Abstract：
:The determination of average net pulsatile ocular blood flow form measurements of the intraocular pressure (IOP) pulse is based upon 1) an accurate measurement of IOP and its time variation; 2) a knowledge of the relation between the volume of the living eye and its IOP; 3) a physical model for the flow of blood through the eye: and 4) a concept of steady venous outflow from the eye. Each of these premises needs to be examined. The present analysis assesses the validity of the pneumatic tonometer for measuring the pressure in a flowing column of gas that is directed toward a thin membrane that is in contact with the surface of the cornea. The pressure of this stream of gas exerts a force against the cornea that depresses the corneal surface against the opposing force of the IOP. The balance of these forces and the resultant effect on the tonometer pressure sensor is described by the theories of elasticity, thermodynamics and fluid mechanics. In this treatment, differential equations are solved for the elastic deflections of the cornea subject to the opposing intraocular and tonometer pressures. This permits the pressure in the chamber of the pneumatic tonometer to be related through first principles to the IOP. The response of the tonometer pressure sensor to a range of IOPs (5-60 mmHg) is obtained, as well as the dynamical response of the tonometer to IOP oscillations. The conclusion is that the pneumatic tonometer provides a high fidelity, noninvasive measure of the IOP and its time variation.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Surv Ophthalmoljournal_title
Survey of ophthalmologyauthors
Silver DM,Farrell RAdoi
10.1016/0039-6257(94)90049-3subject
Has Abstractpub_date
1994-05-01 00:00:00pages
S72-80eissn
0039-6257issn
1879-3304pii
0039-6257(94)90049-3journal_volume
38 Supplpub_type
杂志文章,评审abstract：:An elderly woman presented for evaluation of the recent onset of a fixed, blurry circle in the right eye. Visual acuity was 20/20 OU. Funduscopic examination revealed a newly-noticed isolated cotton-wool spot in each eye. Amsler grid testing revealed an arcuate shady area in the inferior nasal field. A thorough system...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/s0039-6257(96)80072-5
更新日期：1996-03-01 00:00:00
abstract：:The clinical syndrome of divergence paralysis has been described since the mid 19th century. Speculation still surrounds the possible existence of an anatomical center for divergence function. Our report explores this possibility and describes the magnetic resonance images of a patient with a unilateral 6th nerve pals...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(86)90094-9
更新日期：1986-05-01 00:00:00
abstract：:Ocular myasthenia is a localized form of myasthenia clinically involving only the extraocular, levator palpebrae superioris, and/or orbicularis oculi muscles. Ocular manifestations can masquerade as a variety of ocular motility disorders, including cranial nerve and gaze palsies. A history of variable and fatiguable m...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/0039-6257(94)90194-5
更新日期：1994-11-01 00:00:00
abstract：:The published evidence that instilled drugs can affect the blood supply to the retina and optic nerve head in humans is examined. As a background, seven techniques that have been used to measure flow are briefly described and criticized. For timolol, the corresponding measurements, obtained by a number of investigator...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/s0039-6257(02)00326-0
更新日期：2002-08-01 00:00:00
abstract：:Electrophysiological research on acquired retinal disorders, both common and rare, is reviewed. Age is a major factor influencing electroretinogram (ERG) and electro-oculogram (EOG) findings. Bipolar or Müller cell death in the aging retina could account for much of the amplitude decline that is observed with age. In ...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/s0039-6257(00)00125-9
更新日期：2000-07-01 00:00:00
abstract：:Optic nerve hemangioblastoma is a rare tumor that is usually unilateral and most commonly occurs in the context of von Hippel-Lindau disease. Differential diagnosis is based on clinical history and imaging. Magnetic resonance imaging with gadolinium enhancement is the most useful imaging modality as it can reveal flow...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/j.survophthal.2018.10.002
更新日期：2019-01-01 00:00:00
abstract：:The need of blood flow to different organs varies rapidly over time which is why there is sophisticated local regulation of blood flow. The term dysregulation simply means that blood flow is not properly adapted to this need. Dysregulative mechanisms can lead to an over- or underperfusion. A steady overperfusion may b...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/j.survophthal.2007.08.010
更新日期：2007-11-01 00:00:00
abstract：:Two short visual field tests were performed on 106 subjects approximately 5 minutes apart with or without a hand vibration stimulus between the field tests. There were 31 eyes in the control group (10 without glaucoma, eight glaucoma suspects, 10 with primary open-angle glaucoma, and three with secondary open-angle gl...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/s0039-6257(99)00051-x
更新日期：1999-06-01 00:00:00
abstract：:With an occurrence of approximately 1 in 3000 births, von Recklinghausen neurofibromatosis (NF) is one of the most common inherited human disorders. NF is considered a neurocristopathy, a disorder of neural crest derived cells. One of the complications of NF is the development of neural crest derived malignancies such...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/0039-6257(89)90014-3
更新日期：1989-03-01 00:00:00
abstract：:A 20-year-old Hispanic man with Down syndrome presented with progressively worsening headache, fluctuating decreased vision, and bilateral optic disk edema. Magnetic resonance imaging of the head showed an empty sella, and magnetic resonance venography showed thrombosis of left transverse and sigmoid sinuses. Catheter...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/j.survophthal.2012.10.005
更新日期：2013-11-01 00:00:00
abstract：:The painting Rubens Peale with a Geranium (1801), by Rembrandt Peale, has earned a reputation as a masterpiece of early American portraiture. In recent years the painting has also been the source of controversy, because Rubens was depicted with two pairs of eyeglasses at a time when most people would not have been por...
