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Objective: Demodex folliculorum blepharitis is typically confirmed with lash epilation and microscopic identification of mites. However, mite counts may vary with the epilation technique. As there is no gold standard to epilating lashes for the purposes of mite counts, the aim of this study was to compare three epilation techniques., Method: A prospective randomized double-blind study compared three epilation techniques on lashes with cylindrical dandruff. Techniques included (A) direct pulling of the lash; (B) rotating the lash before epilation; and (C) sliding the cylindrical dandruff away, lash rotation, and epilation. Mean mite counts were analyzed using a repeated-measures analysis of variance., Results: Forty (n=40) participants (20 M: 20 F, mean age of 62.3±17.1 years) revealed similar mite counts between right (1.43±1.74) and left (1.35±1.59) eyes ( P =0.63). A significant difference ( P =0.03) in mite count was noted (technique A: 1.05 ± 1.60; technique B 1.76 ± 1.80; and technique C 1.36 ± 1.54) with technique B yielding the highest mite count ( P =0.04)., Conclusion: Demodex mite count is a key parameter in establishing infestation or to determine treatment efficacy. This study revealed that rotating the lash before epilation yielded the highest mite count. Future studies should report the epilation technique used to allow for study comparisons., Competing Interests: E. Bitton has received funding/honoraria in the past from Aequus Pharmaceuticals, Alcon, American Academy of Optometry, British Contact Lens Association, Canadian Dry Eye Summit, Canadian Optometric Education Trust Fund (COETF), Johnson & Johnson, Inc., Labtician, Labtician-Théa, Novartis, Santen, and Sun Pharma. The remaining author has no funding or conflicts of interest to disclose., (Copyright © 2024 Contact Lens Association of Ophthalmologists.)

Demodex is the most common parasite living on humans and yet little is understood about its pathogenicity with respect to the ocular surface. An increasing interest in Demodex over the past 20-years has increased our understanding of this mite and its pathogenetic role. This article begins with a review of the anatomy, life cycle, mode of transmission and advances in genetics that can distinguish between Demodex folliculorum and Demodex brevis, the only two Demodex species in humans. Additionally, a review of diagnostic procedures and existing and emerging ocular and systemic management options are presented. Despite the increasing interest in Demodex in the literature, there remains numerous obstacles for future studies, hence a section of this review is dedicated to the identification and proposal for future considerations. The lack of uniformity with respect to terminology, diagnostic technique and management approach for Demodex remain as obstacles for future study comparisons. This review summarised the current knowledge on Demodex and hopes to offer some recommendations for future directions in the study of Demodex in humans.

Purpose: To evaluate facial Demodex densities in participants with varying severities of blepharitis secondary to Demodex folliculorum assessed by the highest number of cylindrical dandruff on one lid., Methods: This double masked cross-sectional study included 58 participants [19 control, 21 mild/moderate and 18 severe Demodex blepharitis] who underwent a standardized skin-surface biopsy and a lash epilation for each lid to obtain the forehead Demodex densities and the overall lash mite count, respectively. Also, facial photographs were taken to evaluate facial erythema and dermatological conditions. The Ocular Surface Disease Index [OSDI], non-invasive break-up time [NIBUT], tear meniscus height [TMH], bulbar conjunctival redness as well as additional questions on watery eyes, ocular itching and itching along the lids were assessed., Results: Both mild/moderate and severe Demodex blepharitis groups were over the cut-off value [≥ 5 mites/cm 2 ] that confirms a facial demodicosis (mild/moderate: 5 ± 1; severe: 6 ± 1) while the control group was below it (2 ± 1). Thereby, group comparisons showed that an increased severity of Demodex blepharitis was associated with higher forehead mite densities (p = 0.002) and increased lash mite count (p < 0.001). The degree of facial erythema was also positively correlated with forehead mite densities (rs = 0.31, p = 0.02). When compared to the controls, the mild/moderate group had more watery eyes (X 2  = 6.54, p = 0.02), a lower TMH (U = 100.5, p = 0.006) and the severe group had more itching along the lids (X 2 = 4.94, p = 0.04). The other ocular signs and symptoms [NIBUT, bulbar conjunctival redness, OSDI] were not affected by the severity of Demodex blepharitis (p > 0.05)., Conclusion: Palpebral and facial Demodex infestation can co-exist, as the presence of blepharitis secondary to Demodex is associated with increased facial mite densities., Competing Interests: Declaration of Competing Interest SA has received honorarium for conferences/consulting from Allergan and Shire. EB has received funding from Alcon, Allergan, Canadian Optometric Trust Fund, I-Med Pharma Inc, Shire and honorarium for conferences/consulting from Akorn, Alcon, Allergan, American Academy of Optometry, Canadian Association of Optometry, CooperVision, Labtician, Jobson Publishing, Novartis, Santen, Shire., (Copyright © 2019 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)