Abstract
Purpose: :
25G Gauge Vitrectomy is today widely used in order to accelerate patient recovery after surgery: this technique is supposed to preserve ocular surface integrity resulting in reduced postoperative ocular discomfort. The aim of this study was to determine the presence of syntoms and signs of ocular surface dryness in patients treated with Vitrectomy 20G (group A) and Vitrectomy 25G (group B) and to compare the results between the two study groups.
Methods: :
We studied 16 patients (16 eyes; mean age: 68±10 years). 9 eyes underwent 25G vitrectomy and 7 eyes 20G vitrectomy. Each patient unswered a dry eye questionnaire and underwent a complete ocular examination. Clinical measurements of tear function (BUT, Schirmer 1) were completed and ocular surface osmolarity was quantified. Corneal surface integrity was determined by means of fluorescein staining. Patients were evaluated before surgery and 7 days after surgery. Individuals with ocular surface diseases, contact lens or ocular drug users were excluded.
Results: :
No symptoms and signs of ocular surface disease were detected before surgery in all patients. A significant increase in mean corneal fluorescein staining score was observed in group A if compared to group B at day 7 after surgery (P<.001). At this time point corneal fluorescein staining was detected in all group A eyes and the pattern of fluorescein staining was either diffuse (57.1%) or punctate (42.9%). At day 7 BUT score was lower than 5 sec in 50% group A eyes and in 22.3% group B eyes. Non-statistically signficant difference in Schirmer test values and Osmolarity was found between the two groups. All group A patients reported dry eye symptoms and only 12% group B patients at day 7.
Conclusions: :
Our results indicate that tear film and ocular surface are less affected after small gauge Vitrectomy, if compared to traditional 20G. In 20G Vitrectomy conjunctival dissection may alterate limbal basal and stem cells turnover leading to diffuse corneal epithelial defects. By preserving ocular surface integrity, 25G Vitrectomy significantly reduces corneal epithelial damage and ocular surface discomfort.
Keywords: vitreoretinal surgery • cornea: tears/tear film/dry eye • cornea: epithelium