-
Journal of the American Veterinary... Dec 2012To compare the corneal anesthetic effects and duration of action of 2 ophthalmic anesthetic agents in horses. (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To compare the corneal anesthetic effects and duration of action of 2 ophthalmic anesthetic agents in horses.
DESIGN
Prospective, randomized masked crossover study.
ANIMALS
8 clinically normal adult horses.
PROCEDURES
Corneal sensitivity was determined by measuring each eye's corneal touch threshold (CTT) with a Cochet-Bonnet esthesiometer. Each eye's baseline CTT was recorded prior to anesthetic instillation at 0 minutes and every 10 minutes thereafter for 60 minutes. Each eye was randomly assigned to receive 2 of 4 treatments: 0.5% aqueous proparacaine ophthalmic solution (aqueous proparacaine; 8 eyes); 0.5% aqueous tetracaine ophthalmic solution (aqueous tetracaine; 8 eyes); 0.5% viscous tetracaine ophthalmic solution (viscous tetracaine; 8 eyes); and saline (0.9% NaCl) eyewash solution (8 eyes) as a negative control. There was a 48-hour washout period. Every horse received all treatments.
RESULTS
Median baseline CTT of eyes was 4.5 cm (range, 0.5 to 6 cm). Median CTT for saline solution-treated eyes never differed significantly from baseline. The maximum anesthetic effect with the other 3 treatments occurred at 10 minutes. Median CTT of eyes at 10 minutes was 0.5 cm (range, 0 to 2.5 cm) with aqueous proparacaine treatment, 0.25 cm (range, 0 to 2.0 cm) with aqueous tetracaine treatment, and 0 cm (range, 0 to 0.5 cm) with viscous tetracaine treatment. Maximum anesthetic duration was 20 minutes with aqueous proparacaine and aqueous tetracaine treatments and 30 minutes with viscous tetracaine treatments.
CONCLUSIONS AND CLINICAL RELEVANCE
Treatment of eyes with viscous tetracaine resulted in the greatest decrease in CTT and the longest duration of action, compared with treatment with aqueous proparacaine or aqueous tetracaine.
Topics: Administration, Topical; Anesthesia, Local; Anesthetics, Local; Animals; Cornea; Cross-Over Studies; Horse Diseases; Horses; Ophthalmic Solutions; Propoxycaine; Tetracaine
PubMed: 23216041
DOI: 10.2460/javma.241.12.1645 -
Pediatrics and Neonatology Dec 2015To report the success rates of office probing for congenital nasolacrimal duct obstruction (NLDO) among children of different age groups in Taiwan.
BACKGROUND
To report the success rates of office probing for congenital nasolacrimal duct obstruction (NLDO) among children of different age groups in Taiwan.
METHODS
In this single-center, retrospective study, 564 eyes of 477 patients under the age of 5 years diagnosed with congenital NLDO were treated in a stepwise manner between 2001 and 2013. For infants aged < 6 months, treatment with massage and observation was suggested, followed by deferred probing under topical anesthesia if symptoms persisted. However, in cases of severe infection, immediate probing was suggested. In children aged > 6 months, office probing was usually highly recommended. Those with probing failures received either a second probing or silicone intubation. Treatment success was defined as anatomic patency by immediate irrigation after probing and absence of epiphora or mucous discharge at the follow-up visit.
RESULTS
Primary probing was successful in 457 of 564 eyes (success rate: 81%). The success rate of primary probing was negatively correlated with increasing age: 90.1% (163/181), 79.6% (164/206), 76.8% (73/95), 73.5% (36/49), 75% (18/24), and 33% (3/9) for the age groups of 0 to <6 months, 6 to <12 months, 12 to <18 months, 18 to <24 months, 24 to <36 months, and 36-60 months, respectively (p < 0.001, Fisher's exact test). The second probing was successful in 52 of 81 eyes. In total, probing was successful in 509 of 564 eyes (success rate: 90.2%).
CONCLUSION
Office probing is safe and effective for treating congenital NLDO. The success rate of primary probing decreases significantly with age.
Topics: Age Factors; Ambulatory Surgical Procedures; Anesthetics, Local; Child, Preschool; Dacryocystorhinostomy; Female; Humans; Infant; Infant, Newborn; Lacrimal Duct Obstruction; Male; Nasolacrimal Duct; Propoxycaine; Retrospective Studies; Taiwan
PubMed: 26026949
DOI: 10.1016/j.pedneo.2015.04.001 -
American Journal of Veterinary Research Dec 2008To measure duration of corneal anesthesia and time and degree of maximal anesthetic effect of 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in...
