Comparison Of Large Air Bubble And Lamellar Surgical Techniques In Deep Anterior Lamellar Keratoplasty

Currently, Deep Anterior Lamellar Keratoplasty (DALK) has become one of the commonly used surgical options for eyes with pathologies such as keratoconus (KC), corneal scars, dystrophic corneal disorders, and degenerations. One of the greatest advantages of DALK surgery is that it provides superiority over Penetrating Keratoplasty (PK) and minimizes complication risks by selectively removing the pathological stroma while preserving the patient’s own endothelium. While eliminating complications such as endothelial rejection, visual rehabilitation occurs earlier compared to PK. During DALK surgery, air injected into the corneal stroma can result in three different types of big bubbles (BB).

Since Type2 BB and Mixed Type BB are more prone to perforations. Building upon this idea, we investigated the relationship between Big Bubble (BB) and Lamellar dissection techniques in DALK surgery in our clinic, focusing on indications and the development of postoperative double anterior chamber (DAC).

Between May 2011 and June 2023, a retrospective study was conducted on 87 male and 75 female patients (162 eyes) who underwent DALK surgery and were followed for at least 3 months. The indications, intraoperative Descemet membrane rupture, DAC development, changes in postoperative visual acuity, and the need for additional surgical interventions were statistically investigated by performed using SPSS 23.0 software.

In 74.7% cases, DALK was performed using the BB (86 type 1, 21 type 2,14 mixed) and 25.3% using lamellar dissection technique. In keratoconus cases, Type 1 BB was most commonly observed during surgery, while in dystrophy cases,Type2 BB was more frequent (p=0.024).In 35 cases (21.6%), intraoperative Descemet membrane rupture occurred, and in 38 cases (23.5%), postoperative DAC developed, with intracameral air and gas injection performed as treatment. The development of DAC was more commonly observed in the BB group (78.4%) The frequency of intracameral air injection did not show a significant difference according to the diagnosis groups (p=0.329),but in terms of surgical techniques, it was significantly higher in Type 2 BB (57.1%) (p=0.001).

In all cases, visual acuity improved in the postoperative period, and no significant difference was observed according to the diagnosis and surgical methods. In DALK surgery, the frequency of BB formation did not show a significant difference according to the diagnosis groups. The frequency of intracameral air injection for postoperative DAC did not show a significant difference based on the diagnosis groups, but based on surgical types, it was most frequently required in Type 2 air bubbles. According to the type of surgery, since Type 2 BB is more commonly observed, leaving air in the anterior chamber at the end of the operation in these cases may be effective in preventing the development of DAC.