Orbital metastases.

BACKGROUND: Orbital metastasis, although uncommon, is a condition optometrists should consider in a patient presenting with proptosis, ptosis, diplopia, or a lid mass with a history of cancer. However, in as many as 19% of cases, patients have no prior or concurrent history of systemic cancer when presenting with ophthalmic symptoms. If suspecting an orbital metastasis, neuroimaging is important, as well as a referral to the patient's primary care provider, oncologist, and ophthalmologist. CASE REPORTS: Three patients with orbital metastasis are discussed. The first was a 55-year-old white man who initially presented with a left ptosis of unclear etiology. Magnetic resonance imaging of his orbits and an orbital biopsy found metastatic esophageal adenocarcinoma. Radiotherapy and chemotherapy were initiated, but the patient died shortly afterward. The second patient was a 49-year-old black man who also presented with a ptosis of the right upper eyelid. An area of the retina appeared elevated; ophthalmic B-scan and computed tomography of the orbits confirmed the presence of a mass, determined to be metastatic lung carcinoma to the right orbit. A course of radiotherapy was initiated, but the patient died 3 days after completing therapy. The last case was a 77-year-old white man with a history of metastasis to the left orbit from non-Hodgkin's lymphoma. On examination, he had proptosis of the left eye, initially thought to be caused by a recurrence of the metastasis. However, a computed tomography scan showed a new meningioma in the same orbit, and treatment was started. The proptosis improved, and the patient continues to be followed up regularly. CONCLUSIONS: Any patient with proptosis and/or ptosis with a history of cancer should be evaluated for orbital metastasis. Optometrists should keep in mind that an orbital metastasis may represent the initial manifestation of undiagnosed systemic cancer. Prognosis can be poor, and thus treatment is sometimes palliative in nature, intending to slow the progression of the disease instead of providing a cure.

On the frontline: what an optometrist needs to know about myasthenia gravis.

BACKGROUND: Myasthenia gravis (MG) is an autoimmune disease that affects the voluntary skeletal muscles. It is characterized by transient weakness of the muscles that improves with rest. Muscle weakness involving the eyes can produce signs or symptoms of diplopia, blurred vision, ptosis, and ophthalmoplegia. Ptosis is defined as an abnormal eyelid "drooping" beyond the normal 1 to 2 mm of the upper limbus of the cornea. Hence, most patients with MG have ophthalmic manifestations. Among all patients with MG, up to half will have exclusively ocular symptoms. In these cases, the condition is referred to as ocular myasthenia. CASE REPORT: A 60-year-old man was referred from a neurology clinic for management of intermittent diplopia for greater than 1 year and intermittent bilateral ptosis for the prior year. He reported that he first noticed symptoms of MG at the age of 42, but did not receive the diagnosis until 1 year before his aforementioned neurology examination. He was prescribed spectacles with bilateral ptosis crutches. A diagnosis of severe seronegative MG was subsequently confirmed with neurologic examination and antibody testing. CONCLUSIONS: Because patients with undiagnosed myasthenia gravis may present initially with ocular signs or symptoms, it is important for the optometrist to be familiar with the condition and the simple "in-office" tests that can be performed to establish a tentative diagnosis and management plan. The optometrist can also participate in the management of ocular manifestations of myasthenia and should be familiar with the use of a ptosis crutch (in addition to prism spectacles or occlusion therapies if indicated) as a nonsurgical intervention for ptosis.

Palinopsia.

BACKGROUND: Palinopsia is a visual phenomenon that has been associated with brain neoplasia, epilepsy, trauma, systemic disease, psychiatric illness, and illicit as well as prescribed drug use. Despite some resemblance to diplopia, polyopia, and physiologic afterimage formation, palinopsia is actually a distinct entity often suggestive of disease through its distinct signs and symptoms. Careful patient history, visual field testing, and neuroimaging are among the tools used to diagnose palinopsia. CASE REPORTS: Four case reports of patients with palinopsia are presented. With the first patient, the palinopsia was associated with extensive lysergic acid diethylamide (LSD) use. The second patient's palinopsia was determined to be secondary to head trauma from a motor vehicle accident. The third patient began to experience palinopsia after he had been prescribed trazodone for insomnia. The fourth patient was found to have multiple potential etiologies. These 4 unique patients highlight the causes and management of palinopsia. CONCLUSIONS: Optometrists should be aware of the symptoms of palinopsia to enable them to recognize this phenomenon and minimize the chance of misdiagnosis. Learning the physiologic mechanisms behind this uncommon disorder can help the clinician correctly identify its cause. Although palinopsia itself is not a disease, it is indicative of a disease, and the symptoms of palinopsia may be a manifestation of a serious underlying systemic dysfunction that could warrant treatment. In addition, identifying the symptoms of palinopsia can put patients at ease with regard to the often disturbing visual symptoms.

Functional vision loss: a diagnosis of exclusion.

