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1.
PURPOSE: Rigid gas-permeable (RGP) lens adherence after overnight lens wear is clearly a patient-dependent phenomenon. However, no previous study has attempted to determine whether specific ocular characteristics are associated with an increased frequency of lens adherence. METHOD: In this study, clinically applicable tests were used to measure a range of ocular characteristics, including central and peripheral corneal curvature, tear film status, eyelid characteristics, central corneal thickness, and ocular rigidity in a group of 22 young adult subjects for whom reliable estimates for frequency of overnight RGP lens adherence had been obtained from earlier studies. RESULTS: Linear discriminant analysis revealed that a higher frequency of lens adherence was associated with lower ocular rigidity, thinner central corneas, greater eyelid tension, and lower amounts of corneal astigmatism. CONCLUSIONS: These findings suggest a clinical approach for identifying patients who may develop clinically significant lens adherence during RGP extended wear, and also provide support for the "thin film adherence" theory of RGP lens adherence.  相似文献   

2.
Eyelid problems range from benign, self-resolving processes to malignant, possibly metastatic, tumors. Inflammation, infection, benign and malignant tumors, and structural problems such as ectropion, entropion and blepharoptosis may occur. Fortunately, most eyelid disorders are not vision-threatening or life-threatening; however, many cause irritative symptoms such as burning, foreign-body sensation or pain. Blepharitis, or eyelid inflammation, one of the most common problems, is characterized by erythematous eyelids with accumulation of debris along the eyelid margin. Malignant eyelid tumors may be associated with lash loss and erosion of normal eyelid structures. Recognition and diagnosis of these problems are crucial to their proper management. Warm compresses and antibiotics suffice for many conditions, while excision, cryotherapy or laser treatment are required for some.  相似文献   

3.
BACKGROUND: Accurate ultrasonography data on axial ocular dimensions in infants and toddlers are essential for understanding ocular development. Conventional methods using corneal contact with topical anesthesia but without sedation are not feasible for most of these patients. We evaluate an alternative method which places the probe on the closed eyelid. METHODS: We compared A-scan ultrasound biometry measurements taken with the probe directly on the cornea with those with the probe on the closed eyelid on the right eye of 35 young adult subjects. RESULTS: There was no significant difference between methods for mean anterior chamber depth (corneal = 3.83 mm, lid = 3.87 mm, p = 0.13, paired t-test). The mean lens thickness (corneal = 3.63 mm, lid = 3.75 mm, p = 0.0001, paired t-test) and mean vitreous chamber depth (corneal = 17.50 mm, lid = 17.68 mm, p = 0.0440, paired t-test) were significantly different. CONCLUSION: Ultrasonography through the closed eyelid appears to be a viable method with acceptable validity compared with corneal ultrasound. Poorer agreement for lens thickness and vitreous chamber depth may be undesirable, but these data should be useful for planning future studies of infants and toddlers.  相似文献   

4.
Corneal afferent projections to the trigeminal brainstem nuclear complex (TBNC) and associated structures, as determined by transganglionic transport of various tracers, were found to be predominantly concentrated in two distinct patches in the dorsolateral medulla at periobex levels. One was in the external cuneate nucleus, and the other was in the ventralmost part of the ophthalmic division of the TBNC. The projections of putative second-order neurons in these regions, as determined by injections of wheat germ agglutinin conjugated to horseradish peroxidase into the dorsolateral medulla, were found to include the dorsal trigeminal motor nucleus (Vd), which innervates the M. depressor palpebrae inferioris. Electrical stimulation of Vd, which elicited lower eyelid movements, was then used to guide injections of tracer into Vd, which retrogradely labeled clusters of neurons in the corneal afferent recipient regions of the dorsolateral medulla. The lower eyelid of pigeons, unlike the nictitating membrane and upper lid, does not appear to be appreciably involved in either reflex blinking in response to relatively mild stimulation of the cornea (e.g., air puff), or in eye closure during the saccade-like head movements associated with walking, or in eye closure during pecking; but in response to a stimulus that makes corneal contact, an upward movement of the lower lid follows descent of the nictitating membrane and upper lid as part of a defensive eye-closing mechanism. The anatomical results thus appear to define a dedicated disynaptic trigeminal sensorimotor circuit for the control of lower eyelid motility in response to mechanical or noxious stimuli of the cornea. Injections of tracers into the lower and upper eyelids labeled palpebral sensory afferents that terminated predominantly in maxillary and ophthalmic portions, respectively, of the dorsal horn of upper cervical spinal segments. These terminal fields were therefore largely separate from those of corneal afferents. There were no specific corneal afferent projections upon accessory abducens motoneurons that innervate the two muscles controlling the nictitating membrane.  相似文献   

