Determination of Corneal Power after Refractive Surgery with Excimer Laser: A Concise Review.

Refractive surgery with excimer laser has been a very common surgical procedure worldwide during the last decades. Currently, patients who underwent refractive surgery years ago are older, with a growing number of them now needing cataract surgery. To establish the power of the intraocular lens to be implanted in these patients, it is essential to define the true corneal power. However, since the refractive surgery modified the anterior, but not the posterior surface of the cornea, the determination of the corneal power in this group of patients is challenging. This article reviews the different sources of error in finding the true corneal power in these cases, and comments on several approaches, including the clinical history method as described originally by Holladay, and a modified version of it, as well as new alternatives based on corneal tomography, using devices that are able to measure the actual anterior and posterior corneal curvatures, which have emerged in recent years to address this issue.

VISUAL OUTCOMES, CONTRAST SENSITIVITY, AND SATISFACTION WITH MULTIFOCAL INTRAOCULAR LENS BLENDED TECHNIQUE: LATE MID-TERM RESULTS.

PURPOSE: To describe clinical visual outcomes, spectacle independence, and patient satisfaction after cataract surgery with blending implantation of ReSTOR (Alcon laboratories) multifocal intraocular lenses. MATERIAL AND METHODS: A single-arm, non-randomized prospective study assessed patients undergoing cataract surgery with ReSTOR® +2.50 intraocular lens in the dominant eye and +3.00 add in the fellow eye between January 2015 to January 2020. RESULTS: In total, 47 patients (94 eyes) were enrolled, 28 women and 19 men. The average age at surgery time was 64 ±8 years, average postoperative follow-up was 45.4 ±7.0 months, with a minimum of 18.9 months. Postoperative binocular uncorrected distance visual acuity (UDVA) was on average 0.07 logMar (Snellen 20/24), uncorrected binocular intermediate visual acuity at 65 cm was 0.07 logMar (20/24), uncorrected binocular near visual acuity at 40 cm was 0.06 logMar (20/23). Contrast sensitivity under photopic and scotopic conditions, with and without glare, remained at the upper limit of normality. 98% of patients were quite satisfied or very satisfied. 87% did not require glasses for any activities, either at distant vision, nor at near vision. CONCLUSIONS: Cataract surgery with ReSTOR® IOL blended vision showed medium-term satisfactory visual results, achieving spectacle independence and a high level of satisfaction.

DETERMINATION OF FACTORS ASSOCIATED WITH LONG-TERM ENDOTHELIAL LOSS AND REFRACTIVE RESULT IN PATIENTS WITH ARTISAN PHAKIC LENS.

PURPOSE: To determine the changes in endothelial cell density, refractive results, and risk factors associated with endothelial loss in patients with irisclaw phakic intraocular lenses for myopia/myopic astigmatism (Artisan). METHODOLOGY: Data collection was obtained from an existing database with information on patients with a phakic Artisan lens implant between 1998 and 2011 at the Virgilio Galvis Ophthalmology Centre, with at least 5 years of follow-up. As a second stage, an analysis was carried out to identify the change in endothelial cell density and its potential associated factors. RESULTS: A total of 80 eyes with myopic errors were included with a follow-up of 11.9 + 3.48 years. The percentage of total loss of endothelial cells was greater than 25% of the preoperative density in 43.8% of the eyes. A postoperative annual loss > 1.6% was found in 47.0% of the eyes with that information available. 41 eyes (51%) had final endothelial density < 2000 cells/mm2, and 7 (8.8%) eyes had endothelial cell density < 1000 cells/mm2. Among the variables studied, no associated factors for long-term endothelial loss were found. During the course of the study, 8 (10%) phakic intraocular lenses were explanted, including 3 with accelerated endothelial loss, and another 2 with cataract associated and a significantly low endothelial density. The last mean spherical equivalent was -0.81 (±1.01 D), and the final uncorrected distance visual acuity was 0.45 logMar (Snellen 20/56). CONCLUSION: Artisan-type phakic lenses are a good alternative for the correction of high myopic defects, with predictable refractive results in the long term. However, there is an increased loss of endothelial cells in the long term in a high percentage of patients. Strict postoperative follow-up, including endothelial evaluation, is required, and further studies are warranted.

