[Standardisation of optotypes]. / Standardizacija optotipa.

Optotypes are signs of different sizes, systematically placed on the visual acuity chart. The human eye has a spatial resolution of 1' of arc (Snellen). Optotypes in the basic row on all charts subtend 5' of arc and their detail 1' of arc, from the testing distance. The disadvantage of all classical charts is the irregular progresssion of optotype sizes in adjacent rows. This was solved by logMAR (Bailey-Lovie) chart in 1976. The chart was made with optotype sizes in steps with a constant ratio 1:1.2589 (geometric progression). This chart has become the standard for visual acuity testing worldwide. It has been recommended by the following bodies: International Council of Ophthalmology (ICO), 1984 and 2002; World Health Organisation (WHO), 2003; International Organisation for Standardisation (ISO) 1996, and Croatian Standard Institute homologised the ISO standard as nHRN EN ISO 8596:1996. For normative, medical and practical reasons it is advised that all school medicine, occupational health and ophthalmology departments adopt the logMAR charts system.

[Haemosiderosis bulbi in a patient with myelodysplastic syndrome (MDS RAEB-1)]. / Haemosiderosis bulbi kod pacijenta s mijelodisplasticnim sindromom (MDS RAEB-1).

Haemosiderosis bulbi is a degenerative condition of the eye bulb caused by the toxic effects of an intracellular accumulation of haemosiderin. Haemosiderin is a product of the decomposition of haemoglobin. The most common and severe damage takes place in the epithelial cells of the eye tissues. Haemosiderosis bulbi is a complication of the long existing haemophthalmus, the intravitreal bleeding, which is neither spontaneously resorbed nor operatively removed. The condition is characterized by the loss of light perception and the reddish colour of the intrabulbar tissues. The cause of the haemophthalmus in our patient is protracted anaemia due to pre-existing myelodysplastic syndrome (MDS RAEB-1).

[Clinical approach to normal intraocular pressure glaucoma]. / Klinicki pristup glaukomu normalnoga tlaka.

Normal intraocular pressure (IOP) glaucoma is a clinical condition characterized by pathologic optic nerve excavation and visual field impairment, defined as optic neuropathy with certain features of a disease known as glaucoma. Glaucomatous optic nerve lesion is characterized by optic disk excavation or depression, however, this feature may greatly vary. The level of IOP is considered only one of the multiple risk factors involved in the disease development. In normal IOP glaucoma, papillary lesions and visual field impairments may differ from those occurring in primary open-angle glaucoma. In modern ophthalmology, the terminology has been modified, so the term low IOP glaucoma has been replaced by the term normal IOP glaucoma. It is now believed that various factors play a role in the development of glaucomatous optic neuropathy in normal IOP glaucoma and show variable interference depending on IOP level. Additional studies are needed to define these interactions and their impact on the mechanism of glaucomatous excavation. This will hopefully pave the way to new therapeutic approaches and help in clinical decisions concerning the prognosis and treatment of individual patients.

A contribution to the surgery of the trachomatous entropion and trichiasis.

Although the WHO document WHO/PBL/93.29 recommends the bilamellar tarsal rotation operation for trachomatous entropion, we will describe another operation that has proved to be very reliable. It is a combined method, consisting of the modified tarsal wedge resection and the eversion splinting-grey line incision. A possible additional correction of the grey line incision on the first postoperative day improves the results. A total of 708 eyes with moderate trachomatous entropion and major trichiasis underwent this surgery, but only 508 of these were followed up during a 6-month period. The rate of failed operations, which consisted of incomplete closure of the lids or more than two inverted lashes remaining, was 6.9%.