LASIK Eye Surgery

A report in the February issue of Archives of Ophthalmology, one of the JAMA/Archives journals, indicates: ‘Swelling commonly occurs in the corneas of mountain climbers, but does not appear to affect vision at altitudes of up to 6,300 meters (about 20,670 feet) … ‘

A Media Release issued on February 8 by JAMA/Archives journals informs: Read more »

Tags: 20 300 meters 6 670 feet acclimate acute mountain sickness affect vision after after descent altitudes amount of decrease appear aqueous humor- Archives of Ophthalmology ascending ascending paths ascents atmospheric conditions blood oxygen levels changes China climb conditions consecutive decrease corneal oxygen levels corneal swelling corneal thickness corneas decrease decreased delivery of oxygen Department of Ophthalmology different do not appear exposure extreme extreme altitudes eyeball fluid fluid inside formation front of the eye greater hazardous health healthy high-altitude cerebral edema high-altitude climbing high-altitude climbs hypobaric inadequate increase increased increasing altitude induce greater damage iri iris JAMA-Archives journals lead lowlanders Mount Muztagh Ata mountain climbers mountain climbing mountaineering mountains ophthalmology oxygen saturation oxygen supplie paralleled popular recreational sport shorter acclimatization time shorter time susceptibility swelling Swiss Society of Mountain Medicine Switzerland symptoms thickness transparent membrane University Hospital Zurich vision loss visual acuity western China

A report in the February issue of Archives of Ophthalmology, one of the JAMA/Archives journals, indicates: ‘Glaucoma patients who take medication for the condition appear to have a reduced likelihood of death … ‘

A Media Release issued on February 8 by JAMA/Archives journals informs: Read more »

Tags: access to care Archives of Ophthalmology association between beta-antagonist clinical compare conditions death demographic information elevated pressure employers eye family members glaucoma glaucoma and death glaucoma patients health care health care professionals information JAMA-Archives journals managed care network medicatio prostaglandin analogue reduced reduced likelihood risk surgery suspected glaucoma topical

• “… whether long-term visual experience with irregular optical blur compensates for the impact of higher order aberration on visual performance in keratoconic (KC) eyes.”¹

Researchers from Institute of Optics, University of Rochester, Rochester, New York, United States; have presented an article titled: “Neural compensation for long-term asymmetric optical blur to improve visual performance in keratoconic eyes.”

The researchers from Rochester, New York, have concluded:

• “In keratoconic eyes, the neural visual system compensates for long-term visual experience with an asymmetrically blurred retinal image, resulting in improved visual performance.”

The researchers from Rochester, New York, have also noted:

• “Aberrations, high (100%) and low (20%) contrast tumbling ‘E’ visual acuity (VA) were measured in 4 moderate KC eyes wearing their own prescribed soft toric contact lenses, over a 6-mm pupil.”
• “Same 3 emmetropic normal eyes were recruited to measure VA with each of 4 KC eye’s aberration for comparison.”
• “An adaptive optics system was used to correct the normal eye’s aberration and induce KC eye’s aberration on them simultaneously during vision testing.”
• “The magnitude of neural compensation was defined as the improvement in VA in each KC eye compared to the 3 normal eyes with KC aberrations.”
• “Mean total and higher order rms errors in the KC eyes with their contact lens were 2.72+/-0.83 mum and 1.36+/-0.29 mum for a 6 mm pupil, respectively.”
• “Residual rms wavefront error in induction of KC aberrations on normal eyes was around 0.1 mum in all cases.”
• “Each KC eye had statistically better high (p<0.02) and low (p<0.03) contrast VA than the 3 normal eyes.”
• “Mean compensation for high contrast VA in logMAR was 0.12+/-0.09, corresponding to an improvement of 23.8 %.”
• “A similar result was obtained for low contrast VA also.”
• “The magnitude of compensation increased with the severity of KC aberrations.”