Cystoid Macular Edema after an uncomplicated Gonioscopy- Assisted Transluminal Trabeculotomy on a previously vitrec- tomized patient.

Purpose: The main purpose of this study was to report a case of cystoid macular edema (CME) after gonioscopy-assisted transluminal trabeculotomy (GATT). Methods: We describe the case of a 73-year-old woman with ocular hypertension and history of cataract surgery combined with posterior vitrectomy and epiretinal membrane peeling 2 years before, who developed CME after uncomplicated GATT procedure. Results: Uneventful GATT surgery was performed in an eye with ocular hypertension. A month after GATT surgery, the patient com-plained of blurry vision. Best corrected visual acuity had deteriorated from 20/20 on Snellen chart, to 20/70. The patient was diagnosed with CME. Treatment with topical non-steroidal anti-inflammatory drug (NSAID) and topical corticosteroids for one month, and oral carbonic anhydrase inhibitor for one week achieved a total CME regression with recovery of a normal macular and foveal architecture. Conclusions: Surgery-induced CME may occur following stand-alone microinvasive glaucoma surgery (MIGS) such as GATT. It would be worthwhile to conduct studies to explore whether the prophylactic use of NSAID and corticosteroids is justified.

Estimation of ocular axial length with optometric parameters is not accurate.

Myopia is a worldwide major public concern, aside from the visual disturbance needing optical correction, myopia may be associated with open angle glaucoma, retinal detachment and myopic maculopathy. The higher the myopia the higher the risk for retinal associated comorbidities, and the axial length is the more important measure to estimate risk of visual impairment. Recently a formula to predict axial length using spherical equivalent and keratometry was proposed, with the intention of categorizing the risk of visual impairment with Tideman et al. classification. PURPOSE: To evaluate the accuracy of an axial length prediction formula in a Colombian population 8-17 years old. METHODS: Children from MIOPUR study with optical biometer axial length measure (AL), manifest refraction and keratometry were included in the analysis. Predicted axial length (PAL) was calculated with the prediction formula. A Bland-Altman assessment was conducted, and the concordance correlation coefficient was measured. Proposed classification of AL to establish risk of visual loss was used with measured AL and with PAL. The percentage of eyes misclassified was then established. RESULTS: A total of 2129 eyes were included in the analysis. Mean difference of axial length (actual AL minus PAL) was -0.516 mm (-1.559 mm - 0.528 mm). Concordance correlation coefficient (CCC) of 0.656 (IC95 0.636-0.675) was found between the real AL and PAL. PAL differed from measured AL by 1 mm or more in 16.58 %, and by 2 mm or more, in 0.61 % of the eyes. In myopic eyes, PAL was in average 0.426 mm longer than the AL actually measured with CCC of 0.714 (IC95 0.666-0.761). PAL differed from measured AL by 1 mm or more in 21.92 %, and by 2 mm or more, in 0.45 % of the myopic eyes. The study revealed that 15.03 % of all eyes, and 29.81 % of myopic eyes, were misclassified when PAL was used. CONCLUSIONS: The proposed axial length prediction formula was not accurate, and it did not adequately classify risk of visual impairment in myopic eyes in a group of Colombian children. We consider that it is not possible to predict the axial length based only on optometric data, such as the corneal radius of curvature and the spherical equivalent. This is very possibly related to the variability of crystalline lens power within a population.

SPONTANEOUS REGRESSION OF A PRIMARY IRIS STROMAL CYST IN A PATIENT WITH KERATOCONUS. A CASE REPORT.

