Doyne lecture: Heterochromic iridocyclitis

274

Surv Ophthalmol 30(4) January-February

1986

CURRENT OPHTHALMOLOGY

Comment This paper marks an important contribution to our current understanding of the mechanism by which transient obscurations (TOV) occur. The authors report the obscurations encountered in four patients. Three of the patients had non-papilledematous elevation of the optic disc caused by a variety of conditions and included chronic uveitis with passive disc edema, perioptic meningioma, and optic nerve drusen. Another patient with a large posterior pole coloboma and no disc elevation had symptoms compatible with TOV. That papilledema alone is not the only factor accounting for TOV is quite true. Our first experience with such a patient occurred in an individual with bilateral disc edema caused by xanthomatous orbital tumors that encased the optic nerves. It seems obvious that TOV must represent the clinical manifestations of a transient compromise of vascular function within the optic nerve head. The postural effects on TOV frequency are probably the result of altered central venous pressure with consequent secondary effects on venous flow within the orbit and optic nerve. One word of caution. The patient with a visual loss attributed to optic nerve drusen experienced some attacks ofvisual loss that lasted as long as live minutes. Although disc congestion caused by a drusen might be the only explanation for his complaints, I was surprised that the authors did not mention that specific testing of carotid patency was done and.was normal. Transient ischemic attacks of carotid origin often cause bouts of visual loss lasting as long as five minutes. This patient’s attacks were not precipitated by postural changes, as was the case in the other three patients. Exclusion of other factors besides drusen that could be causing a relative impairment of the perfusion of the optic disc in an elderly patient must be considered. JOHN MCCFLARY III, M.D. HOUSTON, TEXAS

Doyne Lecture: Heterochromic

104:219-231,

Iridocyclitis,

by G. R. O’Connor.

Tmns Ophthalmol Sot UK

1985

Fuchs’ heterochromic iridocyclitis is a rare but significant cause ofvisual impairment. This form of uveitis is misdiagnosed more than any other disorder in the entire field of uveitis. This is particularly true among brown-eyed individuals in whom gross heterochromia may not be diagnosed for many years. The clinical presentation of Fuchs’ heterochromic iridocyclitis may include a number of general unrecognized variants among which are Koeppe nodules, transient synechia formations, and blood-filled cysts. Recently, the relationship of heterochromic iridocyclitis to posterior inflammatory lesions, such as those of toxoplasmosis, have been explored. Although the disease was once thought to be a degenerative or tropic disorder, current investigations reveal that it is a true inflammation of immunologic origin. The disorder may be related to a depression of suppressor T-cell activity. The etiology of the disease is still obscure, but in some cases an association with simple heterochromia has been found among families in whom multiple members are affected by either simple heterochromia or Fuchs’ heterochromic iridocyclitis. Corticosteroid treatment of Fuchs’ heterochromic iridocyclitis is not effective and should be reserved for those patients in whom inflammatory products obstruct the visual axis. Most patients should be treated by observation alone. Cataract and glaucoma are the most important complications. Treatment of the glaucoma is particularly difftcult and often unsuccessful. (Author’s address: Dr. G. Richard O’Connor, 22 Wray Ave., Sausolito, CA 94965).

Comment As a Doyne lecturer for 1984, Dr. O’Connor has presented an excellent review about a disease which remains enigmatic in ophthalmology. Heterochromic iridocyclitis, described in Fuchs’ classical paper of 1906, is a condition affecting only one eye in 90% of the cases and rarely observed. It may be estimated that, in Belgium, an ophthalmologist with a full-time clinical practice might detect one case every two or three years. For the members of the International Uveitis Study Group (IUSG) Fuchs’ heterochromic iridocyclitis (FHI) affects 3.2% (+ 2.45%) of the patients examined in 1982 in their uveitis clinics. As Dr. O’Connor points out, the diagnosis of FHI is often diflicult. This is because the different clinical

275

CURRENTOPHTHALMOLOGY signs are not always about

550 patients

scattered

present

at the same

with FHI,

on the whole posterior

secondary

to stromal

atrophy

time.

