Mordechai Rosner

The Association Between Cigarette Smoking and Ocular Diseases

Tobacco smoke is composed of as many as 4,000 active compounds, most of them toxic on either acute or long-term exposure. Many of them are also poisonous to ocular tissues, affecting the eye mainly through ischemic or oxidative mechanisms. The list of ophthalmologic disorders associated with cigarette smoking continues to grow. Most chronic ocular diseases, with the possible exception of diabetic retinopathy and primary open-angle glaucoma, appear to be associated with smoking. Both cataract development and age-related macular degeneration, the leading causes of severe visual impairment and blindness, are directly accelerated by smoking. Other common ocular disorders, such as retinal ischemia, anterior ischemic optic neuropathy, and Graves ophthalmopathy, are also significantly linked to this harmful habit. Tobacco smoking is the direct cause of tobacco-alcohol amblyopia, a once common but now rare disease characterized by severe visual loss, which is probably a result of toxic optic nerve damage. Cigarette smoking is highly irritating to the conjunctival mucosa, also affecting the eyes of nonsmokers by passive exposure (secondhand smoking). The dangerous effects of smoking are transmitted through the placenta, and offspring of smoking mothers are prone to develop strabismus. Efforts should be directed toward augmenting the campaign against tobacco smoking by adding the increased risk of blindness to the better-known arguments against smoking. We should urge our patients to quit smoking, and we must make them keenly aware of the afflictions that can develop when smoke gets in our eyes.

Temporal parameters of low energy laser irradiation for optimal delay of post-traumatic degeneration of rat optic nerve

Compression injury of a central nerve results in its degeneration with irreversible loss of function due to the inability of the mammalian central nervous system (CNS) to regenerate. In contrast, the CNS of lower vertebrates has a high capacity to regenerate. Recently, low energy laser irradiation was shown to attenuate degeneration in injured CNS nerves. The optic nerves of rats were subjected to moderate crush, calibrated so that some electrophysiological activity was preserved. The nerves were then subjected to low energy laser irradiation (10.5 mW, 2 min daily) for various periods. The electrical activity of the nerves, distal to the site of injury, was determined by measuring the compound action potential at the termination of the experiment. Two weeks of irradiation begun immediately after injury and continued daily thereafter, resulted in a compound action potential which was significantly higher (mean +/- S.E.M. 1856 +/- 535 microV) than that of non-irradiated injured nerves (351 +/- 120 microV). The effect was temporary and subsided within a week. This two-week irradiation was slightly more effective than a treatment lasting one week (1406 +/- 225 microV) and was significantly more effective than 4 days of irradiation (960 +/- 133 microV). The number of treatments is therefore important. The time at which the treatment commences relative to the injury is also critical. Irradiation initiated two hours after the crush was about half as effective as immediate irradiation (810 +/- 42 microV). No apparent effect was evident when the laser was applied for the first time 5 h, or longer, after the crush.(ABSTRACT TRUNCATED AT 250 WORDS)

Patient Dissatisfaction After Functionally Successful Conjunctivodacryocystorhinostomy With Jones Tube

Conjunctivodacryocystorhinostomy with a Jones tube is an accepted procedure for the treatment of epiphora resulting from obstructed canaliculi. Because of our clinical impression that a high rate of functional success after surgery is associated with a lower rate of patient satisfaction, we analyzed the results and patient satisfaction of 121 patients who underwent conjunctivodacryocystorhinostomy with Jones tubes. The surgical success rate was 92.6% (112 of 121 patients). However, 13 of 112 patients (11.6%) whose operation was functionally successful were not satisfied and 36 of 112 patients (32%) reported having more complications than expected. The highest rate of dissatisfied patients occurred in patients 70 years of age or older (ten of 46 patients, 22%) and in patients 19 years of age or younger (one of four patients). Thus, the indication for conjunctivodacryocystorhinostomy in these age groups should be limited to exceptionally remarkable symptomatic cases. The drawbacks of the procedure should be explained to all candidates to minimize dissatisfaction resulting from unrealistic expectations.

Angiogenesis in pterygium: Morphometric and immunohistochemical study

Objective. To evaluate the role of angiogenesis in the pathogenesis of pterygium by comparing the expression of von-Willebrand factor (vWF) and vascular endothelial growth factor (VEGF) in pterygium, and in normal superior bulbar conjunctiva. Methods. 23 human samples from pterygium and the superior bulbar conjunctiva were stained using rabbit anti-vWF and anti-VEGF antibodies. The density of vWF and VEGF positive vessels, VEGF staining intensity and the number of VEGF positive stromal, epithelial and vascular endothelial cells were evaluated. Results. Pterygium specimens had higher average vWF and VEGF positive microvascular counts per high power field (P = 0.0012), higher average VEGF staining intensity scores in epithelial, stromal and endothelial cells (p < 0.0001) and higher VEGF positive cell counts (P < 0.0001) than normal conjuctiva. Conclusions. Over-expression of VEGF in pterygium tissue, together with the abundance of vWF-stained new vessels, may support previous suggestions that angiogenesis may play a role in the formation of pterygium.

