Konjenital Üriner Sistem Anomalilerinde Görüntüleme
Özet
Üriner sistem anomalileri, çocukluk çağında basit varyantlardan son dönem böbrek hastalığına yol açabilen ciddi klinik tablolara kadar uzanan, sık karşılaşılan doğumsal bozukluklardır. Teşhis ve takip süreçlerinde görüntüleme yöntemleri kritik önem taşımaktadır. Radyasyon içermemesi ve kontrast madde gerektirmemesi nedeniyle ultrasonografi (USG), pediatrik üriner sistemin öncelikli ve ilk tercih edilen görüntüleme yöntemidir. USG; renal agenezi, çift toplayıcı sistem, at nalı böbrek, kistik böbrek hastalıkları ve darlıklar gibi birçok anomalinin saptanmasında ve üriner dilatasyonun sınıflandırılmasında etkinlikle kullanılır. İkinci sırada tercih edilen manyetik rezonans görüntüleme (MRG) ise yüksek doku çözünürlüğü ve radyasyonsuz yapısıyla karmaşık anomalileri, böbrek fonksiyonlarını ve toplayıcı sistem yapılarını detaylıca ortaya koyar. Bilgisayarlı tomografi (BT) radyasyon ve nefrotoksisite riskleri nedeniyle çocuklarda oldukça kısıtlı bir kullanıma sahiptir. İşeme sistoüretrografisi (İSUG) ise mesane kateterizasyonu eşliğinde kontrast madde kullanılarak özellikle vezikoüreteral reflü ve üretral patolojilerin derecelendirilmesinde sıklıkla başvurulan floroskopik bir yöntemdir. Sonuç olarak, şüpheli olgularda USG ile başlanan süreç, elde edilen bulgular doğrultusunda diğer ileri görüntüleme yöntemlerinin seçimine başarıyla rehberlik etmektedir.
Urinary system anomalies are common congenital disorders in childhood, ranging from simple variants to severe clinical conditions that can lead to end-stage renal disease. Imaging methods play a critical role in the diagnosis and follow-up processes. Due to its lack of radiation and no requirement for contrast media, ultrasonography (USG) is the primary and first-choice imaging modality for the pediatric urinary system. USG is effectively used to detect many anomalies such as renal agenesis, duplex collecting system, horseshoe kidney, cystic kidney diseases, and obstructions, as well as to classify urinary dilatation. Magnetic resonance imaging (MRI), preferred as the second-line modality, details complex anomalies, renal functions, and collecting system structures with high tissue resolution and a radiation-free nature. Computed tomography (CT) has highly limited pediatric use due to radiation and nephrotoxicity risks. Voiding cystourethrography (VCUG) is a fluoroscopic method frequently performed with contrast media after bladder catheterization, specifically to grade vesicoureteral reflux and urethral pathologies. Consequently, the process starting with USG in suspected cases successfully guides the selection of subsequent advanced imaging modalities based on the findings.
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