(1) Sabesan R, Yoon G: Neural compensation for long-term asymmetric optical blur to improve visual performance in keratoconic eyes. Invest Ophthalmol Vis Sci. 2010 Feb 3; (Article in Press)

Tags: aberration aberrations adaptive asymmetric blur asymmetric optical blur asymmetrically blurred comparison compensates high contrast higher order aberration higher order rms errors hoas impact improve improvement induction institute of optics irregular irregular blur kc aberrations kc eyes keratoconic eyes long-term long-term experience low contrast magnitude mean compensation neural compensation neural vision neural visual system New York normal eyes optical blur optics system prescribed soft toric contact lenses residual rms retinal image Rochester severity soft contact lenses soft contacts soft toric contact lenses toric contact lenses toric contacts tumbling -039e-039 visual acuity University of Rochester vision visual experience visual performance wavefront error

• “To compare the topographic features of eyes treated with photorefractive keratectomy (PRK) for myopia using two different excimer lasers.”¹

Researchers from Department of Ophthalmology, Ajou University School of Medicine, Suwon, Korea; and from Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea; have presented an article titled: “Comparison of the topographic ablation zone after photorefractive keratectomy for myopia using two different excimer lasers.”

The researchers from Suwon and Seoul have concluded:

• “There was a difference between the programmed and postoperative topographic diameters of the ablation zone.”
• “The postoperative ablation zone differed in shape and size according to the type of excimer laser.”

The researchers from Suwon and Seoul have also noted:

• “A total of 65 eyes in 39 patients treated with PRK (6.0-mm optical zone) using Technolas 217C and VISX S4 excimer lasers were evaluated retrospectively to determine the size of the topographic ablation zone.”
• “The zones ablated using the VISX S4 had shorter diameters in both axes (-0.89+/-0.73, -1.59+/-0.49 mm; both P=0.00), whereas those ablated using the Technolas 217C had a longer diameter in the major axis (0.96+/-0.63 mm; P=0.00) and a shorter diameter in the minor axis (-0.39+/-0.59 mm; P=0.00).”
• “The Technolas 217C group tended to have oval cuts in comparison with the VISX S4 group, and the difference between the programmed (6.0 mm) and topographic diameters was significant in both groups.”

(1) Ahn J, Yang H, Lew HM, Kim EK: Comparison of the topographic ablation zone after photorefractive keratectomy for myopia using two different excimer lasers. Eye (Lond). 2009 Jul 24; (Article in Press)

Tags: ablation zone Ajou University School of Medicine compare Corneal Dystrophy Research Institute Department of Ophthalmology difference excimer laser eyes treated Korea longer diameter major axis minor axis myopia nearsighted oval cuts photorefractive keratectomy postoperative postoperative topographic diameters PRK programmed diameter Seoul shape shorter diameter size Suwon topographic features two different excimer lasers two lasers type of excimer laser Yonsei University College of Medicine zone

Jeffrey Heier MD, from Ophthalmic Consultants of Boston, has said:

• “As P529 is an inhibitor of both the TORC1 and TORC2 arms ultimately controlling the PI3K/Akt/mTOR pathway it would be expected to have broad activity as an anti-angiogenic agent and further inhibit vascular permeability, two aspects that make a compelling story for clinical studies in AMD.
•  We look forward to working with Paloma Pharmaceuticals on this interesting approach to wet AMD …”

More from a Release dated February 4, sourced from Paloma Pharmaceuticals Inc:
Read more »

Tags: aberrant age-related macular degeneration Alzheimers angiogenesis angiogenic anti-angiogenic agent antiviral diseases atopic dermatitis Boston cascade cataract computational design cornea cytokines diabetic retinopathy doses dual inhibitor edema epilepsy eye care eye trauma fibrotic diseases glaucoma hemorrhage d Huntingtons inhibit inhibitor intravitreal Jamaica Plains laser LASIK Massachusetts medicinal chemistry mTOR inhibitor mTOR pathway mTOR signal transduction pathway neovasculature non-steroidal ocular disease Ophthalmic Consultants of Boston orbital plastics Parkinsons pathological pediatrics PI3K-Akt-mTOR pathway pro-angiogenic pro-angiogenic factors protein complexes psoriasis pulmonary fibrosis rapamycin renal fibrosis retina retinal vessels schizophrenia skin diseases small molecule drug subconjunctival surgical treatment synthetic synthetic chemistry therapeutic therapeutic target TORC1 TORC1 antagonists TORC2 vascular endothelial growth factor vascular leakage vascular permeability VEGF wet AMD

