Generalized anosognosia, anosodiaphoria, and visual hallucinations with bilateral enucleation after severe bifrontal brain injury: a case report describing similarities with and differences from Anton syndrome.

Visual anosognosia, associated with confabulations and cortical blindness in the context of occipital lobe injury, is known as Anton syndrome. Patients with this syndrome strongly deny their vision loss and confabulate to compensate for both visual loss and memory impairments. In this article, we present a case of a patient with some similarities to Anton syndrome, however, with several differences in clinical presentation. Bifrontal brain injury, bilateral enucleation, affective indifference (anosodiaphoria), generalized anosognosia, and the conviction that vision will resume mark clear clinical differences with Anton syndrome. Differentiating these findings from Anton syndrome will help occupational therapists, neuropsychologists, speech-language pathologists, physical therapists, and physicians when assessing frontal lobe brain injury with total and partial visual loss. This case demonstrates that visual anosognosia and confabulations can occur without occipital lobe dysfunction or cortical blindness.

Cortical blindness after percutaneous vertebroplasty: a case report and comprehensive review of the literature.

OBJECTIVE: Many complications but cortical blindness after percutaneous vertebroplasty has been rarely reported. Here, we describe a case who developed cortical blindness after percutaneous vertebroplasty. We also reviewed the literature to find the possible causes of this complication and its treatment. METHODS: Case report and literature review. RESULTS: A 71-year-old woman experienced cortical blindness after percutaneous vertebroplast. She developed dizziness, nausea, sweating, blood pressure changes, and vision loss during the procedure. MRI confirmed bilateral cerebral infarctions. The patient recovered with conservative treatment. CONCLUSIONS: Percutaneous vertebroplasty, though helpful, carries a rare risk of cortical blindness. Surgeon awareness is crucial for informing patients of this potential complication.

Pheochromocytoma manifesting as cortical blindness secondary to PRES with associated TMA: a case report and literature review.

BACKGROUND: Pheochromocytomas are neoplasms originating from neuroectodermal chromaffin cells leading to excess catecholamine production. They are notorious for causing a triad of headaches, palpitations, and sweats. Though the Menard triad is one to be vigilant of, symptomatic presentation can vary immensely, hence the tumor earning the label "the great masquerader." CASE PRESENTATION: We report a case of pheochromocytoma initially presenting with cortical blindness secondary to posterior reversible encephalopathy syndrome and thrombotic microangiopathy from malignant hypertension. Our patient was seen in our facility less than a week prior to this manifestation and discharged after an unremarkable coronary ischemia work-up. In the outpatient setting, she had been prescribed multiple anti-hypertensives with remarkably elevated blood pressure throughout her hospitalization history. CONCLUSION: Pheochromocytoma presenting with malignant hypertension and hypertensive encephalopathy should be expected if left untreated; nonetheless, the precipitation of cortical blindness is rare in the literature. This case contributes an additional vignette to the growing literature revolving adrenal tumors and their symptomatic presentation along with complex management. It also serves to promote increased diagnostic suspicion among clinicians upon evaluating patients with refractory hypertension.

Delayed-onset hypoxic cortical blindness: coming back from the abyss.

