[Retinopathy of prematurity--functional and structural outcome in children treated with diode laser photocoagulation]. / Retinopatija prematuriteta--funkcionalni i strukturni ishod u djece lijecene laserskom fotokoagulacijom.

AIM: To present the long-term structural and functional outcome of children treated with diode laser for retinopathy of prematurity. PATIENTS AND METHODS: A total of six premature babies (12 eyes) in whom diode laser treatment was performed for acute retinopathy were followed up. The mean birth weight was 1185.0 +/- 309.6 g and mean gestational age was 28.5 +/- 1.87 weeks. Long term follow-up (18 to 41 months) included retinal examination, refractive status of the eye, and orthoptic evaluation: strabismus, amblyopia and nystagmus assessment. RESULTS: Unfavorable structural outcome was detected in five eyes of six children (5/12 eyes, 41.7%). If only the eyes in no higher than threshold stage (3+) according to surgery records were taken in consideration (6/12 eyes), therapy resulted in favorable structural outcome in all six (100%) eyes. The mean spherical equivalent refractive error was -2.27 +/- 2.03 D (range -6.0 to +0.50 D). Profound amblyopia of one eye was found in five of six study children, and was invariably accompanied by heterotropia of the amblyopic eye: deviation in eso direction in three cases, and exodeviation and hypertropia in one case each. Nystagmus was present in four of six (66.6%) patients. All six children used vision as a dominant sense in space orientation and communication. CONCLUSION: Diode laser therapy is a successful method in stopping and reversing the clinical course of severe retinopathy of prematurity, however only if timely implemented. The availability of this treatment modality in Croatia would significantly improve the structural and functional outcome of children with retinopathy.

Foveation period and waveforms of congenital ocular nystagmus.

Normal visual acuity requires a stationary retinal image on the fovea. If fixation instabilities cause movement of the retinal image across the fovea for a few degrees, visual acuity is diminished. Nystagmus as the fixation instability, consequently, may impair vision. Period of foveation is the area in the wave form, i.e. a brief period of time when the eye is still and is pointed at the object of regard. At this period eye velocity is at a minimum and visual acuity is the best. In the children with congenital ocular nystagmus, using usual clinical equipment (TC 1.0 and TC 0.3 s), was performed electronystagmography (ENG) and analysis of the obtained nystagmus waveforms. In the some patients visual acuity was also examined. The ENG records were classified according to Dell'Osso criteria for waveforms. The findings of jerk nystagmus with extended foveation (J(EF)) and of bidirectional jerk nystagmus (BDJ) were singled out. Foveation time, measured in these weveforms was compared with the visual acuity. Visual acuity was better in the jerk nystafmus weveforms with extended foveation period (J(EF)) than in bidirectional jerk nystagmus with shorter foveation time.