• “To determine the variations in corneal thickness values, keratometry readings, and anterior chamber depths (ACD) during the menstrual cycle of young women using the noncontact Scheimpflug imaging technique.”

Researchers from Noor Ophthalmology Research Center, Noor Eye Hospital; and the Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran; have presented an article titled: “Changes in corneal thickness, curvature, and anterior chamber depth during the menstrual cycle.” ¹

The researchers from Noor Ophthalmology Research Center, Noor Eye Hospital; and the Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran; have also noted:

• “Fourteen women with regular menstrual cycles who were not taking contraceptive pills were enrolled and had measurements taken every other day during a full menstrual cycle, starting from the first day.”
• “None used contact lenses or regular medication, and none had systemic disease or history of eye surgery.”
• “The thickness at the centre, superior, inferior, temporal, nasal, and thinnest point of the cornea, the keratometry readings, and the ACD values measured with the Pentacam were recorded.”
• “We used data on days 1, 3, and 5 of the studied cycle, and counting backwards, 2, 4, 6, 12, 14, and 16 days before the first day of the next cycle.”
• “The mean differences between 2 points of time were not statistically significant (p > 0.05) for any variable.”
• “The mean difference between any 2 paired thickness measurements was less than 5.0 microm.
• “Contrary to our expectations and previous findings using ultrasound pachymetry, we found no clinically or statistically significant differences between the repeated measurements with the Pentacam.”
• “This could indicate that the Pentacam is a clinical tool with less variability when performing serial measurements and follow-up examinations.”

(1) Hashemi H, Mehravaran S, Rezvan F: Changes in corneal thickness, curvature, and anterior chamber depth during the menstrual cycle. Can J Ophthalmol. 2010 Feb;45(1):67-70.

Tags: anterior chamber depth any variable changes contact lenses contacts contraceptive pills contrary corneal thickness corneal thickness values counting backwards curvature differences every other day d examinations eye surgery Farabi Eye Hospital first day follow-up imaging inferior Iran keratometry readings menstrual cycle nasal next cycle noncontact noncontact Scheimpflug imaging technique Noor Eye Hospital Noor Ophthalmology Research Center our expectations previous findings regular medication regular menstrual cycles repeated measurements serial measurements statistically significant superior systemic disease Tehran Tehran University of Medical Sciences temporal thickness at the centre thinnest point ultrasound pachymetry variations young women

• “… whether hypo-osmotic saline drops can improve contact lens associated discomfort and dryness by decreasing contact lens osmolality.”

Researchers from Vision Cooperative Research Centre, Sydney, New South Wales, Australia; Institute for Eye Research, Sydney, New South Wales, Australia; and School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia; have presented an article titled: “Role of hypo-osmotic saline drops in ocular comfort during contact lens wear.” ¹

The researchers from Sydney have concluded:

• “Hypo-osmotic saline drops were preferred by a greater number of subjects and contact lens osmolality tended to be lower with the use of hypo-osmotic saline.”
• “Hypo-osmotic drops have the potential to decrease contact lens osmolality which in turn may help improve ocular comfort.”
• “This has possible impact on the practitioners’ choice of the lens rewetting drop recommended and the design of future lens rewetting drops.”

