Transient Monocular Blindness Research Articles

Transient Monocular Blindness Presenting as Central Retinal Vein Occlusion Secondary to MOGAD Optic Neuritis (P9-14.008)

Transient Monocular Blindness Presenting as Central Retinal Vein Occlusion Secondary to MOGAD Optic Neuritis (P9-14.008)

Transient Monocular Visual Loss (Amaurosis Fugax): How Does Age Impact Diagnosis?

Transient monocular visual loss (TMVL), also known as transient monocular blindness or amaurosis fugax ("fleeting blindness"), is a temporary loss of vision often due to ischemia to the retina. While acute TMVL should be considered an emergency that further requires exhaustive investigation, there are some cases in which TMVL arises secondary to benign causes. Age has a major impact in the diagnosis of ischemia and although the differential diagnosis of TMVL can be broad, timely and appropriate history, examination, diagnostic testing, and treatment can be vision- or life-saving. We review the causes of TMVL and the impact of age on the differential diagnoses and management.

Surgical Ligation of an Indirect Carotid-Cavernous Fistula With Exclusive Retrograde Cortical Venous Drainage: 2-Dimensional Operative Video.

Indirect carotid-cavernous fistulas (CCFs) are abnormal connections between the cavernous sinus and branches of the internal and external carotid arteries. Indirect CCFs with progressive cortical venous drainage require obliteration to prevent neurological decline secondary to their rupture or progression. While indirect CCFs are often treated with transvenous embolization of their venous outflow through the inferior or superior petrosal sinuses, facial vein, or superior ophthalmic vein, CCFs failing previous embolization may be best treated with surgical ligation. Here we present the case of a 30-year old woman who, 3 years before presentation to our institution, presented with transient monocular blindness to an outside institution. Catheter angiography revealed a CCF without cortical venous drainage which was partially embolized with coils. Catheter angiography at the 1-year follow-up revealed CCF progression characterized by cortical venous drainage into a right cortical vein, basal temporal vein, and the vein of Labbé. The lesion was treated with partial onyx embolization. Two years later, further evaluation at our institution demonstrated cortical venous ectasia-confirming CCF progression. Though asymptomatic, the risk of neurological decline secondary to progression or rupture of the lesion was high given the progressive cortical venous drainage, and treatment was indicated. As the lesion failed endovascular therapy twice, the patient underwent a right pterional craniotomy for surgical disconnection of the CCF's main draining vein and other fistulous connections. The patient had an uneventful recovery, and postoperative catheter angiography suggested complete obliteration of the lesion. Appropriate consent was obtained for the publication of the cadaver's image. The patient consented to the procedure and video recording.

Systemic lupus erythematosus mimicking retinal migraine: a case report

Background Retinal migraine is a diagnosis of exclusion and is characterized by repeated episodes of transient monocular blindness associated with migraine. We report a case of systemic lupus erythematosus with acute episodes mimicking retinal migraines. Case report A 46-year-old woman with a history of migraine with aura since her 20s and Evans syndrome presented with episodic transient monocular blindness. Retinal migraine was considered as the cause, and migraine prophylaxis initially reduced its frequency. After 5 months, the frequency increased, with chilblain-like lupus lesions on her extremities. Laboratory testing revealed lymphopenia and hypocomplementemia, fulfilling the diagnostic criteria for systemic lupus erythematosus, which may have caused Evans syndrome and transient monocular blindness, mimicking retinal migraines. After intravenous methylprednisolone and rituximab therapy, the transient monocular blindness episodes did not recur. Conclusion Given the clinical presentation, systemic lupus erythematosus should be considered as a cause of transient monocular blindness and should be distinguished from retinal migraine.

Ophthalmic Artery ‘Steal’ Phenomenon as a Possible Mechanism of Transient Monocular Blindness in Internal Carotid Artery Dissection

Ophthalmic Artery ‘Steal’ Phenomenon as a Possible Mechanism of Transient Monocular Blindness in Internal Carotid Artery Dissection

Usefulness of orbital colour Doppler ultrasound in vascular-related monocular vision loss.