PURPOSE: To report a case of typical delayed-onset hypoxic cortical blindness that occurred few days after resuscitation from drowning in a young male. METHODS: Neurological and ophthalmological examination were performed including optical coherence tomography (OCT), Goldmann perimetry, pattern electroretinogram (pERG), pattern and flash visual evoked potentials (pVEP and fVEP) and brain magnetic resonance imaging (MRI). RESULTS: At presentation, at day 12 post-hypoxic incident, best corrected visual acuity (BCVA) was reduced to hand motion OU with an abolished optokinetic nystagmus, a normal fundus and no relative afferent pupillary defect. Macular and peripapillary OCT were normal. Goldmann perimetry revealed bilateral centrocecal scotoma. pERG was normal while pVEPs were undetectable and fVEPs were abnormal with delayed, decreased and disorganized responses, without interhemispheric asymmetry. Brain MRI disclosed a bilateral cortical-subcortical occipital hypersignal with laminar necrosis and thus confirmed the diagnosis of delayed-onset hypoxic cortical blindness. Visual rehabilitation, including visual stimulation in the scotomatous areas, was associated with a dramatic and rapid visual improvement with a BCVA of 20/32 OU, an ability to read after 2 weeks (day 30 post-hypoxic incident), and a reduction in the size of the scotoma. CONCLUSION: Delayed-onset hypoxic cortical blindness is a rare presentation of cortical blindness that develops few days after a cerebral hypoxic stress. While initial presentation can be catastrophic, visual improvement may be spectacular and enhanced with visual rehabilitation.

Optic Tract Shrinkage Limits Visual Restoration After Occipital Stroke.

Background and Purpose: Damage to the adult primary visual cortex (V1) causes vision loss in the contralateral visual hemifield, initiating a process of trans-synaptic retrograde degeneration. The present study examined functional implications of this process, asking if degeneration impacted the amount of visual recovery attainable from visual restoration training in chronic patients, and if restoration training impacted optic tract (OT) shrinkage. Methods: Magnetic resonance imaging was used to measure OT volumes bilaterally in 36 patients with unilateral occipital stroke. From OT volumes, we computed laterality indices (LI), estimating the stroke-induced OT shrinkage in each case. A subset of these chronic patients (n=14, 13±6 months poststroke) underwent an average of nearly 1 year of daily visual restoration training, which repeatedly stimulated vision in their blind field. The amount of visual field recovery was quantified using Humphrey perimetry, and post training magnetic resonance imaging was used to assess the impact of training on OT shrinkage. Results: OT LI was correlated with time since stroke: it was close to 0 (no measurable OT shrinkage) in subacute participants (<6 months poststroke) while chronic participants (>6 months poststroke) exhibited LI >0, but with significant variability. Visual training did not systematically alter LI, but chronic patients with baseline LI≈0 (no OT shrinkage) exhibited greater visual field recovery than those with LI>0. Conclusions: Unilateral OT shrinkage becomes detectable with magnetic resonance imaging by ≈7 months poststroke, albeit with significant interindividual variability. Although visual restoration training did not alter the amount of degeneration already sustained, OT shrinkage appeared to serve as a biomarker of the potential for training-induced visual recovery in chronic cortically blind patients.

Functional preservation and enhanced capacity for visual restoration in subacute occipital stroke.

Stroke damage to the primary visual cortex (V1) causes a loss of vision known as hemianopia or cortically-induced blindness. While perimetric visual field improvements can occur spontaneously in the first few months post-stroke, by 6 months post-stroke, the deficit is considered chronic and permanent. Despite evidence from sensorimotor stroke showing that early injury responses heighten neuroplastic potential, to date, visual rehabilitation research has focused on patients with chronic cortically-induced blindness. Consequently, little is known about the functional properties of the post-stroke visual system in the subacute period, nor do we know if these properties can be harnessed to enhance visual recovery. Here, for the first time, we show that 'conscious' visual discrimination abilities are often preserved inside subacute, perimetrically-defined blind fields, but they disappear by ∼6 months post-stroke. Complementing this discovery, we now show that training initiated subacutely can recover global motion discrimination and integration, as well as luminance detection perimetry, just as it does in chronic cortically-induced blindness. However, subacute recovery was attained six times faster; it also generalized to deeper, untrained regions of the blind field, and to other (untrained) aspects of motion perception, preventing their degradation upon reaching the chronic period. In contrast, untrained subacutes exhibited spontaneous improvements in luminance detection perimetry, but spontaneous recovery of motion discriminations was never observed. Thus, in cortically-induced blindness, the early post-stroke period appears characterized by gradual-rather than sudden-loss of visual processing. Subacute training stops this degradation, and is far more efficient at eliciting recovery than identical training in the chronic period. Finally, spontaneous visual improvements in subacutes were restricted to luminance detection; discrimination abilities only recovered following deliberate training. Our findings suggest that after V1 damage, rather than waiting for vision to stabilize, early training interventions may be key to maximize the system's potential for recovery.

