Evaluación de la estructura de las glándulas de meibomio mediante tecnología infrarroja

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Óptica y Optometría, Departamento de Optometría y Visión, leída el 26/06/2019Dry eye disease (DED) is a multifactorial disease of the ocular surface considered one of the most frequently encountered ocular conditions seen by eye care practitioners. Nowadays, DED is estimated to affect between 5 − 50% of the worldwide population. Furthermore, the prevalence of DED increases linearly with age which makes DED a growing public health concern as the global population of older people is expected to be more than double its current amount by 2050. According to DED classification, the aqueous deficient dry eye (ADDE) and evaporative dry eye (EDE) are the two major DED types and are considered to exist on a continuum rather than as separate entities. Despite this, according to the current DED understanding, an evaporative component is more common than an ADDE component. Currently, the Meibomian gland dysfunction (MGD) is considered the leading cause of EDE. This condition may result in alteration of the tear film, symptoms of eye irritation, clinically apparent inflammation and ocular surface disease. Therefore, any change that occurs in the morphology of the MG or in its secretion has an important clinical impact...El ojo seco o síndrome de ojo seco (SOS) es una enfermedad multifactorial de la superficie ocular considerada como una de las afecciones oculares más frecuentes observadas por los profesionales de la visión en la práctica clínica. Hoy en día, se estima que el SOS afecta al 5-50% de la población mundial. Además, su prevalencia aumenta linealmente con la edad, lo que hace que el SOS sea un problema de salud pública creciente, ya que se espera un aumento del doble de la población mundial de personas ancianas para 2050. Según la clasificación del SOS, se pueden distinguir principalmente dos tipos: el ojo seco acuodeficiente, caracterizado por un déficit en la capa acuosa de la película lagrimal y el ojo seco evaporativo, el cual se caracteriza por una alteración en la evaporación de esta. A pesar de esta diferenciación, recientemente se ha observado que ambos tipos de SOS pueden coexistir simultáneamente, aunque el componente evaporativo tiende a ser el más común. Actualmente, la disfunción de las glándulas de meibomio (DGM) se considera la causa principal de la SOS evaporativo. Esta condición puede provocar alteración de la película lagrimal, síntomas de irritación ocular, inflamación clínicamente aparente y enfermedad de la superficie ocular. Por lo tanto, cualquier cambio que se produzca en la morfología o en la secreción de las glándulas puede tener un impacto clínico importante...Zespół suchego oka (ZSO) jest wieloczynnikowym schorzeniem powierzchni ocznej i jedną z najczęściej obserwowanych w praktyce klinicznej dolegliwości okulistycznych. Obecnie szacuje się, że ZSO dotyka od 5 do 50% światowej populacji. Ponadto, zachorowalność na ZSO wzrasta liniowo z wiekiem. Szacuje się, iż populacja osób starszych ulegnie do 2050 roku podwojeniu, przez co ZSO może stać się znaczącym problem zdrowia publicznego. Zgodnie z przyjętą ogólnie klasyfikacją, podtyp ZSO związany z niedostatecznym wydzielaniem warstwy wodnej filmu łzowego (ang. aqueous deficient) oraz podtyp związany z nadmiernym jego parowaniem (ang. evaporative) są dwoma najbardziej powszechnymi rodzajami ZSO, które nierzadko są współistniejące. Badania naukowe pokazują, że ZSO spowodowane zwiększonym parowaniem łez występuje częściej niż pozostałe typy. Obecnie uważa się, że za ten podtyp odpowiada w dużej mierze dysfunkcja gruczołów Meiboma (ang. Meibomian gland dysfunction, MGD). Dysfunkcja ta powoduje zaburzenia filmu łzowego, podrażnienie, stan zapalny i chorobę powierzchni oka. Stąd też, każda zmiana zachodząca w morfologii gruczołów Meiboma lub w ich zdolności wydzielniczej ma duże znaczenie kliniczne...Fac. de Óptica y OptometríaTRUEunpu

Meibomian Gland Morphology: The Influence of Structural Variations on Gland Function and Ocular Surface Parameters

Purpose: To objectively and quantitatively characterize meibomian gland morphology and to investigate the influence of morphological variations on gland function and ocular surface and tear film parameters. Methods: One hundred fifty subjects were enrolled. The examinations included tear osmolarity, tear meniscus height, bulbar conjunctival hyperemia, noninvasive tear film breakup time, lid margin thickness, foam secretion, meibomian gland expressibility, count of functioning glands, corneal and conjunctival staining, fluorescein breakup time, lid wiper epitheliopathy, and Schirmer test. Patient symptoms were assessed using the Ocular Surface Disease Index questionnaire. Images from noncontact meibography were analyzed using an automated method that objectively estimates dropout area, number of glands, gland length and width, and gland irregularity. Results: Gland irregularity highly correlated with dropout area (r = −0.4, P < 0.001) and showed significant partial correlations with fluorescein breakup time (r = 0.162, P = 0.049) and the Ocular Surface Disease Index questionnaire (r = −0.250, P = 0.002) Subjects with dropout area <32% were divided into 2 groups: high and low irregularity. Gland expressibility was statistically significantly different between the 2 groups (U = 319.5, P = 0.006). In the high irregularity group, gland irregularity correlated with the Schirmer test (r = 0.530, P = 0.001) and corneal fluorescein staining (r = −0.377, P = 0.021). Conclusions: Automated morphological analysis of meibomian gland structure provides additional quantitative and objective information regarding gland morphology. The link between dropout area and gland function is not clear. Assessment of gland irregularity might better predict gland function and its effects on ocular surface and tear film parameters