the most

According

frequently

side of the cornea and defects

to the information

observed (95.7%

signs

of the cases);

in the posterior

given by the IUSG

are (1) the typical

pigment

keratic

(2) hypochromia

members

precipitates,

of the iris, which is

epithelium (86.5% of the cases); (3) and (4) filiform hemorrhage following

cataract starting under the posterior capsule of the lens (83.6%) puncture of the anterior chamber (86.7% of the 75 cases examined by two IUSG members). In our experience, the cases without heterochromia of the iris are bilateral cases or dark-eyed patients. Moreover, cataract, occurring

later

during

Etiopathogeny theories

the development

of FHI

have allowed

would first inhibit

of the disease,

has been at the origin

a better

normal

understanding

development

eye would

respond

connection

has been established

is generally

of many

of the disease.

of the uveal pigment

to the pathologic

agent

between

FHI

not detectable

controversies. Fuchs

himself

in very young

sympathetic

thought

mild

disease.

chronic

involved

heterochromia.

iridocyclitis.

However,

patients.

nor hereditary

that the factors

with, as a consequence,

by an unusually and a systemic

Neither

Later

Up

some patients

the

to now,

with FHI

no

were

recently reported to have associated retinal lesions of the type found in ocular toxoplasmosis. These lesions were located in the eye with FHI, in the fellow eye or in both eyes. They could be secondary to the agent responsible

for iridocyclitis

Immunological in the aqueous intraocular against

changes humor

origin

a bacterial

immune

reactions

correspond

or to alteration were recently

from

as discussed

in immunological

28 of our 35 patients elsewhere,

to immune

complexes

FHI

examined.

They This

could be the expression

or a viral agent or against in the eyes with

response.

found in eyes with FHI.

the ocular

consist

most

of intraocular

immune

reactions

Another

in the aqueous

in 22 of our 28 cases examined

abundance

of IgG,

tissues themselves.

is the detection,

of a relative

abundance

of IgG

probably

proof of the existence

humor,

of factors

and in approximately

35%

of

directed

assumed

of to

of Dr. O’Con-

nor’s cases. These factors are probably of intraocular origin since they were detected in the aqueous humor and not in the serum, or at the same titer in both fluids, although there were large differences in their protein contents. Dr. O’Connor to a depression

evoked in his lecture of suppressor

concerning

the suppressor

Ophthalmol

(&$$d)

163:52,

even if this mechanism The possible

T-cells.

the possibility

that these intraocular

This fascinating

hypothesis,

immune

reactions

could be related

based on a work by Murray

and Dinning

activities of T-lymphocytes of blood from patients with FHI (Murray PI, et al: Acta origin. However, 1984), would have to be confirmed for the T-cells of intraocular

was confirmed,

role of viral agents

the nature

would

of the agent responsible

for FHI

would remain

unknown.

have to be studied.

To summarize, it seems obvious that FHI is an immunological disease which could be secondary to a local infection of viral or bacterial origin. Then there would be a relationship between the modern immunological theory

and the Fuchs’ theory

based

on a local infection. JEAN-PAUL DERNOUCHAMPS, M.D. BRUSSELS, BELGIUM

Evidence of Extraocular Muscle Restriction in Autoimmune Thyroid Disease, by G. T. Gamblin, P. Galentine, B. Chernow, et al. J Clin Endocrinol Metabol 61: 167-171, 1985 Patients

with Graves’ ophthalmopathy

frequently

have transient

positional

changes

in intraocular

sure, especially on upgaze, a phenomenon attributed to compression of the globe by the opposing extraocular muscles. In this study, the authors compared a group of patients with Graves’ thyroid

pres-

inelastic ophthal-

mopathy, Hashimoto’s thyroiditis, subacute thyroiditis and normal patients. Abnormalities of elevation in the intraocular pressure were sought at both 15” and 25” of upgaze. At 15” upgaze, intraocular pressure abnormalities occurred in 25% of patients with Graves’ thyroid ophthalmopathy and 13% of patients with Hashimoto’s thyroiditis. At 25” upgaze, these figures rose to 54% for Graves’ thyroid ophthalmopathy and 37% in Hashimoto’s thyroiditis. Only one of 25 normal subjects had an elevation of intraocular pressure changes on upgaze, as did one patient with silent thyroiditis, but no patients with subacute thyroiditis exhibited intraocular pressure elevations. The authors suggest that these data document the frequent presence of extraocular muscle restriction in patients with a history of Hashimoto’s thyroiditis as well as in patients with a history of Graves’ thyroid