Eating high fat chow enhances the locomotor-stimulating effects of cocaine in adolescent and adult female rats.

RATIONALE: Dopamine systems vary through development in a manner that can impact drugs acting on those systems. Dietary factors can also impact the effects of drugs acting on dopamine systems. OBJECTIVES: This study examined whether eating high fat chow alters locomotor effects of cocaine (1-56 mg/kg) in adolescent and adult female rats. METHODS: Cocaine was studied in rats (n = 6/group) with free access to standard (5.7% fat) or high fat (34.3%) chow or restricted access to high fat chow (body weight matched to rats eating standard chow). RESULTS: After 1 week of eating high fat chow (free or restricted access), sensitivity to cocaine was significantly increased in adolescent and adult rats, compared with rats eating standard chow. Sensitivity to cocaine was also increased in adolescent rats with restricted, but not free, access to high fat chow for 4 weeks. When adolescent and adult rats that previously ate high fat chow ate standard chow, sensitivity to cocaine returned to normal. In adolescent and adult female rats eating high fat chow, but not those eating standard chow, sensitivity to cocaine increased progressively over once weekly tests with cocaine (i.e., sensitization) in a manner that was not statistically different between adolescents and adults. CONCLUSIONS: These results show that eating high fat chow alters sensitivity of female rats to acutely administered cocaine and also facilitates the development of sensitization to cocaine. That the type of food consumed can increase drug effects might have relevance to vulnerability to abuse cocaine in the female population.

Corneal flap thickness and topography changes induced by flap creation during laser in situ keratomileusis.

PURPOSE: To determine the corneal flap thickness profile produced by 3 microkeratomes and the topographic changes induced by flap creation in laser in situ keratomileusis (LASIK). SETTING: Cornea and Refractive Surgery Unit, Instituto de Microcirugia Ocular de Barcelona, Autonoma University, Barcelona, Spain. METHODS: In this prospective consecutive nonrandomized comparative study, patients were divided into 2 groups. In Group 1 (75 eyes), 3 microkeratomes were used: Moria LSX One, Moria M2, and Amadeus (AMO); 25 eyes per microkeratome. Pachymetry was measured with a DGH pachymeter in the center of the cornea and 3.0 mm from the center at 4 cardinal points (superior, inferior, nasal, and temporal; 3 measurements at each point) before and after the cut. The flap thickness in each sector was calculated by subtracting the mean post-flap corneal thickness from the mean pre-flap corneal thickness. In Group 2 (33 eyes), the M2 microkeratome with a 130 microm plate was used to create a superotemporal hinged flap (9 eyes) or a superonasal hinged flap (24 eyes). The topographic change induced by the microkeratome cut was evaluated using 4 sequential data acquisitions by the Keratron Scout topographic unit (Optikon) before and immediately after the cut (before laser ablation). Cardinal and oblique astigmatism and change in the axis were calculated by vectorial analysis of the simulated keratometry. Topographic Zernike analysis was performed in a subgroup. RESULTS: With the LSX One microkeratome, the mean flap thickness was 151.7 microm centrally, 161.9 microm superiorly, 151.4 microm inferiorly, 156.1 microm temporally, and 167.5 microm nasally. There was no statistically significant difference between the areas studied (P<.05). With the M2, the mean flap thickness was 131.7 microm centrally, 155.5 microm superiorly, 146.7 microm inferiorly, 143.7 microm temporally, and 160.5 microm nasally. There was a statistically significant difference between flap thickness centrally and in the other areas (P>.05). With the Amadeus microkeratome, the mean flap thickness was 140.0 microm centrally, 152.5 superiorly, 128.5 microm inferiorly, 145.0 microm temporally, and 147.0 microm nasally. Statistically significant differences (P>.05) were found in the 4 sectors of the flap. With vectorial analysis, there was no statistically significant difference between superonasal and superotemporal hinge placement in the cardinal and oblique components but there was a statistically significant difference in the axis change with both placements (P>.05). CONCLUSIONS: The LSX One microkeratome was the most predictable. A significant difference was noted in all sectors except superiorly with the M2 and in all sectors with the Amadeus. No differences between nasal and superior hinge placement were found with the M2. Topographic Zernike analysis demonstrated a difference in the orientation of the induced coma as a function of hinge position.

Secondary Artisan-Verysise aphakic lens implantation.