journal_title：Survey of ophthalmology
pub_type： 传,历史文章,杂志文章
doi：10.1016/s0039-6257(97)00008-8
更新日期：1997-03-01 00:00:00
abstract：:The development of nuclear magnetic resonance imaging techniques provides the physician with a non-invasive means of obtaining anatomic, physiologic and biochemical information about neuro-ophthalmic disorders. The authors summarize the principles of nuclear magnetic resonance imaging and present a case report illustr...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(84)90116-4
更新日期：1984-07-01 00:00:00
abstract：:A 38-year-old woman presented with bilateral optic neuropathy, leg weakness, and urinary symptoms. Despite her spinal MR being normal, her serum was positive for NMO-IgG. This indicated that she likely had Devic disease. ...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/j.survophthal.2007.10.002
更新日期：2008-01-01 00:00:00
abstract：:Phosphorus (31P) nuclear magnetic resonance (NMR) represents a noninvasive technique for the assessment of ocular metabolism. The measurement of a spectrum of phosphorus-containing metabolites (e.g., phosphorylated sugars and ATP), including a number of heretofore uncharacterized metabolites, can be made with a single...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(85)90063-3
更新日期：1985-11-01 00:00:00
abstract：:The clinical and histopathologic features of Axenfeld's anomaly and Rieger's anomaly and syndrome are reviewed, and recent findings regarding the pathogenesis of this spectrum of developmental disorders are discussed. Based on these observations, it has been suggested that a developmental arrest, in the third trimeste...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/0039-6257(85)90205-x
更新日期：1985-05-01 00:00:00
abstract：:Recent advances in our understanding of the anatomy and physiology of accommodation have contributed to current concepts of the possible constituent factors in presbyopia, largely supplanting the long-held belief that presbyopia is due to sclerosis of the crystalline lens. In this review, the author examines epidemiol...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/0039-6257(89)90126-4
更新日期：1989-07-01 00:00:00
abstract：:A 63-year-old man developed bilateral conjunctival injection and irritation followed by periocular discomfort and diplopia. Within weeks left proptosis and intermittent fever were noted. Orbital CT scan showed bilateral nodular enlargement of multiple extraocular muscles. Fine needle aspiration biopsy of the extraocul...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(88)90087-2
更新日期：1988-11-01 00:00:00
abstract：:The choroid is the vascular coat of the eye, and its role has been studied in multiple chorioretinal disorders. Recent advancements in choroidal imaging techniques, including enhanced depth imaging optical coherence tomography, swept source optical coherence tomography, en face optical coherence tomography, and optica...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/j.survophthal.2018.11.002
更新日期：2019-01-01 00:00:00
abstract：:The ocular posterior segment manifestations of AIDS may be divided into four categories: retinal vasculopathy, unusual malignancies, neuro-ophthalmologic abnormalities, and opportunistic infections. Microvasculopathy is the most common manifestation. Opportunistic infections, particularly cytomegalovirus retinitis and...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/j.survophthal.2003.12.008
更新日期：2004-03-01 00:00:00
abstract：:The court decisions included in this article reflect judicial attitudes towards medicolegal cases in most states. The courts have defined and amplified issues of informed consent, the physician's duty to warn patients and protect third parties, the limitations of the "Good Samaritan" statute, the responsibility of the...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(87)90071-3
更新日期：1987-07-01 00:00:00
abstract：:The Polymerase Chain Reaction (PCR) is a highly innovative technique which allows for the generation of large amounts of DNA starting from minute quantities obtained from the blood or tissue of a patient. With the increasing knowledge concerning the structure of the human genome and the potential to amplify specific s...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/s0039-6257(96)00004-5
更新日期：1997-01-01 00:00:00
abstract：:Glaucoma is often characterized by decreased pressure-sensitive aqueous outflow through the trabecular meshwork. This defect in pressure-sensitive aqueous outflow is evident from the low tonographic facility of outflow ("C") measured in many patients. The impairment in outflow facility causes the high intraocular pres...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/s0039-6257(03)00003-1
更新日期：2003-04-01 00:00:00
abstract：:A child with interstitial deletion of chromosome 17, right optic nerve hypoplasia, and impaired speech had bilateral congenital optic disc pigmentation, giving the appearance of gray optic discs. This appearance did not change over a period of two-and-a-half years. Previous cases of gray optic discs in neonates have b...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/0039-6257(89)90013-1
更新日期：1989-03-01 00:00:00
abstract：:In the present study the relationship between intraocular pressure (IOP) and pulsatile ocular blood flow (POBF) in low tension glaucoma (LTG) has been investigated. The POBF was measured using the Ocular Blood Flow system of Langham in undisturbed eyes and repeated at IOP increments of about 5 and 10 mmHg in 20 patien...
journal_title：Survey of ophthalmology
pub_type： 临床试验,杂志文章
doi：10.1016/0039-6257(94)90064-7
更新日期：1994-05-01 00:00:00
abstract：:Age-related macular degeneration (AMD) is one of the leading causes of blindness worldwide with increasing prevalence owing to increased life expectancy. Intravitreal injections of antivascular endothelial growth factor agents are commonly used in exudative AMD and oral antioxidant medication for nonexudative AMD; how...
journal_title：Survey of ophthalmology
pub_type： 杂志文章,评审
doi：10.1016/j.survophthal.2020.08.005
更新日期：2020-09-21 00:00:00
abstract：:The growth of the eye results in a myopic shift in aphakic and pseudophakic eyes during childhood. Cataract surgery after the age of 6 months, with or without lens implantation, appears to have little effect on the rate of refractive growth. Most children with pseudophakia have a large amount of myopic shift. This myo...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/j.survophthal.2009.07.001
更新日期：2010-03-01 00:00:00
abstract：:For 11 years, a 50-year-old woman with euthyroid Graves' disease experienced intermittent exacerbations of her orbitopathy associated with a decline in visual acuity. On each occasion, treatment with systemic corticosteroids led to prompt recovery of vision. Upon referral for consideration for orbital decompressive su...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/s0039-6257(97)00094-5
更新日期：1997-11-01 00:00:00
abstract：:Idiopathic central serous chorioretinopathy (ICSC) is a localized detachment of the sensory retina in the macula which is commonly seen by the general ophthalmologist. However, ICSC with bullous retinal detachment is a rare disease characterized by extensive sensory retinal detachment of the posterior pole and elsewhe...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/0039-6257(86)90036-6
更新日期：1986-11-01 00:00:00
abstract：:Retinitis pigmentosa (RP) is a form of inherited night blindness. Over decades, various dubious treatment strategies that lacked sufficient theoretically sound underpinnings were explored. Initially they were enthusiastically promoted and subsequently discredited. It is apparent that many were predicated on the errone...
journal_title：Survey of ophthalmology
pub_type： 历史文章,杂志文章
doi：10.1016/j.survophthal.2013.04.002
更新日期：2013-11-01 00:00:00
abstract：:A 24-year-old woman with acute optic neuritis is presented. Appropriate management and treatment of this case using the Optic Neuritis Treatment Trial guidelines and an evaluation of the cost involved is discussed. ...
journal_title：Survey of ophthalmology
pub_type： 杂志文章
doi：10.1016/s0039-6257(97)00117-3
更新日期：1998-01-01 00:00:00