Reversible Cortical Blindness in Pediatric Native Valve Endocarditis.

ABSTRACT: Native valve endocarditis, a rare phenomenon in children, can present with septic embolization and devastating consequences. We present a healthy child with bilateral cortical blindness due to native mitral valve endocarditis. After prompt medical and surgical therapy, he regained complete vision. Early surgical intervention resulted in the best outcome.

Transient cortical blindness in fat embolism syndrome---a diagnostic enigma.

Fat embolism syndrome (FES) is a serious life-threatening manifestation of the fat embolism phenomenon characterized by Bergman's triad of dyspnea, petechiae and mental confusion. While fat embolization into systemic circulation is common, FES occurs in a meagre 0.05%-3% of patients having isolated long bone fractures. Though visual symptoms are commonly attributed to fat embolism retinopathy and is a later occurrence, it may not always be the case. Cortical blindness has been seldom reported in association with FES, and less so as a presenting complaint. Furthermore, no previous literature has described the same in context of an isolated tibia fracture. We report a 20-year-old gentleman with an isolated right tibia shaft fracture who developed sudden onset diminution of vision in both eyes less than 24 h following trauma with no other complaints. Lack of any remarkable ophthalmoscopic findings or other symptoms left us with a diagnostic conundrum. He later went on to develop altered mentation, hypoxia and generalized tonic-clonic seizures with subsequent MRI revealing multiple cerebral fat emboli also involving both occipital lobes. Supportive measures were instituted and his general condition as well as vision gradually improved following which he underwent plate fixation of the fracture under spinal anaesthesia. The perioperative period was uneventful and he was discharged following staple removal. At one month of follow-up, the patient had no residual visual field defects or neurological deficits. Though FES is rare among isolated tibia fractures, this clinical catastrophe may strike in any unsuspected setting thereby warranting a high index of suspicion to ensure early diagnosis and improved patient outcomes.

A woman in her seventies with acute onset of blindness. / En kvinne i 70-årene med akutt blindhet.

BACKGROUND: Dural arteriovenous fistulae are among the most common causes of pulsatile tinnitus. Selective angiography can be necessary for a definitive diagnosis, but in rare cases has been reported to cause sudden cortical blindness. CASE PRESENTATION: We present a woman in her seventies for whom cerebral angiography revealed a dural arteriovenous fistula. Two hours after the angiography she experienced sudden bilateral blindness. A local cause of sudden visual loss was excluded by clinical examination, cerebral bleeding was excluded by CT scan, vascular spasms and occlusions were excluded by CT angiography and acute infarction over the bilateral parieto-occipital cortex was excluded by MRI. The CT scan did, however, show contrast enhancement in the visual cortex from the contrast given during the previously performed cerebral angiography. The patient's vision spontaneously recovered within six days after the angiography, with no residual neurological deficits in her subsequent clinical follow up. Surgery was later performed on her dural arteriovenous fistula, which successfully treated the pulsatile tinnitus. INTERPRETATION: Transient cortical blindness is a rare but dramatic complication after cerebral angiography, thought to be caused by the transient neurotoxic effects of iodine-containing contrast agents. When other causes of sudden blindness are excluded, the patient can be reassured about the excellent prognosis for this condition.

Surgical Treatment of a Child With Acute Cortical Blindness Caused by Depressed Skull Fracture.

