Complex CNLDO: Buried Probe

Abstract

Buried probe is a variant of complex congenital nasolacrimal duct obstruction and is more commonly noted in older children [1–5]. This is an endoscopic diagnosis and is defined “as a condition when the entire nasolacrimal duct remains submucosally in the lateral wall of the nose up to the floor without any opening into the inferior meatus” [2]. It accounted for 10% of complex CNLDO’s [1]. The probe in these patients passes smoothly up to the floor without coming out in the inferior meatus. In such a case, the entire length of the probe movement in the lateral wall of the inferior meatus should be assessed to find out the thinnest mucosal point. This can be noted by the maximum light reflectance from the probe at the thinnest point. The probe is then gently tilted to come out from this point into the inferior meatus [2]. Routine intubation following buried probe exteriorization is not needed. Rarely, the probe may be covered by a thick nasal mucosa, and a 2–3 mm incision is given along the long axis of the NLD to exteriorize the probe followed by intubation. The outcomes are good with an anatomical success rate of around 90% [2]. This again emphasizes the fact that endoscopic guidance is mandatory for a good evaluation and management of CNLDO.