4. Image acquisition • Neuroendocrine tumours imaging: whole body anterior and posterior scintigraphy images and/or relevant spot images and/or SPECT images may be performed 24 hours after the MIBG (123I) administration. These scans are eventually repeated after 48 hours.
• Myocardial imaging: anterior planar imaging of the chest at 15 min (early image) and 4 hours (late image) following administration of MIBG (123I) eventually followed by a single photon emission computed tomography (SPECT). 1. 4 Special warnings and precautions for use Potential for hypersensitivity or anaphylactic reactions If hypersensitivity or anaphylactic reactions occur, the administration of the medicinal product must be discontinued immediately and intravenous treatment initiated, if necessary.
To enable immediate action in emergencies, the necessary medicinal products and equipment such as endotracheal tube and ventilator must be immediately available. Individual benefit/risk justification For each patient, the radiation exposure must be justifiable by the likely benefit.
The activity administered should in every case be as low as reasonably achievable to obtain the required diagnostic information. Patients with sympathetic nervous system impairment In patients suffering from clinical conditions that influence the nervous or sympathetic system functioning, such as Parkinsonian syndromes, a decrease in MIBG (123I) cardiac uptake can be observed regardless of cardiac pathology.
Renal impairment Careful consideration of the benefit risk ratio in these patients is required since an increased radiation exposure is possible. Severe renal insufficiency may cause impaired imaging results since iobenguane (123I) is excreted mainly via the kidneys.
2. Careful consideration of the indication is required since the effective dose per MBq is higher than in adults (see section 11). 5). - To minimize radiation dose to the thyroid gland, thyroid uptake of free iodide should be prevented using stable iodine administered orally: • In adults, thyroid blockade should be performed approximatively 1 hour before MIBG (123I) injection, by a single administration of potassium iodide (130 mg) or potassium iodate (170 mg) (see Table 1 below).
• In adolescents, children and infants, thyroid blockade should be performed by administration of potassium iodide or potassium iodate, approximately 1 hour before MIBG (123I) injection, in the evening of the day of injection and the following day (in total, 3 intakes in 2 days).