slice (2 mm section thickness, pitch:1) helical CT on 31 patients with urinary stones and on 43 patients with 80 phleboliths. The size, shape, central lucency, soft tissue rim sign, comet-tail sign, density values and profile analysis of each calcification were recorded. Results: Fifty two (65%) of 80 phleboliths were round and 28 (35%) were oval shape. On the contrary, ten (32%) of 31 stone were round, 8 (26%) of them were of oval shape. Geometric configuration was seen in thirteen (42%) stones but not in any phleboliths. Mean densities of phleboliths and stones were 386,5 HU (131 HU/935 HU) and 1088 HU (526 - 1594), respectively. This difference was statistically significant (p

Keywords

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Üreter Taşları ile Flebolitlerin İnce kesit Kontrastsız Bilgisayarlı Tomografi ile Ayırtedilmesinde Kullanılan Kriterlerin Değerlendirilmesi

Öz

Amaç: Bu çalışmanın amacı kontrastsız helikal bilgisayarlı tomografide üreter taşları ile flebolitleri ayırtetmek için daha önce literatürde tanımlanmış olan kriterlerin yeterliliğini değerlendirmektir. Gereç ve Yöntemler: Altı aylık zaman periyodunda taşı olan 31 hastaya ve toplam 80 fleboliti olan 43 hastaya 3 cm uzunluğunda ince kesit (kesit kalınlığı: 2 mm, pitch: 1) olmak üzere kontrastsız helikal BT çekimi yapıldı. Her kalsifikasyonun boyut, şekil, santral lüsensi, yumuşak doku halka işareti, kuyruklu yıldız işareti, densite değerleri ve profil analizi kaydedildi. Bulgular: Flebolitlerin 52'si (%65) yuvarlak, 28'i oval (%35) şekilliydi. Taşların ise 10'u (%32) yuvarlak, 8'i (%26) oval şekilliydi. Taşların 13'ü (%42) geometrik şekilli iken hiçbir flebolit geometrik şekilli değildi. Flebolit ve taşların ortalama densite değerleri sırasıyla 386,5 HU (131 HU/935 HU) ve 1088 HU (526 HU - 1594 HU) ölçülmüş olup bu değerler arasındaki fark istatistiksel olarak anlamlı idi (p

Anahtar Kelimeler

• Bilgisayarlı tomografi, üreter taşı, flebolit

Kaynakça

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