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ARTICLES |
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Year : 1983 | Volume
: 31
| Issue : 3 | Page : 273-276 |
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Hypotony for intraocular surgery
Daljit Singh, Inderjit Kaur
Department of Ophthalmology, Medical College, Amritsar, India
Correspondence Address: Daljit Singh Department of Ophthalmology, Medical College, Amritsar India
Source of Support: None, Conflict of Interest: None | Check |
PMID: 6676237
How to cite this article: Singh D, Kaur I. Hypotony for intraocular surgery. Indian J Ophthalmol 1983;31:273-6 |
A soft eye for intraocular surgery, especially cataract operation offers extra margin of safety. A concave cornea at the end of cataract extraction is a source of great comfort to the surgeon.
We present our experience with the various methods which can be used to produce hypotony. The following methods have been studied:
1. Acetazolamide[1]: 500 mgm., 2 hours before operation.
2. I;V mannitol[2] : 1 Gm Kg. body weight.
3. Oral Glycerol[3] : 3 Oz. with water 2 hours before operation.
4. Retrobulbar injection: 2 % solution, 1.2 cc., of xylocaine[4] 5 minutes before operation.
5. Retrobulbar injection: 0.5 %, 1.2 cc., 15 of marcaine[4] minutes before operation.
6. Timolol[5]: 0.5 %, one drop topically, 12 hours and 2 . hours before operation.
7. Ocular compression[6]: By a special apparatus with 30 mm. Hg. pressure for 20 minutes.
25 patients were studied in each group. Besides the routine examination, ocular tension was studied with Maklakoff-Filatov tonometer: 1. Before the application of the procedure or drug.
2. Immediately after the application of the procedure or at a time when the drug is supposed to have the maximum effect.
3. Just before operation, i.e. after retrobulbar anaesthesia.
4. Postoperative ocular tension was recorded after 24 hours, 48 hours. 72 hours and 96 hours.
In every case cataract was removed by extracapsular microsurgery. The irrigation was done by Lactated Ringer solution. The incision line was closed carefully with 5 to 7 stainless steel 50 micron sutures.
The side effects of the various procedures for producing hypotony were noted.
Description of the apparatus used for ocular compression
The apparatus is prepared out of an ordinary blood pressure apparatus with an infant-sized cuff. The cotton covering over the rubber cuff is removed. For effecting ocular compression we proceed as follows:
The eye is closed and a sterile eye pad is placed over it. The rubber cuff of the infant blood pressure apparatus is placed over it. Then a light bandage is used to keep the cull in place. The cuff is now connected to a dial type of blood pressure apparatus and the dial is kept by the side of the patient's head [Figure - 1]. The cuff is inflated so that the inside pressure goes to 30 mm. Hg., where it is maintained for 5 minutes. 4 Such periods of pressure are given with pauses of I minute.
Results | | |
[Table - 1] shows average intraocular pressure reduction by various methods preoperatively.
If general anaesthesia were to be given for surgery, the levels of intraocular pressure achieved would be as in the column of "Time of maximum action".
Postoperative Intraocular Pressure Charges
The average postoperative intraocular pressure by the various methods of hypotony 24, 48, 72 and 96 hours is shown graphically in [Figure - 2].
Side Effects
The general side effects with the various methcds are shown in [Table - 2].
Discussion | | |
Recording intraocular pressure in the postoperative period can be a hazardous procedure, since the pressure of the tonometer on a recently operated eye may cause a leakage.
In our series however, the success of this study depended upon fairly foolproof closure of the incision line with steel sutures The incision line was itself small (10 mm ) as all cases were operated by extracapsular microsurgery method.
Pre-operatively, maximum hypotony was achieved by ocular compression, followed by xylocaine, mannitol, marcaine, timolol, diamox and glycerol. The ocular hypotony achieved by ocular compression was most dramatic with an average fall of 10.7 mm. Hg.
In the first 24 hours after surgery, the tension rebound was maximum with glycerol followed by mannitol, ocular compression, marcaine, diamox, timolol and xylocaine.
There was a gradual fall in intraocular pressure over the next three days, with all the methods.
The average pressure 96 hours postoperatively tended to be in the range of 14.2 to 16.4 mm. Hg. with the various methods. The ocular tension was highest after ocular compression (average 16.4 mm. Hg.) and lowest with marcaine (average 14.2 mm. Hg.).
The methods relying upon osmotic action (glycerol and mannitol) showed poor effects preoperatively as well as post-operatively.
Oral glycerine and IiV mannitol are attended with many unpleasant side effects and their use is better avoided for most cases.
Acetzolamide 500 mgm in a single dose, anaesthesia with xylocaine, anaesthesia with marcaine, local instillation of timolol and ocular compression are not accompanied by any side effects. Marcaine analgesia lasts for a long time and most patients would not need pain relievers in the post-operative period.
It appears to us that a judicious combination of the various methods that have no side effects, will produce ocular hypotony to any desired level. For obtaining satisfactory hypotony ocular compression as described being most effective should be common to all combination.
References | | |
1. | Richardson, K.T., Arch. Ophthal., 89: 78, 1973. |
2. | Smith, E. W., Drauce, S. M., Arch. Ophthal.,68:734. 1962. |
3. | Drauce, S.M., Arch. Ophthal., 72: 123, 1964. |
4. | Wintex, F.C., Arch. Ophthal., 75: 725, 1966. |
5. | Zimmerman, T.J., Kaufman, H. E.; Arch. Ophthal., 95: 601-607, 1977. |
6. | Gills, J.P., and Loyd, T.L., Amer. Intra-ocular Implant Society, 5: 9, 1979. |
[Figure - 1], [Figure - 2]
[Table - 1], [Table - 2]
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