BACKGROUND: Most cases of visual acuity or visual field loss can be attributed to ocular pathology or ocular manifestations of systemic pathology. They can also occasionally be attributed to nonpathologic processes or malingering. Functional vision loss is any decrease in vision the origin of which cannot be attributed to a pathologic or structural abnormality. CASE REPORTS: Two cases of functional vision loss are described. In the first, a 58-year-old man presented for a baseline eye examination for enrollment in a vision rehabilitation program. He reported bilateral blindness since a motor vehicle accident with head trauma 4 years prior. Entering visual acuity was "no light perception" in each eye. Ocular health examination was normal and the patient made frequent eye contact with the examiners. He was referred for neuroimaging and electrophysiologic testing. The second case was a 49-year-old man who presented with a long history of intermittent monocular diplopia. His medical history was significant for psycho-medical evaluations and a diagnosis of factitious disorder. Entering uncorrected visual acuities were 20/20 in each eye, but visual field testing found constriction. No abnormalities were found that could account for the monocular diplopia or visual field deficit. A diagnosis of functional vision loss secondary to factitious disorder was made. CONCLUSIONS: Functional vision loss is a diagnosis of exclusion. In the event of reduced vision in the context of a normal ocular health examination, all other pathology must be ruled out before making the diagnosis of functional vision loss. Evaluation must include auxiliary ophthalmologic testing, neuroimaging of the visual pathway, review of the medical history and lifestyle, and psychiatric evaluation. Comanagement with a psychiatrist is essential for patients with functional vision loss.

Sectoranopia: a stroke in the lateral geniculate nucleus or optic radiations?

BACKGROUND: The lateral geniculate nucleus (LGN) is the site at which ganglion cell axons of the optic tract synapse with neurons that form the optic radiations. Lesions of the perigeniculate visual pathway are characterized by distinct pupillary, visual field, and ophthalmoscopic findings. Such findings, combined with results from neuroimaging, enable one to precisely locate the area of the visual pathway that is involved. CASE REPORT: A patient who presented to our clinic with a complaint of narrowly missing several motor vehicle accidents recently was found to have a left horizontal sectoranopia on a screening visual field. Magnetic resonance imaging confirmed the presence of an old infarct involving the optic radiations. The patient's medical history was significant for high homocysteine levels that likely contributed to his having had several cerebral vascular accidents in the past, one of which affected the optic radiations. CONCLUSIONS: Damage to the LGN and optic radiations can produce sectoranopic visual field defects. Although it may not be possible to specify the exact location of a lesion, understanding the blood supply of the visual pathway and retinotopic organization of the LGN aids in the localization of infarcts that cause characteristic visual field defects.

Peripheral retinal neovascularization in talc retinopathy.

BACKGROUND: Neovascularization of the peripheral retina can be present in a number of systemic and ocular diseases. Very rarely, peripheral retinal neovascularization can also be manifested in intravenous drug abusers. In addition to ocular complications, intravenous drug abusers are at high risk for contracting various infections and the development of pulmonary and cardiovascular diseases. We present a case of a chronic heroin and cocaine abuser with bilateral peripheral retinal neovascularization, pulmonary complications, and a history of endocarditis. CASE REPORT: A patient with a 20-year history of heroin and cocaine abuse initially presented for a routine eye examination. Fundus examination revealed pinpoint white deposits centered in both maculas, engorged vascular fronds with a patch of intraretinal hemorrhage in the peripheral retinal of the right eye and neovascularization of the disc as well as exudation with adjacent focal preretinal hemorrhage in the left eye. The patient underwent fluorescein angiography and was screened for diabetes, sarcoidosis, and sickle cell disease. When no systemic disease could be discovered, it was concluded that the peripheral retinal neovascularization developed as a result of vascular occlusion from heroin and cocaine abuse. DISCUSSION: It is important to investigate the cause of neovascularization in the peripheral retina. Retinal vascular emboli such as talc are common in drug abusers, but in most cases, the retinal deposits pose only a minimal threat to vision. However, this case shows that careful retinal examination is warranted in drug abusers to rule out neovascularization of the retina. Other causes of peripheral retinal neovascularization should be ruled out as well. These conditions include sickle cell retinopathy, sarcoidosis, diabetic retinopathy, blood dyscrasias, retinal vascular occlusion, Eales' disease, and other systemic conditions, so that appropriate ocular and systemic treatment can be provided. Peripheral retinal neovascularization is best treated by pan-retinal photocoagulation.

Subclavian steal syndrome.

