MRI findings in a case of transient cortical blindness after cardiac catheterization

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.

Case Report: Transient cortical blindness following coronary angiography

Temporary blindness, also known as transient cortical blindness, is an uncommon impediment of contrast agent usage during angiography procedures. The occurrence of blindness after a cardiac catheterization procedure is rare and its pathophysiology remains largely speculative. The most probable mechanism seems to be contrast agent-related disruption of the blood–brain barrier, possibly initiated by several predisposing factors. This case reports a 52-year-old man with transient vision loss that occurred following coronary angiography. Brain magnetic resonance imaging (MRI) showed no acute pathology and his vision spontaneously returned within approximately 15 hours post-procedure without any requirement of specific therapy. Suggesting that transient cortical blindness may have occurred following coronary angiography which subsequently self-resolved.

Case Report and Literature Review on Low-Osmolar, Non-Ionic Iodine-Based Contrast-Induced Encephalopathy

Contrast-induced encephalopathy (CIE) is a rare complication following percutaneous carotid and coronary interventions, and important diagnostic radiological signs include brain edema and cortical enhancement. In this report, we detail a case of probable CIE in an 84-year-old woman following a normal diagnostic coronary angiography (CAG) that involved 20 mL of the low-osmolar, non-ionic monomeric, iodine-based contrast agent iopromide (Ultravist 370). The patient was unconscious and presented with hemiparesis, hemianopia, recurrent seizures, and cardiac and respiratory arrest within minutes to hours following the procedure. Non-contrast computed tomography (CT) of the head showed increased subarachnoid density, cortical enhancement, and brain edema in the right hemisphere. Three days of rehydration, reduction in cranial pressure, and treatment with an anticonvulsant and dexamethasone resulted in a gradual recovery with no neurological deficits. This case highlights that severe neurotoxic symptoms may occur in response to low doses of low-osmolar, non-ionic, monomeric contrast agents. This finding is of importance to interventional cardiologists for diagnostic considerations and development of treatment plans.

Contrast-induced encephalopathy mimicking total anterior circulation stroke: a case report and review of the literature

INTRODUCTION

Contrast-induced encephalopathy is a rare and usually reversible entity due to the administration of iodinated contrast. Clinical manifestations include cortical blindness, encephalopathy, seizures and focal neurological deficits.

METHODS

We report the case of a 56-year-old woman who developed global aphasia and right hemiplegia after a cerebral angiography performed for a subarachnoid haemorrhage. A prompt brain MRI resulted negative, while CT scan revealed left cerebral oedema with the cerebral sulci effacement. Complete recovery was observed in 10 days.

DISCUSSION

Diagnosis of contrast-induced encephalopathy requires a temporal correlation between neurological dysfunction and administration of iodinated contrast. Usually, the symptomatology is transient with a full recovery within 48-72 h. The most common symptom is cortical blindness, while other symptoms have been rarely reported. Only 20 cases previously reported global aphasia and/or hemiplegia or mimed anterior circulation strokes. Prompt brain neuroimaging is essential in order to exclude an alternative diagnosis that requires a distinct therapeutic approach.

Delayed Leukoencephalopathy: A Rare Complication after Coiling of Cerebral Aneurysms

BACKGROUND AND PURPOSE

Delayed leukoencephalopathy is a rare complication that occurs after endovascular coiling of cerebral aneurysms. We aimed to describe a clinical picture of delayed leukoencephalopathy and explore potential associations with procedural characteristics.

MATERIALS AND METHODS

We considered endovascular coiling procedures for cerebral aneurysms performed between January 2006 and December 2017 in our institution with follow-up MRIs. We used logistic regression models to estimate the ORs of delayed leukoencephalopathy for each procedural characteristic.

RESULTS

We reviewed 1754 endovascular coiling procedures of 1594 aneurysms. Sixteen of 1722 (0.9%) procedures demonstrated delayed leukoencephalopathy on follow-up FLAIR MR imaging examinations after a median period of 71.5 days (interquartile range, 30-101 days) in the form of high-signal changes in the white matter at locations remote from the coil mass. Seven patients had headaches or hemiparesis, and 9 patients were asymptomatic. All imaging-associated changes improved subsequently. We found indications suggesting an association between delayed leukoencephalopathy and the number of microcatheters used per procedure (P = .009), along with indications suggesting that these procedures required larger median volumes of contrast medium (225 versus 175 mL, OR = 5.5, P = .008) as well as a longer median fluoroscopy duration (123.6 versus 99.3 minutes, OR = 3.0, P = .06). Our data did not suggest that delayed leukoencephalopathy was associated with the number of coils (P = .57), microguidewires (P = .35), and guiding systems (P = .57).

