Background: Contrast-induced neurotoxicity (CIN) is a very rare complication of coronary angiography. Clinical presentations include encephalopathy, seizures, cortical blindness, and focal neurological deficits. An inherent difficulty in understanding the natural history of the condition as well as its risk factors and prognosis is the rarity of its occurrence. To date, there are only case reports published on this complication.
Patients and methods: This was a retrospective analysis of 9 patients with CIN (8 men, 1 woman; mean age, 64.6 ± 7.8 years; range, 47-72 years) and coronary artery disease who were administered iopromide contrast agent.
Results: In the last 3 years, we diagnosed 9 patients with CIN. Of these, 8 patients (89 %) had hypertension. The clinical presentations of the patients were different on admission: 6 patients had acute coronary syndrome and 3 patients had stable angina pectoris. One patient had history of previous contrast agent exposure. All patients underwent coronary angiography with a low-osmolar nonionic monomer contrast agent (iopromide; Ultravist®-300, Bayer Healthcare). The mean volume of contrast injected was 177 ± 58 ml. The mean time between contrast agent administration and clinical symptoms was 100 ± 71 min (range, 30-240 min). While in 5 of the patients (56 %) the clinical sign of CIN was confusion, 2 had ophthalmoplegia, 1 had cerebellar dysfunction, and 1 had monoplegia. In 8 of 9 patients (89 %), neurological symptoms resolved after giving supportive medication and hydration. Only 1 female patient, who had bilateral ophthalmoplegia, did not recover. Neurological recovery occurred at a mean time of 14.2 ± 6.7 h (range, 8-30 h).
Conclusion: CIN is a very rare condition. Advanced age, male gender, and hypertension are the greatest risk factors for CIN. Although the prognosis of CIN is benign, it can potentially cause permanent neurological deficits or death. We found that patients with ophthalmic involvement had a higher propensity for persistent deficit. On the basis of the current data, we propose 170 ml as the maximal recommended dose for coronary procedures.