Incidence of interface fluid syndrome after laser in situ keratomileusis in Egyptian patients

Figures & data

Table 1 Preoperative characteristics of all patients

Preoperative characteristics	Total patients
Eyes (n)	3,489
Age (years)
Mean ± SD	27.4±5
Range	21 to 38
Sphere (D)
Mean ± SD	−4.5±1.3
Range	−2.00 to −7.00
Cylinder (D)
Mean ± SD	−1.43±0.8
Range	−1.00 to −4.00
IOP (mmHg)
Mean ± SD	15.2±1.2
Range	14 to 18
Central corneal thickness (μm)
Mean ± SD	549±25.6
Range	514 to 580

Abbreviations: SD, standard deviation; IOP, intraocular pressure.

Figure 1 Anterior segment optical coherence tomography of the interface fluid as optical space between the corneal flap and the stroma.

Figure 2 Corneal topography shows thickening of the cornea due to flap edema and interface fluid.

Abbreviations: Thk, thickness; Curv, curvature; Rbf, radial basic function; OS, occulus sinister [left eye].

Table 2 Postoperative characteristics of IFS group

Postoperative characteristics	IFS group
Eyes (n)	102
Age (years)
Mean ± SD	26.2±4.2
Range	23 to 34
Sphere (D)
Mean ± SD	−1.5±0.6
Range	−0.75 to −2.5
Cylinder (D)
Mean ± SD	−0.78±0.4
Range	−0.5 to −1.5
IOP (mmHg)
Mean ± SD	35±3.4
Range	28 to 43
Central corneal thickness (μm)
Mean ± SD	665±15.6
Range	580 to 689

Abbreviations: IFS, interface fluid syndrome; SD, standard deviation; IOP, intraocular pressure.

Table 3 Comparison between the preoperative characteristics of IFS group and control group (LASIK patients who did not develop IFS)

Preoperative characteristics	IFS group eyes, n (%) =102 (2.9)	Control group eyes, n (%) =3,387 (97.1)	P-value
Mean age (years) ± SD	26.2±4.2	26.6±5.2	0.44
Mean sphere (D) ± SD	−4.6±0.9	−4.4±1.1	0.07
Mean cylinder (D) ± SD	−1.2±0.4	−1.33±0.7	0.06
Mean IOP (mmHg) ± SD	15.3±2.1	15.1±1.3	0.13
Mean central corneal thickness (μm) ± SD	529±0.3	533±20.7	0.1

Abbreviations: IFS, interface fluid syndrome; LASIK, laser in situ keratomileusis; SD, standard deviation; IOP, intraocular pressure.