CONCLUSIONS

Delayed leukoencephalopathy after coiling of cerebral aneurysms may have multiple etiologies such as foreign body emboli, contrast-induced encephalopathy, or hypersensitivity reaction to foreign bodies.

Contrast-Induced Encephalopathy Resulting From Use of Ioversol and Iopromide

BACKGROUND

Contrast-induced encephalopathy (CIE) is a rare disease, whose etiology and risk factors remain unclear and need investigation.

METHODS

We collected 7 CIE cases from 2646 patients injected with ioversol and 5 CIE cases from 526 patients injected with iopromide, all of whom underwent neurointervention surgery in our regional centers. The incidence of CIE, its characteristics, and risks were analyzed in both groups.

RESULTS

The overall incidence of CIE was 0.38%, specifically 0.95% and 0.26% in the iopromide and ioversol groups, respectively; the former incidence was significantly higher than the latter (P = 0.029). The risk of CIE with iopromide was 3.567 to 3.618 times higher than that with ioversol (single-factor analysis odds ratio [OR], 3.618; 95% confidence interval [CI], 1.144-11.443; P = 0.029; multifactor analysis OR, 3.567 (95% CI, 0.827-15.379); P = 0.088). Moreover, acute cerebral infarction was an independent risk factor for CIE (OR, 4.024; 95% CI, 1.137-14.236; P = 0.031). Contrast-induced encephalopathy could occur within 5 minutes after injecting contrast media. The CIE characteristics differed according to the medium. In the ioversol group, the most common characteristic was visual disorder (71.43%), whereas in the iopromide group, the most common characteristic was delirium (100%).

CONCLUSIONS

Compared with ioversol, iopromide appeared more likely to lead to CIE. Acute cerebral infarction was an independent risk factor for CIE. The earliest CIE onset was within 5 minutes after injecting contrast. The characteristics of CIE varied significantly for different contrast media.

Contrast Extravasation is Predictive of Poor Clinical Outcomes in Patients Undergoing Endovascular Therapy for Acute Ischemic Stroke in the Anterior Circulation

OBJECTIVE

To investigate whether contrast extravasation on dual-energy computed tomography (DECT) in patients with acute ischemic stroke (AIS) after endovascular therapy (EVT) are related to hemorrhagic transformation (HT) and poor short-term clinical outcomes.

METHODS

A retrospective analysis was conducted on AIS patients who underwent EVT at Xuanwu hospital between November 2016 and January 2019. DECT was performed on all patients within 24 hours after EVT. Baseline demographic and clinical data were analyzed between patients with and without contrast extravasation and between patients with HT and non-HT, good and poor outcomes at 3 months post-EVT.

RESULTS

A total of 166 patients were included in the study with 51 (30.7%) patients experiencing contrast extravasation. Compared to patients without contrast extravasation, patients with contrast extravasation had longer onset to reperfusion time (444.8 minutes versus 374.0 minutes, P = .044) and higher percentages of greater than 3 retriever passes (16.7% versus 31.4%, P = .030). Contrast extravasation was associated with higher risk of HT (P = .038), poor outcome after discharge (P = .030), and longer hospital stay (P = .034). Multivariate analysis showed that contrast extravasation occurrence was an independent factor for HT (OR = 2.150, 95% CI 1.060-4.360, P = .034) and poor short-term outcome (OR = 2.936; 95% CI 1.147-7.518, P = .025).

CONCLUSIONS

The presence of contrast extravasation within 24 hours of EVT may be associated with higher risks of HT and may be predictive of unfavorable functional outcomes in AIS patients.

