Transient cortical blindness after coronary angiography

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.

Neuroradiological features of contrast-induced neurotoxicity: A systematic review and pooled analysis

BACKGROUND

Contrast-induced neurotoxicity (CIN), is an increasingly recognised complication of endovascular procedures, presenting as a spectrum of neurological symptoms that mimic ischaemic stroke. The diagnosis of CIN remains a clinical challenge, and stereotypical imaging findings are not established. This study was conducted to characterise the neuroimaging findings in patients with CIN, to raise diagnostic awareness and improve decision making.

METHODS

We performed a systematic review of PubMed and Embase databases from inception (1946/1947) to June 2023 for reports of CIN following administration of iodinated contrast media. Studies with a final diagnosis of CIN, which provided details of neuroimaging were included. All included cases were pooled and descriptive analysis was conducted.

RESULTS

A total of 84 patients were included, with a median age of 64 years. A large proportion of patients had normal imaging (CT 40.8 %, MRI 53.1 %). CT abnormalities included cortical/subarachnoid hyperattenuation (42.1 %), cerebral oedema/sulcal effacement (26.3 %), and loss of grey-white differentiation (7.9 %). Frequently reported MRI abnormalities included brain parenchymal MRI signal change (40.8 %) and cerebral oedema (12.2 %), most commonly observed on FLAIR sequences (26.5 %). Characterisation of imaging findings according to anatomical location and clinical symptoms has been conducted.

CONCLUSIONS

Neuroimaging is an essential part of the diagnostic workup of CIN. Analysis of the anatomical location and laterality of imaging abnormalities may suggest relationship between radiological features and actual clinical symptoms, although this remains to be confirmed with dedicated study. Radiological abnormalities, particularly CT, appear to be transient and reversible in most patients.

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.

Rare Cases of Contrast-Induced Encephalopathies

Cortical blindness (CB) due to contrast-induced encephalopathy is a rare complication in endovascular procedure. Although exact mechanism is not known, disruption of blood–brain barrier (BBB) by contrast agent is supposed to be caused. We report two cases of contrast-induced encephalopathies after coil embolization of unruptured aneurysm. A 68-year-old woman with unruptured basilar artery aneurysm was treated with endovascular stent-assisted coil embolization. The procedure was successfully accomplished within 172 min using about 160 ml of contrast medium (iopamidol). However, she manifested with CB 3 h after the procedure and seizure on the next day. Immediate computed tomography revealed the cortical enhancement in both occipital lobes. Diffusion-weighted imaging–magnetic resonance imaging and fluid-attenuated inversion recovery sequence 1 day after the procedure revealed edema in both occipital lobes with no findings of ischemia or hyperperfusion. Electroencephalography showed sharp and slow waves in both occipital lobes. She required endotracheal intubation on day 2 to maintain airways and breathing. Her sensorium improved 4 days after the procedure with administration of steroid and anticonvulsant. She was extubated on day 4 after the procedure. She was discharged with persisting CB as a sequel.

Irreversible fatal contrast-induced encephalopathy: a case report

Background

Contrast-induced encephalopathy (CIE) is a well-known complication of iodinated contrast agents during angiography and vascular interventions. It can manifest as hemiparesis, cortical blindness, speech changes, Parkinsonism, confusion, seizure, and coma. Most of the reported CIE cases have been transient and reversible. Irreversible fatal CIE cases have been rarely reported. All the fatal CIE cases reported involved the use of ionic high osmolar contrast agents. Here, we document a heretofore unreported fatal CIE after digital subtraction angiography (DSA) using iopamidol, which is a type of non-ionic monomer low osmolar contrast agent.

Case presentation

A 71-year-old woman was admitted to our Department of Neurology for tinnitus in the head. The cerebral magnetic resonance angiography (MRA) detected atherosclerotic cerebral arteries and bilateral stenosis of the middle cerebral arteries. The patient underwent DSA for further diagnostic work-up. The total amount of iopamidol used during the procedure was 110 ml. The patient experienced headache during the procedure, followed by dizziness with nausea and vomiting. Despite treatment with anti-oedema medications, her clinical status was gradually deteriorating and ended up with deep coma due to irreversible cerebral oedema which was confirmed by cerebral computed tomography (CT). Finally, the patient died 56 days after the procedure due to irreversible fatal cerebral oedema.

