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ARTICLES |
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Year : 1984 | Volume
: 32
| Issue : 6 | Page : 488-490 |
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Role of suturing and incision in astigmatism following cataract surgery
SV Mahesh, PN Srinivasa Kao
O.E.U. Institute of Ophthalmology, K.M.C. Hospital, Manipal, India
Correspondence Address: S V Mahesh O.E.U. Institute of Ophthalmology, K.M.C. Hospital, Manipal India
Source of Support: None, Conflict of Interest: None | Check |
PMID: 6400608
How to cite this article: Mahesh S V, Srinivasa Kao P N. Role of suturing and incision in astigmatism following cataract surgery. Indian J Ophthalmol 1984;32:488-90 |
It is a known fact that in cataract surgery there would be astigmatism produced due to healing of section. It was estimated to be about 2-I diopters against the rule during pre-suture era.
With the advent of finer suture materials of different sizes, various techniques of making corneoscleral section and different suturing techniques, degree and type of astigmatism has varied.
Material and methods | | |
A prospective study of 100 cataract operations by a single surgeon in a period of 6 months using following technique was done.
All the patients were operated by the same technique of corneo scleral section (Ab-external, posterior limbal, markedly bevelled about 135° slanting to the globe. Incision was made by Bard Parker Knife. Depth of the groove was upto the level of Descemets membrane, length of the section being about 160°. After putting a single prefixed suture at 12 O'clock, anterior chamber was entered with bent keratome and the section was enlarged on either side with universal extension scissors.
8 Zero virgin silk sutures were applied. In series I, 58 patients had single preplaced and 2 postplaced sutures and in series II, 42 patients had single replaced and 4 postplaced sutures.
All the patients underwent keratometry preoperatively and postoperatively on 15th day. Subjective refraction was noted on or after postoperative day.
Discussions | | |
Section requires proper closure with corneo-scleral suturing. Placement of suture should be good. It should not allow wound to gape either posteriorly or anteriorly. A too superficial suture may slough out too soon and may cause posterior gaping.
In [Table - 2] properly placed (3 S) suture has produced operative a stigmatism of 0.65D + 1.2 against rule and properly placed (5 S) have produced 0.61 + 1.34 D. Though statistically insignificant (5 S) has produced slightly less amount of average astigmatism. Whereas in group III where improper tying was done, marked astigmatism is produced. However, it is statistically not compared due to less number.
In [Table - 4] it shows that with this technique of section average astigmatism produced was + 0.71 D + 1.3D.
Luntz [1] in his study found that postoperative astigmatism consists of suture induced astigmatism and operative astigmatism further, suture induced astigmatism is not a problem in cases of absorbable and silk sutures because silk sutures get necrosed and extruded and absorbable get absorbed. Only in case of nylon sutures which do not get extruded. A higher amount of suture induced astigmatism is thus produced, which requires its removal.
Since in our set up, the postoperative follow up is not likely to be meticulous, the absorbable or extruding suture like silk may have an advantage over nylon.
Astigmatism in markedly bevelled incisions is less. Probably in bevelled incision the astigmatism of scleral Incision gets neutralized by the corneal incision and a minimal astigmatism is produced. It can also be made out that the astigmatism produced in this technique is less when compared to even the sophisticated techniques using surgical keratometers. For our set up probably markedly bevelled incision with properly placed deep interrupted radial equidistant sutures might minimize the postoperative astigmatism. In fact in our series subjective astigmatism is lesser than the keratometric astigmatism as shown in [Table - 2] and [Table - 3].
Summary | | |
Markedly bevelled posterior limbal corneoscleral incision closed with deep radial interrupted equidistant sutures produces acceptable minimal postoperative astigmatism. This does not require sophisticated techniques of suturing and use of surgical keratometer for control of postoperative astigmatism and has special reference for our Indian set up.
References | | |
1. | Luntz M H, 1977, Brit J, Ophthalmol 61:360. |
[Table - 1], [Table - 2], [Table - 3], [Table - 4]
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