The challenges of radioiodine treatment for incontinent paediatric patients with complex care needs.

OBJECTIVE: A thyrotoxic paediatric patient with incontinence, autism and Down's syndrome was referred for radioiodine therapy. Here, the risk assessment methodology and measures taken to deliver a legally compliant treatment that was acceptable to the family are described. METHODS: Prior risk assessment indicated that the most active incontinence waste would require decay storage until it could be transported for disposal. The Health and Safety Executive (HSE) indicated that school staff would be occupationally exposed under the Ionising Radiations Regulations (2017) based on the patient's retained activity. To avoid the need for HSE registration, it was advised that the patient's return to school may need to be delayed slightly. Post-treatment, confirmatory waste and patient dose rate measurements were made to refine the advised time scales. RESULTS: Domestic waste disposal resumed at 28 days. The patient recommenced schooling a few days after their school reopened after the summer break. The school underwent HSE notification. CONCLUSION: Careful planning allowed us to provide a safe, compliant treatment regarding waste management and occupational exposure. ADVANCES IN KNOWLEDGE: Incontinent 131I outpatient treatments require detailed, patient specific waste management. The HSE considered school staff as occupationally exposed by the patient well after normal social restrictions had ended.

Hepatic selective internal radiation therapy: how well does pretreatment 99mTc-macroaggregated albumin activity distribution and quantification agree with post-therapy bremsstrahlung imaging?

AIM: The aim of this study was to examine the agreement of pretreatment Tc-macroaggregated albumin imaging performed for selective internal radiation therapy (SIRT) workup with Y percentage lung shunt (PLS) and regional hepatic distribution in subsequent post-therapy bremsstrahlung imaging. PATIENTS AND METHODS: Planar images were used to calculate PLS. The significant Y bremsstrahlung scatter required background correction. Results using both Y lung background regions of interest (ROI) reported in previous studies and extended ROIs (reflecting lung background variation) were compared with Tc-MAA PLS. Lesion and healthy liver volumes were outlined on diagnostic computed tomography scans and registered to Tc-MAA and Y single-photon emission computed tomography/computed tomographydata. Single-photon emission computed tomography voxel values were normalized to injected Y activity. Volume mean activities were calculated, and converted into the mean absorbed dose. Agreement was quantified using Bland-Altman analysis. RESULTS: PLS: The bias using previous studies' lung background ROIs was -10.71%, with a 95% confidence interval (CI) of -18.79 to -2.64%. The extended ROI yielded a bias of 0.77% (95% CI: -2.23 to 3.70%). Liver: The healthy liver bias was 0.01 MBq/ml (0.17 Gy), with a -0.05 to 0.06 MBq/ml (95% CI:0.80 -1.93 Gy). The lesion mean activity/ml bias was -0.02 MBq/ml (3.71 Gy), with a -0.81 to 0.76 MBq/ml (95% CI: -35.49 to 28.07 Gy). CONCLUSIONS: The PLS agreement was sensitive to the Y lung background correction ROI, potentially explaining a previously published controversy. The mean activity and absorbed dose agreement for the metastatic lesions was poorer than the healthy liver volumes studied here.