Since surgical incisions likely provide the entry site for infecting organisms, wound construction can play a role in the incidence of endophthalmitis. The intraocular concentration of organisms is highest at the time of surgery, after which it usually declines. If there is ingress of fluid from the ocular surface after cataract surgery, bacteria can be introduced at that time, increasing the likelihood of the development of endophthalmitis. An increased rate of post-cataract surgery infections has been reported during the last decade.¹,¹²,¹³ It has been proposed that the increased infection rates correspond to the increased use of clear corneal incisions for cataract surgery, because improperly constructed clear corneal cataract incisions are more prone to postoperative instability, leakage, and a potential influx of microbes than are sclerocorneal incisions.¹⁴
Few series found no greater likelihood of infection with corneal versus other types of incisions.¹⁵,¹⁶ Nevertheless, careful watertight incision construction and closure (with or without sutures) is mandatory, irrespective of surgical style, because the incidence of infection increases when there is a wound leak.¹³ Pediatric cataract surgeons tend to suture the wound more often than do adult cataract surgeons.

Surgical complications prolong the time spent in surgery and thus the exposure to potential infectious agents. Iris prolapse during the procedure, inadvertent rupture of the posterior capsule, and wound leaks are all potential complications that may increase the risk of postoperative endophthalmitis. Techniques that require multiple entries and exits of instruments into and from the eye may introduce more bacteria at the time of surgery. Any break in the posterior capsule that usually separates the anterior from the posterior chamber may lead to higher prevalence of endophthalmitis. In pediatric surgeries, the necessary removal of the posterior capsule in very young patients to prevent reopacification theoretically gives bacteria easier access to the vitreous cavity.

Immunodeficiency, active blepharitis, and lacrimal duct obstruction may increase the risk of infection. Good et al.⁴ noted the role of coexisting upper respiratory infection in postoperative endophthalmitis for children. The authors noted that upper respiratory infection is so common and repetitive in young children that their existence can be overlooked. All three cases reported by Good et al. received clearance for anesthesia from their pediatricians. Endophthalmitis is usually the result of introduction of bacteria into the eye at the time of surgery. However, Good et al.⁴ noted that they cannot exclude the possibility that the fitting of a contact lens in one of their case was the source of bacterial introduction, especially since infection occurred 5 days postoperatively, 2 days after contact lens fitting. Eyes with traumatic cataract and those receiving secondary intraocular lens (IOL) implantation may be at higher risk for developing infection. Although prevention of endophthalmitis is essential for every cataract surgery, eyes with traumatic cataract, reoperation (e.g., secondary IOL), and immediately sequential bilateral cataract surgery are especially more important to keep in mind. Eyes receiving immediately sequential bilateral cataract surgery require that surgeon treat both eye surgeries as completely separate procedures. Details are discussed in Chapter 9.

In addition to measures for hand disinfection, preoperative sterile preparation of the surgical site, and proper draping methods, the following measures have been reported.