The lacrimal glands are the almond shaped glands (one for each eye) that give the eye the famous aqueous layer. The lacrimal glands produce tears that collect in the lacrimal sac and then drain through the lacrimal duct into the nose.
In modern days, eyelid and lacrimal disorders are very common. Minor disorders form a significant part of all the ophthalmology related treatments. But the forms of the disorders that cannot be treated by simple non surgical measures are usually referred to oculoplastic and lacrimal surgeons. The oculoplastic and lacrimal surgery training are a part of speciality training of ophthalmologists. While the general ophthalmologists take up only the less complex procedures, those surgeons who are trained in this dedicate and practice especially in this sub speciality.
What are the areas covered by the oculoplastic or lacrimal surgeon?
The surgery covers
- Correction of eyelid malpositions (inclusive of ptosis and lid retraction due to thyroid)
- Removal of tumour in the lids and surrounding tissues (and subsequent reconstruction of these tissues after tumour excision or trauma)
- Treating eyelashes that are in-growing
- Eye removal (no longer general enough to be performed by ophthalmologists) and prosthesis plantation for an artificial eye
- Secondary reconstructive procedures on the socket for an eye removed earlier
- Excessive watering in the eye
Dacryocystorhinostomy is a procedure for making a connection between the lacrimal sac and the lateral wall of the nose, by making an opening through the thin lacrimal bone that separates them. This may be done by a skin incision over the lacrimal sac or via the nose (Endoscopic DCR)
It aims to eliminate fluid and mucus retention within the lacrimal sac. It also increases tear drainage to relieve epiphora (water running down the face). The Dacryocystorhinostomy DCR focuses on the removal of bone adjacent to the nasolacrimal sac and then incorporating the lacrimal sac with the lateral nasal mucosa. This helps in bypassing the nasolacrimal duct obstruction (nasolacrimal duct obstruction (NLDO) can result in a watery eye, due to obstruction of the outflow of tears). This procedure allows tears to drain directly into the nasal cavity via a new low resistance pathway.
What are the symptoms?
- Mucopurulent discharge
- Blurred vision
- Bloody tears
- Crusting around the eyes in the morning
- Infection of the lacrimal sac in the inner corner of the eye
What are the problems treated with the dacryocystorhinostomy (DCR)?
Primary, acquired nasolacrimal duct obstruction, secondary acquired nasolacrimal duct obstruction, sinus inflammation, neoplasms, lacrimal pump weakness and after facial nerve palsy can undergo DCR. Anyone with the history of dacryocystitis or a failed congenital NLDO should be treated with DCR.
Types of DCR
The external DCR technique was originally described in 1904. The external dacryocystorhinostomy is a procedure where the larimal sac is directly operated upon. This has an increased success rate. A large osteotomy is created that can make the lacrimal sac abnormalities visible. The abnormalities include lacrimal stones, foreign bodies or tumours. This method uses direct suturing of the lacrimal sac and lateral nasal mucosal flaps that could be healed to create the bypass system. But this method can cause a visible scar in the eye region.
Endoscopic (endonasal) dacryocystorhinostomy
The endonasal approach was introduced in 1893 by Caldwell. In this method, an endoscope is inserted via the nasal passage and this allows the surgeon to see the abnormalities and treat them based on that. This method requires the surgeon to be proficient in the usage of endoscope or at least take the help of a ENT surgeon. There is no skin incision in this method and is much preferred for younger patients who do not have the skin creases that could camouflage a scar. Endoscopic DCR is effective as external DCR in recent times.
Less invasive, shorter operative time and preservation of pump function due to absence of external incision. There are no external scars and the complication is also lesser when compared to external DCR
Smaller opening between the lacrimal sac and nasal cavity, higher equipment cost, more learning required, and a lesser success rate than external DCR.
With the comparison of both the methods, the external DCR offers more exposure. While the endoscopic method has a good success rate, it is still not seen as the new standard in treatment. But with more practice and knowledge, the endoscopic DCR can become the new replacement to the external DCR.
Conjunctivodacryocystorhinostomy is a method in which a fistula is created between the medial commissural conjunctiva in to the nasal cavity. A Pyrex glass tube (Jones tube) is placed within the fistula to keep it functioning. This procedure completely bypasses the lacrimal drainage system.
A Conjunctivodacryocystorhinostomy (CDCR) is done when the abnormality is so severe that the reconstruction of a tear outflow apparatus cannot be done with the canalicular system. A Pyrex glass is used as a replacement to the skin and flap.
The Conjunctivodacryocystorhinostomy (CDCR) is also done in two methods – endoscopic and conventional. The endoscopic method has minimal postoperative edema, lesser surgical manipulation, no scarring, better placement and a more accurate length selection for the Pyrex tube. The assessment is also more accurate using en