Acute, painless, monocular vision loss (APMVL) usually has a vascular aetiology. We conducted a prospective observational study from 2011 to 2018 to analyse the added value of colour Doppler imaging to assess orbital vessel blood flow in the diagnosis of APMVL. The study included 67 patients (39 [58.2%] men; mean age, 65.9 years [SD 13.7]) with APMVL evaluated at the Neurosonology Laboratory within the first 5 days of symptom onset, who were classified as having either transient or persistent monocular blindness. The blood flow in the ophthalmic and central retinal arteries was assessed using colour Doppler ultrasound with a linear 7.5-MHz transducer. Thirty-three (49.3%) patients presented transient monocular blindness, with reduced blood flow in either the ophthalmic or central retinal artery. The group with persistent vision loss included 24 cases of central retinal artery occlusion (CRAO) and 10 cases of ischaemic optic neuropathy (35.8% and 14.9%, respectively, of the total sample). These patients were older and had a higher prevalence of hypertension and mild carotid atherosclerosis. Orbital colour Doppler ultrasound (OCDUS) clarified the mechanism/cause of the ischaemia in 11 (16.4%) patients and showed abnormal flow in 46 (68.7%) patients, confirming the vascular origin in 19 (57.6%) of the transient monocular blindness cases. Lower peak systolic velocity was observed in patients with CRAO (p < 0.001), and a velocity < 10 cm/s in the central retinal artery was independently associated with the diagnosis of CRAO. OCDUS can be helpful in confirming the vascular cause and identifying the aetiology of APMVL.

Vascular emergencies in neuro-ophthalmology.

The cerebral vascularization is assured by the 2 internal carotids and 2 vertebral arteries, and the Willis circle. Carotid artery obstruction is the most common abnormality associated with ocular ischemic syndrome. Obstruction may be due to atheromatous plaque, external compression, arteritis, or dissection of the artery. An atheromatous lesion of the carotid artery is the most frequent lesion responsible for ocular ischemic syndrome. The signs and symptoms of ocular ischemic syndrome are associated with severe hypoperfusion of the eye. Inflammatory lesions of the carotid artery are responsible for decreased flow in the carotid system. Other vascular emergencies are carotid artery dissection, Horton arteritis, aneurysms and carotid-cavernous fistula. The most common ocular signs and symptoms are transient monocular blindness, persistent monocular blindness, ocular ischemia, Claude Bernard Horner syndrome and oculomotor palsies.The carotid pathology can be a life-threatening pathology and it is important to recognize all these signs and symptoms. A multi-specialty approach will prevent misdiagnosis and lead to a better patient management.Abbreviations: OIS = ocular ischemic syndrome, TMB = transient monocular blindness, TIA = transient ischemic attack, ESR = erythrocyte sedimentation rate, CRP = C reactive protein, NVE = neovascularization elsewhere in the retina, NVD = neovascularization on the disc, AION A = anterior ischemic arteritic optic neuropathy, CBH = Claude Bernard Horner syndrome, MRI = magnetic resonance imaging

Annals for Educators - 19 November 2019.

Annals for Educators - 19 November 2019.

Atrial Fibrillation: An Underestimated Cause of Ischemic Monocular Visual Loss?

Introduction: Atrial fibrillation (AF) is a major cause of ischemic stroke and Transient Ischemic Attack (TIA) and investigation for paroxysmal AF is recommended following an embolic brain event. In contrast, retinal ischemic monocular blindness is traditionally considered most linked to carotid artery disease (CAS) and investigating for AF is less vigilant. We aimed to determine the prevalence of AF in patients with ischemic monocular blindness. Methods: Consecutive records of all patients presenting to a daily TIA clinic with transient or permanent ischemic monocular blindness were reviewed, January 2014-October 2016. Results: Of 400 patients, 224 (56.0%) were male, mean age 64.5 years (SD 15.1). A total of 263 (66%) presented with transient and 137 (34%) with permanent ischemic monocular blindness. ECG was performed in 364 patients (91%) but only 211 (52%) had further cardiac monitoring. The vast majority (97.3%) had carotid imaging. Thirty-six patients (9%) were found to have AF while 53 (14%) had ipsilateral CAS. Median ABCD2 score was 1 in AF and non-AF groups. Only 55% of known AF patients were anticoagulated at presentation, despite all having CHADVASC2 score greater than or equal to 1. Patients with AF had more hypertension (P = .004), previous TIA (P = .002), previous stroke (P = .044) and ischemic heart disease (P = .022) with no difference in age (P = .791), diabetes (P = .563), smoking (P = .460) nor hypercholesterolaemia (P = .083). Conclusions: A total of 9% of patients with ischemic monocular blindness had AF. This is an underestimate, as only 53% of patients had prolonged cardiac monitoring. Known AF was suboptimally managed with only 55% receiving anticoagulation despite being eligible.

