Björn Lundberg

Intracameral mydriatics in phacoemulsification cataract surgery.

Purpose: To evaluate intracameral injection of mydriatics in phacoemulsification cataract surgery and compare the results with those of conventional topical mydriatics. Setting: Department of Clinical Science/Ophthalmology, Umeå University Hospital, Umeå, Sweden. Methods: This prospective randomized double‐blind study included 60 patients who were given topical (topical group) or intracameral (intracameral group) mydriatics. The topical mydriatics comprised 3 drops of cyclopentolate 1% and phenylephrine 10% given 15 minutes apart and 150 &mgr;L intracameral lidocaine hydrochloride 1% (Xylocaine®) and the intracameral mydriatics, placebo eyedrops and 150 &mgr;L intracameral cyclopentolate 0.1%, phenylephrine 1.5%, and Xylocaine 1%. The pupil size was recorded preoperatively, throughout surgery, and 1 day and 1 month postoperatively. Preoperative and postoperative corneal endothelial morphology, corneal thickness, intraocular pressure, visual acuity, aqueous cells and flare, phacoemulsification energy, duration of surgery, pulse, blood pressure, and intraoperative sensation of pain and glare were also recorded. Results: With intracameral mydriatics, mydriasis reached 95% ± 3% (SD) of its final value within 20 seconds. In the intracameral group, the pupils were smaller than in the topical group (mean 6.7 ± 1.0 mm versus 7.7 ± 1.0 mm, P<.001) but did not contract intraoperatively. The pupils in the topical group tended to contract, and the difference between groups was significant (P = .0020). The intracameral group reported less glare during the procedure (P<.001). There was no difference in endothelial cell loss, inflammatory reaction, postoperative corneal swelling, or surgical performance between the groups. Conclusions: Intracameral mydriatics were a rapid, effective, and safe alternative to topical mydriatics in phacoemulsification. Their use can simplify preoperative routines and in certain high‐risk groups, may reduce the risk for cardiovascular side effects.

transient corneal edema after phacoemulsification: comparison of 3 viscoelastic regimens ☆

Purpose: To evaluate the effect of different viscoelastic substances on the grade and time course of postoperative corneal edema. Setting: Department of Clinical Sciences/Ophthalmology, Umeå University Hospital, Umeå, Sweden. Methods: This study comprised 62 patients with otherwise healthy eyes who had routine phacoemulsification and intraocular lens (IOL) implantation. Patients were divided into 3 groups. Group 1 was given Healon GV® (sodium hyaluronate 1.4%) at phacoemulsification and IOL implantation. Group 2 was given Viscoat® (sodium hyaluronate 3.0%–chondroitin sulfate 4.0%) at phacoemulsification and Healon GV at IOL implantation. Group 3 was given Viscoat at phacoemulsification and Provisc® (sodium hyaluronate 1.0%) at lens implantation. The central corneal thickness was measured with ultrasonic pachymetry before surgery and 5 and 24 hours, 1 week, and 1 month after surgery. Results: The mean increase in corneal thickness was significantly greater in Group 1 than in the other 2 groups 5 and 24 hours and 1 week after surgery. Conclusions: The transient postoperative increase in central corneal thickness was greater in patients receiving Healon GV during phacoemulsification than in patients receiving Viscoat. The use of Provisc or Healon GV for IOL implantation did not affect the postoperative corneal thickness when Viscoat was used for phacoemulsification. The time course of the edema may be explained by a difference between the 2 agents in endothelial protection from ultrasonic, mechanical, or irrigation trauma.

Separate and additive mydriatic effects of lidocaine hydrochloride, phenylephrine, and cyclopentolate after intracameral injection.

PURPOSE: To assess the separate mydriatic effect of lidocaine hydrochloride (Xylocaine), cyclopentolate, and phenylephrine after intracameral injection and evaluate whether intracameral Xylocaine and phenylephrine without cyclopentolate provide sufficient pupil dilation for cataract surgery. SETTING: Department of Clinical Science/Ophthalmology, Umeå University Hospital, Umeå, Sweden. METHODS: This prospective randomized double‐masked study included 56 patients with age‐related cataract scheduled for unilateral phacoemulsification. In 16 patients, Xylocaine 1%, phenylephrine 1.5%, and cyclopentolate 0.1% were injected one after the other. Phenylephrine and cyclopentolate were randomized to switch in order, creating 2 study groups. An additional 40 patients were randomized to receive intracameral Xylocaine 1%, phenylephrine 1.5%, and cyclopentolate 0.1% or intracameral Xylocaine 1% and phenylephrine 1.5% only. RESULTS: Xylocaine alone caused significant pupil dilation (mean 4.9 ± 0.6 mm). In the group in which cyclopentolate was injected next, the pupil size increased 1.3 ± 0.6 mm (P<.001). When phenylephrine was added, the pupil increased an additional 0.7 ± 0.4 mm (P = .003). In the second group, in which phenylephrine was the second injection, the pupil size increased 2.1 ± 0.5 mm (P<.001). When cyclopentolate was added, no significant change in size occurred. No statistically significant differences in pupil size were observed between the 40 patients who were given intracameral mydriatics with or without cyclopentolate. CONCLUSIONS: Xylocaine plus phenylephrine injected intracamerally gave adequate intraoperative pupil dilation in routine phacoemulsification surgery. Cyclopentolate administrated intracamerally had no immediate additive mydriatic effect to intracameral Xylocaine combined with phenylephrine.

