Cardiorespiratory arrest after iso-osmolar iodinated contrast injection: A case report of contrast-induced encephalopathy following contrast-enhanced computed-tomography

Contrast-induced encephalopathy with significantly elevated levels of cerebrospinal fluid protein

Contrast-induced encephalopathy (CIE) is a rare complication of angiography. According to our knowledge, the majority of CIE reports is imaging observations and rarely includes results of cerebrospinal fluid (CSF) tests. Furthermore, among the cases reporting the data for CSF testing, most of the results were normal. Here, we report a case of CIE presenting with significantly elevated levels of CSF protein. We found that the course of improvement in brain imaging findings was not consistent with the severity of clinical manifestations. The diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) sequences were normal. Considering the lack of convenient direct indicators to observe blood-brain barrier (BBB) function, changes in the levels of CSF protein may be related to BBB permeability and recovery and may serve as a potential prognostic marker.

Pathophysiology of Contrast-Induced Neurotoxicity: A Narrative Review of Possible Mechanisms

BACKGROUND

Contrast-induced neurotoxicity (CIN) is an increasingly observed event following the administration of iodinated contrast. It presents as a spectrum of neurological symptoms that closely mimic ischaemic stroke, however, CIN remains a poorly understood clinical phenomenon. An appreciation of the underlying pathophysiological mechanisms is essential to improve clinical understanding and enhance decision-making.

METHODS

A broad literature search of Medline (1946 to December 2022) and Embase (1947 to December 2022) was conducted. Articles discussing the pathophysiology of CIN were reviewed.

SUMMARY

The pathogenesis of CIN appears to be multifactorial. A key step is likely blood-brain barrier (BBB) breakdown due to factors including ischaemic stroke, uncontrolled hypertension, and possibly contrast agents themselves, among others. This is followed by passage of contrast agents across the BBB, leading to chemotoxic sequelae on neural tissue.

KEY MESSAGES

This review provides a clinically oriented review on the pathophysiology of CIN to enhance knowledge and improve decision-making among clinicians.

Flow diagram of the differential diagnosis and clinical decision making in a rare case of contrast-induced encephalopathy following cardiac catheterization: a case report

BACKGROUND

Contrast-induced encephalopathy (CIE) is considered as an uncommon complication following cardiac catheterization. Due to the varied manifestations, CIE has no formal diagnostic criteria. In fact, the incidence of CIE may be greatly underestimated because of the difficulty in its differential diagnosis with other cerebrovascular complications. Thus, making a flow diagram according to patients' clinical symptoms and examinations after cardiac catheterization to help clinicians diagnose CIE is important and needed.

CASE PRESENTATION

In this report, we describe a case of probable CIE in a 66-year-old Chinese man with hypertension who underwent cardiac catheterization with stents placement in the bifurcation lesion, during which 80 ml iopromide contrast was used. About 2 h following the procedure, the patient lost his consciousness suddenly and suffered from a status epilepticus. Malignant arrhythmias were not found through continuous electrocardiogram monitoring, but mild ST-segment elevation was displayed in leads I and aVL. The echocardiography, plasma glucose and electrolyte levels were normal. Emergency re-angiography with percutaneous transluminal coronary angioplasty was performed in the culprit lesion, which involved 60 ml iopromide contrast. However, the patient remained unconsciousness and epilepticus. Non-contrast computed tomography (CT) of the head showed cortical and subarachnoid enhancement as well as prolonged retention of contrast media in the middle cerebral artery. With supportive treatment of intravenous hydration, sedative and dehydrant, the patient recovered 3 h later and finally discharged without any neurological deficits.

CONCLUSIONS

CIE is an acute reversible encephalopathy induced by contrast media. It is exceptionally challenging to make the diagnosis of CIE following cardiac catheterization since there is a lack of consensus on the definition of CIE. Via this case we reviewed the related literatures, through which a flow diagram of the differential diagnosis and clinical decision making was given, which could help to differentiate CIE from other neurological complications following cardiac catheterization.

Radiological findings of contrast-induced encephalopathy following cerebral angiography: A case report

INTRODUCTION

Contrast-induced encephalopathy (CIE) is a rare complication associated with the use of contrast media. New contrast agents make contrast complications increasingly rare. The diagnosis of CIE is challenging, particularly in patients with acute ischemic stroke. Neuroimaging results for patients with CIE can also be highly variable.

PATIENT CONCERNS

A 63-year-old man with severe internal carotid artery stenosis who experienced several symptoms, including dizziness, nausea, vomiting, fever, and blurred vision after being administered the contrast agent iodixanol.