Duplex ultrasound for the diagnosis of symptomatic carotid stenosis: real value in clinical practice

Background: Atherosclerotic plaque leading to internal carotid stenosis greater than 50%, accounts for about 10 to 15% of all acute ischemic stroke (AIS) causes. Stenosis identification and severity is frequently estimated by Duplex ultrasound (DUS) assessment. Symptomatic carotid disease is defined as focal neurologic symptoms with sudden onset and related to the appropriate carotid artery cerebral distribution. It includes established acute ischemic stroke, one or more transient ischemic attacks characterized by focal neurologic dysfunction or transient monocular blindness, in the preceding 6 months of the carotid stenosis identification. Revascularization should be considered in symptomatic patients with a carotid artery stenosis of 50–69% and recommended in symptomatic patients with a stenosis of 70–99%. In our clinical practice it is seen frequently the indiscriminate use of DUS in the etiological study for AIS. Therefore, we consider the possibility of such an exam being excessively performed, since most patients may have no indication for DUS assessment. Objectives: (1) estimation of symptomatic carotid artery disease prevalence in hospitalized patients with the diagnosis of AIS and ≥ 50% carotid stenosis; (2) determination of carotid artery revascularization in this subgroup of patients; (3) evaluation of the centre clinical practice and to determine a real estimative of the therapeutic impact associated with DUS in patients with AIS. Methods: Retrospective observational cohort study of patients admitted with established AIS within the year of 2017 and followed for an additional 12 month period. Inclusion criteria: a definite diagnosis of AIS (based in symptoms within 24 hours’ period and/or image in CT scan suggestive of AIS), date of hospitalization within the mentioned timeframe and patients who underwent carotid DUS within the first 6 months after the event. No hemorrhagic stroke or transient ischemic attacks were considered in this study. Results: Of the 198 stroke patients, 144 (72%) underwent Doppler ultrasound. The average age was 78 years, 50% were male and 23.6% had previous stroke. From the total 144 included patients, only 18 (12.5%) had stenosis ≥50%, and 9 (6.25%) had ipsilateral lesions to the carotid stenosis. The remaining had lesions contralateral to the stenosis or lacunar strokes. Considering this, 6.25% of patients were assumed to have symptomatic carotid disease. None underwent surgical intervention for various reasons (e.g. high risk procedure, contraindications, high degree disability and/or multiple comorbidities). Conclusions: The present study reinforces the idea that etiological study of AIS is essential, and DUS appears as a first line exam. However, we emphasize that DUS should only be performed in patients with non-disabling AIS (mRS score 0–2) who are candidates for vascular intervention.

TRANSIENT RETINAL ISCHEMIC ATTACKS IN THE PRACTICE OF A NEUROLOGIST

Transient ischemic attacks (TIA) are acute attacks of focal or cerebral neurological disorders caused by a violation of cerebral circulation, lasting from several seconds to 24 hours. With transient ischemia in the basin of the internal carotid artery, characteristic visual impairments develop on the side of the lesion due to relative circulatory insufficiency of the retina, short-term transient lightning-fast monocular blindness, amaurosis fugas combined with hemiparesis on the opposite side (optico-pyramidal syndrome). Transient retinal ischemic attacks are a fairly common disease, but many issues of its clinical manifestation and diagnosis remain unknown, which affects the quality of treatment. Such patients need urgent examination and treatment, with simultaneous differential diagnosis of TIA with other transient neurological.