PURPOSE: To report the rare case of a 29-year-old male with a history of keratoconus, who presented with a primary iris stromal cyst which eventually showed spontaneous regression. METHODS: Description of the clinical findings in the case of a 29-year-old male with a prior history of keratoconus, but no eye surgery or trauma, who consulted for an iris cyst in the left eye, diagnosed 9 months earlier. CASE REPORT: Slit-lamp examination revealed mild dyscoria, and a large cyst in the inferior quadrant of the iris. Ultrasound biomicroscopy and anterior segment optical coherence tomography of the left eye confirmed the presence of a giant iris cyst with thin walls, in contact with the corneal endothelium. Corneal endothelial cell density in the inferior cornea (close to the cyst) was 1805 cells/mm2 and 2066 cells/mm2 in the central area. After considering the risk of anterior chamber epithelial downgrowth following any surgical procedure of the cyst, the patient received conservative management. In the following months, the patient presented with 3 episodes of anterior uveitis, managed with topical corticosteroids. Finally, at approx. 21 months after the initial diagnosis, the cyst presented spontaneous regression. Anterior segment optical coherence tomography confirmed the absence of fluid inside the cyst remnants and the final endothelial cell densities evidenced endothelial cell loss (inferior cornea 738 cells/mm2 and central cornea 1605 cells/mm2). CONCLUSION: Conservative management should be considered in patients with cysts that show slow progression and are distant from the visual axis, in order to minimise the risk of complications following any surgical procedure of the cyst. In addition, the present case is one of the few of primary stromal iris cysts with spontaneous regression reported in the literature.

PHOTOREFRACTIVE SURGERY WITH EXCIMER LASER AND ITS IMPACT ON THE DIAGNOSIS AND FOLLOW-UP OF GLAUCOMA. A REVIEW.

Excimer laser refractive surgery is a procedure performed worldwide to solve refractive errors and reduce dependence on glasses or contact lenses. There has been an increase in the number of procedures performed around the world. Myopia is the most common indication for corneal photorefractive surgery. Myopic patients have a higher risk of developing some type of glaucoma in their lifetime, such as primary open-angle glaucoma and others. Refractive surgery ablates central corneal stromal tissue, altering its thickness and biomechanics, which in turn makes it difficult to accurately measure intraocular pressure (IOP), since it underestimates it. This underestimation of IOP may delay the diagnosis of de novo glaucoma in patients with a history of refractive surgery. Each patient who wishes to undergo corneal refractive surgery should undergo a thorough glaucoma examination in order to monitor and detect the possible development and / or progression of glaucoma. A very useful practical approach is to perform a series of IOP measurements before and after surgery, when the eye is already stable, and the difference between the averages of the two sets of readings can then be used as a personalised correction factor for postoperative IOP monitoring in that eye. Also, if there is any suspicion of a possible glaucoma, paraclinical tests, such as coherent optical tomography of the retinal nerve fibre layer (RNFL), visual fields and photos of the optic nerve should be requested. All this data prior to refractive surgery should be provided to these patients, so that they can save it and give it to their treating ophthalmologists in the future.

Antibiotic resistance profile in eye infections in a reference centre in Floridablanca, Colombia. / Perfil de resistencia antibiótica en infecciones oculares en un centro de referencia en Floridablanca, Colombia.

BACKGROUND AND OBJECTIVE: In view of the increasing bacterial resistance to antibiotics, it is necessary to determine it locally in order to serve as a guide in clinical management. The purpose of this study was to characterise the pattern of antibiotic sensitivity in cases of eye infections in a third level ophthalmological institution in Floridablanca (Colombia). MATERIALS AND METHODS: An observational cross-sectional study in which an analysis was made of the culture and antibiogram reports of specimens taken from cases of conjunctivitis, infectious keratitis, and endophthalmitis between January 2013 and June 2016. RESULTS: A total of 833 specimens were positive for bacteria. Considering both gram-positive and gram-negative microorganisms gentamicin, tobramycin, and ciprofloxacin showed high resistance rates (64.4%, 40.3%, and 29.1%, respectively). Moxifloxacin, vancomycin, imipenem, and gatifloxacin showed low percentages of resistance: 2.6%, 2.1%, 0.6%, and 0.4%, respectively. When comparing the results with previous studies in our institution, there was a decrease in sensitivity to the fourth-generation quinolones and imipenem, especially within the gram-negative ones. CONCLUSION: Fourth generation quinolones, imipenem and vancomycin continue to have a low in vitro resistance to bacteria that cause eye infections. However, there was a tendency to an increase in the resistance of gram-negative bacteria. Measures should be taken to try to control this phenomenon, and consider possible antimicrobial therapy alternatives to infections caused by these microorganisms.

Topical insulin in neurotrophic keratopathy after resection of acoustic neuroma. / Insulina tópica en queratopatía neurotrófica tras resección de neurinoma del acústico.

