|Year : 1981 | Volume
| Issue : 4 | Page : 451-453
Corneal trephine section in cataract surgery
ST Fernandez, TP Ittyerah
Little Flower Hospital, Angamally, India
S T Fernandez
Little Flower Hospital, Angamally
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Fernandez S T, Ittyerah T P. Corneal trephine section in cataract surgery. Indian J Ophthalmol 1981;29:451-3
The procedure of sectioning an eye for cataract after a glaucoma surgery with a good filtering bleb is still a matter of controversy. Various methods of sections have been described :
- Section partially limbal and partially corneal.
- Lower Limbal section.
- Section through the bleb itself.
- Lateral section Limbal (Temporal)
With the improved suture materials available now and with the use of operating microscope, corneal sectioning in cataract surgery is becoming common. Therefore we thought that an anteriorly placed corneal section without disturbing the filtering bleb was the natural answer to this problem. A specially designed trephine was used to make a fairly deep mark enabling pre-placed sutures to be inserted and make the section clean and accurate. There was almost nil or rarely any bleeding and access to the lens was easy, the patient could be made ambulent early and discharged early.
The important part of this procedure is the correctly and deeply placed suturing.
Disadvantages of the procedure we noted were :
- Being corneal section, cases with corneal degeneration could not be subjected to this procedure.
- 8'0 virgin silk interrupted sutures placed on the cornea gave more irritation and photophobia to the patients. Of late, we have started using continous shoe string sutures with 9'0 monofilament which give excellent results.
- Not suitable when there is a dissecting bleb.
| Materials and methods|| |
The first 50 eyes in 48 patients performed in the last 3 years have been selected for this study. The maximum follow-up was 3 years and the minimum follow-up was for 6 months. 2 patients among the 48 had bilateral procedure. All patients had undergone glaucoma Surgery and Glaucoma was well controlled.
38 eyes had Scheies operation.
8 eyes had Trabeculectomies.
4 eyes had Elliots corneo-scleral trephine.
22 patients were Females and 26 patients were Males.
Corneal Trephine : The corneal trephine used for this procedure was so designed that about 1/ 3 of the edge projected smoothly forward and is sharp. The other parts of the trephine are blunt. There is a ring guard preventing the section becoming more than about 3/4th mm deep. One could see through the trephine while using the microscope and therefore correct placing of the trephine was easy. Trephines with corneal diametes of 9.5 mm, 10 mm & 10.5 mm are available and the correct diameter was assessed by placing the trephine on the cornea before the operation.
Operative Procedure : Patients were prepared as for routine cataract extraction. Retrobulbar and facial block with 2% Xylocaine were given. After routine cleaning and draping wire speculum was inserted. Superior and inferior rectus sutures were applied.
After selecting the correct diameter of the trephine, the eye ball was fixed with a fixation forceps and the section was made with the trephine with the sharp edge of the trephine facing up. By a rotatory movement of the trephine a deep cut was made. With a colibree forceps the required depth was checked and if necessary the section was deepened with a blade. 3 preplaced sutures of 8'0 virgin silk were placed. Then the cornea was perforated with a blade and with a minimal shelving the section was enlarged with Castroviejo's right and left scissors making sure that the sutures were not cut. Additional Iridectomies were done when found necessary and the lens extracted with cryo The sutures were tied and additional 4-5 sutu-. res were applied.
The procedure is now slightly modified. We use only one preplaced sutures and apply continuous sutures with 9'0 monofilament in the shoe lace pattern. Air was injected before the last suture was inserted. Subconjunctival Garamycin was routinely given. Post operatively, the patient was made ambulent immediately after the operation and discharged any day after 5 days.
Sutures were removed in 2 stages. Half of the interrupted sutures were removed after 21 days and the other half after 6 weeks. Monofilament sutures are removed only if necessary after 4-6 weeks.
Post Operative Results : There were no post operative complications. About 30% of the patients showed minimal Keratitis on the 1st day of the operation. Anterior Chamber was well foi med in all the cases and there was no history of hyphaema. Only in 3 cases, the anterior chamber became shallow after removing all the sutures after 21 days. In one case the pressure went up but was controlled after doing a Synechiotomy and air injection. The other 2 cases are still doing well with no complications.
22% had low vision due to optic disc cupping and atrophy of various grades following glaucoma.
Inspite of corneal sectioning, high cylinders were noted only in 2 eyes. This was due to the use of operating microscope and accurate and deeply placed suturing. When once the technique is perfected we hope to bring down the astigmatism to less than two diopters in all cases.
| Summary|| |
50 corneal trephine sections, made with a specially designed trephine for cataract extraction, on glaucoma cases with filtering bleb are reviewed. This procedure is simple with minimal complications provided it is under magnification by trained hands.
[Table - 1], [Table - 2]