The researchers from Sydney have also noted:

• “Fifteen symptomatic subjects wore Lotrafilcon A lenses bilaterally for 6h on two different days.”
• “According to randomisation, hypo-osmotic (280mmol/kg) or hyper-osmotic (380mmol/kg) saline drops were applied four times during each day and ocular symptoms, tear film and contact lens parameters, and contact lens osmolality were assessed.”
• “Sixty percent of the subjects preferred the hypo-osmotic saline drops, compared to 33%, who preferred the hyper-osmotic ones.”
• “Subjects experienced significantly less dryness and lens awareness with hypo-osmotic saline drops compared to hyper-osmotic ones (p<0.05).”
• “Using the hypo-osmotic drops, there was a trend for decreased contact lens osmolality from 379 to 343mmol/kg (p=0.06).”
• “There were no differences in lipid layer, non-invasive tear film break-up time, lens surface wettability, lens water content after wear, lens movement on eye or ocular staining and indentation between saline drops (all p>0.05).”
• “Interestingly, the difference in contact lens osmolality between drops did not reflect the osmolality difference between the two saline drops.”

(1) Stahl U, Willcox M, Stapleton F: Role of hypo-osmotic saline drops in ocular comfort during contact lens wear. Cont Lens Anterior Eye. 2010 Jan 29; (Article in Press)

Tags: Australia contact lens osmolality contact lens parameters contact lens wear decreasing discomfort dryness eye drops four times greater number help improve hyper-osmotic eye drops hypo-osmotic eye drops hypo-osmotic saline hypo-osmotic saline drops hypo-osmotic saline eye drops improve contact lens indentation between saline drops Institute for Eye Research lens awareness lens movement on eye lens rewetting lens rewetting drop lens surface wettability lens water content lenses bilaterally less dryness lipid layer New South Wales non-invasive ocular comfort ocular staining osmolality preferred rewetting drops saline eye drops School of Optometry and Vision Science Sydney tear film tear film break-up time University of New South Wales Vision Cooperative Research Centre

• “To evaluate and compare visual, refractive, and corneal aberrometric outcomes after implantation of 2 types of intrastromal corneal ring segments (ICRS) in eyes with early to moderate ectatic disease.”¹

Researchers from Vissum Corporation-Instituto Oftalmológico de Alicante, in Alicante, Spain; Universidad Miguel Hernández, in Alicante, Spain; and Ain Shams University, in Cairo, Egypt; have presented an article titled: “Corneal aberrometric and refractive performance of 2 intrastromal corneal ring segment models in early and moderate ectatic disease.”

The researchers from Alicante, Spain and Cairo, Egypt; have concluded:

• “Astigmatism correction in early to moderate ectatic corneas was more limited with the Intacs ICRS, which induced negative primary spherical aberration in the initial postoperative period.”

The researchers from Alicante, Spain and Cairo, Egypt; have also noted:

• “… retrospective analysis comprised consecutive eyes with grade I or grade II corneal ectasia (keratoconus, pellucid marginal degeneration, ectasia after laser in situ keratomileusis) that had Intacs (Group I) or KeraRings (Group K) ICRS implantation using femtosecond technology.”
• “Group I had 17 eyes and Group K, 20 eyes.”
• “One month postoperatively, there was a statistically significant reduction in sphere in both groups (P</=.02).”
• “At 6 months, there was a statistically significant reduction in manifest cylinder in Group K that was consistent with the significant reduction in corneal astigmatic aberration (both P = .04).”
• “The uncorrected distance visual acuity increased significantly in Group K (P = .04) but not in Group I; 41.18% of eyes in Group I and 52.94% in Group K gained 1 or more lines of corrected distance visual acuity.”
• “Both groups had significant corneal flattening (P</=.02).”
• “At 1 month, the mean primary spherical aberration was -0.17 mum +/- 0.52 (SD) in Group I and 0.40 +/- 0.35 mum in Group K; the difference was statistically significant (P<.01).”

(1) Piñero DP, Alió JL, El Kady B, Pascual I: Corneal aberrometric and refractive performance of 2 intrastromal corneal ring segment models in early and moderate ectatic disease. J Cataract Refract Surg. 2010 Jan;36(1):102-109.

