Arterial Spin Labeling Magnetic Resonance Imaging to Diagnose Contrast-Induced Vasospasm After Intracranial Stent Embolization

Contrast Medium-Induced Transient Cortical Blindness: A Systematic Review of the Literature

PURPOSE

To summarize identified risk factors, the most common clinical presentations, radiological and neurophysiological features, and proposed pathophysiological mechanisms of contrast medium-induced transient cortical blindness (TCB).

METHODS

A systematic search of PubMed, Cochrane Central Register of Controlled Trials, and clinicaltrials.gov was performed. A total of 115 patients from 2 retrospective cohort studies, 10 case series, and 52 case reports were included.

RESULTS

The available evidence suggests that TCB can manifest after both invasive and noninvasive contrast-enhanced procedures. The pathophysiology of TCB is unclear; however, the primary mechanism suggested involves the direct neurotoxic effect of the contrast medium. Ionic, nonionic, hyperosmolar, isoosmolar, and even ethiodized oil have been implicated. Imaging findings are nonspecific, and absent in about half of patients. Onset is within 30 minutes in about half of patients and resolves within 1 day in about half of patients, but delayed onset after a day and delayed resolution after a week may occur. Higher contrast medium dosage and its injection solely into the posterior circulation were the only risk factors identified in association with TCB.

CONCLUSIONS

TCB is a rare, idiopathic, and typically self-limited condition associated with direct posterior cerebral neurotoxicity of iodinated contrast media, and appears to be dose-dependent.

Contrast-medium injury of spinal cord after cerebral angiography using nonionic contrast agents: A case report and literature review

INTRODUCTION

Contrast-induced spinal cord injury (CIS) is an uncommon yet severe neurological complication following cerebral angiography. It can lead to dire consequences, including limb paralysis, respiratory distress, and even death.

PATIENT CONCERNS

After undergoing cerebral angiography, a 41-year-old male initially displayed symptoms of dizziness and blurred vision, which advanced into dysphoria and limb weakness within 3 hours. These initial symptoms diminished by the 12th hour. Yet, 18 hours following the procedure, the patient developed quadriplegia and paresthesia below the T5 level, even though his deep sensory functions persisted unaffected.

DIAGNOSIS

The magnetic resonance imaging and diffusion weighted imaging scans excluded the presence of cerebrovascular ischemia or subarachnoid hemorrhage. However, the magnetic resonance angiography displayed arterial vasospasms in both posterior cerebral arteries and the V4 segment of the right vertebral artery. The encephalopathy symptoms faded within 12 hours, suggesting a probable contrast-induced encephalopathy diagnosis. An magnetic resonance imaging on day 4 revealed an intensified signal in the spinal cord from C1 to T1. This finding supported the diagnosis of CIS.

INTERVENTIONS

Following treatment with mannitol, methylprednisolone, and nimodipine, the patient's contrast-induced encephalopathy symptoms resolved completely within 12 hours. With a 2-week regimen of aspirin, methylprednisolone, and rehabilitative training, the neurological symptoms from CIS showed steady improvement.

OUTCOMES

The symptoms and signs of CIS gradually improved after 2 weeks' treatment and rehabilitation program.

CONCLUSION

Given the grave outcomes of CIS, like limb paralysis, breathing difficulties, and even fatality, it is imperative to remain cautious about this complication, even with the use of modern, less harmful contrast agents.

Investigating Recovery After Subarachnoid Hemorrhage With the Imaging, Cognition and Outcome of Neuropsychological Functioning After Subarachnoid Hemorrhage (ICONS) Study: Protocol for a Longitudinal, Prospective Cohort Study

Background

A subarachnoid hemorrhage is a hemorrhage in the subarachnoid space that is often caused by the rupture of an aneurysm. Patients who survive a subarachnoid hemorrhage have a high risk of complications and a negative long-term outcome.

Objective

The aim of the Imaging, Cognition and Outcome of Neuropsychological functioning after Subarachnoid hemorrhage (ICONS) study is to investigate whether and to what extent deficits exist in multiple domains after subarachnoid hemorrhage, including cognition, emotion and behavior, and to investigate whether brain damage can be detected in patients with subarachnoid hemorrhage. We aim to determine which early measures of cognition, emotion and behavior, and brain damage in the subacute stage play a role in long-term recovery after subarachnoid hemorrhage. Recovery is defined as functioning at a societal participation level, with a focus on resuming and maintaining work, leisure activities, and social relationships over the long term.