The effect of ageing on the ocular surface parameters

Received 11 July 2017, Revised 18 September 2017, Accepted 19 September 2017, Available online 10 October 2017.Depto. de Optometría y VisiónFac. de Óptica y OptometríaTRUEinpres

A Novel Automated Approach for Infrared-Based Assessment of Meibomian Gland Morphology

Purpose: We present and validate a new methodology for analyzing, in an automated and objective fashion, infrared images of the meibomian glands (MG). Methods: The developed algorithm consists of three main steps: selection of the region of interest, detection of MG, and analysis of MG morphometric parameters and dropout area (DOA). Additionally, a new approach to quantify the irregularity of MG is introduced. We recruited 149 adults from a general population. Infrared meibography, using Keratograph 5M, was performed. Images were assessed and graded subjectively (Meiboscore) by two experienced clinicians and objectively with the proposed automated method. Results: The correlation of subjective DOA assessment between the two clinicians was poor and the average percentage of DOA estimated objectively for each Meiboscore group did not lie within their limits. The objective assessment showed lower variability of meibography grading than that obtained subjectively. Additionally, a new grading scale of MG DOA that reduces intraclass variation is proposed. Reported values of MG length and width were inversely proportional to the DOA. Gland irregularity was objectively quantified. Conclusions: The proposed automatic and objective method provides accurate estimates of the DOA as well as additional morphologic parameters that could add valuable information in MG dysfunction understanding and diagnosis. Translational Relevance: This approach highlights the shortcomings of currently used subjective methods, and provides the clinicians with an objective, quantitative and less variable alternative for assessing MG in a noninvasive and automated fashion. It provides a viable alternative to more time-consuming subjective methods

Nonsurgical Procedures for Keratoconus Management

Objectives. To describe the past 20 years’ correction modalities for keratoconus and their visual outcomes and possible complications. Methods. A review of the published literature related to the visual outcomes and possible complications in the context of keratoconus management using nonsurgical procedures for the last 20 years (glasses and contact lenses) was performed. Original articles that reported the outcome of any correction modalities of keratoconus management were reviewed. Results. The most nonsurgical procedure used on keratoconus management is the contact lens fitting. Soft contact lenses and soft toric contact lenses, rigid gas-permeable contact lenses, piggyback contact lens system, hybrid contact lenses, and scleral and corneoscleral contact lenses form the contemporary range of available lens types for keratoconus management with contact lenses. All of them try to restore the vision, improve the quality of life, and delay surgical procedures in patients with this disease. Complications are derived from the intolerance of using contact lens, and the use of each depends on keratoconus severity. Conclusions. In the context of nonsurgical procedures, the use of contact lenses for the management of keratoconic patients represents a good alternative to restore vision and improve the quality of live in this population

Comparison of Visual Performance and Patient Satisfaction Outcomes with Two Trifocal IOLs with Similar Optical Design but Different Materials

Purpose: To compare clinical outcomes in a prospective trial of cataract surgery patients bilaterally implanted with two different trifocal intraocular lenses (IOLs) with very similar optical designs but consisting of different IOL materials (hydrophobic and hydrophilic). Patients and Methods: Fifty-one patients (102 eyes) were randomized to receive trifocal IOLs bilaterally – FineVision POD F (hydrophilic) or FineVision POD F GF (hydrophobic) (both PhysIOL, Liége, Belgium). The follow-up period was 3 months. Outcome measurements included uncorrected distance (UDVA), corrected distance (CDVA), distance-corrected intermediate (DCIVA), and distance-corrected near visual acuity (DCNVA), refraction, negative dysphotopsia, optical quality of vision, contrast sensitivity under photopic and mesopic conditions, halometry (discrimination index), and patient-reported outcomes. Results: At the final study visit, mean (SD) values for binocular UDVA, CDVA, DCIVA (80 cm), and DCNVA (40 cm) were − 0.01 (0.06), − 0.04 (0.04), 0.09 (0.10), and 0.10 (0.09) logMAR, respectively, for POD F, and 0.01 (0.08), − 0.03 (0.03), 0.08 (0.1), and 0.13 (0.11) respectively, for POD F GF. Defocus assessments showed a continuous curve with a functional range of visual acuity (≤ 0.15 logMAR) from ∼ 30 cm to infinity in both groups. The discrimination index was > 0.85 for all patients, and both groups showed similar contrast sensitivity under photopic and mesopic conditions. At 3 months, no patient reported negative dysphotopsia, and high satisfaction rates were observed. Conclusion: Clinical outcomes showed no significant difference between each lens when measured at 1 month and 3 months after implantation. This equally good clinical performance of hydrophilic and hydrophobic trifocal lenses allows the surgeon to choose the IOL material based on personal preferences or patients’ needs