An Unusual Cause of Posterior Reversible Encephalopathy Syndrome

Posterior reversible encephalopathy syndrome (PRES) is a clinical radiographic diagnosis of heterogeneous etiologies. The pathogenesis of PRES remains unclear, but may be related to impaired cerebral autoregulation and endothelial dysfunction. We present a case of intravascular nonionic contrast-induced PRES observed after cerebral angiography. The index patient was a follow-up case of large vertebrobasilar artery-dissecting aneurysm for which endovascular coiling was done 6 months back. She improved completely within a week. Contrast-induced PRES is a reversible benign condition, knowledge of which is crucial for appropriate management.

A Case Report of Transient Cortical Blindness After Angiography

INTRODUCTION

Transient cortical blindness (TCB) is a rare complication after angiography and is proposed to be related to contrast extravasation. We present the first case of TCB after angiography that was evaluated using serial arterial spin-labeling magnetic resonance perfusion (ASLMRP) and susceptibility-weighted imaging (SWI).

CASE REPORT

A 65-year-old woman with dyslipidemia who had been treated for left vertebral artery dissection 3 months previously presented with dizziness and right hemiparesis. Magnetic resonance imaging of the brain revealed suspected dissection of the V4 segment of the left vertebral artery. Cerebral angiography was performed using a total of 46 mL of nonionic contrast material. Approximately 3 hours after the procedure, the patient started complaining of a slight headache and nausea along with bilateral cortical blindness. The 6-hour ASLMRP and SWI of the brain, respectively, revealed hypoperfusion and increased oxygen extraction fraction in the bilateral occipital lobes. The patient gradually regained vision over the next 12 hours, and follow-up ASLMRP and SWI revealed normal perfusion and normal SWI findings, respectively.

CONCLUSIONS

Hypoperfusion on ASLMRP and increased oxygen extraction fraction on SWI results derived for a patient presenting with TCB were demonstrated. Thus, we hypothesize that endothelin-related vasoconstriction is a pathophysiologic mechanism for TCB. To the best of our knowledge, this report is the first to describe ASLMRP and SWI findings in TCB after angiography.

Diffuse Fluid-Attenuated Inversion Recovery Hyperintensity in Subarachnoid Space Following Cerebral Angiography and Intravenous Thrombolysis

OBJECTIVE

Transient cortical blindness (TCB) is a relatively rare but well-recognized complication following cardiovascular and cerebral angiography.

METHODS

A 68-year-old male developed TCB following cerebral angiography along with punctate diffusion lesion evident on emergent magnetic resonance imaging (MRI). The patient received intravenous tissue plasminogen activator (IV-tPA) for suspected stroke.

RESULTS

Follow-up MRI revealed diffuse hyperintensities in subarachnoid space in fluid-attenuated inversion recovery (FLAIR) sequence mostly in bilateral occipital lobes.

CONCLUSION

The finding on the FLAIR as described in this case is an indication of diffuse disruption of the blood-brain barrier perhaps secondary to cerebral angiography, high blood pressure, and IV-tPA. To the best of our knowledge, this is the first reported case of TCB with diffuse postcontrast FLAIR changes.

Cerebral contrast retention after difficult cardiac catheterization: Case report

Background:

We report a diagnostic dilemma in a rare case of cerebral contrast retention after difficult cardiac catheterization in an elderly patient loaded with prasugrel.

Summary:

Our case report describes a 77-year-old female with history of hypertension, diabetes, and dyslipidemia who presented to emergency department complaining of chest pain. Patient was found to have an inferior wall ST elevation myocardial infarction. The patient was loaded with aspirin and prasugrel and taken for emergent cardiac catheterization. Cardiac catheterization revealed two-vessel coronary artery disease with unsuccessful attempt of percutaneous intervention. Immediately after procedure, patient developed an episode of seizure. Emergent computed tomography scan of the brain revealed hyperdensity in the right frontoparietal region consistent with intracerebral bleed. Repeat computed tomography (24 h later) revealed substantial interval improvement of hyperdensity. Follow-up magnetic resonance imaging of the head was normal. Given the lack of magnetic resonance imaging changes, the rate of resolution on computed tomography without expected subacute changes, and the lack of neurologic findings, the initial hyperdensity seen on computed tomography of the brain was believed to be secondary to contrast leakage during cardiac catheterization as opposed to intracranial hemorrhage.

