Colour-coded density-gradients stone mapping: A novel reporting system for stone density on non-contrast computed tomography and its clinical applications. Issue 4 (1st October 2020)

• Record Type: Journal Article
• Authors: Adel Atta, Mohamed; Abdeldaeim, Hussein Mamdouh; Hashad, Mohamed Mohie Eldin; Shabaan, Mohamed Samir
• Is Part Of: Arab journal of urology. Volume 18:Issue 4(2020)
• Page Start: 247
• Page End: 251
• Publication Date: 2020-10-01
• Subjects: Non-contrast CT -- colour coding -- density gradients -- stones; Urology -- Periodicals; Urology; Urologic Diseases; Urologic Surgical Procedures; Urogenital Neoplasms; Arabia; Periodicals; 616.6
• DOI: 10.1080/2090598X.2020.1784601
• Languages: English
• ISSNs: 2090-598X

Abstract

ABSTRACT: Objective: To presents a novel clinically oriented system to report stone attenuation on non-contrast computed tomography (NCCT) using colour-coded density-gradients stone mapping and its clinical applications. Patients and methods: This study was performed on 50 patients with 63 stones. All patients had a recent history of failed shockwave lithotripsy (SWL) or failed dissolution therapy by alkalinisation of urine for radiolucent stones. A multi-detector NCCT examination of the abdomen and pelvis was performed in all patients. The stones were isolated and displayed in 'Volume Rendering Technique' using four-colour encoding. Results: Eight patients with failed dissolution therapy for radiolucent stones showed an outer layer of >500 Hounsfield units (HU) or a heterogeneous composition. A total of 42 patients with failed SWL had mean attenuations of <1000 HU on NCCT. Subsequent colour-coded stone mapping showed a dense core in all stones (>1000 HU) that failed to be clearly demonstrated by the mean HU alone. Conclusion: The initial use of a colour-coded density-gradients stone mapping reporting system for stone density on NCCT is useful for explaining failure of SWL or failure of dissolution therapy for radiolucent stones in selected cases. Abbreviations : HU: Hounsfield units; MSD: mean stone density; NCCT: non-contrast computed tomography; PCNL: percutaneous nephrolithotomy; SWL: shockwave lithotripsy; VRT: Volume Rendering Technique