Neurotoxicity Associated with Radiological Contrast Agents Used during Coronary Angiography: A Systematic Review

Abstract

Contrast media enhances the visualization of the anatomic structures in radiological studies, allowing internal tissues such as blood vessels, kidney, ureters, adrenals and other organs to be identified. The evolution of contrast media highlights the efforts to develop less toxic chemical agents that possess low viscosity and osmolality. However, adverse effects such as idiosyncratic reactions, and organ specific damage are well characterized. Neurotoxicity, an important and dose related effect, appears to be due to disruption of the blood-brain-barrier by the high osmolarity of the contrast agent. From devastating cortical blindness to paralysis and seizures, an array of neurological manifestations has been described. In this systematic review, we describe the contrast-induced neurologic injury following coronary angiography and discuss the proposed mechanisms of injury leading to neurotoxicity.

Contrast-Induced Transient Neurological Symptoms Following Percutaneous Coronary Intervention: A Case Report

“…It is hypothetically correct that Iohexol has a low risk for CINI as it is a nonionic contrast agent with a relatively low or iso-osmolarity feature. Kariyanna et al stated that cerebral contrast retention has been reported with all types of contrast agents, regardless of their osmolality or ionic features, there is no clear association between the contrast dose and CINI, and most of the events occur with administration of 100 ml or more of the contrast agent, similar to our case [ 4 ].…”

“…Overall, complete clinical and radiological recovery of CINI have been reported with supportive management, including adequate hydration and close observation. In most of the reported cases [ 4 ], as in our patient, rapid recovery occurs within days. Considering the impaired renal function and CINI, we considered hemodialysis for rapid contrast clearance.…”

“…Focal neurological symptoms are uncommon and have been reported in only 5 cases [ 12 – 16 ]. Neurological events usually develop within 2 to 12 h of coronary angiography and mostly improve in 24 to 72 h [ 4 ]. Table 1 summarizes the reported cases in the literature of transient focal neurological symptoms following PCI.…”

“…The frequency of neurologic complications after cardiac catheterization has been reported to range from 0.03% to 0.3% for diagnostic procedures and from 0.3% to 0.4% for therapeutic procedures [ 1 – 3 ]. CINI is a rare complication of coronary angiography, with few reported cases [ 4 ]. Clinical symptoms may vary from an altered level of consciousness and cortical blindness to seizures and focal neurological symptoms [ 4 ].…”

“…CINI is a rare complication of coronary angiography, with few reported cases [ 4 ]. Clinical symptoms may vary from an altered level of consciousness and cortical blindness to seizures and focal neurological symptoms [ 4 ]. Neuroimaging is an important tool that has helped physicians to diagnose contrast retention and to exclude ischemic or hemorrhagic complications of PCI [ 5 ].…”