in the lacrimal system typically 10Ð11 mm or 18Ð20 mm behind the punctum. In addition, membranous occlusions following a failed DCR can be treated successfully by laserdacryoplasty. Today, laserdacryoplasty is mostly performed in cases of canalicular stenosis and saccal stenosis. The mucosa of the lacrimal sac may not be acutely inßammated, with only a slightly enlarged diameter.

3.4.2 Contraindication for TLDP

Laserdacryoplasty is not useful in cases of acute dacryocystitis, mucoceles, or widespread adhesions following viral infections such as herpes or lacrimal stenosis caused by bone displacement after midface fractures.

3.4.3 Surgical Technique for TLDP

After a diagnostic endoscopy, the laser Þbre is brought into an endoscope with a third working channel and the laser is applied. After several laser impulses, free irrigation is noted. Irrigation is now possible without the former resistance and the endoscopic picture conÞrms the opening. After opening the obstruction, bicanalicular intubation using a silicone tube with a diameter of 0.64 mm is carried out to prevent postoperative adhesions of the mucosa. The tubing remains in place usually for 3 months and is removed transcanalicularly.

If there is no possibility of bicanalicular intubation, a monocanalicular stent is used according to Bernard and Fayet [24]. This Monoka intubation remains in place for at least 6 weeks. The post-operative therapy is the same as that following bicanalicular intubation, which is performed easily in the clinical setting, without general anaesthesia.

3.4.4 Results of TLDP

Using this method, the success rate of LDP related to the indicating symptom at epiphora is about 80% with a post-operative follow-up period of 20.4 months. As

regards canalicular stenosis alone, the success rate is 67% and rises to 86% for isolated common canaliculus stenosis [76]. These LDP results in the treatment of canalicular stenosis are better than those following other microsurgical procedures, even in the hands of experienced surgeons.

Emmerich et al. 1997 reported on 261 dacryoendoscopies following which DCR was performed in 70 patients, lacrimal intubation in 138 patients and laser dacryoplasty in 53 patients [21]. If the endoscopy showed a stenosis at the outlet of the lacrimal sac, punctiform canalicular stenosis or membranous restenosis after DCR, the stenosis was opened with an erbium:YAG laser. On account of the high absorption in the tissue (water) the thermic necrosis zone was only 10Ð20 mm. Tear duct stenting was performed for 3 months in all cases. After 3 months, 26 patients reported marked improvement, 12 slight improvement, 8 no change and 4 deterioration. Why 3 patients are missing is not mentioned. The paper by Meyer-RŸsenberg gives the same Þgures [53].

3.4.5Post-Operative Care and Complications of TLDP

Post-operatively we administer eye drops containing dexamethasone, polymyxin B and neomycin for 3 weeks and vasoconstrictive nose drops for 1 week.

In the case of dacryolithiasis and a concomitant infection with actinomyces or nocardia, we recommend eye drops with erythromycin and colistin for 6 weeks and erythromycin orally for 10 days.

3.5 Microdrill Dacryoplasty (MDP)

Immediately after the introduction of working transcanalicular dacryloplasty with the Erbium-YAG laser, Busse had the idea of introducing another tool into the third channel of the endoscope, namely, a miniaturised drill [20, 22].

The concept was to construct a microdrill for transcanalicular manipulation under endoscopic view. The microdrill consisted of a stainless steel probe 0.3 mm in diameter, driven by a battery-operated motor and a drill shaft. The frequency of the drill was 50 Hz. The