Eleven years' experience with retinopathy of prematurity: visual results and contribution of cryoablation.

We report our 11 years' experience of cryotherapy for retinopathy of prematurity (ROP). Charts of 624 infants weighing under 1250 g who were admitted to our Neonatal Intensive Care Unit during 1977-87 were reviewed. Three hundred and eighty nine babies survived, and the total ROP prevalence was 57.5%. Cryotherapy was applied to 35%. Only one case (0.25%) of blindness was detected, and four babies (1%) had a final visual acuity of less than 20/200 in one eye. The complication rate following cryoablation was very low.

Effect of partial cryoablation on retinopathy of prematurity.

Cryotherapy has been shown to be an effective treatment for retinopathy of prematurity stage 3. It is said to reduce the unfavourable outcome of the disease by 50%. The accepted method of therapy includes ablation of the whole avascular retina from the ridge to the ora serrata. This is achieved by two to three rows of cryoapplications. When 360 degrees cryo treatment is performed, it requires 52 cryo applications. We present our method of cryotherapy which involves only one row of cryoapplications in the avascular retina anterior to the fibrovascular ridge. An average of 25-30 cryoapplications was required for a 360 degrees treatment. The anatomical results in 23 babies are presented. Complete regression of active retinopathy was found in all.

Static and kinetic perimetry results of krypton red laser treatment for macular edema complicating branch vein occlusion.

Twenty patients with clinical and angiographic evidence of recent branch vein occlusion complicated by macular edema were assigned to receive krypton red laser treatment if their macular edema lasted more than three months. Visual acuity, static and kinetic perimetry, fundus photography, and fluorescein angiography were evaluated before treatment and at two-month intervals thereafter. Visual acuity improved by two lines one year after treatment in 65% of patients. Each of these patients had a complete perifoveal capillary arcade. Static perimetry results correlated well with visual acuity, and a significant threshold improvement was detected in these patients. Visual-acuity results and static and kinetic perimetry findings are presented. The rationale for selection of the krypton red wavelength (647 nm) is discussed.

The treatment of foveal central serous choroidopathy by krypton red laser.

We present 24 patients with recent foveal central serous choroidopathy. Only those in whom the leakage site was located within a radius of 250 microns from the foveal center were included in this study. All patients were treated with the krypton red laser (647 nm) within a week of the clinical diagnosis. At the end of the follow-up, 70.8% of the patients had a visual acuity of 6/8.5 or better, and an overall visual improvement was found in 83.3%. In 90% of the patients whose vision improved, significant absorption of subretinal fluid was seen within three weeks and in 10% within four weeks. No evidence of any macular pathology complicating the laser treatment was found at the end of the follow-up period of at least 36 months.

Nasal versus temporal preretinal vasoproliferation in retinopathy of prematurity.

Nasal preretinal neovascularisations have been observed to develop at least two weeks earlier than those on the temporal side in more than a third of premature babies with retinopathy of prematurity (ROP) stage 3, weighing between 690 and 1030 g. All these babies were assigned for cryotherapy. This interesting observation is discussed in relation to retinal vascular development and the pathogenesis of ROP.

Radiation retinopathy treated with the krypton red laser.

We present two cases of radiation retinopathy treated with the krypton red laser (647 nm). The macular edema and exudates resolved completely after treatment, but visual acuity improved only partially due to the development of a lamellar macular hole. The rationale for laser therapy and the selection of the red wavelength are discussed.

Borderline spindle cell nevus of the ciliary body as a second primary melanoma--a clinicopathologic case.

We present the case of a 22-year-old woman who underwent surgical excision of a malignant melanoma of the skin three years previously and whom we saw for a pigmented tumor of the iridocorneal angle of her right eye associated with end-stage secondary glaucoma. After the clinical diagnosis of ring melanoma, she underwent enucleation of the eye. The pathologic examination showed a lesion predominantly appearing as a nevus with areas of borderline melanoma formation. The main features of this case were the young age of the patient, the predominant nevoid appearance of this diffuse ciliary body tumor with ring configuration, and the fact that it is a second primary melanoma in such a young patient.

Cytologic and biochemical examination of the subretinal fluid in diagnosis of Coats' disease.

Two babies presenting with unilateral leukocoria were found to have total retinal detachment in one eye, associated with subretinal yellowish-white deposits. As no calcification was found and subretinal fluid aspiration yielded many fat-laden macrophages without any evidence of retinoblastoma cells in addition to a high level of cholesterol, the difinitive diagnosis of Coats' disease was made. Subsequently, retinal detachment surgery and cryotherapy were performed, in an attempt to preserve the affected eye.

Threshold sensitivity tests in various ocular diseases.

The threshold sensitivity visual-field test is one of the most accurate ways to detect ocular disorders. The indications for utilization of this device in the detection and follow-up of many diseases other than glaucoma and neuro-ophthalmologic disorders can be expanded.

Postoperative refractive changes in children with congenital esotropia: a preliminary study.

A transient myopic inclination was found 2 months postoperatively in 23 children who had undergone surgery for congenital esotropia. Neither the age of the children at the time of surgery nor the length of muscle recession/resection influenced these refractive myopic changes. Early postoperative refractive correction with periodic follow-up is essential in preventing amblyopia. In 21 of the 23 children, visual acuity was 6/10 or better at last examination.

Pseudophakic and aphakic pupillary block.

