Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Decreased visual acuity and loss of visual ability are devastating anesthetic and surgical complications. The incidence is greater in patients with preexisting hypertension, diabetes, sickle cell anemia, renal failure, gastrointestinal ulcer, narrow-angle glaucoma, vascular occlusive disease, cardiac disease, arteriosclerosis, polycythemia vera, and collagen vascular disorders. Precipitating factors for ischemic optic neuropathy include prolonged hypotension, anemia, surgery, trauma, gastrointestinal bleeding, hemorrhage, shock, prone position, direct pressure on the globe, and long operative times. Prone and Trendelenburg positions can lead to visual loss related to decreased venous return from the head. Visual impairment may result from increased intracranial pressure, which contributes to undue pressure on the optic nerve. The prone position increases the risk of direct compression injury to the orbit and corneal abrasion. Astute attention to positioning is imperative, especially with the prone position. At-risk patients should receive transfusion once the calculated allowable blood loss has been surpassed. Unacceptable hemoglobin and hematocrit values should be corrected preoperatively and levels monitored during the case to avoid intraoperative anemia in at-risk patients. The blood pressure of patients with predisposing diseases should be kept within normal limits. To avoid this devastating complication, it is imperative that anesthesia providers understand contributing factors and prevention strategies.
 ...
PMID:Visual loss as a complication of nonophthalmologic surgery: a review of the literature. 1563 61

Four patients (age range 54-82, 1F 3M) diagnosed with non-arteritic ischemic optic neuropathy experienced acute worsening of visual function after instillation of phenylephrine for dilated funduscopic examination. They experienced decreased visual function immediately or shortly after administration of topical mydriatic drops given in preparation for funduscopy. In all cases one drop each of 2.5% phenylephrine and 0.5-1% tropicamide was used. Three patients had classical risk factors such as hypertension, diabetes, and had a contralateral "disc-at-risk". The female and youngest patient had ischemic optic neuropathy presumed secondary to lupus erythematosus. The time from acute visual loss to presentation to neuro-ophthalmic care ranged from 1-6 days. The time of onset of the decline in visual function varied from 45 minutes (patient with lupus) to 12 hours after instillation of mydriatic drops. Visual acuity at diagnosis ranged from 20/40-20/400. Phenylephrine is a mydriatic with vasoconstrictive properties, which may be absorbed through the cornea, thus yielding non-negligible intraocular concentrations. Vasoconstriction of the watershed posterior ciliary capillary beds may result in further precipitating infarction of already compromised circulatory territories in edematous optic nerves. Because phenylephrine is a known vasoconstrictor in vivo and in vitro, it is more likely to cause deleterious vasoconstriction and an acute decline in visual function in patients with acute ischemic optic neuropathy than tropicamide. The routine practice of using phenylephrine to prepare patients for funduscopic assessment should be re-examined, particularly in patients with ischemic optic neuropathy.
 ...
PMID:Topical phenylephrine may result in worsening of visual loss when used to dilate pupils in patients with vaso-occlusive disease of the optic nerve. 1551 9

Nonarteritic anterior ischemic optic neuropathy is a common cause of sudden, painless loss of vision present commonly on awakening from sleep. It most commonly affects middle-aged and elderly Caucasian men and women. Involvement of the opposite eye occurs within 3 years in less than 43% of patients. Hypertension, diabetes, and nocturnal hypotension are risk factors. A congenital small cup-to-disk ratio also predisposes to the optic nerve ischemia. There is no effective therapy to treat patients acutely or to prevent recurrence. After 6 months of careful follow-up, 57.3% of patients will have no significant change or worsening of their vision in the involved eye.
 ...
PMID:Nonarteritic anterior ischemic optic neuropathy. 1572 60

Seven patients, aged between 50 and 69 years, had typical features of nonarteritic anterior ischemic optic neuropathy (NAION) within 36 hours after ingestion of sildenafil citrate (Viagra) for erectile dysfunction. Six patients had vision loss within 24 hours after use of the agent. Final visual acuity in the affected eye ranged from 20/20 to light perception. Both eyes were affected in one individual. All affected individuals had pre-existing hypertension, diabetes, elevated cholesterol, or hyperlipidemia. Seven similar cases have been previously reported. Sildenafil may provoke NAION in individuals with an arteriosclerotic risk profile.
 ...
PMID:Nonarteritic ischemic optic neuropathy developing soon after use of sildenafil (viagra): a report of seven new cases. 1651 58

Decreased visual acuity and loss of visual ability are devastating anesthetic and surgical complications. The incidence is greater in patients with preexisting hypertension, diabetes, sickle cell anemia, renal failure, gastrointestinal ulcer, narrow-angle glaucoma, vascular occlusive disease, cardiac disease, arteriosclerosis, polycythemia vera, and collagen vascular disorders. Precipitating factors for ischemic optic neuropathy include prolonged hypotension, anemia, surgery trauma, gastrointestinal bleeding, hemorrhage, shock, prone position, direct pressure on the globe, and long operative times. Prone and Trendelenburg positions can lead to visual loss related to decreased venous return from the head. Visual impairment may result from increased intracranial pressure, which contributes to undue pressure on the optic nerve. The prone position increases the risk of direct compression injury to the orbit and corneal abrasion. Astute attention to positioning is imperative, especially with the prone position. At-risk patients should receive transfusion once the calculated allowable blood loss has been surpassed Unacceptable hemoglobin and hematocrit values should be corrected preoperatively and levels monitored during the case to avoid intraoperative anemia in at-risk patients. The blood pressure of patients with predisposing diseases should be kept within normal limits. To avoid this devastating complication, it is imperative that anesthesia providers understand contributing factors and prevention strategies.
 ...
PMID:Visual loss as a complication of non-ophthalmic surgery: a review of the literature. 1594 13