Conclusions

This report documents that iopamidol-induced encephalopathy may not always have a benign outcome and can result in irreversible fatal cerebral oedema.

Transient cortical blindness following intracardiac repair of congenital heart disease in an 11-year-old boy

Postoperative blindness (PB) primarily involves reception and conductance parts of the visual pathway due to ischemia following cessation of blood supply, for example, retinal vascular occlusion. Although a rare cause of PB, cortical blindness (CB), which results from ischemia/infarction of visual cortex, has a poor outcome due to its mostly nonreversible nature. Ischemic optic neuropathy is the most common cause of PB following cardiac surgeries. CB following cardiac surgeries involving cardiopulmonary bypass has been rarely reported. Only a few of those articles reported partial or complete reversal of CB. We report an incidence of transient CB in an 11-year-old child who was operated for double chambered right ventricle with ventricular septal defect.

[Prolonged reversible cortical blindness over 5 days after cardiac catheterization]

We present a case of a 49-year-old man with angina pectoris. He developed transient cortical blindness (TCB) with focal neurological symptoms following coronary angiography. Two cranial magnet resonance studies within 3 days showed no morphological changes. Clinically the patient developed complex focal epilepsy, which was symptomatically treated. Under intensive monitoring, including hypertension control, the patient improved after 5 days of blindness with restoration of his vision on day 6. The exact mechanism of TCB is still speculative, but could be caused in this case by a toxic effect of contrast dye that was administered. There is no definitive evidence to suggest that a certain treatment regime improves the natural history of the disease. However, control of risk factors and prevention of selective cerebral angiography may increase preventive strategies for this highly devastating complication.

Cortical blindness post coronary angiogram: A rare but frightening complication

Cortical blindness is a rare but frightening complication following coronary angiogram probably due to contrast penetration in occipital lobes in susceptible individuals [1, 2].

An atypical case of contrast-induced encephalopathy after carotid artery stenting

Neurotoxicity caused by contrast agents is a rare and less known complication of percutaneous carotid and coronary interventions. Radiological signs, such as cortical enhancement and brain edema, are of utmost importance in diagnosis. A 70-year-old female patient underwent left carotid artery stenting to treat a post-traumatic asymptomatic carotid dissection. Three hours after intervention, a mild aphasia developed with no brain alteration on diffusion-weighted magnetic resonance imaging (DW-MRI). Twelve hours after intervention, symptoms worsened but a new DW-MRI scan showed no pathological findings. Since a contrast-induced encephalopathy was diagnosed, fluid administration was raised to 2 mL/kg/h and the neurological status progressively improved. In the following three days, neurological deficit slowly regressed. Two weeks after intervention, aphasia had disappeared and a further cerebral DW-MRI scan detected no brain alteration. Typical radiological signs are described in association to contrast encephalopathy. Nevertheless, vascular interventional physicians should be well aware of this condition also when those signs are lacking.

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.

A case of contrast-induced encephalopathy using iodixanol

PURPOSE

To document a heretofore unreported complication of the contrast agent iodixanol during an endovascular procedure.

CASE REPORT

A 76-year-old woman with a history of coronary artery disease was admitted to the emergency department for recurrent transient ischemic attacks. Before combined percutaneous transluminal coronary angioplasty and carotid artery stenting (CAS) using iodixanol, the patient suffered from concomitant unstable angina and recurrent transient ischemic attacks. The total amount of iodixanol used during the CAS procedure was 300 mL. Contrast-induced encephalopathy, which manifested as aphasia, stupor, and full hemiparesis immediately after the combined procedure, was diagnosed by urgent computed tomography. Treatment was based on anti-edema drugs, and the patient made a complete recovery within 48 hours, without any neurological sequelae.

CONCLUSION

Although previously reported in relation to other types of contrast media, contrast-induced encephalopathy has never been described as a complication of an endovascular procedure using iodixanol.

Transient cortical blindness after thoracic endovascular aneurysm repair

We report a patient who presented with transient cortical blindness 12 hours after completion of a thoracic endovascular aneurysm repair. Computed tomography of the brain demonstrated no acute findings. The patient's symptoms resolved spontaneously after 72 hours. To our knowledge, this is the first report of transient cortical blindness after endovascular aortic aneurysm repair. This is an uncommon diagnosis that is important to recognize in a modern vascular surgery practice.