Comparison of Clinical Characteristics among Subtypes of Visual Symptoms in Patients with Transient Ischemic Attack: Analysis of the PROspective Multicenter registry to Identify Subsequent cardiovascular Events after TIA (PROMISE-TIA) Registry

A transient visual symptom (TVS) is a clinical manifestation of transient ischemic attack (TIA). The aim of this study was to investigate differences in clinical characteristics among subtypes of TVS using multicenter TIA registry data. Patients with TIA visiting within 7 days of onset were prospectively enrolled from 57 hospitals between June 2011 and December 2013. Clinical characteristics were compared between patients with 3 major subtypes of TVS (transient monocular blindness [TMB], homonymous lateral hemianopia [HLH], and diplopia). Of 1365 patients, 106 (7.8%) had TVS, including 40 TMB (38%), 34 HLH (32%), 17 diplopia (16%), and 15 others/unknown (14%). Ninety-one patients with 1 of the 3 major subtypes of TVS were included. Symptoms persisted on arrival in 12 (13%) patients. Isolated TVS was significantly more common in TMB than in HLH and diplopia (88%, 62%, and 0%, respectively; P < .001). Duration of symptoms was shorter in patients with TMB than those with HLH (P = .004). The ABCD2 score was significantly lower in patients with TMB compared with those with HLH and diplopia (median 2 [interquartile range 2-3] versus 3 [2-4] and 4 [2-5], respectively; P = .005). Symptomatic extracranial internal carotid artery stenosis or occlusion was seen in 14 (16%) patients, and was more frequent in TMB than in HLH and diplopia (28%, 9%, and 0%, respectively; P = .015). TVS was an uncommon symptom in our TIA multicenter cohort. Some differences in clinical characteristics were found among subtypes of TVS.

Charles Miller Fisher: the 65th anniversary of the publication of his groundbreaking study "Transient Monocular Blindness Associated with Hemiplegia".

Charles Miller Fisher is considered the father of modern vascular neurology and one of the giants of neurology in the 20th century. This historical review emphasizes Prof. Fisher's magnificent contribution to vascular neurology and celebrates the 65th anniversary of the publication of his groundbreaking study, "Transient Monocular Blindness Associated with Hemiplegia."

Ultrasound Technique to Detect Internal Jugular Valve Incompetence and Clinical Implications

The internal jugular ( IJ) valves are absent in 6% to 13%, more commonly in the left-sided than the right-sided veins, and typically bicuspid valves ( 66%), but can be unicuspid (15%), tricuspid (6%), or absent (13%). They are located at an approximately 0.3-0.5 cm above the junction with the brachiocephalic vein, but the position in the neck or chest can vary from being almost directly posterior, to 3 cm inferior and lateral, to the head of the clavicle. The closure of the IJ valve occurs during diastole when the atrium transmits backward pressure from the right atrium into the superior vena cava, then into the IJ vein. The competency of the IJ valves has been previously tested by IJ venography during Valsalva maneuver or cough, a Doppler sample of the IJ vein flow combined with M-mode ultrasonography of the IJ valve during Valsalva, the color flow imaging (CFI) of the IJ vein. However, IJ venography is invasive, while it is difficult to interpret duplex and CFI data of the IJ vein due to slow and swirling flow in IJ vein. We have introduced the use of air contrast ultrasonography with B-mode imaging during Valsalva, so called the air contrast ultrasound venography (ACUV). The ACUV provides rapid, reliable, practical, and noninvasive, method for detection of absent or incompetent IJ valves. In addition the ACUV is more sensitive to assess IJ valve incompetence due to well visualized of the air contrast bubbles from the IJ venous reflux. The IJ veins are the principle route of venous drainage of the brain through cerebral vein emptying into the dural venous sinuses, then into the IJ veins. The IJ valve is the only valve between the heart and the brain, preventing venous reflux into the IJ vein. Uni-or bilateral IJ valve incompetence prevalence ranges from 29% in the young adult population to 33-45% in healthy elderly subjects. However, the IJ valve incompetence with IJ vein reflux has been found more frequently in several neurological diseases such as transient global amnesia, transient monocular blindness, cough headache, primary exertional headache and in some medical conditions such as elevated central venous pressure, congestive heart disease, tricuspid valve regurgitation, primary pulmonary hypertension, chronic obstructive pulmonary disease, prolong positive end-expiratory pressure ventilators and status post IJ vein cannulation, probably resulting from cerebral venous outflow impairment. Thus, the incompetent IJ valves leading to cerebral venous hypertension might play a major role in the mechanism of these neurological disorders.

