Preoperative preparation includes decongestion of the inferior meatus with 0.05 % Oxymetazoline. Two drops can be placed half an hour before the procedure or alternatively a cottonoid soaked with the drug can be placed in inferior meatus for 5 min before the procedure. Following dilatation of the puncta, a probing is performed as a standard procedure and the probe is inspected in the inferior meatus to confirm that all the blocks are overcome. An I-probe (Quest Medical Inc, Allen, Texas, USA) can be used which is similar to a bowman’s probe with a small eyelet near the tip to wash off the debris following probing and also to reflect on the free flow following probing (Fig. 17.3c). Inferior turbinate medialization may occasionally be needed along with probing if it appears to be impacted to the lateral wall.

The sleeve of the balloon is removed, it is then lubricated with either a viscoelastic or a 1 % carboxymethycellulose drops and gently placed into the lacrimal system just like the procedure of probing and introduced further into the nasolacrimal duct till the 15 mm mark is adjoining the puncta (Fig. 17.3d) or the balloon exits just beyond the valve of Hasner as seen with nasal endoscopy. In the meantime the inflation device filled with saline or fluorescent-stained saline (Fig. 17.4a) should be ready in the locked position (Fig. 17.4b). The air should be removed from the device after saline filling. The luer-lock hub of the inflation device is connected to the catheter (Fig. 17.4c) and the knob is slowly rotated in the clockwise direction (Fig. 17.4d) by the assistant while the surgeon can be visualizing the dilatation of the balloon via the endoscope.

The balloons are inflated to 8 atm of pressure for a duration of 90 s (Fig. 17.5a). The inflated balloon should be under constant monitoring in the nose (Fig. 17.5b). The knob of the inflation device is then rotated in an anti-clockwise manner to deflate the balloon. Once deflated, without disturbing the catheters position, it is reinflated to 8 atm for 60 s. The balloon is again deflated (Fig. 17.5c) and pulled back till the 10 mm mark adjoins the punctum or the tip of the balloon is barely visible proximal to valve of Hasner (Fig. 17.5c). The two cycles of inflation and deflation are carried out again in this position. The catheter and the inflation device are then disconnected followed by gentle withdrawal of the catheter from the lacrimal system. The lacrimal passages are then irrigated with either saline or fluorescein-stained saline (Fig. 17.6a). The fluid should flow easily and in copious amounts indicating success of the procedure. The saline from the inflation device is then emptied after unlocking the device (Fig. 17.6b).