Pseudo-tumours,a clinical concept

Space-filling lesions in the orbit can be divided into 3 large groups: 1. Acute and subacute inflammatory processes (bacterial, fungal, parasitic, foreign body). 2. Benign and malignant tumours, true new growths. 3. Pseudo-tumours. The conditions in group 3 are also space-filling lesions, but have the characteristics of a chronic, infiltrating, inflammatory process. In 11% of 340 consecutive patients in the Orbital Centre in Amsterdam this diagnosis was made. The group is far from uniform: the dominant cell type varies from one case to another. Usually lymphocytic cells are dominant; if these are arranged in follicles the lesion is called a pseudo-lymphoma. This condition can gradually leave the province of the pseudo-tumours and begin to show the characteristics of a malignant or non-Hodgkin lymphoma. Sometimes the inflammatory character of the lymphoid infiltration is dominant, as in myositis, sclerotenonitis and infiltrative Graves' ophthalmophathy; these conditions are clearly related to immunological processes.Attempts to classify all pseudo-tumours on a pathological basis have remained rather vague.Clinical picture: rapid development (2–6 months); pain and oedema are present, but these are not the principal symptoms; secondary features are: disorders of motility, visual loss and other symptoms. Bilaterality usually indicates the presence of a systemic disease.Therapy: the possibilities are treatment of the infection, corticosteriods, chemotherapy, radiotherapy and surgery.     

Tono-Pen,a new tonometer

The Tono-Pen is a miniaturized Mackay-Marg tonometer with electronic signal analysis and digital pressure display. In study 1, we compared the Tono-Pen with Goldmann tonometry in 108 healthy human subjects (216 eyes). In 33 of these subjects, the IOP was changed in a range between 0 and 50 mmHg by a scleral suction-cup system. In study 2, the Tono-Pen was compared with a Statham membrane manometer in 6 humans (12 eyes), 3–6 h after death. The IOP was changed in a range between 0 and 60 mmHg by an infusion system.—Results: Related to the Goldmann tonometer, the Tono-Pen gave a small overestimation of IOP below 16 mmHg (maximum deviation 1.5 mmHg at 0 mmHg Goldmann reading). Above 16 mmHg, however, the Tono-Pen increasingly underestimated the IOP determined by Goldmann tonometry (maximum deviation 8 mmHg at 50 mmHg Goldmann reading). Related to the manometer, the Tono-Pen gave a small overestimation of IOP below 17 mmHg and small underestimation above 17 mmHg (maximum deviation 2.5 mmHg at manometer readings of 0 and 60 mmHg, respectively).— Conclusions: Throughout the entire clinically relevant IOP range, an acceptable relationship between Tono-Pen and manometer readings was found in human cadaver eyes, whereas the relationship between Tono-Pen and Goldmann tonometric readings in the clinical study was found to be acceptable only in the low and physiological IOP range. The considerable deviation from the Goldmann readings in the high IOP range requires further modifications of The Tono-Pen.     

Evidence for spatial regularity among retinal ganglion cells that project to the accessory optic system in a frog, a reptile, a bird, and a mammal.

The vertebrate retina contains only five major neuronal classes but these embrace a great diversity of discrete types, many of them hard to define by classical methods. Consideration of their spatial distributions (mosaics) has allowed new types, including large ganglion cells, to be resolved across a wide range of vertebrates. However, one category of large ganglion cells has seemed refractory to mosaic analysis: those that project to the accessory optic system (AOS) and serve vestibulocerebellar mechanisms of motion detection and image stabilization. Whenever AOS-projecting cells have been analyzed by nearest-neighbor methods, their distribution has appeared almost random. This is puzzling, because most aspects of visual processing require the visual scene to be sampled regularly. Here, spatial correlogram methods are applied to distributions of large ganglion cells, labeled retrogradely from the AOS in frogs, turtles, and rats, and to the AOS-projecting displaced ganglion cells of chickens. These methods reveal hidden spatial order among AOS-projecting populations, of a form that can be simulated either by superimposing a single regular mosaic on a random population or, more interestingly, by overlapping three or more regular, similar but spatially independent mosaics. The rabbit is known to have direction-selective ganglion cells (not, however, AOS projecting) that can be subdivided into functionally distinct, regular mosaics by their tracer-coupling patterns even though they are morphologically homogeneous. The present results imply that the direction-selective AOS-projecting ganglion cells of all vertebrates may, likewise, be subdivided into regular, independent mosaics.     