OBJECTIVE
To measure duration of corneal anesthesia and time and degree of maximal anesthetic effect of 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in horses.
ANIMALS
10 clinically normal adult horses.
PROCEDURES
Baseline corneal touch threshold (CTT) was measured in millimeters for 1 randomly selected eye of each horse by use of the aesthesiometer by applying the filament to the cornea at maximum length (60 mm) and decreasing in 5-mm increments until a consistent blink response was elicited. Following baseline CTT measurement, 0.2 mL of 0.5% proparacaine hydrochloride was instilled in the selected eye. The CTT was measured within 1 minute following proparacaine administration and every 5 minutes thereafter for 60 minutes. A mixed-model ANOVA with tested eye varying between subjects and measurement time varying within subject was used to test for main effects and any interaction between these factors. A contrast between means of baseline and each subsequent CTT identified the duration of corneal anesthesia as the time at which there was no difference from baseline. Maximal anesthetic effect occurred at the time with the lowest mean CTT.
RESULTS
Duration of corneal anesthesia achieved by use of proparacaine was 25 minutes, and maximal anesthetic effect occurred within 5 minutes, although CTT never went to 0 in any horse at any time.
CONCLUSIONS AND CLINICAL RELEVANCE
Duration of corneal anesthesia in horses was shorter than in dogs, and degree of maximal effect was less than in cats and dogs, most likely because of increased sensitivity of the equine cornea, compared with corneal sensitivity in those species.
Topics: Administration, Topical; Anesthesia, Local; Anesthetics, Local; Animals; Cornea; Horses; Ophthalmic Solutions; Propoxycaine
PubMed: 19046014
DOI: 10.2460/ajvr.69.12.1655 -
American Journal of Veterinary Research Mar 2013To compare efficacy and duration of effect on corneal sensitivity of 0.5% proparacaine hydrochloride, 0.5% bupivacaine hydrochloride, 2% lidocaine hydrochloride, and 2%... (Comparative Study)
Comparative Study
OBJECTIVE
To compare efficacy and duration of effect on corneal sensitivity of 0.5% proparacaine hydrochloride, 0.5% bupivacaine hydrochloride, 2% lidocaine hydrochloride, and 2% mepivacaine hydrochloride solutions following ocular administration in clinically normal horses.
ANIMALS
68 clinically normal horses.
PROCEDURES
60 horses were assigned to receive 1 anesthetic agent in 1 eye. For each of another 8 horses, 1 eye was treated with each of the anesthetic agents in random order with a 1-week washout period between treatments. Corneal sensitivity was assessed via corneal touch threshold (CTT) measurements obtained with a Cochet-Bonnet aesthesiometer before and at 1 minute, at 5-minute intervals from 5 to 60 minutes, and at 10-minute intervals from 60 to 90 minutes after application of 0.2 mL of anesthetic agent. General linear mixed models were fitted to the CTT data from each of the 2 experimental groups to assess the effects of the anesthetic agents over time, accounting for repeated observations within individual horses.
RESULTS
Corneal sensitivity decreased immediately following topical application of each anesthetic agent; effects persisted for 35 minutes for proparacaine and mepivacaine treatments, 45 minutes for lidocaine treatment, and 60 minutes for bupivacaine treatment. Maximal CTT reduction was achieved following application of bupivacaine or proparacaine solution, whereas mepivacaine solution was least effective.
CONCLUSIONS AND CLINICAL RELEVANCE
Ocular application of each evaluated anesthetic agent reduced corneal sensitivity in horses; although 0.5% proparacaine or 2% lidocaine solution appeared to induce adequate short-duration corneal anesthesia, use of 0.5% bupivacaine solution may be more appropriate for procedures requiring longer periods of corneal anesthesia.
Topics: Administration, Ophthalmic; Anesthesia, Local; Animals; Bupivacaine; Cornea; Female; Horses; Lidocaine; Linear Models; Male; Mepivacaine; Propoxycaine; Random Allocation
PubMed: 23438124
DOI: 10.2460/ajvr.74.3.459 -
American Journal of Veterinary Research Jan 2005To determine the duration of effect and the effect of multiple doses of topical ophthalmic application of 0.5% proparacaine hydrochloride on corneal sensitivity in... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
OBJECTIVE
To determine the duration of effect and the effect of multiple doses of topical ophthalmic application of 0.5% proparacaine hydrochloride on corneal sensitivity in clinically normal dogs.
ANIMALS
8 clinically normal dogs.