Acute Visual Loss

Acute visual loss is a frightening experience, a common ophthalmic emergency, and a diagnostic challenge. In this review, the author focusses on the diagnosis of transient monocular blindness and visual loss due to infarction of the retina and/or the optic nerve-the ocular parallel of cerebral stroke.

Transient monocular blindness and the risk of vascular complications according to subtype: a prospective cohort study.

Patients with transient monocular blindness (TMB) can present with many different symptoms, and diagnosis is usually based on the history alone. In this study, we assessed the risk of vascular complications according to different characteristics of TMB. We prospectively studied 341 consecutive patients with TMB. All patients were interviewed by a single investigator with a standardized questionnaire; reported symptoms were classified into predefined categories. We performed Cox regression analyses with adjustment for baseline vascular risk factors. During a mean follow-up of 4.0 years, the primary outcome event of vascular death, stroke, myocardial infarction, or retinal infarction occurred in 60 patients (annual incidence 4.4 %, 95 % confidence interval (CI) 3.4–5.7). An ipsilateral ischemic stroke occurred in 14 patients; an ipsilateral retinal infarct in six. Characteristics of TMB independently associated with subsequent vascular events were: involvement of only the peripheral part of the visual field (hazard ratio (HR) 6.5, 95 % CI 3.0–14.1), constricting onset of loss of vision (HR 3.5, 95 % CI 1.0–12.1), downward onset of loss of vision (HR 1.9, 95 % CI 1.0–3.5), upward resolution of loss of vision (HR 2.0, 95 % CI 1.0–4.0), and the occurrence of more than three attacks (HR 1.7, 95 % CI 1.0–2.9). We could not identify characteristics of TMB that predicted a low risk of vascular complications. In conclusion, careful recording the features of the attack in patients with TMB can provide important information about the risk of future vascular events.Electronic supplementary materialThe online version of this article (doi:10.1007/s00415-016-8189-x) contains supplementary material, which is available to authorized users.

Diagnosis of Transverse Sinus Hypoplasia in Magnetic Resonance Venography: New Insights Based on Magnetic Resonance Imaging in Combined Dataset of Venous Outflow Impairment Case-Control Studies: Post Hoc Case-Control Study.

In previous studies of transverse sinus (TS) hypoplasia, discrepancies between TS diameter measured by magnetic resonance venography (MRV) and contrast T1-weighted magnetic resonance (contrast T1) were observed. To investigate these discrepancies, and considering that TS hypoplasia is associated with neurological disorders, we performed a post hoc analysis of prospectively collected data from 3 case–control studies on transient global amnesia (TGA), transient monocular blindness (TMB), and panic disorders while retaining the original inclusion and exclusion criteria. Magnetic resonance (MR) imaging of 131 subjects was reviewed to evaluate TS diameter and the location and degree of venous flow stenosis and obstruction.MRV without contrast revealed that TS hypoplasia was observed in 69 subjects, whom we classified into 2 subgroups according to the concordance with contrast T1 observations: concordance indicated anatomically small TS (30 subjects), and discrepancy indicated that the MRV diagnosis is in fact flow-related and that TS is not anatomically small (39 subjects). The latter subgroup was associated with at least 1 site of venous compression/stenosis in the internal jugular vein (IJV) or the left brachiocephalic vein (BCV) (P < 0.001), which was significantly larger in patients than controls. Compensatory dilatation of contralateral TS diameter was only observed with MRV, not with contrast T1 imaging.The clinical implication of these results is that using MRV only, IJV/BCV compression/stenosis may be misdiagnosed as TS hypoplasia. And contralateral TS have no compensatory dilatation in its diameter in contrast T1 imaging, just compensatory increased flow volume.