Neurologic complications of cardiac tests and procedures

Arterial or central venous vascular access is the cornerstone of invasive cardiac diagnosis, monitoring, and therapeutics. Although procedural safety has significantly improved with protocols perfected over decades of use, their prevalence renders even the uncommon neurologic complication clinically relevant. Serious peripheral nerve complications result from direct or indirect nerve injuries in the setting of a hematoma or compartment syndrome. Functional outcome is dependent upon prompt diagnosis and early treatment, so proceduralists should be aware of the relevant anatomy and early signs of nerve injury. Ischemic stroke is the most common central nervous system complication of diagnostic and therapeutic cardiac catheterization, and is presumed to be due to embolization of atherosclerotic plaque or thrombus dislodged during guiding catheter manipulation, platelet-fibrin thrombus that forms on the catheters, or air that appears during catheter flushing. Acute neurologic deterioration after thrombolysis for acute myocardial infarction should be presumed to be an intracranial hemorrhage until proven otherwise. The ideal angiography suite of the future is patientcentric and multipurpose, coordinating diagnostic and therapeutic strategies for multivascular disease, allowing for multispecialty collaboration, and, in the event of a neurologic complication of a cardiac procedure, facilitating the various treating physicians to converge efficiently upon the patient.

Cortical blindness after contrast-enhanced CT scan in a patient of sarcoidosis - Is it related to posterior reversible encephalopathy syndrome?

Transient cortical blindness (TCB) is a well known but rare complication of administration of contrast agent. In this case report, we present a 53-year-old woman who is a follow-up case of sarcoidosis and developed TCB with focal neurological symptoms following contrast-enhanced computed tomography scan. Magnetic resonance imaging revealed bilateral T2/Flair hyperintensities in parieto-occipital, high frontal, and cerebellar hemispheres with involvement of corpus callosum. Clinically and radiologically patient improved significantly in 4 days. The exact mechanism is still speculative and its possible relationship with posterior reversible encephalopathy syndrome is briefly discussed. The patient's symptoms were presumed to be exacerbated by presence of hypertension, underlying autoimmune disorder, sepsis, and high osmolality of contrast agent. Though there is no definite evidence to suggest that a certain treatment regimen improves the natural history of this disease but control of risk factors can possibly prevent this rare but devastating complication.

Persistent neurological deficit from iodinated contrast encephalopathy following intracranial aneurysm coiling. A case report and review of the literature

Neurotoxicity from iodinated contrast agents is a known but rare complication of angiography and neurovascular intervention. Neurotoxicity results from contrast penetrating the blood-brain barrier with resultant cerebral oedema and altered neuronal excitability. Clinical effects include encephalopathy, seizures, cortical blindness and focal neurological deficits. Contrast induced encephalopathy is extensively reported as a transient and reversible phenomenon. We describe a patient with a persistent motor deficit due to an encephalopathy from iodinated contrast media administered during cerebral aneurysm coiling. This observation and a review of the literature highlights that contrast-induced encephalopathy may not always have a benign outcome and can cause permanent deficits. This potential harmful effect should be recognised by the angiographer and the interventionalist.

Cortical Blindness and Retrograde Amnesia Following Cerebral Angiography Studied by Early Diffusion Weighted MR imaging. A Case Report

Cortical blindness is a well described neuro-ophthalmologic complication of angiography due to neurotoxicity following contrast media exposure. A rarer association with retrograde amnesia has also been reported. Since ischemic stroke due to embolism remains the most common aetiology of neurological complications of diagnostic and therapeutic arterial catheterisation, prompt identification of the mechanism responsible for the clinical symptoms is essential for patient management. Although CT and conventional MRI findings have been reported in this condition, experience with diffusion weighted (DW) sequences is lacking especially in cases associated with memory impairment. A 65-year-old man with tinnitus underwent cerebral angiography for suspicion of a dural arteriovenous fistula. During the procedure the patient developed complete loss of vision and rapidly became confused. Brain CT showed bilateral cortical enhancement in the occipital lobes. MR with DWI was performed 3.5 hours after angiography. Early DWI showed no signal abnormalities thereby excluding an ischaemic complication. Gradual improvement of visual function occurred over the next 24 hours. After 48 hours the patient was alert and orientated but profound retrograde amnesia persisted with no memory for the events of the day of angiography. CT follow-up at one year was normal. DWI is invaluable in the evaluation of patients with cortical blindness with or without memory deficits precipitated by angiography and may advance understanding of the pathophysiology. Diffusion-weighted MRI is crucial in differentiating neuro-ophthalmologic complications precipitated by intracortical contrast leakage after angiography from an ischaemic stroke needing a prompt and often invasive treatment.