CASE REPORT: A patient with a history of surgical resection of an acoustic neuroma presented with involvement of both the left facial nerve and the left trigeminal nerve. She initially consulted for exposure keratitis, but two weeks later presented with an infectious keratitis. After taking the corneal sample, she presented with persistent epithelial defect, which did not respond to medical management. Topical insulin was indicated, and a decrease in the area of the lesion was seen in the following 5 days. A therapeutic contact lens was also placed at that time and finally, two weeks after the initiation of insulin, the epithelial defect completely closed. DISCUSSION: This was a complex case due to the confluence of facial paralysis, neurotrophic keratitis, and infectious keratitis, which finally had a successful outcome. Topical insulin can be an effective adjuvant therapy in cases of neurotrophic ulcers that do not respond to standard therapy.

Mycotic keratitis caused by Scedosporium apiospermum in an immunocompetent patient. / Queratitis micótica causada por Scedosporium apiospermum en paciente inmunocompetente.

CLINICAL CASE: A 51 year-old immunocompetent male was referred due to presenting with a large corneal ulcer with hypopyon in the right eye. Topical amphotericin B, fluconazole and moxifloxacin, as well as oral itraconazole were initially indicated. Following the report of mycotic structures on staining, topical natamycin was started. The result of the culture was reported two weeks later as, Scedosporium apiospermum (S. apiospermum), and topical voriconazole was then added. The response to treatment was very slow, and took five weeks after receiving triple therapy (natamycin, voriconazole and fluconazole) and one dose of intrastromal voriconazole, for the hypopyon to disappear. The final outcome was successful, achieving healing of the ulcer. The patient is waiting for a corneal transplant. DISCUSSION: A microbiological study is essential in patients in whom fungal keratitis is suspected. The treatment of choice against S. apiospermum is with voriconazole, but the combination of various antifungal agents may be required.

Bio-environmental factors associated with myopia: An updated review. / Los factores bioambientales asociados a la miopía: una revisión actualizada.

Experimental studies in animals, as well as observational and intervention studies in humans, seem to support the premise that the development of juvenile myopia is promoted by a combination of the effect of genetic and environmental factors, with a complex interaction between them. The very rapid increase in myopia rates in some parts of the world, such as Southeast Asia, supports a significant environmental effect. Several lines of evidence suggest that humans might respond to various external factors, such as increased activity in near vision, increased educational pressure, decreased exposure to sunlight outdoors, dietary changes (including increased intake of carbohydrates), as well as low light levels indoors. All these factors could be associated with a higher prevalence of myopia.

Retrobulbar chlorpromazine in management of painful eye in blind or low vision patients. / Clorpromazina retrobulbar en el manejo del ojo doloroso ciego o con baja visión.

OBJECTIVE: To evaluate the results of applying retrobulbar chlorpromazine in the management of patients with painful blind eyes or with very poor vision. METHODS: A retrospective, descriptive review was carried out on the medical records of 33 patients who were treated with a retrobulbar injection of chlorpromazine (25mg) for the management of painful blind eyes in Centro Oftalmológico Virgilio Galvis. RESULTS: Pain control was achieved in 90% of cases (with mean follow-up of 2.1 years). The mean intraocular pressure decreased by 37%. In 7 out of 12 eyes that maintained residual vision, loss of some degree of vision was acknowledged. One patient required an additional cyclodestructive procedure, another one required an absolute alcohol injection, and in an additional case evisceration surgery was necessary to achieve pain control. No serious complications were noted with this therapy. CONCLUSIONS: Retrobulbar injection of chlorpromazine is a valid option in painful, blind eye cases (or with very poor vision) with a poor visual prognosis.

UUnilateral corneal edema caused by a hidden foreign body. / Edema corneal unilateral causado por un cuerpo extraño oculto.

CASE REPORT: A middle-aged adult male was referred to our institution due to unilateral corneal edema for a possible corneal transplant. At first, the patient denied a history of trauma. A small foreign body, which had been overlooked by the primary ophthalmologist, was detected by gonioscopy, embedded in the anterior chamber angle. It was successfully surgically removed and visual results were good. DISCUSSION: In any patient with unilateral unexplained corneal edema, it is necessary to rule out the presence of a foreign body in the anterior chamber.