The influence of meibomian gland loss on ocular surface clinical parameters

Purpose: To assess the relationship between the meibomian gland loss (MGL) and relevant ocular surface clinical parameters as well as the influence of age in this relationship. Methods: A total of 161 participants (mean age; 42±17 years) were enrolled in this study. Infrared meibography was performed using Keratograph 5M (K5M; Oculus GmbH, Wetzlar). Participants were divided into five groups according to total meiboscore and the ocular surface parameters of each MGL group were studied. In addition, the relationship between MGL and the ocular surface parameters was established including age as covariant. Results: Both eyelids were taken into account since no association between the MGL from upper and lower eyelid was found (k value=0.2; p=0.3) despite they were significantly correlated (r= 0.3; p<0.001). No statistically significant differences were found in symptomatology among different MGL groups. Statistically significant differences were found among MGL groups in tear osmolarity (p=0.02), bulbar redness (p=0.04), corneal and conjunctival staining (p=0.01 and p=0.004, respectively). Despite this, only corneal staining showed a significant correlation with MGL when age was covariant (r=0.2; p=0.04). Conclusions: MGL higher than 50% seems to be accompanied by signs on the ocular surface. Furthermore, age demonstrated to be a relevant factor when assessing MGL. For this reason, future studies should compare age-matched groups in order to know the contribution of the MGL on the ocular surface and establish valid cut-off values for dry eye diagnosis

Randomized crossover trial of silicone hydrogel contact lenses

Purpose: The aim of the current study is to assess, using new technologies, the interaction of four monthly silicone hydrogel contact lenses on the ocular surface and the comfort over 15 days of use. Methods: Prospective cross-over, randomized and double-masked study including four materials (lotrafilcon-B, samfilcon-A , comfilcon-A and filcom-V3). Clinical examination was performed in the following order: tear meniscus height, first break-up of the tear film, the average time of all tear film breakup incidents, bulbar redness, limbal redness (Keratograph 5M ,Oculus, Germany); central corneal thickness (Pentacam, Oculus, Germany), thermography values (FLIR A325; FLIR Systems Inc., USA), and slit-lamp evaluations, including ocular surface staining. Finally, subjective comfort was obtained from Contact Lens Dry Eye Questionnaire-8. Results: The impact of contact lens wear on the ocular surface didn’t show statistically significant changes over time except for corneal and conjunctival staining grades on day 15 compared to day 1 for the comfilcon A group (P = .003 and P = .01, respectively). Contact lens stability and impact on the ocular surface during contact lens wear didn’t show statistically significant changes over time except in the case of the comfilcon A material with respect to the irritation item (P = .01). Conclusions: These results suggest that the impact of monthly silicone hydrogel contact lens materials on the ocular surface after and during contact lens wear, contact lens stability over time, and subjective comfort did not reveal any significant changes over 15 days of use for any of the materials

Repeatability of Noninvasive Keratograph 5M Measurements Associated With Contact Lens Wear

Objetive: To assess the intrarater repeatability of the measurements of tear meniscus height (TMH), noninvasive keratograph tear break-up time (NIKBUTs), and ocular redness measurements obtained with the Keratograph 5M (K5M) in a sample of soft silicone hydrogel contact lens (CL) wearers over 15 days. Methods: Prospective study over two consecutive weeks. Three measurements of TMH, NIKBUTs (NIKBUT first and NIKBUT average), and ocular redness were obtained in different sessions; the first day (baseline, at 8 hr of wear, and after lens removal) and the last day of wear-15th day (at 8 hr of wear and after lens removal). The repeatability of measurements were assessed by two intraclass correlation coefficient (ICC) forms; single measurement [ICC (2,1)] and multiple measurements (k=3) [ICC (2, k)]. Results: Sixty-four eyes were analyzed. The repeatability of baseline TMH [ICC (2,1) greater than 0.90; coefficient of repeatability (CR)=0.06 mm] and after and during CL wear [ICC (2,k) greater than 0.90; CR≤0.07 mm] were excellent. The repeatability of baseline NIKBUT average [ICC (2,k)=0.89 (0.82-0.93); CR=6.07 sec] was maintained after CL removal but was poorer during CL wear. The repeatability of baseline NIKBUT first [ICC (2,k) =0.80 (0.69-0.87); CR=8.74 sec] was maintained after CL removal and during CL wear at moderate-good level. Conclusions: Intrarater repeatability of TMH, NIKBUTs, and ocular redness performed by K5M after CL wear remains stable when three measurements are performed. However, intrarater repeatability during CL wear decreased only for NIKBUT average and was not affected by time of use (15 days)