1. NON PENETRATING DEEP SCLERECTOMY AND TRABECULOTOMY FOR GLAUCOMA
Arturo Maldonado-Bas, MD, PhD Arturo Maldonado-Junyent, MD
Financial Disclosure
We do not have any financial interests or
relationships to disclose.
CLÍNICA DE OJOS MALDONADO BAS
CORDOBA - ARGENTINA

2. Introduction Material and Methods
Trabeculectomy, which has been the glaucoma surgery gold standard till now, is beginning to be replaced in many cases by non penetrating deep sclerectomy (NPDS) because this has fewer complications. Nevertheless, NPDS seems to provide less IOP control over time. Intrasurgical absorbable devices are now being employed to maintain postsurgical filtration.
Trabeculotomy, on the other hand, has also been used to treat congenital glaucoma provoked by mesodermal remains in the angle.
The purpose of this study is to evaluate the efficacy and safety of IOP control using a combined technique of NPDS with trabeculotomy.
Material and Methods
Between August 2005 and March 2009, 61 eyes were operated, presenting open-angle glaucoma without intraocular pressure control with maximum medication.
- 33 eyes underwent NPDS with trabeculotomy (Group I).
28 eyes underwent NPDS with trabeculotomy combined with phacoemulsification
and intraocular lens implant (Group II).
Intraocular pressure equal to or less than 16 mmHg with or without medication was considered a success. 

3. Material and Methods The data of the whole group of 61 eyes:
Average age was 68 years, with a range between 48 and 86. Sex distribution was 22 men and 39 women. Average pre-surgical intraocular pressure was mmHg, with standard deviation and a range between 14 and 45 mmHg. Average follow-up was months with a range between 4 and 43 months. No antimetabolites, viscoelastics or devices were employed to improve the results.
The data of group I:
Average age was 66 years, with a range between 48 and 82. Sex distribution was 13 men and 20 women. Average pre-surgical intraocular pressure was mmHg, with standard deviation and a range between 14 and 30 mmHg. Average follow-up was months with a range between 4 and 43 months. 
The data of group II: 
Average was 71 years, with a range between 57 and 86. Sex distribution was 9 men and 19 women. Average pre-surgical intraocular pressure was mmHg, with standard deviation and a range between 14 and 45 mmHg. Average follow-up was months with a range between 4.9 and 42 months.

4. Fig. 2: Yuxtacanalicular extraction
Surgical technique: 
1. Subtenonian anesthesia: Lidocaine at 2% without epinephrine.
2. Alvarado traction stitch with 7-0 silk.
3. Fornix based conjunctival dissection.
4. A 4-3 mm scleral flap, 300 microns thick.
5. Paracenthesis with or without phacoemulsification according to the case.
6. Deep scleral flap dissection unroofing the Schlemm canal and exposing the Descemet membrane. Sclera must be dissected up to the deepest layers also to obtain uveal filtration (fig. 1).
7. Juxtacanalicular extraction by means of forceps (fig. 2).
8. Trabeculotomy to both sides with the Sourdille trabeculotome up to the scleral flap without invading the NPDS area (Fig. 3).
9. Scleral suture with two to four 9-0 nylon stitches (these may be removable).
10. 7 or 8-0 silk conjunctival flap suture.
Fig. 1: Deep Scleral flap.
Fig. 2: Yuxtacanalicular extraction
Fig. 3: Trabeculotomy.

5. Results Analyzing the groups separately:
In the total group of 61 eyes: 
Average post-surgical IOP at 2 years was 12.25, standard deviation +/-1.06 with a range beween 10 and 14 mmHg. The average of the latest IOP of each patient was mmHg, standard deviation +/-4.31 with a range between 9 and 40 mmHg. Average success was 88.52% (54 eyes). Intraocular pressure was controlled in 47 eyes (87.03%) without medication and in 7 eyes (12.97%) with medication. The failure rate was 11.47%, i.e. 7 eyes. The difference between pre- and post-surgical measurements was 8.96 mmHg. 35 cases had hyphema between 1 to 12 days post-surgery, resolved without consequences.
7 cases (11.47%) required yag laser goniopuncture to maintain postsurgical filtration.
Analyzing the groups separately:
Group I:
The average postsurgical IOP at 2 years was mmHg with a standard deviation of 1.17 and a range between 10 and 13 mmHg. The average of the latest IOP of each patient was 13 mmHg, standard deviation +/-5.36 with a range between 9 and 40 mmHg. Average success was 84.84% (28 eyes). Intraocular pressure was controlled in 23 eyes (82.14%) without medication and in 5 eyes (17.85%) with medication. The failure rate was 15.15%, i.e. 5 eyes (in one of which IOP was controlled for 18 months below 13 mmHg without medication until cataract surgery was performed with phacoemulsification and intraocular lens implant, at which time the bleb stopped functioning and 2 trabeculectomies had to be performed in order to regulate the IOP again). The difference between pre- and post-surgical measurements was 8.30 mmHg. 