Optical coherence tomography evaluation of macular edema after phacoemulsification surgery with intracameral mydriatics

PURPOSE: To quantify the macular edema induced by intracameral mydriatics in phacoemulsification surgery. SETTING: University hospital eye clinic, Umeå, Sweden. METHODS: In a randomized study of 22 patients, 11 patients were given 150 μL of a mixture of phenylephrine 1.5% and lidocaine 1% intracamerally for mydriasis and anesthesia. In a control group (n = 11), conventional topical mydriatics and intracameral lidocaine were given. Multiple preoperative, intraoperative, and postoperative variables were recorded. RESULTS: There were no differences in macular edema between the 2 treatments. A correlation was seen between macular edema and impaired visual acuity 1 week postoperatively. On the first postoperative day, a similar correlation was seen between corneal edema and the degree of visual improvement. CONCLUSIONS: Intracameral lidocaine and phenylephrine for mydriasis and anesthesia did not induce more significant macular edema than the standard regimen of topical mydriatics plus intracameral lidocaine. Macular edema limited visual improvement 1 week after phacoemulsification, while corneal edema appeared to have a larger effect immediately after surgery.

Intracameral mydriatics in phacoemulsification cataract surgery – a 6-year follow-up

Purpose:  To evaluate the long‐term safety of intracameral mydriatics (ICM) in phacoemulsification cataract surgery compared with conventional topical mydriatics (TM).

Mydriatic response to different concentrations of intracameral phenylephrine in humans

PURPOSE: To assess the mydriatic response to concentrations of intracamerally injected phenylephrine from 0.15 mg/mL to 30.00 mg/mL (0.015% to 3.000%) in human eyes. SETTING: Department of Clinical Science/Ophthalmology, Umeå University Hospital, Umeå, Sweden. DESIGN: Comparative case series. METHODS: This prospective randomized double‐masked study comprised patients scheduled for phacoemulsification cataract surgery. At the beginning of the procedure, patients received an intracameral injection of 0.15 mL of phenylephrine 0.15, 0.5, 1.5, 5.0, 15.0, or 30.0 mg/mL. To assess the mydriatic response, the pupil size was registered over 60 seconds using digital video recording. Then, the surgery was performed in the standard manner. RESULTS: The study evaluated 42 patients. The mydriatic response was almost identical at the 4 lower phenylephrine concentrations (0.15 to 5.00 mg/mL; 0.015% to 0.500%), with final pupil sizes of approximately 4.3 mm. The 2 higher concentrations gave significantly larger pupils as follows: mean 5.80 mm ± 0.79 (SD) for 15.0 mg/mL (1.5%) and 6.65 mm ± 0.57 for 30.0 mg/mL (3.0%). CONCLUSIONS: Results show that phenylephrine injected intracamerally does not have a linear mydriatic dose‐response relationship in humans. At very high concentrations, phenylephrine may bind to and stimulate receptors other than the α1‐receptor, explaining this phenomenon. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned.

The Mydriatic Effect of Intracameral Epinine Hydrochloride

PURPOSE To compare the mydriatic effect and the short-term corneal endothelial safety of intracamerally injected N-methyl-3,4-dihydroxyphenylamine (epinine) to phenylephrine in a porcine eye model. METHODS One hundred twelve eyes from newly slaughtered pigs were used in this study. After pretreatment with 20 mg intracameral acetylcholine to give miosis, 0.15 mL epinine or phenylephrine 0.3%, 1.5%, or 3.0% was given as an intracameral injection. The pupils were filmed during 90 seconds with a video camera connected to an operation microscope, and the mean pupil diameters were measured from the video recordings. In 37 additional eyes, 0.15 mL vehicle, 1.5% epinine, or 1.5% phenylephrine was injected intracamerally, and the eyes were kept on ice overnight. Corneal endothelial morphology was assessed before and after the treatment. Ten eyes were given no injection and served as controls. RESULTS; Epinine had a significantly larger mydriatic effect than phenylephrine at equal concentrations. Endothelial cell loss was equal with both substances and did not exceed that of the vehicle. CONCLUSIONS Epinine was a more potent mydriatic than phenylephrine in this porcine eye model. The porcine eye model appears suitable as a first efficacy screening of substances for intraocular use. Epinine is a promising candidate substance for intraoperative (e.g., cataract surgery) intracameral use in humans.

Preoperative topical cyclopentolate can be omitted when using intracameral lidocaine in phacoemulsification surgery

Purpose:  To evaluate the mydriatic effect of topical cyclopentolate 1% when combined with topical phenylephrine 10% and intracameral lidocaine 1% in phacoemulsification cataract surgery.

Intracameral acetylcholine effectively contracts pupils after dilatation with intracameral mydriatics

Purpose:  To determine whether intracameral acetylcholine can contract pupils dilated with intracameral mydriatics in phacoemulsification cataract surgery.

Stimulation of adrenergic β-receptors enhances mydriasis in a porcine eye model

Purpose:  To compare the mydriatic effect of intracamerally injected isoprenaline plus phenylephrine to phenylephrine alone and to epinephrine in a porcine eye model, aiming to eventually find the best combination of adrenergic substances for surgical mydriasis in humans.