5.
This article presents three cases of decreased vision due to acquired hyperopia, which were caused by a chalazion of the upper eyelid. Through manifest refraction and computerized corneal topographic analysis, acquired hyperopia associated with central corneal flattening was revealed. These findings were responsible for the blurred vision that was reversed by chalazion resolution or removal. Although not usually considered a risk factor for refractive disorders other than astigmatism, chalazia of the upper eyelid can present as a decrease in vision associated with reversible central corneal flattening and acquired hyperopia.  相似文献   

6.
Lower eyelid malposition is the most common long-term complication following transcutaneous lower eyelid blepharoplasty. The malposition may include rounding of the lateral canthal angle, lower eyelid retraction with inferior scleral show, or frank ectropion. The result is cosmetically unacceptable and may be associated with tearing, irritation, and other exposure keratitis symptoms. Multiple factors, including lower eyelid laxity, shortage of skin, and scarring of the middle lamella, may be responsible for this malposition. A systematic examination of the lower eyelid, as presented, helps to assess the degree to which each of these factors is responsible for the malposition. Patients with the most severe degree of lower eyelid malposition generally have middle lamella scarring. If this abnormality is not addressed, lower eyelid procedures aimed at correcting the malposition are doomed to failure. In the presence of significant middle lamella scarring, a spacer is required to provide vertical height and stiffness to support the lower eyelid following release of the cicatrix. A systematic approach aimed at addressing the underlying abnormalities was developed. In patients with significant middle lamella scarring, hard palate mucosa grafts were used as spacers in 29 eyelids (17 patients). A lateral canthotomy and transconjunctival incision allow access to the scarring in the lower eyelid retractors and septum. After careful release of all cicatrix, a hard palate mucosa graft is inserted between the lower border of the tarsal plate and the recessed conjunctiva, lower eyelid retractors, and septum. Horizontal lower eyelid laxity, when present, is corrected by performing a lateral tarsal strip. Most patients do not have a true deficiency of the anterior lamella (skin and orbicularis oculi muscle). When a moderate amount of anterior lamella deficiency is present with significant scarring of the middle lamella, the technique we describe allows correction of the lower eyelid malposition without a skin graft. After a follow-up interval of 6 to 30 months (mean 14 months), excellent results were obtained in all eyelids. Complications included corneal abrasions in two eyes before routine use of bandage cornea contact lenses at the end of surgery and a secondary bleed from the roof of the mouth in one patient. Palate mucosa closely resembles tarsus and provides excellent vertical support to the eyelid. It is stiff enough to maintain eyelid contour without causing a cosmetically unacceptable bump. Tissue can be obtained with ease. The technique, as described, addresses the underlying causes of lower eyelid malposition and gives excellent functional and cosmetic results.  相似文献   

7.
8.
BACKGROUND: Eighteen patients with chronic ocular irritation were examined over a 3-year period. All patients demonstrated papillary conjunctivitis and, occasionally, tarsal ulcers. Six also had floppy eyelid syndrome. Underlying every patient's symptoms was the overriding or imbrication of a lax upper eyelid on an often equally lax lower eyelid, allowing lower eyelid lashes to chronically rub the upper eyelid tarsal conjunctiva. METHODS: Chronic ocular irritation in five patients was managed with ocular lubricants. Two of these patients had floppy eyelid syndrome and required nightime shielding for nocturnal eyelid eversion. Thirteen patients underwent eyelid surgery to correct the overriding upper eyelid. Surgical procedures included full-thickness upper eyelid wedge resection, lateral canthal tendon plication, and lower eyelid horizontal shortening, using a tarsal strip procedure. RESULTS: Follow-up averaged 2.5 years. Symptomatology was adequately controlled in all patients. In addition to the five patients who received medical treatment for their symptoms, two with complicated ocular problems required continued ocular lubrication after surgery. Seven patients were successfully treated with eyelid shortening procedures and lateral canthal tendon plication. The remaining six patients underwent a variety of additional eyelid surgeries. All patients undergoing surgery had complete resolution of eyelid imbrication. CONCLUSIONS: Eyelid imbrication is a previously unrecognized cause of chronic ocular irritation. In this condition, eyelid laxity causes the upper eyelid to override the lower eyelid, allowing the lower eyelid to chronically rub and chafe the upper eyelid tarsal conjunctiva. In some cases, symptoms can be managed medically. More often, surgical intervention is required to correct eyelid laxity and prevent overriding of the upper eyelid.  相似文献   

9.
The discharge of antidromically identified brainstem and cerebellar nuclear neurons involved in the corneal reflex was recorded in the alert cat during corneal air puffs. Eye movements were measured with the search coil technique. Recorded sensory, motor, reticular formation and cerebellar nuclear neurons showed a wide diversity in latencies and patterns of response to air puff stimulation. This diversity suggests that each part of the circuit may contribute different properties to information processing for the corneal reflex, for sustained eyelid closure and, possibly, for the classical conditioning of the nictitating membrane response.  相似文献   

10.
BACKGROUND: Subarachnoid bupivacaine blockade has been reported to reduce thiopental and midazolam hypnotic requirements in patients. The purpose of this study was to examine if local anesthetically induced lumbar intrathecal blockade would reduce thiopental requirements for blockade of motor responses to noxious and nonnoxious stimuli in rats. METHODS: After intrathecal and external jugular catheter placement, rats were assigned randomly to two groups in a crossover design study, with each rat to receive either 10 microl of 0.75% bupivacaine or 10 microl of normal saline intrathecally. The doses of intravenously administered thiopental required to ablate the eyelid reflex, to block the withdrawal reflex of a front limb digit, and to block the corneal reflex were compared. In two separate groups of animals, hemodynamic parameters and concentrations of thiopental in the brain were compared between intrathecally administered bupivacaine and saline. RESULTS: The thiopental dose required to block the described responses was decreased with intrathecally administered bupivacaine versus intrathecally administered saline from (mean +/- SD) 40 +/- 5 to 24 +/- 4 mg/kg (P < 0.001) for the eyelid reflex, from 51 +/- 6 to 29 +/- 6 mg/kg (P < 0.005) for front limb withdrawal, and from 67 +/- 8 to 46 +/- 8 mg/kg (P < 0.01) for the corneal reflex. The concentration of thiopental in the brain at the time of corneal reflex blockade for the group given bupivacaine was significantly lower than in the group given saline (24.1 vs. 35.8 microg/g, P = 0.02). CONCLUSION: This study demonstrates that lumbar intrathecally administered local anesthetic blockade decreases anesthetic requirements for thiopental for a spectrum of end points tested. This effect is due neither to altered pharmacokinetics nor to a direct action of the local anesthetic on the brain; rather, it is most likely due to decreased afferent input.  相似文献   

11.
12.
MJ Perry  J Langtry  IC Martin 《Canadian Metallurgical Quarterly》1997,23(5):395-7; discussion 397-8
BACKGROUND: Full-thickness lower eyelid reconstruction requires functional as well as aesthetic considerations to be successful in the long term. The three elements necessary for a stable result are skin, mucosa, and a semirigid "skeleton" to provide the support that prevents the development of ectropion. A number of techniques combining these elements are described in the literature, with reconstruction in one or more stages. OBJECTIVE: We report a simple method of reconstruction of a full-thickness lower eyelid defect, in which palatal mucoperiosteum provided both the mucosal and the "skeletal" components following tumor excision. METHODS: Literature review and report of illustrated case. RESULTS: A cosmetically acceptable result with no functional deficit or donor site morbidity. CONCLUSION: Palatal mucoperiosteum provides an abundant supply of tissue that may be used successfully in the reconstruction of the lower eyelid. It functions both as a mucosal lining in addition to a semirigid supporting framework.  相似文献   

13.
A case with M?bius' facial diplegia is described; the syndrome is characterized by bilateral congenital paralysis of the mimic muscles often associated with paralysis of the abductors of both eyes, convergent strabismus, palsy of sublingual and trigeminal nerve motor branch. This first observation of the syndrome in Russia is uncommon due to a congenital lower lid entropion which is considered untypical of this rare condition. Still, the authors do not rule out a pathogenetic relationship between entropion and other manifestations of the syndrome.  相似文献   

14.
Trichiasis is a common and potentially sight threatening complication of ocular cicatricial pemphigoid and is usually secondary to cicatricial entropion. This study aimed to assess the success and complications of eyelid cryotherapy for trichiasis in a group of patients with long term follow up. The case records of all patients with ocular cicatricial pemphigoid that attended the external disease clinic at Moorfields Eye Hospital from 1980 to 1992 were reviewed. Each eyelid was divided into three horizontal zones. Cryotherapy was delivered with an Amoilette cryoprobe for approximately 30 seconds. Failure of the cryotherapy was defined as a regrowth of the eyelashes within the treated zone that either required epilation for symptom control or caused keratopathy. Ninety two lid zones were treated, involving 25 lids of 12 patients. The cumulative chance of success decreased rapidly to 40% over the first year. Thereafter, the chance of success declined slowly to 34% at 4 years. Complications included lid notching (n = 2), tarsal atrophy (n = 1), altered lid contour (n = 1), and temporarily raised intraocular pressure (n = 1). All patients had quiescent disease at the time of the cryotherapy and no patients showed increased conjunctival disease activity after treatment. Six patients were taking systemic immunosuppression medication. When ocular cicatricial pemphigoid is quiescent, lid cryotherapy has an acceptable complication rate. The major reason for recurrence of the trichiasis was attributed to inadequate follicle freezing.  相似文献   

15.
PURPOSE: To report a patient with bilateral upper and lower eyelid margin nodules that proved to be adult colloid milium. METHODS: After clinical study, biopsy specimens were obtained and analyzed histologically and ultrastructurally. RESULTS: Adult colloid milium can be diagnosed by clinicopathologic correlation. CONCLUSION: Adult colloid milium should be included in the differential diagnosis of eyelid margin nodules.  相似文献   

16.
BACKGROUND AND OBJECTIVES: Medial canthoplasty surgically fuses the upper and lower lids medial to the puncta. The authors modified the procedure by inserting a temporary lacrimal stent in order to avoid kinking and scar contracture of the canaliculi. PATIENTS AND METHODS: A medial canthoplasty successfully corrected lower eyelid laxity in 14 patients with the following conditions: (1) exposure and/or neurotrophic keratitis with medial ectropion and/or retraction of the lower eyelid (11 patients), and (2) inability to retain a prosthesis because of lower eyelid ectropion and contracture of the inferior conjunctival fornix (3 anophthalmic patients). RESULTS: All patients had a satisfactory cosmetic result despite minimal vertical and horizontal narrowing of the palpebral fissure. Complications included partial wound dehiscence and pyogenic granuloma. CONCLUSION: The modified medial canthoplasty described in this article corrects medial ectropion with minimal cosmetic deformity.  相似文献   

17.
BACKGROUND: Disposable soft contact lenses are known to be colonized by bacteria and play a key role in bacterial keratitis pathogenesis. Such lenses, commonly used after laser refractive surgery procedures in which postoperative corneal infiltrations are sometimes observed, are potentially a substrate for bacterial inoculation. This study evaluates the extent of such a contamination. METHODS: Sixty disposable lenses collected from 60 eyes of patients who underwent photorefractive keratectomy (PRK), photoastigmatic refractive keratectomy (PARK), or laser in situ keratomileusis (LASIK) for the treatment of myopia or hyperopia were collected under sterile conditions over 4 months and cultured in various media. Results were statistically analyzed and the correlation with clinical and epidemiological data was examined. RESULTS: Eleven (18.3%) of the examined lenses were contaminated with Staphylococcus epidermidis. No other bacteria or fungi were found. Contamination was significantly more common among female patients (P = .036). Correlation with the other clinical or operative parameters examined was statistically insignificant. CONCLUSIONS: Contamination was independent of the surgical procedure and females who were frequent users of eyelid cosmetics displayed higher contamination frequencies, suggesting that bacteria possibly originate from eyelid flora. The isolation of Staphylococcus epidermidis requires close postoperative surveillance, since it is a known cause of keratitis. Prophylactic postoperative treatment with tobramycin, gentamycin, or sulphonamides could be indicated.  相似文献   

18.
19.
Abnormalities of the cornea and conjunctiva occur in association with neurological diseases, nocturnal lagophthalmos, coma, infection, and mechanical ventilation. We investigated the incidence and causes of ocular surface disorders in critically ill patients. In a retrospective study, the presence of conjunctivitis and corneal erosion was determined by reviewing the medical charts of 143 mechanically ventilated patients (intensive care unit [ICU] stay > or =7 days). In the subsequent prospective study, 15 patients who had sedatives or muscle relaxants administered continuously for more than 48 h in the ICU were investigated. Corneal erosion was examined using a slit lamp once a day. Ocular surface disorder was found in 28 of the 143 patients (20%) whose ICU stay exceeded 7 days. The incidence increased with continuous sedation (35% vs 15%). The incidence also increased with continuous neuromuscular blockade (39% vs 11%). In the prospective study, nine patients (60%) developed corneal erosion. A patient's inability to fully close his or her eyes increased the incidence (P < 0.01) of corneal erosion. Protective eyelid taping was effective in preventing and treating the corneal erosion. In conclusion, the critically ill often develop ocular surface disorders, especially when sedated and immobilized. A close relationship was observed between these conditions and the inability to close one's eyes.  相似文献   

20.
PURPOSE: To report a 20-month-old child with a rapidly growing dome-shaped red nodule on the left lower eyelid. The lesion was diagnosed clinically as an hemangioma, but microscopy disclosed an epithelioid Spitz nevus. METHOD: Case report. RESULT: Histopathologic examination of the excised lesion disclosed a Spitz nevus (benign juvenile melanoma) of a chiefly epithelioid cell type. CONCLUSIONS: The differential diagnosis of eyelid skin nodules in children should include Spitz nevus. This uncommon nevus has many cytologic features in common with nodular malignant melanoma. Histologically, it may be difficult to distinguish between nodular malignant melanoma and Spitz nevus.  相似文献   

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