6. Results 
Group II:
Average postsurgical IOP at 2 years was mmHg with a standard deviation of 0.82 and a range between 12 and 14 mmHg. The average latest IOP of each patient was mmHg, standard deviation +/-2.65 with a range between 9 and 23 mmHg. Average success was 92.54% (26 eyes). Intraocular pressure was controlled in 24 eyes (92.30%) without medication and in 2 eyes (7.69%) with medication. The failure rate was 7.14%, i.e. 2 eyes. The difference between pre- and post-surgical measurements was 9.75 mmHg. 6

7. Conclusions 
According to the results of this study it can be concluded that NPDS combined with trabeculotomy is a good surgical procedure to reduce IOP.
It can also be concluded that the association of this technique with phacoemulsification and IOL implant improves the success rate.
References 
1. Shaarawy T, Nguyen C, Schnyder C, Mermoud A. Comparative study between deep sclerectomy with and without collagen implant: long term follow up. Br J. Ophthalmol. 2004 ;88 ;95-98.
2. Paufique L et al (1970). Technique et résultats de la trabeculotomie ab externo dans le traitement du glaucoma congénital. Bull et M de la Soc Franc d´Ophtalmol. Masson et Cie Editeurs, París:
3. Harms H & Dannheim R (1970): Epicritical consideration of 300 cases of trabeculotomy “ab externo” Trans Ophtalmol Soc UK 89:
4. Sampaolesi, R. Glaucoma, Ed. Médica Panamericana, Buenos Aires 1991;
5. Gimbel, H. et al. Intraocular pressure response to combined phacoemulsification and trabeculotomy ab externo versus phacoemulsification alone in primary open-angle glaucoma. J Cataract Refract Surg – 1995; 21:
6. Fyodorv SN et al (1984): Deep sclerectomy: technique and mechanism of a new glaucomatous procedure. Glaucoma 6:
7. Zimmermann TJ, et al. Effectiveness of non penetrating trabeculectomy in aphakic patients with glaucoma. Ophthalmic Surg 1984;15:44-50.
8. D ly P, Jeanteur-Lunel MN, et al (1996): Non-penetrating deep sclerectomy associated with collagen device in primary open angle glaucoma: middle-term retrospective study. J Fr Ophtalmol 19:
9. Kozlov VI & Kozlova TV (1996): Non-penetrating deep sclerectomy with collagen drainage implantation (ABSTRACT 9-02). 5th Congress and the Glaucoma Course of the European Glaucoma Society, June 1996, Paris. Abstract Book: 120.
10. Sourdille, P., Santiago, P., et al: Reticulated hyaluronic acid implant in non-perforating trabecular surgery. J Cataract Refract Surg 1999; 25:
11. Mermoud, A., et al: Yag goniopuncture after deep sclerectomy with collagen implant. Ophthalmic Surg and Lasers 1999;30:2,
12. Arenas archila E. Trabeculectomía ab externo. Highlights of ophthalmology. 1991;19:59-66
13. Maldonado-Bas A, Maldonado-Junyent A: Filtering Glaucoma Surgery Using an Excimer Laser. J Cataract Refract Surg – Sept :
14. Maldonado-Bas A, Maldonado-Junyent A: Ultimas innovaciones en los Glaucomas: Cirugía Filtrante con Laser Excimer. ED Highlihts of Ophthalmology Cap 25:
15. Stegmann, R., Pienaar, A., et al: Viscocanalostomy for open-angle glaucoma in black African patients. J Cataract Refract Surg 1999; 25:
16. Johnson DH & Johnson M: How does non-penetrating glaucoma surgery works?. In Mermoud A and Shaarawy T (Eds) (2001): Non-penetrating glaucoma surgery. Martin Dunitz Ltd, United Kingdom. Chapter 4.
17. Stegmann, R.(2005) New microcatheter provides light at the end of the tunnel for glaucoma surgery. Eurotimes Vol 10 Issue 9:6-7.
18. Kotera, Y. Hayashi, H., et al: Short-term outcome of trabeculotomy by modified deep sclerectomy. Japanese Journal of Clinical Ophthalmology 2005; 59;9:
19. Lüke, C., Dietlein, T., et al: Phaco-trabeculotomy combined with deep sclerectomy, a new technique in combined cataract and glaucoma surgery: complication profile. Acta Ophthalmologica Scandinavica 2007;85:2: