|Year : 1983 | Volume
| Issue : 6 | Page : 781-784
Diagnostic problems in ocular hypertension
NN Sood, AK Grover, HC Agarwal
Dr. Rajendra Prasad Centre for Ophthalmic Sciences All-India Institute of Medical Sciences Ansari Nagar, New Delhi, India
N N Sood
Dr. Rajendra Prasad Centre for Ophthalmic Sciences All-India Institute of Medical Sciences Ansari Nagar, New Delhi
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sood N N, Grover A K, Agarwal H C. Diagnostic problems in ocular hypertension. Indian J Ophthalmol 1983;31:781-4
Ocular hypertension was a by product of the glaucoma surveys which revealed a large population with higher than statistically normal intraocular pressures, without any signs of field or disc changes., Perkins defined ocular hypertenision as an intraocular pressure equal to or' greater than 22 mm. Hg in one or both eyes as measured by applanation tonometry on two or more occasions with no glaucomatous field defects, an open angle and no history suggestive of closed angle glaucoma. Numerous studies on the subject have appearred in the world literatrure, but to the best of our knowledge, no work on ocular hypertension is available from India.
| MATERIAL & METHODS|| |
90 patients with a preliminary diagnosis of ocular hypertension, referred to the Glaucoma clinic on the basis of a schiotz recording of 3/5.5 gm. or 5.5/7.5 gm. weight or less with normal discs and normal chamber depth were included in the study. The patients were subjected to a full glaucoma work up which included a detailed history (including a history of use of steroids, family history and history of any systemic illness), refraction, repeated Goldmann applanation tonometry, exclusion of abnormal scleral rigidity, gonioscopy and exclusion of presence of diabetes and Goldmann perimetry. Selected subjects were subjected to monitoring of diurnal variation of intraocular pressure, water drinking test, outflow facility and colour fundus photography.
| Observations|| |
Only 69 out of the 90 patients referred with a provisional diagnosis of ocular hypertension were established to be ocular hypertensives at the conclusion of investigations.[Table - 1]
Age & sex distribution
The age & sex distribution is shown in [Table - 2] .
Family history of open angle glaucoma was obtained in 13 of the patients (18.8%).
16 of the patients we're either known diabetics or detected to be diabetic on screening (23.2%)
Other systemic problems
10 patients had systemic problems other than diabetes mellitus. 7 patients were hyper tensive, 2 had coronary artery disease (one hypertensive) and 2 had cerebro vascular disease (both hypertensive). One patient has hypothyroidism and one showed maniac depressive psychosis.
Intraocular pressure: [Table - 3]
13 of the patients were myopic (18.8%) 3(4.3%) of these had a myopia of mrore than 6 diopters.
was present in one patient (both eyes) (1:56% of the eyes).
One patient had a super-temporal branch vein block.
| Discussion|| |
The glaucoma surveys have established that the intraocular pressure distribution kin the general population does not follow a normal Gaussian curve but shows a distinct skewing of the curve towards the higher pressure levels. However, the diagnosis of ocular hypertension by surveys in general population has a number of inherent drawbacks. Besides the expense of immense effort that it involves, a number of subject could be missed because of the known diurnal and long term cyclical 5 variations in intraocular pressure.
A wrong diagnosis of ocular hypertension (false positives) can result from a number of factors. The most importatnt causes of exclusion of cases provisionally labelled as ocular hypertensives was non reproductibility of high intraocular pressure recording on subsequent repeated applanation tonometry. This could possibly be due to a fallacious schiotz tonometric recording, which could be a result of an instrumental error, an uncooperative patient or operator errors. A high scleral rigidity was the cause of high schiotz tonometry recording in one of the patients. A thorough biomicroscopic examination and gonioscopy must be done to exclude cases of glaucoma secondary to uveitis and angle closure glaucoma. Goldmann perimetry picked up glaucomatous defects in two subjects, whose discs were clinically assessed to be physiological, thus excluding them from the definition of ocular hypertension. Another important cause to be excluded is the steroid induced ocular hypertension. A history which suggested steroid induced rise of pressure was obtained in three subjects in our series, suggesting the importance of this entity. Tonography can exclude the rare patient of hypersecretion glaucoma who may also present with a clinical picture akin to ocular hypertension. excluded is the steroid induced ocular hypertension. A history which suggested steroid induced rise of pressure was obtained in three subjects in our series suggesting the importance of this entity. Tonography can exclude the rare patient of hypersecretion glaucoma who may also present with a clinical picture skin to ocular hypertension.
A significant number of patients in the study (14.5%) were in the fourth decade. The observations could suggest the earlier occurrence of raised introcular pressure in Indians and the importance of including this age group in glaucoma surveys. An equal number of males and females were diagnosed as ocular hypertensive in the present study. A number of studies from abroad report significantly high mean intraocular pressure values in women then in men, while other fail to find such a sex difference.
A high rate of positive family history of glaucoma (18.8%) and prevalence of diabetes mellitus (23.2%) has been observed in this study. This could partially be a result of the fact that the coular hypertensives have been picked up from a hospital, rather than from a survey in general population. However, a genetic component to the inheritance of ocular hypertension has been pointed out. A number of studies have shown an association of increased intraocular pressure with juvenile diabetes as well as the adult onset diabetes. The ocular hypertensives in the Framingham Eye study had a higher range of mean casual blood sugars (1.5 - 22.5 mg./ml.) than the comparable age and sex normotensive control groups.
The distribution of intraocular pressure in the ocular hypertensives in this study showed 32.8% with a pressure of less than 25 mm. Hg and 71.9% of less than 30 mm. Hg. It is this large group of patients who constitute a difficult problems both from the point of view of diagnosis and the decision regarding management.
The diagnosis of ocular hypertension must only be made after a careful history taking and extensive glaucoma work up. A number of difficulties and pitfalls must be consciously avoided in arriving at the diagnosis.
| Summary|| |
90 patients with a preliminary diagnosis of ocular hypertension poresenting to this glaucoma clinic were included in a prospective study. Preliminary referral was based on a high schiotz tonometric recording (of 5/5.5 gm. or 5.5/7.5 gm. wt. or less in the O.P.D. with normal discs & normal chamber depth. The patients were subjected to a full glaucoma work up. The final diagnosis of ocular hypertension was based on a minimum of two applanation readings of more than 21 mm. of Hg on different occasions.
23% of the patients were detected to be diabetic. Vertical studies on these cases are in progress and nearly 40% of the cases have a follow up of over 1 year. Studies with a longer follow up period and at a number of different centres need to be undertaken.
| References|| |
Linner, E. and Stromberg, U. 1967 In W Leydhecker (Ed.) Glaucomas Tutzing Symposium. Basal Karger, P 187.
Hollows, F.C., and Graham, P.A. 1966 Brit, J Ophthalmol. 50:570
Perkins, E.S. 1966 Trans. Ophthalmol Sec. U.K 86:199.
Kitazawa Y. Horie T. 1979 Glaucoma Update - Berlin, Heidelberg, New York, Springer Verlag: 169-176.
Stromberg U. 1962 Acta ophthalmol (kha.) Suppl 69.
Armaly, M.F. 1965 Arch. Ophthalmol. 73:11-18.
Kawn, HA, Leibowitz, HM, GanleyJ.P. 1977 Am.J Bpidemiol 106:33-41.
[Table - 1], [Table - 2], [Table - 3]