Fifteen eyes of 14 patients who underwent cataract extraction surgery with or without lens implantation developed pupillary block. Six lenses were of the anterior-chamber type, two of the posterior-chamber, and four of the iris-clip Binkhorst type; three were simple aphakic eyes. Ocular hypertension was present in 12 eyes; while in three eyes, the pupillary block was detected by biomicroscopic examination. In order to relieve the block, we performed one of the following three procedures: laser (yttrium aluminum garnet (YAG), argon, or krypton) iridotomy, YAG laser photodisruption of the anterior vitreous face, or pars plana vitrectomy.

Juxtapapillary exophytic retinal capillary hemangioma treated by yellow krypton (568 nm) laser photocoagulation.

A 30-year-old man was found to have juxtapapillary exophytic capillary hemangioma complicated by circinate maculopathy and peripapillary exudative retinal detachment. The diagnosis was made from the appearance of the tumor and confirmed by fluorescein angiography. The presence of intermittent hematuria associated with a cystic kidney supported the diagnosis of von- Hippel-Lindau disease. subsequently, and attempt to treat the vascular lesion by yellow krypton (586 nm) laser photocoagulation failed to arrest the progression of the exudative retinal detachment, which finally became total.

Corneal metastatic calcification in Werner's syndrome.

We examined twin sisters with a clinical picture typical of Werner's syndrome. Both had undergone bilateral cataract extraction, one at 39 and one at 36 years of age, and had subsequently developed bilateral corneal metastatic calcification within a period of one to two years. In one twin, this keratopathy was associated with hypercalcemia. Each of the twins underwent penetrating keratoplasty in one eye, which was complicated by recurrence of metastatic calcification in a previously normal and clear corneal graft.

Visual acuity, strabismus, and amblyopia in premature babies with and without retinopathy of prematurity.

One hundred eighty-seven premature babies, 48 of whom suffered from retinopathy of prematurity (ROP), were examined. A higher incidence of strabismus was found in the group with cicatricial ROP (23% vs. 9%). Amblyopia was present in 6% of the ROP group and in only 1.4% of babies without ROP. Myopia was found in 50% of the ROP group as compared with 15% in the nonROP group. Astigmatism and anisometropia were more common in the ROP group, but hypermetropia was equally represented in both groups.

Retinopathy of prematurity.

Over the last decade major advances have been made in the understanding of the pathogenesis and evolution of retinopathy of prematurity (ROP). The increased survival of very small premature infants in modern neonatal intensive care units has led to the resurgence of this potentially blinding disease. ROP appears to be a multifactorial disease, the prevention of which is probably impossible even now, with the most accurate methods of blood gas monitoring and oxygen restriction. In addition to oxygen, there are a number of significant risk factors, such as birth weight and gestational age, ventilator hours, hyper and hypocarbia, hypoxia and acidosis, xanthine therapy and probably bright light. Current data suggest that the level of antioxidants in the immature retina is relatively low and therefore oxygen radicals which accumulate in the preterm baby's retina may play an important role in the pathogenesis of ROP. The treatment of the disease in both its "active" and "cicatricial" stages emphasizes the need for a new classification which could serve as a common international language through which results may be compared. Vitamin E was suggested in some studies to be helpful in preventing the severe stages of the disease, but its efficacy has yet to be proved. Treatment modalities such as photocoagulation, cryotherapy and vitrectomy are being tried as a means of therapy in the more advanced stages of the disease. Preliminary results of a large multicenter study support the efficacy of cryotherapy.

The effect of cryotherapy on oxygen-induced retinopathy in the newborn kitten.

Partial cryotherapy was performed in the right eye of 14 kittens with experimental oxygen-induced retinopathy, while the left eye remained untreated as a control. Subsequent funduscopic examination and histopathological studies of all kittens showed no significant difference between the treated and untreated eyes with respect to the amount of neovascular proliferation. We attribute this negative result mainly to the fact that the cryoablation of the kittens' retina was incomplete, leaving a considerable amount of residual ischemic retina.

The retinal effects of copper vapor laser exposure.

The copper vapor laser is a pulsed gas laser which emits energy in two wavelengths simultaneously: 510.6 nm (green) and 578.2 nm (yellow). Each pulse has a duration of 15 nsec, maximal energy of 3 mJ and a peak power of more than 100 kW. It is a variably high repetition rate laser, in the range between 1 kHz and more than 20 kHz. We studied its interaction with the rabbit retina, while using two different repetition rates, 4 kHz and 18 kHz. The histological analysis of the lesion produced by 4 kHz repetition rate showed undesired retinal effects, similar to those caused by other pulsed lasers. On the other hand, the histological examination of the lesion produced by the 18 kHz repetition rate showed a desired coagulation effect, limited to the outer retinal layers, and comparable to a lesion produced by a continuous wave (CW) laser.

Peripheral retinal neovascularization and rubeosis iridis after a bilateral circular buckling operation.

This report describes a young high-myopic patient who developed rubeosis iridis with peripheral retinal neovascularization one year after a circular buckling operation. Subsequently, vitreous bleeding and exudation led to traction retinal detachment which was treated successfully by anterior vitrectomy and cryopexy. It is suggested that this case represents a mild form of anterior-segment ischemia, combined with peripheral retinal ischemia.

Loss of accommodation produced by peristriate lesion in man?

We observed a bilateral accommodative paresis associated with a spontaneous parieto-occipital hematoma in a 37-year old patient. There was no clinical or computerized tomography (CT) evidence of transtentorial herniation or upper brainstem pathology. With resolution of the hematoma, accommodation returned to normal.