High-dose interleukin2 - a 10-year single-site experience in the treatment of metastatic renal cell carcinoma: careful selection of patients gives an excellent outcome.

BACKGROUND: VEGF-targeted therapy has become the mainstay of treatment for majority of mRCC patients. For most patients, benefit is short-lived and therefore treatment remains palliative in intent. HD IL2 is an effective immunotherapy treatment capable of durable remission in some patients but its unselected use has been difficult due to its modest response rate and considerable adverse effects. Using set pathology criteria as a selection tool in clinical practice, we have been able to show improved outcomes in our previous report. Here, we present an updated and extended report of this treatment and seek to explore any pathological, clinical and treatment variables likely to predict better outcomes. METHODS: This is an extension of a previously reported clinical audit, which includes mRCC cases treated with HD IL2 between 2003 and 2013. Since 2006, tumour specimens of potential candidates were routinely reviewed prospectively and stratified into Favourable or Other categories based on constitution of histological growth pattern, namely alveolar or solid versus papillary and/or sarcomatoid architecture; clear cell versus granular cell cytoplasmic morphology. HD IL2 was preferentially offered to patients with Favourable pathology. Outcome evaluation includes response rates, survival, and treatment tolerance. Multivariate analysis was performed to explore potential prognostic and predictive factors. RESULTS: Among prospectively selected patients with Favourable pathology (n = 106), overall response rate was 48.1 % (51/106) with CR rate of 21.6 % (23/106). Median OS was 58.1 months. Factors associated with significantly better response and/or survival includes favourable pathology pattern, higher cycle 1 tolerance and lower number of metastatic organ sites (<3). CAIX (Carbonic anhydrase 9) has prognostic value but is not predictive of response. Toxicities were those expected of IL2 but were manageable on general medical wards, with no treatment-related death. Importantly most complete responses were durable with 76 % (23/30) cases remained relapse-free (median 39 months follow up) and 2 of the seven who relapsed had had long-term disease free survival after resection of oligometastatic relapse. CONCLUSIONS: Our experience shows that HD IL2 remains an effective and safe treatment in well-selected cases of mRCC. The result in this single-institution patient series confirms similar outcomes to our previously reported retrospective series. Given the prospect of long-term remission, fit patients with Favourable histology and low disease burden should be considered for HD IL2 in an experienced centre. Better understanding has been gained from this in-depth analysis especially the examination of possible response predictors and strategies that can improve treatment outcome.

Keratoconus: an inflammatory disorder?

Keratoconus has been classically defined as a progressive, non-inflammatory condition, which produces a thinning and steepening of the cornea. Its pathophysiological mechanisms have been investigated for a long time. Both genetic and environmental factors have been associated with the disease. Recent studies have shown a significant role of proteolytic enzymes, cytokines, and free radicals; therefore, although keratoconus does not meet all the classic criteria for an inflammatory disease, the lack of inflammation has been questioned. The majority of studies in the tears of patients with keratoconus have found increased levels of interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α), and matrix metalloproteinase (MMP)-9. Eye rubbing, a proven risk factor for keratoconus, has been also shown recently to increase the tear levels of MMP-13, IL-6, and TNF-α. In the tear fluid of patients with ocular rosacea, IL-1α and MMP-9 have been reported to be significantly elevated, and cases of inferior corneal thinning, resembling keratoconus, have been reported. We performed a literature review of published biochemical changes in keratoconus that would support that this could be, at least in part, an inflammatory condition.

[In vitro antibiotic susceptibility to fluoroquinolones]. / Susceptibilidad antibiótica in vitro a fluoroquinolonas.

