Evaluation Of The Effect Of Oral Isotretinoin On Meibomian Glands Using A Combination Of Non Contact Meibography And Lipid Layer Interferometry

Acne Vulgaris (AV) affects nearly  9.4 percent of the world population . Oral Isotretinoin used for  severe recalcitrant and nodulocystic acne reduces sebum secretion significantly as early as 6 weeks after initiation of treatment . Meibomian glands (MG) are analogous to  modified holocrine sebaceous glands;  hence isotretinoin may adversely affect the functioning of these glands . The purpose of this study was to evaluate in patients of acne vulgaris the effect of oral isotretinoin onMG structure and function using the Lipiview II (Tear Science Inc., Morrisville, N.C.)which  uses a combination of non contact meibography and  lipid layer interferometry to image the MG’s and to measure the lipid layer thickness(LLT) respectively.

This prospective, interventional, comparative study at a tertiary care institute included  25 patients and 21 age matched controls. Patients  included individuals with AV scheduled in the dermatology department to receive treatment with oral isotretinoin for 4 consecutive months  in 2 different doses: Group 1 (n=13)  : 0.5mg/kg/day  Group 2 (n=12) : 0.3 mg/kg/day.  Controls included patients planned for refractive surgery . One eye per subject was included using random number tables.

Inclusion criteria i) Patients with moderate nodular and severe papulopustular AV of Grade 3 severity (as defined by  European Dermatology Forum ) ii) Age > 12 years  and < 25 years Exclusion criteria:i) Ocular allergies ii) regular contact lens wear iii) cessation of isotretinoin treatment before 4 months iv) history of using topical or systemic immune modulators. All subjects underwent evaluation in the following sequence: i)SPEED score for dry eye symtoms ii) Lipiview imaging for MG morphology and  LLT   iii) dry eye evaluation - tear break up time (TBUT), Schirmer . Image J was ued to assess MG dropout in both lids . Dropout was assessed by calculating the ratio of MG area visualization/total lid area for both lids

Baseline clinical and meibograpy parameters were  comparable between controls and cases . TBUT , Schirmer 1 and LLT were comparable after 4 months of treatment with isotretinoin  in both groups 1 and 2 to baseline values  (all p’s > 0.05).The ratio of MG area to total lid area however decreased significantly for both groups after 4 months  e.g. In group 1 (0.5 mg/kg/day)  ratio of MG/ lid area decreased from 0.80 ± 0.11 to 0.65 ± 0.11 for the upper lid  (p=0.01) while in group 2 (0.3 mg/kg/day) this ratio decreased from 0.79 ± 0.06 to 0.71 ± 0.11 (p=0.02)  . Notable morphological changes in MG were present in majority of patients in both groups  including MG dropout, hooking , thinning, tadpoling, fading and presence of ghost glands