PURPOSE: To evaluate efficacy, predictability and safety of Artisan-Verysise intraocular lens (IOL) secondary implantation for aphakia correction. SETTING: Instituto de Microcirugía Ocular, and Autonoma University of Barcelona, Barcelona, Spain. METHODS: Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), manifest refraction, endothelial cell count, and clinical complications were evaluated. Sixteen consecutive eyes of 14 patients with aphakia were submitted to surgery. Postoperative examinations were done at 6 weeks, 6 months, 1 year, and every year for at least 3 years. An iris-supported Artisan-Verysise IOL was implanted for aphakia correction. RESULTS: Thirty-six months after Artisan-Verysise lens implantation, BSCVA was 20/40 or better in 6 eyes (37.5%). Preoperatively, 5 eyes had the same BSCVA (31.25%). Mean postoperative spherical equivalent (SE) was 0.46 diopter (D). Mean endothelial cell loss was 10.9% 36 months postoperatively. The cell loss occurred predominantly during the first year (7.78%). Cystoid macular edema was observed in 2 cases, 1 of them associated with chronic unresponsive low intraocular pressure. No other serious complications were observed. CONCLUSION: Artisan-Verysise IOL implantation seems a safe, predictable, and effective option for aphakic eyes without capsule support.

Confocal microscopy of corneas with an intracorneal lens for hyperopia.

PURPOSE: We evaluated short-term results and confocal microscopic corneal changes following intracorneal lens implantation. METHODS: In six eyes of three patients with hyperopia between +3.00 and +6.00 diopters (D), an intrastromal hydrogel lens (Permavision, Anamed, Anaheim, Calif) was implanted. Mean baseline hyperopia was +3.90 D. Manifest refraction, uncorrected visual acuity, and spectacle-corrected visual acuity were evaluated. We also performed confocal real-time microscopy with a water immersion objective. Corneal optical sections were recorded and reviewed frame by frame. Examinations were done at months 3, 6, and 12 after intracorneal lens implantation. RESULTS: After surgery, the spherical equivalent refraction was within +/- 0.50 D in 83% (five of six eyes) at 3 months and 100% (six eyes) at 6 and 12 months. Uncorrected visual acuity (UCVA) at 3 months was within 20/40 or better in 67% (four eyes) and in 100% (six eyes) at 6 and 12 months; no eyes had 20/20 or better UCVA at 3 and 6 months. One eye (17%) had 20/20 or better UCVA at 12 months. On confocal microscopy, one eye had an amorphous deposit adjacent to the lens and presumed fibroblastic activity in the same stromal area at 6 months, which was non-progressive up to 12 months. CONCLUSION: Intracorneal lenses may be a treatment option for correction of spherical hyperopia. Predictability must be improved but results in these six eyes were stable up to 1 year. Confocal miscroscopy confirmed biocompatibility and showed no abnormal changes, except two spots of hypercellularity in one eye.

Phaco rolling technique.

We describe a phacoemulsification technique for soft and medium-hard cataracts to decrease phaco time and enhance the safety of the procedure. After conventional hydrodissection and hydrodelamination are performed, a 15- or 30-degree phaco tip is positioned on the peripheral lens beside the capsulorhexis edge and in contact with the nucleus-epinucleus interface. The lens is then aspirated onto the phaco tip. Phacoemulsification is started with the ultrasound energy level limited to 15% to 25% depending on the nuclear hardness and with linear aspiration power up to 250 mmHg. The phaco tip is slightly displaced to the vertex of the pupil to keep it occluded, and the lens is rotated. The phaco tip is placed in the same area and a modified manipulator used to keep the lens in a horizontal position during rotational movement. The small, hard, central nucleus is usually emulsified at the end.

Intracorneal ring segments after laser in situ keratomileusis.

PURPOSE: To evaluate the safety and efficacy of intracorneal ring segments (ICRS) for correction of residual refractive error in patients previously operated with laser in situ keratomileusis (LASIK). METHODS: Thirteen postoperative LASIK eyes (eight patients) with residual myopic refractive error underwent implantation with INTACS (Keravision) intracorneal ring segments. Correction of the residual error was the first goal, but also improved best spectacle-corrected visual acuity was obtained by correcting residual irregular astigmatism. RESULTS: Mean spherical equivalent refraction improved from -3.25 to +0.75 D and mean uncorrected visual acuity improved from 0.2 to 0.6 after ICRS insertion. Best spectacle-corrected visual acuity remained stable or improved; no eyes lost lines of corrected visual acuity. In one of the 13 eyes, the intracorneal ring segments were removed because of progressive stromal melting. CONCLUSIONS: The use of corneal ring segments in selected eyes with residual myopic refractive errors after LASIK was safe and effective.

Artisan toric phakic intraocular lens for the correction of high astigmatism.