Intravitreal Injections of Neurotrophic Factors Secreting Mesenchymal Stem Cells Are Neuroprotective in Rat Eyes following Optic Nerve Transection

PURPOSE To evaluate the neuroprotective effect of intravitreal injections of neurotrophic factors secreting mesenchymal stem cells (NTF-SCs) on the survival of retinal ganglion cells (RGCs) in rat eyes after optic nerve transection (ONT). METHODS Rat and human bone marrow-derived mesenchymal stem cells (MSCs) were induced to secrete high levels of NTF. The neuroprotective effect from intravitreally injected untreated MSCs or NTF-SCs was compared with that from PBS injections using an ONT model in 146 rats. RGCs were labeled by applying rhodamine dextran to the orbital optic nerve or by injecting Fluorogold into the superior colliculus. Cell- and saline-treated eyes were compared 8 days after ONT. For tracking, MSCs and NTF-SCs were labeled with PKH26 and analyzed at 2 hours and at 10, 17, and 24 days using immunohistochemistry and RT-PCR. RESULTS Mean RGC survival at 8 days after transection increased significantly after intravitreal injections of human NTF-SCs (69% ± 3%) or of untreated human MSCs (66% ± 5%) versus PBS (46% ± 3%; P = 0.0005 and P = 0.03, respectively). In an additional set of experiments, human NTF-SCs versus PBS were significantly neuroprotective, but bone marrow-derived rat NTF-SCs were not (P = 0.001 and P = 0.1, respectively). Immunohistochemistry demonstrated that human-derived MSCs, human NTF-SCs, and rat-derived NTF-SCs survived at least 24 days after intravitreal injection. CONCLUSIONS Bone marrow-derived MSCs can deliver NTFs by intravitreal injection and can be neuroprotective after ONT. This approach might be further studied to deliver NTFs by autotransplantation in glaucomatous eyes.

Transcanalicular laser-assisted dacryocystorhinostomy

BACKGROUND AND OBJECTIVE Current techniques of laser-assisted dacryocystorhinostomy are mostly endonasal. In this report, the authors describe their technique of laser-assisted dacryocystorhinostomy performed through the canaliculi and the surgical results they achieved. PATIENTS AND METHODS Fourteen patients with nasolacrimal duct obstruction underwent transcanalicular laser-assisted dacryocystorhinostomy. The bony ostium was perforated using a fiber optic-transmitting, giant-pulse Nd:YAG laser, with an energy of 0.5 to 4 J per pulse. The total energy used to create an ostium was 18 to 34 J. A silicone tube was inserted through the canaliculi and the ostium into the nasal cavity and kept in place for 5 to 7 months. Patients were observed for 18 to 22 months. RESULTS Nine of the 14 patients (64%) reported the disappearance of epiphora following surgery. In 3 patients, no relief of epiphora was obtained. In 1 patient the operation was not completed because of severe nasal bleeding. In another, tearing began 12 months after surgery (6 months after tube removal). CONCLUSIONS Transcanalicular laser-assisted dacryocystorhinostomy is a potentially useful method for performing dacryocystorhinostomy. Technical modifications and improvements are needed to increase the success rate.

Temperature-Controlled CO2 Laser Tissue Welding of Ocular Tissues

Lasers can be used for binding tissues by welding, but the clinical application of this method has been limited by the difficulties in defining and maintaining the optimal conditions. Fiberoptic radiometry allows accurate remote temperature measurements for control of laser tissue welding. We evaluated the use of a temperature-controlled tissue welding system to close corneal and corneoscleral wounds. Eighty ex vivo bovine eyes were used for the determination of welding parameters optimal for corneal wound closure. A 4 mm central corneal cut was closed with use of a CO2 laser (600 mw, 0.9 mm spot size), with tissue temperatures ranging from 45-70 degrees C and welding time ranging from 1-30 seconds. Wound strength was measured as burst pressure of the sealed wound. The welding parameters found to cause the strongest wound binding were used to weld a limbal incision of 4 mm in 10 adult albino rabbits. The fellow eye of each animal was used as a control, and the same wound was closed with one 10/0 mersilen suture. Two animals were killed immediately after the procedure, and the eyes were sent for histologic examination. Eight rabbits were followed for 1 month. Clinical examination and refraction were done 1 day, 1 week, 2 weeks, and 1 month after the procedure. Corneal topographic evaluations were done 1 week after the procedure. After 1 month the animals were killed and the eyes were examined histologically. The optimal results of wound binding by laser welding in the enucleated bovine eyes were achieved with 55-60 degrees C and at a welding time of 12-20 seconds. At these parameters the burst pressure of corneal wounds was 70 mm Hg. All laser-welded limbal wounds in the rabbits were tightly closed at the end of procedure and during the follow-up period. The refractive results after laser welding were equal to those of the controlled suture-closed wound. Laser tissue welding combined with tissue temperature monitoring can be used to close corneal wounds.

Myopia and stature: findings in a population of 106,926 males.

We conducted a nation-wide study of the relationship of myopia with height, weight and body-mass index in order to confirm observations that myopic persons are taller than non-myopes. From a review of the data of 106,926, consecutive male military recruits aged 17 to 19 years, we found that myopia is associated neither with higher stature nor with greater weight. Persons with severe myopia were slightly shorter (172.8± 7.1 cm) and weighed less (62.6± 11.0 kg) than those with mild myopia (173.3± 6.9 cm and 63.8± 10.5 kg respectively), while the non-myopes were taller (173.7± 6.7 cm) and heavier (63.9± 10.2 kg) than the myopes (p=0.0001). The mean body-mass index was only slightly smaller among the myopes (21.1± 3.1 kg/m2) than among the non-myopes (21.2± 2.9 kg/m2, p=0.0001).

The inhibitory effect of different concentrations of topical bevacizumab on corneal neovascularization

Acta Ophthalmol. 2010: 88: 862–867

Epidemiology of retinal detachment in childhood and adolescence

The prevalence of retinal detachment during childhood and adolescence was studied in 45,000 recruits aged 17 to 19 years. History of retinal detachment was found in 13 cases (0.028%); 61.5% of these had traumatic retinal detachment, and 23.1% had high myopia without history of trauma. The age-related annual incidence of retinal detachment in patients aged ten to 19 years was calculated to be 2.9 per 100,000. The prevalence among the males was 3.7 per 10,000 and among the females 1.6 per 10,000. The difference between the sexes was not statistically significant.