|Year : 1966 | Volume
| Issue : 1 | Page : 17-20
Gonio-sweeping with vitreous suction in malignant glaucoma
M. U. Institute of Ophthalmology & Gandhi Eye Hospital, Aligarh, India
|Date of Web Publication||12-Jan-2008|
M. U. Institute of Ophthalmology & Gandhi Eye Hospital, Aligarh
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Nath K. Gonio-sweeping with vitreous suction in malignant glaucoma. Indian J Ophthalmol 1966;14:17-20
Malignant glaucoma, one of the most dreaded of ophthalmic conditions was described a century ago by von Graefe (1869). It is essentially an angle closure type of glaucoma following intraocular surgery, including that for glaucoma. Such eyes have a predisposition for angle closure because of certain anatomical factors already present, upon which surgery finally pulls the trigger.
The following features are present in malignant glaucoma:
1. It is a closed angle type of glaucoma.
2. Anterior chamber is extremely shallow or absent.
3. The tension of the eye is very high and is not fully controlled by diamox, intra-venous infusions and/or miotics.
4. The lens-zonule diaphragm moves forwards due to the rotation of ciliary bodies with age, rise of tension in the posterior chamber and increased hydration of the vitreous (Reese, 1950).
5. When it occurs in one eye, it is certain to develop in the other eye, unless peripheral iridectomy has been performed in the normotensive stage (Chandlar and Grant, 1962).
It the above features are kept n view in the management of such cases, one should try to open up the closed angle by medical or surgical means, decrease the mobility of lens-zonule diaphragm and decrease the hydration of the vitreous.
Malignant glaucoma has many points in common with chronic congestive glaucoma for in the late stages of the latter condition, after repeated attacks of exacerbations and remissions (Philips 1955) and "on-off phenomenon" in the angle (Smith 1954) the closure of the angle becomes complete. Further, retention of aqueous in the anterior and posterior chambers causes hydration and swelling of the vitreous which further embarasses the outflow mechanism as in malignant glaucoma. Peripheral iridectomy though useful in the early stages of chronic congestive glaucoma becomes useless in the later stages when angle-closure becomes irretrievable. [Table - 1]
In malignant glaucoma which occurs after intraocular surgery, opening the eye ball which has an extremely narrow angle and the postoperative course ultimately determine the complete closure of the angle. The mechanism of such a closure begins with the escape of aqueous when the eye ball is opened. Because of the narrow angle prevailing, the iris sticks like a wet cloth on to the posterior surface of corneo-sclera when the eye ball is opened. If this apposition does not open up soon after the close of the operation, synechiae form and seal off the angle completely. Aqueous retained in the remains of the anterior chamber and in the posterior one causes a swelling of the vitreous (Reese, 1950) and forward displacement of the lens-iris diaphragm, further narrowing the angle. A vicious circle is thus established and a malignant glaucoma results a few days after the operation.
In those cases where a drainage operation has been performed and malignant glaucoma has resulted two mechanisms are possible. The operation must have been performed for a narrow angle glaucoma. The shallowness of the anterior chamber is not altered by this operation because the flow of the aqueous at a higher pressure gradient from the posterior chamber is directly towards the subconjunctival area of absorption of aqueous where the pressure gradient is lowest. Continued shallowness of the chamber encourages synechia formation across the natural drainage canal of Schlemn. From thereon the vicious circle, described earlier, begins, hydration and swelling of the vitreous completing the sequel of events that lead to the malignant state.
A similar mechanism prevails when a peripheral buttonhole or a broad iridectomy has been performed in the early stages of an acute congestive glaucoma. In such cases, the setting of the stage is similar as above-a narrow angle, a forward rotation of the ciliary body pushing the iris-lens diaphragm forwards and a swollen vitreous. Escape of aqueous on opening the eye ball pulls the trigger that sets the drama of malignant glaucoma rolling. The iris comes into further apposition with the cornea and since the additional pressure required to restore the depth of the anterior chamber is not available because of the aqueous in the posterior chamber reaching the natural drainage channels directly, peripheral anterior synechia form opposite to where the iris is not cut away. In this case hydration of the vitreous and forward displacement of the lens-iris diaphragm are there already and not built up as in the previous consideration and the success of a correctly performed iridectomy will depend upon how much of these contributing factors are present already and are capable of regression. With the operation procedure the angle can be opened up for drainage in the operated sector, but the other parts of the angle must also open up secondarily for a permanent and effective normalisation of tension.
| Management of Malignant Glaucoma|| |
Prophylaxis: While doing glaucoma surgery in narrow angle cases one should be aware of malignant glaucoma as a complication. Before putting up the patient on table, the tension in these cases should be controlled by using prior diamox, miotics, intravenous infusions and glycerol etc. This would lessen the inflow of aqueous, decrease the hydration of vitreous and eliminate the push by the vitreous and lens anteriorly during and after surgery. To prevent the prolonged contact of iris with comeo-sclera, one should see that the chamber is well formed preferably on the table and remains so after the operation. If necessary saline may be injected in the anterior chamber. Opening of the angle can be further facilitated by use of miotics on the table and post operatively. In addition diamox etc. should be continued for few days after surgery till the section has healed and the chamber remains well formed. Broad iridectomy if at all performed should be at the true iris root.
| Goniosweeping|| |
Once malignant glaucoma has set in, the problem can be attacked with a view to decrease the vitreous volume, thereby eliminating the push by the lens and opening up the angle. Prior control of tension by diamox, glycerol, miotics and infusions would decrease the hydration of vitreous and open the angle as much as possible.