Thick corneas,large pupils,and a giant problem

An 87-year-old woman presented 1 month after uneventful cataract surgery with ipsilateral corneal edema. She was diagnosed with pseudophakic bullous keratopathy and scheduled for endothelial transplantation. A few days later, however, she presented with bilateral corneal edema, dilated pupils, and further reduction of visual acuity. Neuro-ophthalmic evaluation disclosed a bilateral ocular ischemic syndrome causing complete visual loss. Temporal artery biopsy was consistent with giant cell arteritis. Corneal decompensation should be considered as a rare presentation of giant cell arteritis, a diagnosis that ophthalmologists should suspect in any case of unilateral or bilateral ocular ischemic syndrome.     

Iloprost, a stable prostacyclin analog, reduces intraocular pressure

Topical application of Iloprost caused a dose-dependent decrease in intraocular pressure (IOP) in rabbits and ocular hypertensive beagles. In rabbits, the IOP response was biphasic and miosis was observed. In beagles, there was no initial hypertensive phase, and the fall in IOP was more pronounced (up to 37%). In beagles, Iloprost did not influence pupillary diameter. A mild transient hyperemia was noted in both rabbit and beagle eyes. Iloprost led to an increase in the aqueous humor protein concentration in rabbits but not in beagles. The use of artificial tears as vehicle enhanced the effect on intraocular pressure but also aqueous protein in rabbits. The central corneal temperature was increased after application of Iloprost in both rabbits and beagles. In rabbits, tonography revealed an increase in outflow facility during both the hypertensive and the hypotensive phases. Iloprost caused a decrease in mean arterial pressure in beagles; the effect on pulse rate was inconsequential. It is suggested that similar low doses of an analog of Iloprost or carboprostacyclin that does not affect the hemodynamic equilibrium could be of value in the treatment of glaucoma.     

眼科新糖蛋白opticin研究

Opticin是2000年发现的一种新糖蛋白,属于富含亮氨酸的重复单位(LRR)蛋白多糖家族第三类,在溶液中以一个稳定的约90KDa的二聚体存在。Opticin主要存在于眼玻璃体中,其mRNA在多个组织中被检测到。Opticin有维持玻璃体稳定、维持玻璃体与视网膜之间连接和抑制血管生成等作用。本文综述了opticin的发现、分子结构、基因、组织分布和功能等。     

Corneal biopsy. Indications, techniques, and a report of a series of 87 cases

Corneal biopsy can be an effective aid in establishing diagnoses in a variety of infections, dystrophic and degenerative conditions, corneal manifestations of systemic diseases, and drug-induced changes. Preoperative planning and proper preparation of the tissue are stressed. In a series of 87 cases, the indications for biopsy were ulcerative keratitis in 42 cases, nonulcerative lesions in 25 cases, dystrophic and degenerative processes in 15 cases, and corneal manifestations of systemic diseases in 5 cases. Of the 42 cases of ulcerative keratitis, the presence of bacteria, fungi, and Acanthamoeba organisms was excluded in 33 instances (79%). Organisms observed in 9 (21%) of the 42 ulcerative cases included 4 with bacteria, 3 with fungi, and 1 each with Acanthamoeba organisms and virus.     

Slit-lamp exophthalmometry,a novel technique

Purpose

Exophthalmometry is clinically important for diagnoses, follow-up, and treatment decision-making. Through the years, several drawbacks and sources of error have been described when using Hertel and other exophthalmometers.

Methods

We describe a simple method of non-touch slit-lamp exophthalmometry. Comparing the results between Hertel and slit-lamp exophthalmometry on 60 patients with proptosis showed no statistically significant differences in the two methods.

Results

A total of 60 consecutive patients with proptosis were included. Thirty-six cases (60 %) were women. Their mean age was 55.6?±?16.4 (median 57.5, range 20–87) years. Only 5 % of the measurements had more than 2 mm difference between the two techniques. There were no significant differences in the measurements between the two methods. Intra-correlation coefficient is 0.96 for right side and 0.956 for lest side. The Bland–Altman plot revealed good agreement.

Conclusions

Slit-lamp exophthalmometry offers a simple, easily available, and reliable non-touch technique that does not require an exophthalmometer.     

Conjunctival melanoma,a retrospective study

During the period 1954 to 1974 inclusive, fourteen patients with melanoma of the conjunctiva were observed in the Department of Ophthalmology, University of Amsterdam. Frequency, etiology and treatment are discussed. No statistically proven conclusions may be drawn from this investigation; not at any rate, in regard to the treatment due to lack of homogeneity of the approaches used in recent years.