This was a retrospective review of 589 consecutive cases of patients who underwent 23-gauge tranconjunctival pars plana vitrectomy. Cases were split into Type 1 vitrectomies (macular hole, ERM and simple vitreous haemorrhages) and Type 2 cases which were more complex requiring more extensive instrument use and torqueing of the globe (e.g. Rhegmatogenous retinal detachment and proliferative diabetic retinopathy with tractional retinal detachment). Clinical and surgical factors were analysed to determine their effects on suturing rates. Overall 227 (38.5%) required at least one sclerotomy suture at the end of surgery. Sixty-nine had one sutured sclerotomy, 52 had two sutured sclerotomies and 106 had three sutured sclerotomies. Surgical technique, tamponade agent and vitrectomy type had significant effects on the incidence of intraoperative suturing. A high suturing rate was observed in cases where no gas tamponade was used and also in Type 2 vitrectomy cases. The overall hypotony rate was 2.2% with a non-statistically significant difference between fluid filled and gas filled eyes. Surgeon experience did not have a significant association with suture rates. Surgical technique was the most significant risk factor for sclerotomy suturing. Differences in particular surgical steps, such as the angle of entry of the trocar, how the cannula is removed, the duration of compression of the sclerotomy site after cannula removal, the IOP at the end of the case, and tolerance for sclerotomy leakage, are all surgeon dependent and certainly affected suturing rates. The authors explain that the Type 2 cases may have had sclerotomies stretched open for longer durations, and more torque on the sclerostomies due to instrument manipulation. They also suggest that more extensive vitreous base dissection reduces the amount of ‘vitreous plugging’, which may aid in sealing the sclerotomy. They comment that careful assessment of the sclerotomy sites at the end of surgery is encouraged in all cases, especially in eyes with these risk factors.