TAMING POSITIVE PRESSURE: CANTHOTOMY–PPV–PHACO–TRABECULECTOMY FOR AAC

To illustrate surgical planning and intraoperative strategies for cataract extraction in a nanophthalmic eye presenting after acute angle-closure crisis when standard preoperative biometry is unobtainable, emphasizing the role of UBM and expectations for postoperative management.

Tertiary anterior-segment/glaucoma service.

A 56-year-old East Asian Brazilian woman presented one week after an acute angle-closure crisis with a small, nanophthalmic eye and marked corneal edema. Over 3–4 days, serial decompressive paracenteses were performed in an attempt to obtain preoperative measurements; biometry remained infeasible. Ultrasound biomicroscopy (UBM) confirmed an extremely shallow anterior chamber and crowded anterior segment, guiding surgical planning. In the operating room, intravenous mannitol was administered, followed by lateral canthotomy to mitigate positive pressure, pars plana vitrectomy to deepen the anterior chamber, trabeculectomy, and phacoemulsification with IOL implantation. IOL power selection was constrained by the absence of keratometry/axial data; a best-estimate approach was used with appropriate counseling regarding refractive uncertainty. During the first postoperative week, pronounced anterior capsular contraction occurred, requiring Nd:YAG anterior capsulotomy. At final follow-up, the patient achieved 20/20 distance acuity and J1 near.

In nanophthalmic eyes with recent acute angle closure and edematous corneas, UBM is pivotal for anatomic mapping when biometry is impossible. A pressure-control and chamber-deepening sequence—mannitol, canthotomy, posterior vitrectomy—can facilitate safe phaco and concomitant trabeculectomy. Surgeons should anticipate IOL power uncertainty, proactively monitor for early capsular phimosis, and intervene with Nd:YAG when indicated. The structured approach enabled anatomical recovery and excellent visual outcomes despite extreme preoperative constraints.