Transient cortical blindness after coronary angiography

Transient cortical blindness is rarely encountered after angiography of native coronary arteries or bypass grafts. This paper reports a case of transient cortical blindness that occurred 72 h after coronary angiography in a 56-year old patient. This was the patient's fourth exposure to contrast medium. Neurological examination demonstrated cortical blindness and the absence of any focal neurological deficit. A non-contrast-enhanced computed tomographic scan of the brain revealed bilateral contrast enhancement in the occipital lobes and no evidence of cerebral haemorrhage, and magnetic resonance imaging of the brain showed no pathology. Sight returned spontaneously within 4 days and his vision gradually improved. A search of the current literature for reported cases of transient cortical blindness suggested that this is a rarely encountered complication of coronary angiography.

The conundrum of transient cortical blindness following coronary angiography

We report a case of transient cortical blindness that occurred after coronary angiography and angioplasty performed through the right radial artery. This is a very rare entity, the physiopathology of which remains largely speculative. The most likely mechanism appears to be the local disruption of the blood-brain barrier by the contrast agent, possibly favoured by predisposing factors, which may cause a direct neurotoxic effect. All contrast agents can be associated with this complication, which does not seem to be volume dependent. The outcome is generally favourable, with spontaneous return of sight within 24-48 h and no requirement for specific therapy. Recurrence has never been reported.

Focal seizure and cerebral contrast retention after cardiac catheterization

Although rare, ionic and nonionic contrast-induced seizures occur as a complication of enhanced cranial computed tomography for both adults and children. However, contrast-induced seizures after cardiac catheterization has only been reported in adults. This report describes an 18-month-old male who developed a new-onset focal seizure 12 hours after cardiac catheterization. Unenhanced cranial computed tomography 1 hour after the seizure demonstrated general cerebral edema and unilateral focal cerebral contrast retention with sparing of the area supplied by the middle cerebral artery. The contrast was reabsorbed from the subarachnoid space over a 48-hour period, the cerebral edema resolved over several days, and the child returned to his baseline state 4 days after the seizure episode. This study documents the evolution of computed tomographic findings after contrast-induced seizures in a child. Contrast toxicity should be considered in any case of a new-onset neurologic deficit arising after angiography or enhanced computed tomography.

Implications of post-gadolinium MRI results in 13 cases with posterior reversible encephalopathy syndrome

BACKGROUND

There is a relative lack of definitive information about the contrast-enhancement characteristics of lesions in posterior reversible encephalopathy syndrome (PRES).

OBJECTIVE

Evaluation of contrast-enhanced MRI findings in PRES with a special emphasis on pathophysiology of post-gadolinium behavior of these lesions.

MATERIALS AND METHODS

Contrast-enhanced 1.5 T MRI findings and relevant clinical data of the patients were retrospectively reviewed on 13 cases (six males, seven females; age range: 22-78; mean age 47). Although fluid attenuated inversion recovery (FLAIR) and diffusion-weighted MR images were considered for identification of the entity, primarily post-contrast T1-weighted MR images were searched for traces of enhancement in the lesions.

RESULTS

No definitely enhancing lesion was identified in the MR images obtained in 6-48 h after onset of symptoms (mostly headaches, seizures and cortical visual field deficits) in this series. Severity of disease indicated by small hemorrhages, confluence of lesions or progression to cytotoxic edema did not seem to alter this result. Typical lesion characteristics were consistent with vasogenic edema on FLAIR and diffusion MR images. Acute elevation of blood pressure on chronic hypertensive background was responsible in four, eclampsia in three, uremia with blood pressure fluctuations in three, and cyclosporine-toxicity in three cases.

CONCLUSION

Although occasional enhancing brain lesions have been reported in the literature on PRES, contrast-enhancement of lesions may be a factor of scan timing and underlying etiology. Prospective studies with larger series on PRES are required for better evaluation of contrast-enhancement in MRI with respect to scan timing, which in turn may help understand its pathophysiology better.