A 34-year-old obese woman developed blurred vision in both eyes soon after large-volume liposuction of the dorsum and gluteus region bilaterally associated with abdominal dermolipectomy. An ophthalmic examination revealed severe bilateral visual loss and pallid optic disc edema. The patient gave a history of transient obscurations of vision in the past. Neuroimaging studies were non-revealing, but a lumbar puncture disclosed a markedly elevated intracranial pressure. The patient was diagnosed as having had bilateral ischemic optic neuropathy superimposed on pre-existing idiopathic intracranial hypertension (IIH). Acetazolamide treatment was used. Some visual improvement occurred, and optic disc edema evolved into severe optic disc pallor. This case shows that visual loss from optic disc infarction may be a devastating complication of high-volume liposuction in patients with underlying IIH. Because liposuction is frequently performed on obese patients, physicians should screen for signs and symptoms of IIH before undertaking this procedure.
 ...
PMID:Bilateral visual loss complicating liposuction in a patient with idiopathic intracranial hypertension. 1651 64

Ischemic optic neuropathy is a common cause of visual loss in the older population. This disease is classified into anterior and posterior type according to the location the lesions. The anterior type is due to transient nonperfusion or hypoperfusion of the ciliary circulation in the optic nerve head. The etiology of this disease is multifactorial. The most important risk factors for developing anterior ischemic optic neuropathy (AION) include hypertension, nocturnal hypotension, diabetes mellitus, atherosclerosis and small cup in the optic disc. AION presents with sudden painless loss of vision, pale edema of the optic disc, afferent papillary defect and visual field defects, typically in lower quadrants. Posterior ischemic optic neuropathy (PION) is a rare condition and diagnosis of it usually is made only after other causes of a retrobulbar optic neuropathy have been excluded. There are three distinct subtype of PION: perioperative, arteritic and nonarteritic. They are characterized by acute visual loss, variable visual field defects, relative afferent pupillary defect and normal optic disc.
 ...
PMID:[Ischemic optic neuropathy. Pathogenesis, clinical features, diagnostics and treatment]. 1702 4

Sudden, painless visual loss occurs in retinal disorders that stem from primary ocular as well as systemic diseases. Vascular insufficiency is one of the leading causes of sudden painless unilateral loss of vision. Early recognition of ischemic optic neuropathy, and rapid correction of hypotension, might improve the recovery from ischemic optic neuropathy. The case of a 40-year-old man who, after antihypertensive therapy for malign hypertension, developed sudden, painless loss of vision in both his eyes is discussed.
 ...
PMID:Sudden painless visual loss after initiation of antihypertensive therapy: case report. 1796 3

A 76 year-old man had had hypertension, diabetes mellitus and hyperlipidemia since 1985, and bruit in his left neck since 1993. He had abrupt decrease in left visual acuity on November 24, 2005, and visited an ophthalmologist. On November 28, his corrected visual acuity was 1.0 in the right and 0.1 in the left. The examination of optic fundi showed ear-side edema of the left optic disk. Fluorescence examination of the left optic fundus showed delay in early filling and later hyperfluorescence. Goldman visual field examination showed horizontal lower semiblindness. Since he did not complain of eye pain, his blood examination showed no reaction of inflammation, and he had hypertension, diabetes mellitus and hyperlipidemia, anterior ischemic optic neuropathy was diagnosed. The treatment with aspirin, alprostadil and prednisolone transiently improved the optic fundi and visual acuity, but his left visual acuity returned to 0.1. Carotid ultrasonography showed 95 percent stenosis in the left internal carotid artery. As there is no established treatment for ischemic optic neuropathy, the management of risk factors is most important.
 ...
PMID:[A case of nonarteritic anterior ischemic optic neuropathy with hypertension, diabetes mellitus, hyperlipidemia and severe stenosis of the internal carotid artery]. 1833 80

In this prospective study, we report fifty consecutive cases of bilateral papilledema without neurosurgical or obvious ophthalmologic etiology, referred to our institution between January 2005 and March 2007. Lumbar puncture with opening CSF pressure measurement distinguished two groups of patients: Group 1 (n=39) with and Group 2 (n=11) without intracranial hypertension. In Group 1, 9/39 patients presented secondary intracranial hypertension mainly due to cerebral venous thrombosis. In 30 patients, after complete investigations, a diagnosis of idiopathic intracranial hypertension was made: as commonly reported, patients were predominantly overweight (96.7% with body mass index>25kg/m2) young (mean age=27.6 years) and women (96.7%). Eleven patients with intracranial hypertension had no headaches. In Group 2, the most common diagnosis was bilateral non-arteritic anterior ischemic optic neuropathy, but rare causes have been identified.
 ...
PMID:[Bilateral papilledema: prospective study of fifty patients]. 1834 56


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>