Tags: after implantation Ain Shams University Alicante astigmatism Cairo consecutive eyes corneal aberrometric outcomes corneal astigmatic aberration corneal flattening correction early ectatic corneas ectasia after laser in situ keratomileusis ectasia after LASIK ectatic disease Egyp Egypt femtosecond femtosecond laser femtosecond technology in Cairo induced initial postoperative period intrastromal corneal ring segment intrastromal corneal ring segments keratoconus manifest cylinder mean primary spherical aberration moderate ectatic disease negative primary spherical aberration pellucid marginal degeneration reduction in sphere refractive performance Spain Universidad Miguel Hernández Vissum Corporation-Instituto Oftalmológico de Alicante

• “A 29-year-old man, with no significant past medical history, was in his usual state of health until the afternoon of admission.”¹
• “The patient was seated at work eating lunch when he suddenly noticed that his vision became blurry.”
• “He covered his right eye and had no visual difficulty but noted blurry vision upon covering his left eye.”
• “At this point, the patient tried to stand up, but had difficulty walking and noticed he was “falling toward his left.” Facial asymmetry when smiling was also appreciated.”

Researchers from Section of Cardiology, Louisiana State University Health Sciences Center, School of Medicine, New Orleans, USA; have presented an article titled: “Clinical case of the month. A 29-year-old man with acute onset blurry vision, weakness, and gait abnormality. Stroke.”

The researchers from New Orleans, Louisiana, have also noted:

• “The patient denied any alteration in mental status, confusion, antecedent or current headaches, aura, chest pains, or shortness of breath.”
• “He was not taking any prescribed medications and had no known allergies.”
• “The patient denied any prior hospitalization or surgery.”
• “He denied use of tobacco, alcohol, or illicit drugs, and worked as a maintenance worker in a hotel.”
• “His family history is remarkable for his father who died of pancreatic cancer in his 50s and his mother who died of an unknown heart condition in her late 40s.”
• “Vital signs on presentation to the emergency department included temperature of 97.6 degrees F; respiratory rate of 18 per minute; pulse of 68 per minute; blood pressure of 124/84 mmHg; pulse oximetry of 99% on ambient air.”
• “His body mass index was 24 and he was complaining of no pain.”
• “The patient had no carotid bruits and no significant jugular venous distention.”
• “Cardiovascular exam revealed a regular rate and rhythm with no murmurs.”
• “Neurological exam revealed left-sided facial weakness, dysarthria, and preserved visual fields.”
• “He was able to furrow his brow.”
• “Gait deviation to the left was present, and Romberg sign was negative.”
• “Deep tendon reflexes were 2+ throughout, and no other focal neurological deficit was present.”
• “The patient was admitted to the hospital with a diagnosis of stroke.”
• “Electrocardiogram, fasting lipid profile, computed tomography (CT) scan of head, magnetic resonance imaging (MRI) of head and neck, and transthoracic echo with bubble study were ordered.”
• “The initial head CT did not reveal bleeding.”
• “He was started on aspirin (ASA).”
• “On the second hospital day, the symptoms improved with resolution of dysarthria.”
• “His ataxia had also improved.”
• “Fasting lipid profile revealed mildly elevated low-density lipoprotein and total cholesterol.”
• “His head MRI revealed an acute right thalamic stroke.”
• “Echocardiography was significant only for a patent foramen ovale (PFO) with transit of agitated saline “bubbles” from right atrium to left heart within three cardiac cycles (Figure).”
• “Doppler ultrasound of extremities revealed no evidence of deep venous thrombosis.”
• “A complete resolution of symptoms occurred by the third hospital day.”
• “The patient was discharged on full dose aspirin and a statin and was referred for consideration of enrollment in a PFO closure versus medical management trial.”

(1) Thoppil D, Ali MJ, Jain N, Kamboj S, Subramaniam P, Lopez FA: Clinical case of the month. A 29-year-old man with acute onset blurry vision, weakness, and gait abnormality. Stroke. J La State Med Soc. 2009 Nov-Dec;161(6):308-10, 312.