Further opening of the angle is undertaken after examination of the angle by scleral transillumination (Drance & Schneider, 1963) if possible. The tension is brought down to 20-30 mm. of Hg by medical treatment. After preliminary preparations, a broad limbal based flap (6-8 mm.) is prepared, a groove is made at the limbus and the eye is opened by an ab-externo incision 4-5 mm. long. The pseudo-angle is opened by gonio-sweeping, which consists of introducing an iris repositor at the 12 O'clock position into the angle in between the iris and sclero-cornea for 2-3 mm. or so from the limbus keeping its upper surface close to the sclerocornea without damaging the endothelium. Other meridia in the upper quadrant are similarly dealt with. Subsequently the repositor is moved in a circular manner to break the remaining synechia;. In a similar manner the outer, inner and lower angles are swept clean. Cases in which the tension has been very high, about 5-10 minims of vitreous is aspirated by a lacrimal syringe with a thick cannula at 12 O'clock position. The cannula is introduced in between the lens periphery and the ciliary body through the peripheral button hole of the iris or the broad iridectomy performed already at the time of first operation. The bulge of the lens has to be the guiding factor is assessing the amount of vitreous to be drawn out. When requisite amount of vitreous has been drawn, the lens falls back in its normal position.
If the operation has been successfully performed there would he no difficulty in forming the anterior chamber on the table. A deep chamber would form after injecting saline following withdrawal of vitreous and goniosweeping. 2-3, six zero catgut corneo-scleral sutures are applied followed by stitching of the flap. A sub-conjunctival injection of 200,000 units of crystalline penicillin with 3i gm of streptemycin is given and pilocarpine 4% drops with contractine ointment is applied. A binocular bandage is given for a couple of days. The patient is nursed flat for two days in order to keep the iris and vitreous away from the section and corneo-sclera and to maintain the anterior chamber angle open.
| Results|| |
Three cases of malignant glaucomas which occurred between 1962-64 were first medically treated and later were operated upon, after the control of the tension. The angles were swept clean all round followed by removal of a little vitreous by a lacrimal syringe and cannula till the lens bulge subsided. The lens was clear in all the three and was therefore left in situ. All these cases had narrow angle glaucoma. The first two occurred following peripheral iridectomies on the 8th and 11th post-operative days while the third occurred on the 15th post-operative day following a broad iridectomy. In all the three the anterior chamber remained shallow inspite of diamox and miotics and finally pain and high tension developed. Goniosweeping and vitreous removal was adopted as a desperate measure.
Post-operatively the patients were kept locally on pilocarpine 4% drops, contractine and hydrocotisone ointment once daily. They were also administered irgapyrin injections 5 ccs on alternate days intramuscularly.
In all the three, the eyes quieted down and the tension was normalised. They were dicharged on 15th, 18th & 36th days after the operation. The stay of the third case got prolonged as it developed massive choroidal detachment on the 6th day. No recurrence of glaucoma has been reported in any of the three cases although 2 years have passed when the first case was operated and four months for the second case. The last case which occured following broad iridectomy was operated about one and a half year ago.
| Discussion|| |
Chandler and Grant, (1962) who advocated mydriatic - cycloplegic treatment in malignant glaucoma, believe that once malignant glaucoma develops further glaucoma operations are futile. Chandler (1951) advocates that the treatment of choice is prompt extraction of lens even though it is clear. Even after the lens extraction, the malignant course may continue which Shaffer (1954) advocates opening or incising the hyaloid.
The author after managing three cases of malignant glaucoma during the last 3 years feels that an eye has a reasonable chance of recovery after the operation for malignant glaucoma by the technique mentioned above and that the lens, if clear can safely he left behind provided one has swept the pseudo-angle clean, removed a little vitreous by a lacrimal cannula and eliminated the bulge on the lens. Simple air injection, extraction of a clear lens or posterior sclerotomy alone do not give quick and lasting good results as the benefit is limited, the results uncertain.
| References|| |
Chandler P. A. (1951), Amer. J. Ophthal., 34: 995.
Chandler, P. A. and Grant, VV. M. (1962) A.M.A. Arch. Oph.
Drance, S. M., Schneider, R. J., (1963), Amer. J. Ophthal., 55: 797.
Hobbs, H. E. and Smith, R., (1954), Brit. J. of Ophthal., 38: 283.
Philips. C. I., (1956), Brit. J. of Ophthal. 40: 136.
Reese, A. L. (1950) Trans. Amer. Oph. Soc., 48: 140.
Shaffer, R. N. (1954), Trans. Amer. Acad. Ophthal. (Otolarving. 58: 217.
Smith, R, (1954), Brit. J. of Ophthal., 38: 136.
Von Graefe, A., (1969) Arch. of Ophthal., 15: 108.
[Table - 1]