Recurrent Transient Monocular Blindness Caused by Retinal Vasospasm

Received March 25, 2015 Revised June 10, 2015 Accepted June 10, 2015 Address for correspondence: Jae-won Jang, MD Department of Neurology, Kangwon National University School of Medicine, Kangwon National University Hospital, 156, Baengnyeong-ro, Chuncheon, 24289 Korea Tel: +82-33-258-9174 Fax: +82-33-258-2103 E-mail: light26@hanmail.net 일과성 단안실명(transient monocular blindness)은 대개 시신 경(optic nerve) 혹은 망막혈류순환(retinal circulation)의 관류저 하(hypoperfusion)로 발생한다. 색전질환 혹은 경동맥의 동맥경 화가 대부분의 원인이며, 보통 항응고제나 항혈소판제로 치료한 다. 내경동맥의 심각한 협착을 갖고 있는 환자는 동맥내막절제 술(endarterectomy)을 고려하게 된다. 색전혈전과 경동맥질환이 배제됐다면, 일과성단안실명의 원 인으로 망막혈관연축(retinal vasospasm)을 반드시 감별해야 하 며, 이는 의료진이 의심하지 않으면 감별하기 어려운 병인이다.

対側浅側頭動脈からの側副血行を有する総頸動脈閉塞に対するバイパス術前後の血行動態の評価に浅側頭動脈超音波検査が有用であった一例

A 77-year-old man with a history of radiation therapy for pharyngeal cancer and consequent asymptomatic left common carotid artery (CCA) occlusion showed asymptomatic ischemic stroke and left transient monocular blindness, and he was admitted to our hospital. He was found to have an indication for bypass surgery because of a remarkable reduction in cerebral blood flow in the ipsilateral middle cerebral artery (MCA) territory. Carotid ultrasonography revealed retrograde blood flow of the ipsilateral external carotid artery (ECA) and a U-turn phenomenon to the internal carotid artery (ICA). Cerebral angiography demonstrated spontaneous bonnet bypass flow from the right superficial temporal artery (STA) to the left STA, but the blood flow via the bypass was not enough to supply the left MCA. Bypass surgery to anastomose the bonnet bypass to the left MCA was performed, and postsurgical cerebral blood flow to the ipsilateral MCA territory improved. On STA duplex ultrasonography (STDU), the pulsatility index value of the contralateral STA changed from an ECA pattern before surgery to an ICA pattern after. Moreover, postsurgical mean flow velocity of the bonnet bypass to the left MCA was relatively higher than the presurgical retrograde mean flow velocity of the left STA. These ultrasonographic findings correlated with those on single photon emission computed tomography (SPECT) and cerebral angiography. As demonstrated in the present case, ultrasonography including STDU is useful in the evaluation of cerebral hemodynamics before and after cerebral artery bypass surgery and in the usual STA-MCA anastomosis.

Brain venous haemodynamics, neurological diseases and mathematical modelling. A review

Behind Medicine (M) is Physiology (P), behind Physiology is Physics (P) and behind Physics is always Mathematics (M), for which I expect that the symmetry of the quadruplet MPPM will be compatible with the characteristic bias of hyperbolic partial differential equations, a theme of this paper. I start with a description of several idiopathic brain pathologies that appear to have a strong vascular dimension, of which the most prominent example considered here is multiple sclerosis, the most common neurodegenerative, disabling disease in young adults. Other pathologies surveyed here include retinal abnormalities, Transient Global Amnesia, Transient Monocular Blindness, Ménière’s disease and Idiopathic Parkinson’s disease. It is the hypothesised vascular aspect of these conditions that links medicine to mathematics, through fluid mechanics in very complex networks of moving boundary blood vessels. The second part of this paper is about mathematical modelling of the human cardiovascular system, with particular reference to the venous system and the brain. A review of a recently proposed multi-scale mathematical model then follows, consisting of a one-dimensional hyperbolic description of blood flow in major arteries and veins, coupled to a lumped parameter description of the remaining main components of the human circulation. Derivation and analysis of the hyperbolic equations is carried out for blood vessels admitting variable material properties and with emphasis on the venous system, a much neglected aspect of cardiovascular mathematics. Veins, unlike their arterial counterparts, are highly deformable, even collapsible under mild physiological conditions. We address mathematical and numerical challenges. Regarding the numerical analysis of the hyperbolic PDEs, we deploy a modern non-linear finite volume method of arbitrarily high order of accuracy in both space and time, the ADER methodology. In vivo validation examples and brain haemodynamics computations are shown. We also point out two, preliminary but important new findings through the use of mathematical models, namely that extracranial venous strictures produce chronic intracranial venous hypertension and that augmented pressure increases the blood vessel wall permeability.