Linear skull fractures are relatively common in children, however, it is rarer to see depressed fractures. This report details the case of a 7-year-old boy who was admitted to the emergency department with complete blindness after having experienced an in-car traffic accident. Brain tomography of the patient showed that a large, island-shaped piece of occipital bone was depressed on the visual cortex and superior sagittal sinus in the midline. Presentation of complete loss of vision after an isolated head trauma is very rare, and there are no similar cases in existing literature. The limits of surgical indications for depressed skull fractures are well established in neurosurgical practice. Surgical intervention should be performed immediately, especially in cases where neurological changes develop in the earliest stages after a trauma. The patient underwent emergency surgery to correct the blindness without affecting the vascular neighborhood. The depressed cranium was raised to its original position. The blindness had completely resolved shortly after the patient woke up during the postoperative period.

Bioccipital Lobe Hypoperfusion and Anton's Syndrome Resolution with Intravenous Thrombolysis.

BACKGROUND: Anton's syndrome is a rare neurological disorder characterized by a combination of visual anosognosia and confabulation of visual experience, most often seen after bilateral ischemic damage to the posterior occipital cortex. CASE REPORT: We report the first case of an acute synchronous P2 occlusion as confirmed by multiparametric computed tomography (CT) including perfusion. After the administration of Recombinant tissue plasminogen activator (rtPA), Anton's syndrome completely resolved. CONCLUSION: Multiparametric CT imaging may aid in quickly proving the underlying stroke in Anton's syndrome, especially helpful considering the discrepancy between the patient's perception and clinical examination results.

[Cortical blindness as initial manifestation of nonbacterial thrombotic endocarditis]. / Ceguera cortical como manifestación inicial de endocarditis trombótica no bacteriana.

Nonbacterial thrombotic endocarditis, formerly known as marantic endocarditis, it is an infrequent entity in which sterile, fibrin vegetations develop on heart valve leaflets. It is often diagnosed at the time of autopsy or in latestage malignancies. The most common malignancies associated with nonbacterial thrombotic endocarditis are lung, pancreatic, gastric cancer and adenocarcinomas of an unknown primary site. Diagnosis requires ruling out infective endocarditis and establishing the presence of valvular vegetations using echocardiography. We report the case of a patient with a recent diagnosis of advanced gastric adenocarcinoma who presented with cortical blindness. The computed tomography was compatible with cerebral ischemia. The transoesophageal echocardiogram showed two vegetations in mitral valve. Blood cultures were negative. We emphasize the importance of suspecting nonbacterial thrombotic endocarditis in patients with cancer and systemic embolism.

Patterns of Cortical Visual Field Defects From Embolic Stroke Explained by the Anastomotic Organization of Vascular Microlobules.

The cerebral cortex is supplied by vascular microlobules, each comprised of a half dozen penetrating arterioles that surround a central draining venule. The surface arterioles that feed the penetrating arterioles are interconnected via an extensively anastomotic plexus. Embolic occlusion of a small surface arteriole rarely produces a local infarct, because collateral blood flow is available through the vascular reticulum. Collateral flow also protects against infarct after occlusion of a single penetrating arteriole. Cortical infarction requires blockage of a major arterial trunk, with arrest of blood flow to a relatively large vascular territory. For striate cortex, the major vessels compromised by emboli are the inferior calcarine and superior calcarine arteries, as well as the distal branches of the middle cerebral artery. Their vascular territories have a fairly consistent relationship with the retinotopic map. Consequently, occlusion by emboli results in stereotypical visual field defects. The organization of the arterial supply to the occipital lobe provides an anatomical explanation for a phenomenon that has long puzzled neuro-ophthalmologists, namely, that of the myriad potential patterns of cortical visual field loss, only a few are encountered commonly from embolic cortical stroke.

Posterior reversible encephalopathy syndrome complicating diabetic ketoacidosis; an important treatable complication.

Development of acute neurological symptoms secondary to cerebral oedema is well described in diabetic ketoacidosis (DKA) and often has a poor prognosis. We present the clinical and radiological data of a 17-yr-old girl who developed cortical blindness, progressive encephalopathy, and seizures caused by posterior reversible encephalopathy syndrome (PRES) that developed after her DKA had resolved. Vasogenic oedema in PRES resolves if the underlying trigger is identified and eliminated. In this case, hypertension was identified as the likely precipitating factor and following treatment her vision and neurological symptoms rapidly improved. We suggest how recent DKA may have contributed to the development of PRES in this patient.