DIAGNOSES

Multiple CT and MRI brain scans were performed. After excluding other differential diagnoses such as electrolytes imbalance, hypo/hyperglycemia and other neurological emergencies such as cerebral hemorrhage, cerebral infarction, the final diagnosis of CIE was made.

INTERVENTION

Treatment consisted of adequate hydration, intravenous dexamethasone, mannitol, and anticonvulsants.

OUTCOME

The patient demonstrated progressive neurological improvement, and recovered from all symptoms on the fifth day. Follow-up at 3 months shows a good prognosis for patients.

CONCLUSION

Patients with CIE may have a high signal on diffusion-weighted imaging and a low signal on apparent diffusion coefficient brain MRI. This is similar to the MRI findings in acute stroke. This needs to be distinguished from acute cerebral infarction and suggests that we should closely monitor patients' neurological symptoms at the time of cerebral angiography and after the investigations.

Contrast-induced encephalopathy following endovascular treatment for intracranial aneurysms-risk factors analysis and clinical strategy

PURPOSE

Contrast-induced encephalopathy (CIE) was defined as new onset of neurological deficits after exposure to contrast media, which could be observed after the endovascular treatment for intracranial aneurysms.

METHODS

We enrolled a consecutive cohort of patients who underwent endovascular treatment for unruptured intracranial aneurysms. CIE was defined as a reversible neuropathic syndrome that occurred after interventional therapy, accompanied by imaging abnormalities and excluding other diseases. Multivariable Poisson regression analysis was performed to show risk factors by incidence rate ratio (IRR) and a clinical strategy was proposed.

RESULTS

Among the 579 patients who underwent interventional therapy for intracranial aneurysms, the crude incidence rate of CIE was 2.4% (95% CI, 1.2-3.6%) at our center. Headache, hemiplegia, and disorientation could be initial symptoms, and cortical blindness was the most common localized deficit. Cerebral edema and sulci effacement on CT were observed, and re-revaluation after treatments on CT/MRI showed absent lesions. The risk factors were history of stroke (IRR, 7.752; P = 0.007), history of hypertension (IRR, 1.064; P = 0.042), posterior circulation aneurysms (IRR, 9.412; P = 0.004) and higher dosage of contrast agents (IRR, 1.018; P = 0.007). After the strategy of accelerating excretion of contrast agents, reduction of intracranial pressure and anti-inflammation/vasospasm therapy, the prognosis was favorable with most patients fully recovered within 72 h.

CONCLUSION

History of stroke and posterior circulation aneurysms were main risk factors for CIE. A higher dosage of contrast agents might induce CIE, and the history of hypertension should be considered as well.

Contrast-induced encephalopathy and permanent neurological deficit following cerebral angiography: A case report and review of the literature

Contrast-induced encephalopathy (CIE) is an uncommon complication associated with contrast exposure during angiographic procedures that is usually transient but occasionally leads to permanent complications or death. Due to the low incidence of CIE, there are still insufficient reports. This study was used to summarize the clinical features of CIE through a case report and systematic review. We summarized and reviewed 127 patients with CIE, and we found that the total incidence of CIE between men and women had no difference (49.61 and 50.39%, respectively), but the average age in female patients with CIE was older than that in male patients (62.19 and 58.77 years, respectively). Interestingly, the incidence of female patients with CIE in the poor prognosis group was significantly higher than that in the good prognosis group (62.50 and 36.51%, respectively), and the average age of these female patients in the poor prognosis group was younger than that in the good prognosis group (61.39 and 62.82 years, respectively). The contrast medium types were mainly nonionic (79.69 and 73.02%, respectively) and low-osmolar (54.69 and 71.43%, respectively) in both groups. Importantly, the total contrast media administrated in patients with poor prognoses was greater than that administrated in patients with good prognoses (198.07 and 188.60 ml, respectively). In addition, comorbidities in both groups included hypertension (55.91%), diabetes mellitus (20.47%), previous contrast history (15.75%), renal impairment (11.81%), and hyperlipidemia (3.15%). The percentage of patients with cerebral angiography was significantly higher in the poor prognosis group than that in the good prognosis group (37.50 and 9.52%, respectively), whereas the percentage of patients with coronary angiography in both groups had the opposite results (35.94 and 77.78%, respectively). In conclusion, CIE may not always have a benign outcome and can cause permanent deficits. Female gender, younger age, the higher dose of contrast medium, and the procedure of cerebral angiography may be related to the patient's poor prognosis.