PURPOSE: To evaluate efficacy, predictability, and safety of Artisan toric phakic intraocular lens (Ophtec, Groningen, The Netherlands) implantation for the correction of astigmatism higher than 2 diopters. DESIGN: Interventional case series. METHODS: This prospective study included 27 eyes of 16 patients with a mean preoperative spherical equivalent of -11.78 +/- 6.24 diopters and a mean preoperative astigmatism of -3.43 +/- 0.81. The Artisan phakic intraocular lens was inserted in the anterior chamber through a posterior corneal incision; the technique is similar to the implantation of the classical Artisan lens, but in these cases it is particularly important to secure the lens accurately in the correct axis. The main parameters evaluated in this study were uncorrected visual acuity, best-corrected visual acuity, refraction, and endothelial cell count. RESULTS: Twelve months after the implantation of the Artisan toric phakic intraocular lens, 62.90% of the eyes were within +/-0.50 diopters. of emmetropia and 96.20% within +/-1.0 diopters. Seventy percent of the eyes gained 1 or more Snellen lines from their preoperative best-corrected visual acuity, and 11.11% lost 1 Snellen line. Mean endothelial cell count increased 2.9%. Mean of the parallel and orthogonal components of cylinder correction were 1.97 diopters and 0.10 diopters, respectively, of the intended cylinder change. The mean of axis alignment error was 10.53 degrees. No serious complications were observed. CONCLUSION: Artisan toric phakic intraocular lens implantation appears to be a safe and predictable method for the correction of high levels of astigmatism.

Conjunctival healing after amniotic membrane graft over ischemic sclera.

PURPOSE: To present a case of chemical injury associated with calcification and severe conjunctival and scleral ischemia, in which tissue regeneration was achieved using an amniotic membrane graft. METHODS: A 65-year-old man presented to our department 8 weeks after suffering a chemical injury of his left eye with sulfuric acid. There was extensive calcification of the cornea and conjunctiva, associated with severe ischemia of the adjacent sclera. After resection of the calcified tissue and nonviable tissue, amniotic membrane was grafted to cover the extensive zone of scleral ischemia. RESULTS: In the weeks following grafting, slow epithelialization and revascularization was observed over the amniotic membrane, stemming from the surrounding healthy conjunctiva. CONCLUSION: Although the presence of ischemia at the base of the graft has been considered a contraindication for amniotic membrane transplantation, this case demonstrates that, provided that the surrounding tissue is not affected, a graft may be useful. In such cases an amniotic membrane graft could be attempted before other alternatives, such as conjuntival or oral mucosal autografts.

Phacoemulsification of the crystalline lens and implantation of an intraocular lens for the correction of moderate and high myopia: four-year follow-up.

PURPOSE: To assess the safety of lens extraction and intraocular lens (IOL) implantation in patients with high myopia treated for initial lens opacity and/or refractive indications. SETTING: Instituto de Microcirugía Ocular de Barcelona, Barcelona, Spain. METHODS: This retrospective nonrandomized case series study comprised 44 eyes of 30 consecutive myopic patients who had surgery because of initial lens opacity and/or refractive indications during a 2-year period. In each case, phacoemulsification was performed using an ultrasonic technique and an IOL was implanted in the capsular bag. The patients were seen preoperatively to evaluate retinal pathology. They also had a complete ophthalmologic evaluation that included detailed indirect ophthalmoscopy. All patients were followed at regular intervals. The main outcome measures were preoperative and postoperative spherical equivalent (SE), the incidence of posterior capsule opacification (PCO) and the need for capsulotomy, and the incidence of retinal complications. RESULTS: In all eyes, the surgery was uneventful. The mean patient age at surgery was 42.83 years; the mean preoperative SE was -15.77 diopters (D) and the mean postoperative SE, -1.05 D. No eye required preoperative peripheral retinal photocoagulation. Twenty-five eyes (56.8%) had PCO and had a neodymium:YAG laser capsulotomy. One eye had a retinal tear 14 months after surgery and was treated with focal photocoagulation. The mean endothelial cell loss was 2.1% during the first postoperative year. Two eyes had an immediate postoperative intraocular pressure (IOP) rise, 1 with an inflammatory membrane and the other with corneal edema; both resolved with topical treatment. One eye with elevated IOP and a bad response to medical treatment had argon laser trabeculoplasty. No eye had a retinal detachment during the follow-up. CONCLUSION: With a thorough preoperative ophthalmologic evaluation and uneventful surgery, patients who have phacoemulsification and IOL implantation for the correction of myopia have a satisfactory chance of obtaining good visual results with few complications.