Purpose: To evaluate the healing of scleral incisions (sclerotomies) of 23-gaugetransconjunctival sutureless vitrectomy (TSV) by single- and two-step techniquesusing ultrasound biomicroscopy (UBM) images.Patients & Methods: In this prospective study, twenty consecutive eyes (20patients) were submitted to 23-gauge TSV surgery divided in 2 groups: (1) usinga beveled trocar to insert the microcannula (one-step technique) and (2) using amicrovitreoretinal (MVR) blade to perform first a tunnel incision and then insertthe microcannula (two-step technique). UBM examination was performed 7 – 14days postoperatively to locate and document the sclerotomy sites.Results: Mean Postoperative time for UBM examination was 9.1 ± 2.53 days(range: 7– 14 days). UBM imaging of 20 eyes (20x3 sclerotomies) showed thatcomplete healing was found in sclerotomies in two-step and insclerotomies in one-step techniques (90% and 96.67% respectively), partial woundhealing in sclerotomy (3.33%) in one-step, and gapping of the internalwound lips which not affect the end result of surgery or threaten the vision wasfound in sclerotomies (10%) in two-step. There was neither vitreousincarceration nor fibrovascular ingrowth (FVIG). Mean microcannula entrancetime was 82.4 ± 11.66 sec (range: 64 – 99 sec) in two-step group and 44.8 ± 5.22sec (range: 36 – 52 sec) in one-step group (P = .517), while mean microcannulaexit time was 36.7 ± 7.47 sec (range: 24 – 47 sec) in two-step group and 28.3 ±4.81 sec (range: 23 – 36 sec) in one-step group (P = .274). No case of ocularhypotony or endophthalmitis was observed at the end of follow-up time.Conclusion: Healing of 23-gauge sclerotomy sites is quite rapid, proper, andcomplete with perfect apposition of the internal wound lips and inability to detectthe site of sclerotomy in a short duration of 2 weeks postoperatively as shown byUBM examination. There is no statistical significant difference between the twogroups in the time of entrance and removal of microcannulae.