Olfactory Groove Meningiomas: Acute Presentation and Potential : Pitfalls in Management and Functional Restoration.

Meningiomas are typically benign, slow-growing lesions that present after an insidious onset of symptoms related to mass effect. The acute presentation of a patient who has suffered a transtentorial herniation event due to a meningioma is rare. There are only few publications describing such a presentation in the absence of hemorrhage [1]. In this case report, a patient with an olfactory groove meningioma presenting with signs and symptoms of transtentorial herniation in the absence of tumor-associated hemorrhage is discussed. This is a unique presentation of such a lesion. The patient developed Anton's syndrome-binocular visual loss with blindness denial. Management considerations for patients with meningiomas that present with acute deterioration are discussed.

Multidisciplinary Approach to Complicated Pregnancy.

A nulliparous pregnant woman in her mid-20s and in the 32nd week of gestation presented to the emergency department with severe headache and vomiting. She had an uneventful medical history; however, the physical examination upon hospital admission revealed a hypertensive emergency, papilledema, and 2+ dipstick proteinuria. Upon establishing the diagnosis of preeclampsia, aggressive therapy with corticosteroids, antihypertensive medication, and seizure prophylaxis was initiated. Hemodynamic stability was achieved within 24 hours and the patient remained in the observation unit located within the gynecology clinic. On the ninth day postadmission, however, her condition abruptly deteriorated and advanced to imminent eclampsia, accompanied by transient vision loss, altered mental status, and acute hypertensive crisis. After the patient underwent successful emergent delivery via caesarean section, a laboratory workup revealed hemolysis, elevated liver enzymes, and low platelet count, suggesting HELLP syndrome, a serious complication of eclampsia. This patient concurrently developed posterior reversible encephalopathy syndrome, which was confirmed by magnetic resonance imaging and acute respiratory distress syndrome (the latter presented with diffuse bilateral infiltrates on x-ray and developing pulmonary edema in the absence of cardiac etiology). Because of these life-threatening dynamics, the patient was transferred to the intensive care unit for further treatment. This case is a rare cascade of life-threatening complications that developed in a patient and required skillful multidisciplinary decision making and experienced management within an acute critical care setting. The final outcome of the treatment and intensive care was successful because both the patient and child survived and had no chronic or debilitating sequelae.

Cortical Blindness in a Child Secondary to Mycoplasma pneumoniae Infection.

Our objective is to present a case of an uncommon complication associated with Mycoplasma pneumoniae infection in a child where cortical blindness was the main clinical feature. Stroke due to an infection by M. pneumoniae is very uncommon. No consensus has been reached on the pathogenesis, although several pathogenic mechanisms have been proposed. Occlusion of posterior cerebral circulation is the most uncommon central nervous system complication of M. pneumoniae infection being reported. Symptoms are usually hemiplegia and dysarthria. We report a case of a 6-year-old boy who suffered cortical blindness due to a stroke 2 days after M. pneumoniae infection. This is the first case of documented cortical blindness due to posterior cerebral arteries occlusion in children after M. pneumoniae infection.

Reversible blindness and preeclampsia.

Neurological manifestations of preeclampsia are serious and very variable. We report the case of a woman at 34 weeks gestation with preeclampsia who developed blindness within hours without alteration of consciousness. The imagery was in favor of posterior reversible encephalopathy. The therapeutic management consisted of emergency fetal extraction, the administration of antihypertensive drugs and magnesium sulfate. The outcome was favorable with complete recovery of visual function. This case reflects the heterogeneity of the clinical presentation of preeclampsia, as the only neurological manifestation was cortical blindness, with no associated consciousness disorder.