Methods

The ICONS study is an observational, prospective, single-center cohort study. The study includes patients with subarachnoid hemorrhage admitted to the Neurosurgery Unit of the University Medical Centre Groningen in the Netherlands. The inclusion criteria include diagnosis of an aneurysmal subarachnoid hemorrhage or an angiographically negative subarachnoid hemorrhage, sufficient ability in the Dutch language, and age older than 18 years. Patients will undergo neuropsychological assessment and magnetic resonance imaging 6 months after the subarachnoid hemorrhage. Furthermore, patients will be asked to fill in questionnaires on multiple psychosocial measures and undergo a structured interview at 6 months, 1 year, and 2 years after the subarachnoid hemorrhage. The primary outcome measure of the ICONS study is societal participation 1 year after the subarachnoid hemorrhage, measured with the Dutch version of the Impact on Participation and Autonomy questionnaire.

Results

The study was launched in December 2019 and recruitment is expected to continue until June 2023. At the time of the acceptance of this paper, 76 patients and 69 healthy controls have been included. The first results are expected in early 2023.

Conclusions

The ICONS study is the first to collect and combine data after subarachnoid hemorrhage in a variety of domains, including cognition, emotion and behavior, and brain damage. The results will contribute to a more comprehensive understanding of the consequences of both aneurysmal subarachnoid hemorrhage and angiographically negative subarachnoid hemorrhage, which may ultimately optimize timely treatment for this patient group by setting realistic and attainable goals to improve daily functioning.

Trial Registration

Netherlands Trial Register NL7803; https://trialsearch.who.int/Trial2.aspx?TrialID=NL7803

International Registered Report Identifier (IRRID)

DERR1-10.2196/38190

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

RATIONALE

Contrast-induced encephalopathy (CIE) is a rare complication caused by administration of intravascular contrast media and characterized by acute reversible neurological disturbance. Most of the CIE cases are reported after arterial administration of contrast media such as during cerebral or coronary angiographies, yet only a few articles have reported CIE secondary to intravenous contrast. A case of CIE secondary to intravenous contrast administration is reported here.

PATIENT CONCERNS

A 68-year-old man was admitted to our hospital for contrast-enhanced chest computed-tomography (CT) examination due to suspected pulmonary nodules. After CT examination, the patient lost consciousness and experienced a cardiorespiratory arrest. An emergency plain brain CT was done immediately which showed abnormal cortical contrast enhancement and cerebral sulci hyperdensity.

DIAGNOSES

After excluding other differential diagnoses such as electrolytes imbalance, hypo/hyperglycemia, cardiogenic pathologies and other neurological emergencies such as cerebral hemorrhage, cerebral infarction, the final diagnosis of CIE was made.

INTERVENTIONS

The patient was admitted to the intensive care unit for further management. A series of supportive treatments were arranged.

OUTCOMES

Follow-up visits at the outpatient clinic showed no lasting neurological deficits.

LESSONS

CIE should be considered as 1 of the differential diagnoses for a patient with acute neurologic symptoms after iodinate contrast administration. Neuroradiological imaging examinations are essential to rule out other etiologies such as acute cerebral infarction or intracranial hemorrhage.

Contrast-induced neurotoxicity related to neurological endovascular procedures: a systematic review

Contrast-induced neurotoxicity (CIN) is an adverse reaction to contrast agents which can occur in the context of diagnostic and therapeutic neurological endovascular procedures. Our goal was to conduct a systematic review of patients reported in the literature diagnosed with CIN after neurological endovascular procedures. A systematic search of EMBASE and MEDLINE databases was conducted. Inclusion criteria were age ≥ 18 years; neurological endovascular procedure performed ≤ 24 h before ictus; new manifestations compatible with encephalic dysfunction; imaging performed < 7 days after ictus; exclusion of other causes and manifestations attributed to pre-existing conditions. Forty-eight patients were included, of which 60.4% were female and 60.4% had arterial hypertension; median age was 63 years. The most frequent procedure was diagnostic cerebral angiography (n = 24, 50.0%) and non-ionic contrast agents were more frequently used (n = 40, 83.3%). Twenty-six patients (54.2%) developed clinical manifestations compatible with CIN during or immediately after the procedure, and the most frequent manifestations were encephalopathy, cortical blindness and motor deficit. The most frequent imaging findings were cortical contrast enhancement on CT (n = 23/42), and cortical sulci effacement (n = 18/48). Most patients presented complete clinical recovery (89.6%) at a median time of 3 days. Among patients with neuroimaging changes who underwent follow-up, complete regression of the abnormalities was shown in 81.5% at a median time of 5 days. CIN is a rare adverse reaction in the context of neurological endovascular procedures. Recognition of clinical manifestations and typical imaging abnormalities, while excluding other causes, is essential for diagnosis.