Diascan

Diascan is indicated as a contrast medium for cranial and spinal resonance imaging (MRI) and for general MRI of the body after intravenous administration. Diascan provides contrast enhancement and facilitates visualisation of abnormal structures or lesions in various parts of the body including the CNS.

No special preparation of the patient is required. Gadodiamide should be drawn into the syringe immediately before use. The vial is intended for one patient only. Contrast medium not used in one examination must be discarded.
Dosage for adults and children
: The recommended dosage is 0.1 mmol/kg body weight (equivalent to 0.2 ml/kg body weight) up to 100 kg. Above 100 kg body weight 20 ml is usually sufficient to provide diagnostically adequate contrast. The required dose should be administered as a single intravenous injection. To ensure complete injection of the contrast medium, the intravenous line may be flushed with 5 ml sodium chloride injection 0.9%.
Adults only
: When brain metastases are suspected, a dosage of 0.3 mmol/kg body weight (equivalent to 0.6 ml/ kg body weight) can be administered up to 100 kg. Above 100 kg body weight a total of 60 ml is usually sufficient. The dose of 0.3 mmol/kg body weight can be administered as a bolus intravenous injection. In patients with equivocal scans after administration of the 0.1 mmol/kg body weight injection, a second bolus injection of 0.2 mmol/kg body weight (equivalent to 0.4 ml/kg body weight) may be of additional diagnostic value when administered within 20 minutes of the first injection.

Discomfort with a general sensation of warmth, coolness or a sensation of local pressure or pain at the injection site were commonly (>1% and <10%) observed in clinical studies. Dizziness, nausea, headache and a perverted sense of taste or smell were reported less frequently, but also in >1% of patients.

The accepted safety considerations and procedures that are required for magnetic resonance imaging are applicable when Diascan is used for contrast enhancement. Administration of contrast media should be performed by qualified personnel familiar with the procedure and an appropriate technique should be utilised. The possibility of a reaction, including serious, life-threatening, fatal, anaphylactoid or cardiovascular or other idiosyncratic reactions should always be considered, especially in those patients with known clinical hypersensitivity or a history of asthma or other allergic respiratory disorders. A course of action should therefore be planned in advance; with necessary drugs and equipment available for immediate treatment should a serious reaction occur. Transitory changes in serum iron (within the normal range in the majority of cases) have been observed in some patients after administration of Diascan. The clinical significance of this, if any, is not known but all patients in whom this effect was observed remained asymptomatic. Diascan interferes with serum calcium measurements with some colorimetric (complexometric) methods commonly used in hospitals. It may also interfere with determinations of other electrolytes (e.g. iron). Thus it is recommended that such methods not be used for 12-24 hours after administration of Diascan. If such measurements are necessary, the use of other methods is recommended. Diagnostic procedures involving the use of contrast agents should be conducted under supervision of a physician with the prerequisite training and a thorough knowledge of the procedure to be performed. If Diascan is drawn into a disposable syringe it should be used immediately. If non-disposable equipment is used, scrupulous care should be taken to prevent residual contamination with traces of cleansing agents.
Data on the safety of repeated injections are not available. If the physician determines sequential or repeat examinations are required, a suitable time interval between administrations should be observed to allow for clearance of the drug from the body. In some patients with severely impaired renal function (GFR<10 ml/min), further small reductions in GFR and increases in serum creatinine have been observed after administration of Diascan. Since the clinical relevance of these findings is not fully known, care should be exercised before using Diascan in such patients.

This is a clear, colourless to slightly yellow aqueous solution containing Gadodiamide USP 287 mg/ml equivalent  to 0.5 mmol/ml. For Magnetic resonance imaging, visualization of normal and pathological brain and spinal tissue depends, in part, on variations in the radiofrequency signal intensity. Gadodiamide decreases both the T1 and T2 relaxation times in tissues where it is distributed. At clinical doses, the effect is primarily on the T1 relaxation time, and produces an increase in signal intensity.