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.

Transient encephalopathy from angiographic contrast: a rare complication in neurointerventional procedures

Neurotoxicity from contrast media used in angiography is a rare complication from these procedures. The infrequency with which it is encountered makes it a diagnostic challenge. We present the case of a 51-year-old male who, 30 min after successful angiography for treatment of a right carotid-ophthalmic fusiform aneurysm with a stent, developed psychomotor agitation, disorientation, and progressive left faciobrachial hemiparesis (4/5). An emergency nonenhanced CT showed marked cortical enhancement and edema in the right cerebral hemisphere. Cortical enhancement is thought to be secondary to contrast extravasation due to disruption of the blood-brain barrier. Angiography was performed immediately, without any pathologic findings. After this procedure there was an increase in the left faciobrachial hemiparesis (3/5), right gaze deviation, Gerstmann syndrome, and left anosognosia and left homonymous hemianopsia. Endovenous dexamethasone and mannitol were initiated. Twenty-four hours later an MRI showed no signs of acute infarct, just gyriform signal increase in the right cerebral hemisphere on FLAIR and a decrease in the edema observed before. The patient had progressive improvement of his neurological deficit. A control MRI done 5 days later was normal. The patient recovered completely and was discharged. This rare entity should be kept in mind but diagnosed only when all other causes have been ruled out, because more important and frequent causes, such as acute infarct, must be excluded promptly.

Isolated bilateral blindness as the sole manifestation of transient ischaemic attacks

PURPOSE

To explain the rare phenomenon of acute transient bilateral blindness without additional ophthalmological or neurological symptoms and signs.

METHODS

Six patients with isolated bilateral visual loss lasting 1-15 mins and occurring simultaneously in both eyes were evaluated. Clinical observation, neuroimaging (CT, MRI, MR-angiography), extra- and transcranial Doppler and vascular risk factors assessment were performed.

RESULTS

Cortical blindness due to bilateral occipital lobe transient ischaemic attacks (TIAs) was established as the most likely cause of acute transient visual loss in all patients.

CONCLUSION

We suggest that in cases of transient bilateral blindness with sudden onset, appearing simultaneously in both visual fields, a bilateral ischaemia of the visual cortex should be suspected even if other neurological symptoms are lacking. Patients should be managed in the same way as patients with vertebrobasilar TIAs.

Cortical blindness during coil embolization of an unruptured intracranial aneurysm--case report

A 62-year-old woman suffered transient cortical blindness during coil embolization for a saccular aneurysm in the posterior circulation, with cerebral angiography using non-ionic contrast material. Just before completion of the procedure, the patient showed abrupt onset of restlessness and blindness. At this point 150 ml of contrast material had been injected into the left vertebral artery. Immediate computed tomography showed persistence of contrast medium in the bilateral occipital lobes and part of the left frontal lobe. Repeat angiography showed no evidence of embolism. Single photon emission computed tomography obtained the next day showed decreased perfusion in the bilateral occipital lobes. Magnetic resonance imaging on the third day showed multiple lesions in the bilateral occipital lobes. Her vision was restored gradually. Transient cortical blindness may be associated with osmotic disruption of the blood-brain barrier in the bilateral occipital lobes. Endovascular neurosurgeons must be aware of this rare complication.

Simultaneous ischemic and neurotoxic brain damage after coronary angiography

Transient cortical blindness following intra-arterial catheter angiography is a known rare complication. We report the case of a 56-year-old man who suffered from transient cortical blindness and neuropsychological deficits after coronary angiography. Serial CT scans revealed reversible pathologic parenchymal contrast enhancement of the right occipital lobe as well as left middle cerebral artery infarction at the same time. CT changes and time course of clinical symptoms are presented and discussed for both lesions of presumably different etiology.

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

The magnetic resonance imaging findings in a case of transient cortical blindness (TCB) after cardiac catheterization are described for the first time. In addition, a literature review of TCB, comparison with reversible posterior leukoencephalopathy, and a hypothesis regarding the pathophysiology of TCB are presented.

Cortical blindness after subclavian arteriography

Transient cortical blindness is a rare complication of angiographic contrast use. A 64-year-old man experienced transient cortical blindness after subclavian arteriography for an occluded axillofemoral graft. The literature on transient cortical blindness is reviewed.