Tags: alcohol alteration ambient air antecedent antecedent headaches aspirin and statin ataxia aura bleeding blood pressure blurred vision blurry vision body mass index bubble study carotid bruit chest pains complaining of no pain computed tomography scan of head confusion covering his left eye current headaches deep tendon reflexes difficulty walking dysarthria eating lunch facial asymmetry facial weakness falling toward left fasting lipid profile furrow his brow gait abnormality gait deviation head and neck headache jugular venous distention known allergies left-sided Louisiana low-density lipoprotein magnetic resonance imaging medical management mental status mildly elevated murmurs New Orleans pain pancreatic cancer PFO closure preserved visual fields pulse pulse oximetry regular rate respiratory rate rhythm right seated at work shortness of breath started on aspirin statin stroke temperature thalamic stroke tobacco total cholesterol transthoracic echo tried to stand up unknown heart condition usual state of health vision became blurry when smiling

• “… to evaluate whether addition of omega-3 fatty acids or increase in aspirin dose improves response to low-dose aspirin among patients who are aspirin resistant.”¹

Researchers from Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Methodist DeBakey Heart Center, The Methodist Hospital, Houston, Texas, USA; and Cardiology Department, Rabin Medical Center, Petah Tikva, Israel; have presented an article titled: “Treatment of Aspirin-Resistant Patients With Omega-3 Fatty Acids Versus Aspirin Dose Escalation.”

The researchers from Tel Aviv, Houston and Petah Tikva; have concluded:

• “Treatment of aspirin-resistant patients by adding omega-3 fatty acids or increasing the aspirin dose seems to improve response to aspirin and effectively reduces platelet reactivity.”

The researchers from Tel Aviv, Houston and Petah Tikva; have also noted:

• “Low response to aspirin has been associated with adverse cardiovascular events.”
• “However, there is no established therapeutic approach to overcome aspirin resistance.”
• “Omega-3 fatty acids decrease the availability of platelet arachidonic acid (AA) and indirectly thromboxane A2 formation.”
• “Patients (n = 485) with stable coronary artery disease taking low-dose aspirin (75 to 162 mg) for at least 1 week were screened for aspirin response with the VerifyNow Aspirin assay (Accumetrics, San Diego, California).”
• “Aspirin resistance was defined by >/=2 of 3 criteria: VerifyNow score >/=550, 0.5-mg/ml AA-induced aggregation >/=20%, and 10-mumol/l adenosine diphosphate (ADP)-induced aggregation >/=70%.”
• “Thirty patients (6.2%) were found to be aspirin resistant and randomized to receive either low-dose aspirin + omega-3 fatty acids (4 capsules daily) or aspirin 325 mg daily.”
• “After 30 days of treatment patients were re-tested.”
• “Both groups (n = 15 each) had similar clinical characteristics.”
• “After treatment significant reductions in AA- and ADP-induced aggregation and the VerifyNow score were observed in both groups.”
• “Plasma levels of thromboxane B2 were also reduced in both groups (56.8% reduction in the omega-3 fatty acids group, and 39.6% decrease in the aspirin group).”
• “Twelve patients (80%) who received omega-3 fatty acids and 11 patients (73%) who received aspirin 325 mg were no longer aspirin resistant after treatment.”

(1) Lev EI, Solodky A, Harel N, Mager A, Brosh D, Assali A, Roller M, Battler A, Kleiman NS, Kornowski R: Treatment of Aspirin-Resistant Patients With Omega-3 Fatty Acids Versus Aspirin Dose Escalation. J Am Coll Cardiol. 2010 Jan 12;55(2):114-121.

Tags: adding adverse aspirin aspirin dose aspirin resistance aspirin resistant capsules daily Cardiology Department cardiovascular events decrease the availability Houston improve response increasing induced aggregation Israel low-dose aspirin Methodist DeBakey Heart Center Methodist Hospital omega-3 fatty acids Petah Tikva platelet aggregation platelet arachidonic acid Rabin Medical Center response response to aspirin Sackler Faculty of Medicine Tel Aviv Tel Aviv University Texas thromboxane A2 formation USA