A C T A O P H T H A L M O L O G I C A V O L . 5 4 1 9 7 6

Deiiartment ol Ophthalmology (Head: G. C . Soon'), Jriwuhrir L d Ipictitzrte of Post-graduate Medicril School

& Rcjscarch, India

TREPHINE SECTIONS FOR CATARACT SURGERY

BY

SHASHI KAPOOR

In 100 cases of senile cataract keratoplasty trephine was used for making lamellar cataract sections from the 3 to 9 o'clock position. The results a re compared with sections made by keratome and scissors. The advan- tages achieved by performing the sections with the trephine a re dis- cussed. Complications due to defective wound healing are reduced to the bare minimum. There was no astigmatism in 41 "/o of the cases. T h e sections were ab externo enabling preplaced sutures to be inserted.

Key-words: trephine - cataract section - astigmatism - limbus.

Cataract sections are made widely with instruments such as the keratome, Bard Parker knife, Graefe's knife and razor blade. Corneal scissors are used when the sections have to be extended.

The main disadvantages of these sections is their variable degree of irregu- larity, and the uncertainty involved in the placing of the sections, resulting in an unpredictable degree of astigmatism (Kiffney & Stocker 1960; Bodian 1961; Elenius & Karo 1968; Iliff & Khodadoust 1968; Witmer & Kreinebuhul 1971; Pohjanpelto 1975). To overcome these disadvantages the Castroviejo kerato- plasty trephine was used for making cataract sections.

Received April 1, 1976.

320

Tre[>hine Section,\

Material and Methods

After the injection of local anaesthesia an 1 1 inm Castroviejo keratoplasty trephine, with its obturator withdrawn 0.6 mm behind the cutting edge, is placed over the upper limbus and tilted towards the operator in such a way that it is only in contact with the upper limbus. The trephine is rotated between the thumb and middle finger of right hand and a lamellar inark is made in upper 180 degrees of the limbus. One preplaced suture is inserted at the 12 o’clock position. The anterior chamber is opened with the tip of a cataract knife. The section is extended with corneal scissors through the previously made lamellar incision. After performing a peripheral iridectomy, intracapsular lens extraction is performed. The suture is tied and air is injected into the anterior chamber.

This technique was used in 100 cases of senile cataract. To compare the results, sections were made with the keratome and scissors in a further 100

patients. The patients were followed-up for 6 weeks. Retinoscopy was performed one week and 6 weeks after operation.

Table I. Postoperative complications in cases operated on for cataract with keratoplasty

trephine sections. ~

Complication

~

I Number of cascs

Iris prolapse

Hyphaema

Iris prolapse

Hyphaema +

Wound ectasia Striate keratitis

Collapsed anterior chamber

first postoperative day third postoperative day mild severe

first postoperative day third postoperative day (traumatic)

mild moderate severe

till third postoperative day

nil 2 2 nil

nil 1

1 1 2 nil

2

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Shaslii Kapoor

Table 11. Astigmatism 1 week postoperatively in cases with trephine sections.

0 17 - - - 17 0.25-1 D - 3 15 0 18 1.25-2 D 9 11 2 22 2.25-3 D - 11 3 0 14 More than 3 D - 22 5 2 29

Total 17 4 5 34 4 100

-

Resu I ts

In the postoperative period the patients were examined for any complication arising as a result of defective wound healing, such as a ragged or leaking wound, shallow or collapsed anterior chamber, iris prolapse or hyphaema. The encountered complications are listed in Table 1. Observations on the behaviour of astigmatism in cases where the sections were made with the trephine are

Table I l l . Astigmatism 6 weeks postoperatively in cases with trephine sections.

Type of astigmatism

Spherical 1 With rule IAgainst rule1 Oblique

Cylindrical correction Total

- - - 0 41 41 0.25-1 D 7 19 1 27 1.25-2 D - 2 25 1 28 2.25-3 D 0 4 0 4 More than 3 D - 0 0 0 0

Total 41 9 48 2 100

-

-

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Trephine Sections

Table IV. Behaviour of astigmatism from 1 to 6 weeks postoperatively in cases with

trephine sections.

Nature of astigmatism one week postoperatively

Nature of astigmatism six weeks postoperatively

Spherical 1 7 6 3 6 0 With rule 45 1 7 0 28 0 Against rule 34 14 6 14 0 Oblique 4 2 0 0 2

Total 100 41 9 48 2

given in Tables 11-IV. Spherical corrections alone were observed in 41 O/O of the cases with trephine sections and 21 O/O of the cases with keratome sections (f' < 0.05).

Discussion

The position and the regularity of the cataract section are two factors of utmost importance for the ocular behaviour in the postoperative period. With the usual methods of performing cataract sections, both of these factors are most unpredictable. The disadvantages are overcome by making the sections with the keratoplasty trephine. The sections are not only regular, smooth and sharp but also slightly oblique due to the tilt given to the trephine. The sections are ab externo where preplaced sutures can be inserted, enabling accurate edge to edge apposition of the wound. Crushing of the tissues by the scissors is minimized as the section has previously been partially completed. This markedly reduces the chances of complications and the degree of astigmatism. By means of the new technique, no astigmatism was observed in 41 O/O of the cases, whereas with other methods it has been found in 14 O/o and 22 O/O (Kiffney & Stocker 1960), 15 O/O (Bodian 1961), 1 7 O / O and 22 O/O (Pohjanpelto 1975) and 21 O/O of our own cases.

When the keratoplasty trephine is used for making cataract sections, not

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Shnshi Kapoor.

only the sclerocorneal junction but also the conjunctiva is incised. The con- junctiva can be easily retracted while placing the sclerocorneal suture. This avoids its inclusion into the wound edges. Bleeding while making the section is minimal, as the sections are limbal. Striate keratitis is negligible because of the proper edge to edge wound apposition and the least possible crushing of the tissues.

References

Bodian M. (1961) A new suture for cataract surgery. Amer. 1. Ofjhthnl. 5 1 , 1243-1248. Elcnius V. & Karo T. (1968) Changes in the refractive powcr of the cornea after

I l if l C. E. & Khodadoust A. (1968) Control of astigmatism in cataract surgery.Anzzi.

KifCney C. T. 8c Stocker F. W. (1960) Plain versus chromicized catgut sutures in

Pohjanpelto P. E. J. ( I 975) Cataract incision: Knilc incision versus stepped incision.

Witmer R. & Kreienbuhul R. (1971) Cataract incision. Graded incision ah externo

cataract extraction. E y c , E m , Nose T h . Mon. 47, 66-70.

I . Ophthal. 6 5 , 378-382.

cataract surgery. Anaer. J . Ophthal. 49. 7 1 1-713.

Actcl o p h t k ~ l . (Kbh. ) 53, 83-88.

compared with the cataract knife. Klin. Mbl . Augmheilk. 1 ~ 5 8 , 465-470.

Aulhor’s addrcrs: Dr. Shashi Kapoor, Department of Ophthalmology, Jawahar La1 Institute of Post-graduate Medical Education SC Research, Pondicherry-6, India.

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