PROCEDURE
Dogs were randomly allocated to treatment order in a 2 x 2 (period X treatment) crossover study. Treatments consisted of topical application of ophthalmic 0.5% proparacaine (1 drop or 2 drops at a 1-minute interval); treatments were applied to both eyes. A Cochet-Bonnet aesthesiometer was used to determine corneal touch threshold (CTT) before corneal application, 1 and 5 minutes after corneal application, and at 5-minute intervals thereafter for 90 minutes.
RESULTS
The CTT value before treatment differed significantly from CTT values after treatment until 45 minutes after application in the 1-drop group and until 55 minutes after application in the 2-drop group. As determined by use of the Cochet-Bonnet aesthesiometer, a significantly greater anesthetic effect was detected for the 2-drop treatment, compared with the effect for the 1-drop treatment, at 30, 35, 40, 45, 50, and 55 minutes after application. Maximal anesthetic effect lasted for 15 minutes for the 1-drop treatment and 25 minutes for the 2-drop treatment.
CONCLUSIONS AND CLINICAL RELEVANCE
Duration of corneal anesthetic effect induced by topical ophthalmic application of 0.5% proparacaine in dogs of this study is considerably longer than that reported elsewhere. Serial application of doses of 0.5% proparacaine increases the duration and magnitude of corneal anesthetic effects.
Topics: Administration, Topical; Anesthetics, Local; Animals; Cornea; Dogs; Ophthalmic Solutions; Propoxycaine; Time Factors
PubMed: 15691039
DOI: 10.2460/ajvr.2005.66.77 -
Journal of the Formosan Medical... Dec 2009Anesthetic toxic keratitis is rare and presents as a ring keratitis, which is often misdiagnosed as Acanthamoeba keratitis. Here, we report an unusual case of toxic...
Anesthetic toxic keratitis is rare and presents as a ring keratitis, which is often misdiagnosed as Acanthamoeba keratitis. Here, we report an unusual case of toxic keratitis caused by topical abuse of a dilute anesthetic. A 26-year-old woman presented with bilateral corneal edema, ring infiltrates, pigmented keratic precipitate, Descemets membrane folding, and strong anterior chamber reactions 2 weeks after laser subepithelial keratomileusis surgery. Tracing back her medical history, topical dilute 0.1% proparacaine was prescribed and frequently used for 1 month. Toxic keratitis was suspected. After discontinuation of the topical anesthetic and initiation of treatment with topical 20% autologous serum, complete corneal epithelialization was achieved within 1 week. Corneal infiltrates and anterior chamber reaction gradually subsided. Vision improved from finger counting to 20/20 in the right eye and 20/25 in the left eye, but confocal microscopy showed decreased corneal endothelial cells. Topical abuse of a dilute topical anesthetic can cause severe toxic keratitis and endothelial cell loss. The physician must be aware of the signs of topical anesthetic abuse and should not prescribe even a dilute anesthetic for long-term use. Autologous serum can help in the recovery of toxic keratitis.
Topics: Adult; Anesthetics, Local; Endothelial Cells; Female; Humans; Keratitis; Propoxycaine; Refractive Surgical Procedures
PubMed: 20040463
DOI: 10.1016/S0929-6646(10)60011-3 -
The British Journal of Ophthalmology Nov 1998To evaluate the claim that topical proxymetacaine produces little or no discomfort on instillation by comparing it against topical amethocaine. (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
AIMS
To evaluate the claim that topical proxymetacaine produces little or no discomfort on instillation by comparing it against topical amethocaine.
METHODS
This randomised, masked, double blind, prospective study involved 53 consecutive patients. Each patient received one drop of amethocaine 0.5% in one eye and one drop of proxymetacaine 0.5% in the other. The duration of the stinging sensation and degree of discomfort (using descriptive and a linear analogue method) for each topical anaesthetic was assessed.
RESULTS
The mean duration of stinging was 3.2 seconds for proxymetacaine and 22.1 seconds for amethocaine the difference being statistical significant (p < 0.001). The mean descriptive discomfort score was 2.6 for proxymetacaine and 14.2 for amethocaine (p = 0.01). The mean linear analogue score was 5.8 for proxymetacaine and 35.6 for amethocaine (p < 0.001). Proxymetacaine had a successful tonometry rate of 93% and amethocaine 98%.
CONCLUSION
This clinical study confirms that proxymetacaine is more comfortable on instillation than amethocaine. Minimising unnecessary patient discomfort is not only ideal, but encourages cooperation in apprehensive patients especially in children.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anesthetics, Local; Double-Blind Method; Female; Humans; Male; Middle Aged; Ophthalmic Solutions; Pain; Pain Measurement; Patient Satisfaction; Propoxycaine; Prospective Studies; Tetracaine
PubMed: 9924334
DOI: 10.1136/bjo.82.11.1285 -
Eye (London, England) Aug 2015
Randomized Controlled Trial
Topics: Adult; Anesthetics, Local; Double-Blind Method; Eye Pain; Female; Humans; Male; Middle Aged; Ophthalmic Solutions; Pain Measurement; Propoxycaine; Prospective Studies; Refrigeration; Young Adult
PubMed: 25907208
DOI: 10.1038/eye.2015.59 -
The British Journal of Ophthalmology Nov 1993A novel ophthalmic drug delivery system (NODS) has been developed to give precise and controlled delivery of a drug to the eye. The drug is incorporated into a polyvinyl... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
A comparison of the efficacy and duration of action of topically applied proxymetacaine using a novel ophthalmic delivery system versus eye drops in healthy young volunteers.
A novel ophthalmic drug delivery system (NODS) has been developed to give precise and controlled delivery of a drug to the eye. The drug is incorporated into a polyvinyl alcohol flag attached to a carrier. When applied to the eye the flag detaches and gradually dissolves, releasing the drug. We investigated corneal anaesthesia produced by different concentrations of proxymetacaine NODS, and conventional eye drops. Subjects consisted of 28 normal males (mean age 25.3 (SD 3.9) years). Corneal touch sensitivity was measured with a biomicroscope mounted Cochet-Bonnet aesthesiometer. Each subject attended for two visits separated by 7 days. On each visit each eye randomly received one of four proxymetacaine preparations: 44 micrograms, 74 micrograms, 124 micrograms NODS, or 35 microliters of 0.5% proxymetacaine drops (175 micrograms). Corneal touch sensitivity was measured before, and at 1, 2, 5, 10, 15, 20, 30, 45, and 60 minutes following instillation. Complete anesthesia was achieved in the majority of subjects within 1 minute of instillation. The lowest NODS dose (44 micrograms) produced longer lasting anaesthesia than the 35 microliters drop (175 micrograms) (p < 0.05). Higher NODS doses produced a correspondingly greater increase in the duration of anaesthesia. The greater bioavailability achieved by this vehicle allows much lower drug concentrations to be used, reducing the likelihood of systemic adverse reactions.
Topics: Adult; Anesthetics, Local; Cornea; Dose-Response Relationship, Drug; Humans; Male; Ophthalmic Solutions; Propoxycaine; Time Factors; Touch
PubMed: 8280685
DOI: 10.1136/bjo.77.11.713 -
Molecular Vision Nov 2003In a previous toxicological study, cultured bovine lenses exposed to three topical anesthetics displayed distinct patterns of optical damage and recovery. This work... (Comparative Study)
Comparative Study
PURPOSE
In a previous toxicological study, cultured bovine lenses exposed to three topical anesthetics displayed distinct patterns of optical damage and recovery. This work investigated the epithelial activity of the metabolic enzymes hexokinase (HK) and glucose-6-phosphate dehydrogenase (G6PD) in lenses recovering from anesthetic-induced damage.
METHODS
Cultured bovine lenses were exposed to the anesthetics Alcaine, Fluress and Fluoracaine for 2 h. An automated laser scanner was used to determine the focal length variability (FLV) of the lenses at time-points up to 24 h following their return to fresh culture medium. The epithelial enzyme activities for HK and G6PD were then assayed at the 24 h time-point.
RESULTS
Lenses exposed to Alcaine displayed an abrupt increase in FLV, while Fluoracaine treated lenses exhibited optical damage at a slower rate. The FLV in these two groups recovered to near-control levels after 24 h. Fluress treated lenses did not differ in FLV from controls at any time. The activities of both HK and G6PD were significantly reduced in epithelial samples from each of the three anesthetic treatment groups, relative to controls.
CONCLUSIONS
These results show that lens optical quality can recover despite a severe reduction in epithelial HK and G6PD activity, indicating that the optical function of the lens may not be directly related to epithelial metabolic activity. The ScanTox In Vitro Assay System provides an objective measure of lens optical quality, enabling a direct comparison of optical damage and recovery to lens biochemical changes.
Topics: Anesthetics, Local; Animals; Cattle; Chlorobutanol; Culture Media; Drug Combinations; Edetic Acid; Epithelial Cells; Fluorescein; Fluoresceins; Glucosephosphate Dehydrogenase; Hexokinase; Lens, Crystalline; Organ Culture Techniques; Povidone; Preservatives, Pharmaceutical; Procaine; Propoxycaine
PubMed: 14627957
DOI: No ID Found