OBJECTIVE: To determine the antibiotic susceptibility of bacteria recovered from cultures of ocular infections in the Fundación Oftalmológica de Santander - Clínica Carlos Ardila Lulle (FOSCAL). MATERIALS AND METHODS: Retrospective descriptive study of a series of registries of cultures of samples from ocular surfaces and intraocular fluids from the OCULAB-FOSCAL laboratory in Floridablanca (Colombia) made between January and December of 2007. Antibiotic sensitivity screening by the method of Kirby-Bauer with impregnated Sensi-Discs™ of determined antibiotic concentrations was performed. RESULTS: A total of 352 samples were studied: 160 from conjunctiva, 150 from cornea and 42 from intraocular fluids. Of the total of the samples more than one microorganism was recovered 45.65% of the samples. Gram positive and Gram negative bacteria were identified in 78.7 and 18.4%, respectively. Resistance to gatifloxacin, moxifloxacin, ciprofloxacin and levofloxacin was observed in 6.3, 8.9, 33.2 and 35.6%, respectively, of Gram positive bacteria. Resistance to gatifloxacin, moxifloxacin, ciprofloxacin and levofloxacin was also observed in 7.4, 16.7, 16.7%and 25.9%, respectively, of Gram negative bacteria. The overall bacterial resistance (Gram positive and Gram negative) to moxifloxacin was 10.15%, and to gatifloxacin it was 6.46%, being which showed a statistically significant difference (P<.05). CONCLUSIONS: In our study the development of bacterial resistance to fourth generation fluoroquinolones was demonstrated in ocular samples. However, lower levels of resistance to fourth generation fluoroquinolones compared with that of third and second generation were found, particularly to Gram positive. Gatifloxacin showed lower resistance levels than moxifloxacin. Nevertheless, interpretation of this superiority must be made with caution in the clinical field, since other factors, like tissue penetration and in vivo activity, must be taken into account.

Evaluación del reimplante ureteral extravesical según la técnica de Lich-Gregoir en el tratamiento del reflujo vesico renal primario / Evaluation of extravesical ureteral reimplant using the Lich-Gregoir in the treatment of primary renal bladder reflux

Entre los años 1995 y 2003, fueron reimplantados un total de 490 unidades renales por técnica extravesical según Lich-Gregoir. Todos los casos correspondieron a pacientes pediátricos de ambos sexos portadores de reflujo vesico renal primario. Del total de unidades renales tratadas. 2 por ciento experimentaron persistencia del reflujo. El éxito global en el tratamiento de reflujo se logró en 480 unidades renales (98 por ciento). El porcentaje de hematuria macroscópica (4.08 por ciento) y disuria (2.71 por ciento) fue significativamente menor que el observado en las técnicas transvesicales (100 por ciento). El tiempo de estancia hospitalaria fue menos de 24 horas en 58 por ciento de los casos; entre 24 y 48 horas en 26 por ciento de los mismos, y sólo 16 por ciento de los infantes necesitaron 2 o mas días de hospitalización. Considerando los resultados, recomendamos la utilización de la técnica extravesical de Lich-Gregoir para el tratamiento del reflujo vesico renal primario de II, III y IV grado ya que ofrece menor morbilidad que las técnicas transvesicales.

[Corneal biomechanics]. / Biomecánica de la córnea.

OBJECTIVE: To review the corneal biomechanic concepts and to analyse, clarify and understand their relevance in refractive surgery. MATERIALS AND METHODS: A literature review has been done using different databases. RESULTS: Corneal biomechanic concepts are not new and are applied implicitly in numerous surgical procedures. Their origin is related to tonometry studies, but they gained in popularity when they were linked to the treatment of keratoconus, a pathology in which the mechanical properties of the cornea are altered. Factors determining corneal stability were thus defined. Corneal biomechanics have also been used following refractive surgery to study post-operative keratectasia and to improve ablation patterns, which ignores the corneal response. The new ablation systems need to include the biomechanical factors, which motivate research conducted in physical-mathematical models and in corneal wound healing, improving our knowledge about the corneal biomechanical response. CONCLUSIONS: The corneal biomechanic concepts have gained in popularity with the advent of refractive surgery, although they did exist previously. Their relevance is linked to improvements in the ablation systems used in an attempt to obtain more accurate and reliable results.

Vertebroplastia: um tratamento de fracturas vertebrais / Vertebroplasty: a treatment of vertebral fractures

La posibilidad de contar con una herramienta como es la vertebroplastia, para el tratamiento de las fracturas vertebrales por osteoporosis, en personas en quienes el tratamiento convencional no ha generado los resultados esperados, constituye una alternativa que, en las manos adecuadas y con la técnica indicada, se relaciona con mejoría del dolor. En la experiencia de los autores, en los procedimientos realizados hasta la fecha, se obtuvo mejoría significativa del dolor desde las dos primeras horas posteriores al procedimiento en el 70 por ciento de los pacientes