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Published on: September 22, 2023
Colour-coded density-gradients stone mapping: A novel reporting system for stone density on non-contrast computed
Mohamed Adel Atta1, Hussein Mamdouh Abdeldaeim1, Mohamed Mohie Eldin Hashad1
1Faculty of Medicine, Alexandria University, Alexandria, Egypt.
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.
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