BACKGROUND: Subclavian steal syndrome is a systemic entity that is well-documented in the medical literature. It occurs when the subclavian artery becomes stenosed or occluded and blood flow is reversed in the ipsilateral vertebral artery. This siphoning or "stealing" of blood has traditionally been thought to cause symptoms of vertebral-basilar insufficiency. Recent literature indicates that subclavian steal syndrome is often asymptomatic, but may be associated with a wide variety of signs and symptoms of vertebro-basilar, carotid, or upper extremity ischemia, and that the manifestation of the condition is probably dependent on the patency of the other cranial arteries. CASE REPORTS: This report describes three patients who underwent comprehensive eye examinations and who had been previously diagnosed with subclavian steal phenomenon. The initial symptoms included: unilateral Hollenhorst plaque, unilateral fibrino-platelet plaque, and one patient with no symptoms These patients were followed for their ocular conditions concurrently with their physicians following their systemic circulatory disease. Signs and symptoms, imaging and laboratory tests, and management are discussed. CONCLUSIONS: Subclavian steal syndrome is a systemic condition that may manifest ocular signs and symptoms that optometrists should recognize, and which merits referral for systemic evaluation and treatment as necessary Patients who manifest signs and symptoms of vertebro-basilar insufficiency, carotid territory ischemia, or ocular symptoms of atherosclerosis may be diagnosed with subclavian steal syndrome as evaluation of the extracranial arteries is pursued.

Coloboma of the crystalline lens.

BACKGROUND: Anomalies of crystalline lens shape and position include: lenticonus, lentiglobus, microspherophakia, coloboma, and ectopia lentis. Lens coloboma probably results from a localized absence or maldevelopment of lens zonules. It may be a variant of nontraumatic (congenital) ectopia lentis, in which the zonular deficiency is more generalized. Coloboma of the lens and nontraumatic ectopia lentis may occur in association with other ocular and systemic anomalies. A case of lens coloboma is presented, and lens coloboma, ectopia lentis, and associated ocular and systemic conditions are reviewed. CASE REPORT: A 36-year-old man came to us for routine evaluation. He was found to be moderately myopic. Post-dilated biomicroscopy revealed a crystalline lens coloboma O.D. Since the patient was tall and thin, and his chest X-ray demonstrated abnormal cardiovascular findings, Marfan's syndrome or another connective tissue disorder was suspected. No definitive diagnosis was established for the patient, but he later reported that his sister had Marfan's syndrome, renewing suspicion that he also had the condition. He was advised to wear polycarbonate spectacles and to avoid contact sports. CONCLUSIONS: Coloboma of the crystalline lens and nontraumatic ectopia lentis may occur in isolation or with other ocular pathologies, and may reflect an underlying systemic disorder. Optometric management must address safety issues to reduce the risk of retinal detachment and lens dislocation. Systemic evaluation should be pursued to rule out Marfan's syndrome and similar disorders. Genetic investigation and evaluation of family members may also be merited.

Acquired Horner's syndrome: clinical review.

BACKGROUND: Horner's syndrome results from disruption of the sympathetic innervation to the eye anywhere along its three-neuron circuit. It is essential to be familiar with the oculosympathetic pathway, the structures that are in close proximity to it, and the disease processes that may interrupt it when an evaluation is made of an acquired Horner's syndrome, since it may be a manifestation of a life-threatening condition. CASE REPORTS AND DISCUSSION: Four patients with acquired Horner's syndrome resulting from various etiologies are presented. The first case is that of a 41-year-old man with a history of central retinal artery occlusion and Horner's syndrome caused by an internal carotid dissection. The second patient, a 51-year-old man with a Pancoast tumor, initially went to his chiropractor with sympyoms of weakness and pain in the upper extremity. The third case involves a 49-year-old woman with an enlarged thyroid gland. The fourth patient is a 70-year-old man with a history of a stellate ganglionectomy. The sympathetic pathway to the eye, its anatomical correlates, pharmacologic testing, and the systemic diseases that may cause Horner's syndrome are reviewed. CONCLUSION: Familiarity with the sympathetic pathway to the eye and its anatomical relationships enables one to understand the mechanism by which a Horner's syndrome has developed.

Parieto-occipital arteriovenous malformation.

BACKGROUND: Arteriovenous malformation (AVM) in the occipital lobe has been known to cause visual symptoms and headaches. Arteriovenous malformation is a congenital anomaly that consists of abnormal arteries and veins without the presence of a capillary bed. The majority of patients initially manifest intracranial hemorrhage, while others manifest symptoms of seizures, headaches, and progressive neurological deficits. CASE REPORTS: A 45-year-old man was referred for a baseline threshold visual field before neurosurgery for his arteriovenous malformation. The patient's medical history included seizures with visual aura. The seizures were originally attributed to alcohol withdrawal; later, he was diagnosed with a right parietooccipital AVM. Optometric examination revealed an incomplete left inferior homonymous quadranopsia. He subsequently had the embolization and resection procedures for his AVM. Seizures and visual aura symptoms terminated after AVM surgery; the visual field defect increased slightly in extent. Two additional cases are presented to highlight some common characteristics-as well as the variability-in cerebral AVMs. The second case involves a 47-year-old man with a history of left frontal lobe AVM resection 7 years earlier and headaches. The third case is that of a 60-year-old man with a large left parietal lobe AVM with seizures who is anticipating neurosurgery. CONCLUSION: Clinical differentiation of migraine from arteriovenous malformation is often regarded as difficult, since both conditions may manifest similar features of visual aura, with or without headaches. Early diagnosis and treatment of AVM may reduce the risk of serious complications. When a patient manifests alarming headaches with or without visual aura, neuro-imaging workup is warranted to rule out sinister causes.