|Year : 1964 | Volume
| Issue : 1 | Page : 29-31
MS Nirankari, Daljit Singh, Om Parkash
Department of Ophthalmology, Medical College, Amritsar, India
|Date of Web Publication||13-Feb-2008|
M S Nirankari
Department of Ophthalmology, Medical College, Amritsar
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Nirankari M S, Singh D, Parkash O. Iridoschisis. Indian J Ophthalmol 1964;12:29-31
Lowenstein and Foster (1945) described a case showing a rare type of iris atrophy in which separated iris fibres floated in aqueous like seaweeds. Their search of literature revealed 8 such previously recorded cases : The iris in all these cases "looked as if teased by a crochet hook" (Sander). None of them made any histological study nor advanced any theories of causation.
it remained for Lowenstein and Foster (1945) to describe a case, do histopathology, put forward theories of causation and christen the condition as IRIDOSCHISIS.
Since then many more cases have been described: Lowenstein Foster and Sledge (1948), Linn and Linn (1949), Veirs (1949), Mc Culloch (1950), Me Moffat (1950), Haik Wood and Waugh (1952), and several others. None except Lowenstein and Foster (1945), Lowenstein Foster and Sledge (1948) and Albers and Klein (1958) have made histopathological studies.
Case Report: [Figure - 1].
S.S., 51 years old male, a school teacher was admitted to Ram Lal Eye Hospital, Amritsar, on 2.9.1960 with the diagnosis of acute glaucoma R.E. He presented with the history of acute pain in the right eye and temple preceded by haloes seen around lights and accompanied by nausea and vomiting for the last two days. Ten days prior to this episode, his eye looked pink for a day, but was relieved without any treatment.
Tension at the time of admission was 52 mm Hg.
Biomicroscopy of the Iris.
(Done one week after the admission).
Periphery of the iris consisted of iris tissue in the form of a ring anterior synechiae, about 1 mm broad, varying slightly in width in different parts of the circumference, but greater in the outer and lower portions.
Pupillary zone was normal. The margin was intact and moved smoothly over the underlying lens surface, showing free excursions of iris with reaction to light.
Middle zone showed interesting features. It appeared as if it had been teased with a needle. The stroma was split up into loose mixture of large number of pigmented and white atrophic strands running in all directions, but mostly from the periphery to the collarette. The arrangement of the fibres was quite irregular. The strands had a peculiar dry and rough appearance not unlike jute fibres. Thickness of fibres and width of their meshes were variable, the fibres being thicker and meshes more open at the periphery. Iris showed depressions, the dark posterior epithelium being visible in the more intact areas the iris tissue was very much loosened and the separated strands were floating in the aqueous.
Gonioscopy showed that the angle was completely blocked.
The patient was put on the standard regime of glaucoma treatment consisting of Eserine 1 % drops instilled every quarter of an hour and pilocarpine 2% drops one hourly. Analgesics were given to relieve pain. Tension failed to respond with the above treatment, but came down promptly on administering Diamox one tablet three times a day. Medical treatment was carried out for one week only. The tension was maintained at 18mm Hg without further medication. On the 15th day of admission, peripheral iridectomy ab externo was performed. Tension remained normal in the postoperative period. Cortisone ointment was prescribed for one month. Since his first appearance on 2-9-1960, the patient has been under observation. The tension never rises above 19mm Hg. The vision has remained 6/6 in both the eyes without correction.
Histopathology of the Iris Tissue
The report given below is by Dr. Greer of Melbourne.
Section shows a small fragment of heavily pigmented iris tissue. The iris tissue is possibly a little fibrotic and atrophied and several small clefts are evident in the substance. The vessels are not obviously abnormal although the endothelial lining of some of them is swollen. Some aggregation of melanophores is seen on the outer aspect of their sheaths, but this is not, I think abnormal. The tissue is much folded, but part of the dilator muscle and fragments of posterior epithelium can be recognised. There is no inflammatory infilteration.
| Discussion|| |
The causation of iridoschisis is as yet undecided. Lowenstein and Foster (1945) suggested that "Cleavage of the iris in this particular plane may have an anatomical basis as E. Fuchs has described a certain degree of separation of the anterior and posterior iris stroma. They feel that exaggeration of this normal condition may lead to the separation of the two layers. They also suggest an "atrophic effect of lytic substances in the aqueous, originating in glaucomatous metabolism, but this plays only a secondary part, if at all to purely senile changes."
Albers and Klein also ascribe the changes in the iris to ageing process.
Dymitrovska and Rogalski presented a young case with microcornea and iridioschisis. The cause in their case was thought to be developmental.
In our case only one eye was affected. The anterior layers of the iris were projecting forwards. In addition the elements of the anterior layers were found to be loosening away in the form of separate fibres. Some of the fibres were broken and were lying curled up.
In our opinion the condition is much more than mere loosening of the anterior stromal layers. There must be a strong lytic factor which causes such wide spread break up of the iris tissue. The sphincter and the blood vessels are not much affected in this process. The normal stromal tissue of the middle zone of the normal iris has small quantities of hyaluronic acid. Can this extensive degeneration of iris be related to derangement of this mucopolysacchride ? Histopathological studies on this line may give some clue to the aetiology of the condition.
The cause of the acute attack of glaucoma is evident. But the reason why the tension is normal in spite of the presence of a completely blocked angle is not clear. Probably the opened up iris meshes have taken up the function of reabsorption of large quantities of aqueous. Or perhaps similar degenerative changes are also occuring in the ciliary body, leading to decreased secreation.
| Summary|| |
A case of iridoschisis is described. The histopathological findings are given and aetiological factors are discussed.
| References|| |
Lowenstein, A., and Foster. J. (1945), Brit. JI. Ophth., 29: 277.
Lowenstein, A., and Foster, J. and Sledge. S. K. (1948), Brit. J. Ophth., 32: 129
Linn, J. G. and Linn (Jr.) J. G. (1949), Amer. J. Ophtha.., 32: 1700.
Veirs. E. R. (1949), Amer. J. Ophthal, 32: 262.
Mc Culloch. C. (1950). Amer. J. Ophth., 33: 1398.
Mc Moffat, P. 1950), Proc. R. Soc. Med. Vol. 43: P. 1011.
Haik, G. M., Wood, L., and Waugh, R. L. (1952), Arch. Ophth. Chicago, 48: 40.
Sedler-Dymitrovska, M. and Dzierzykraj Rogalski. T. (1954), Klin oczna., 24: 207.
[Figure - 1]