11/155. Amniotic membrane transplantation for acute chemical or thermal burns. PURPOSE: To determine whether preserved human amniotic membrane (AM) can be used to treat ocular burns in the acute stage. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Thirteen eyes from 11 patients with acute burns, 10 eyes with chemical burns and 3 with thermal burns of grades II-III (7 eyes) and grade IV (6 eyes), treated at 7 different facilities. methods: patients received amniotic membrane transplantation (AMT) within 2 weeks after the injury. MAIN OUTCOME MEASURES: Integrity of ocular surface epithelium and visual acuity during 9 months of follow-up. RESULTS: Ten patients were male and one patient was female; most were young (38.2 /- 10.6 years). For a follow-up of 8.8 4.7 months, 11 of 13 eyes (84.63%) showed epithelialization within 2 to 5 weeks (23.7 /- 9.8 days), and final visual acuity improved > or = 6 lines (6 eyes), 4 to 5 lines (2 eyes), and 1 to 3 lines (2 eyes); only one eye experienced a symblepharon. Eyes with burns of grade II to III showed more visual improvement (7.3 /- 3 lines) than those with burns of grade IV (2.3 /- 3.0 lines; P < 0.05, unpaired t test). In the group with grade II or III burns, none had limbal stem cell deficiency. All eyes in the group with grade IV burns did experience limbal stem cell deficiency. CONCLUSIONS: Amniotic membrane transplantation is effective in promoting re-epithelialization and reducing inflammation, thus preventing scarring sequelae in the late stage. In mild to moderate burns, AMT alone rapidly restores both corneal and conjunctival surfaces. In severe burns, however, it restores the conjunctival ocular surface without debilitating symblepharon and reduces limbal stromal inflammation, but does not prevent limbal stem cell deficiency, which requires further limbal stem cell transplantation. These results underscore the importance of immediate intervention in the acute stage of eyes with severely damaged ocular surface. Further prospective randomized studies including a control group are required to determine the effectiveness of AMT in acute chemical and thermal burns of the eye. ( info) |
12/155. zinc burns: a rare burn injury. A patient was presented with significant burns resulting from a workplace accident in a zinc production unit. This occurred as a result of the spontaneous combustion of zinc bleed under high pressure. The patient sustained burns to the face, body, and hands and suffered significant injury to the left cornea. Computed imaging revealed solid particles in the ethmoid sinus and also in the right nasal fossa, dissecting the right lacrimal duct. Photographic documentation is presented. This injury was potentially preventable and resulted from poor observance of safety procedures. ( info) |
13/155. Inadvertent topical exposure to isocyanates caused damage to the entire eyeball. isocyanates are part of a group of important chemicals necessary in the production of adhesives, synthetic rubbers, and a variety of plastics. They are known to have minimal toxic effects when administered locally. However, we experienced a case of damage involving the entire eyeball in a person who accidentally exposed his eye to isocyanates. The patient presented with inflamed conjunctiva, and shrunken cornea and sclera, with focal atrophic changes in the iris. The lens and vitreous were opacified. After removal of the lens and vitreous, there were large areas of atrophic retina and areas of retinal necrosis with holes. We found that locally absorbed isocyanates can cause damage to the entire eyeball. Therefore, we recommend that if there is any evidence of isocyanate penetration, early vitrectomy should be performed to help in determining the extent of retina damage and to decrease the amount of toxic substance in the vitreous. ( info) |
14/155. Autologous limbal transplantation in unilateral chemical burns. PURPOSE: To describe the results of autologous limbal transplantation in the treatment of unilateral chemical burns. patients AND methods: Two patients, a 40-year-old male (case 1) and a 35-year-old male (case 2), experienced grade III chemical trauma and were treated with autologous limbal grafting (case 1) after a postaccident period of 3 and 9 months, respectively. Change in visual acuity, epithelial healing time and postsurgical topography healing patterns were documented. RESULTS: Snellen visual acuity improved from 0.1 to 1.0 in both cases. Epithelial healing time for cases 1 and 2 were 4 and 2 weeks, respectively. corneal topography of case 1 showed an induced inferior steepness type of asymmetrical astigmatism in the graft area. Serial topography showed no induced astigmatism in the donor eyes. CONCLUSION: Autologous limbal grafting is an adequate treatment for selected cases of unilateral chemical burns and facilitates rapid improvement in visual function. Early limbal grafting in case 1 resulted in rapid re-epithelialization and prevention of complications. ( info) |
15/155. Amniotic membrane transplantation in acute chemical and thermal injury. PURPOSE: To present a case of chemical injury and a case of thermal injury treated by amniotic membrane transplantation in acute phase. methods: case reports. An eye with sodium hydroxide injury, opaque cornea, and limbal ischemia of more than 180 degrees and an eye with hot tea injury, opaque cornea, stromal edema, and scarring were treated by amniotic membrane transplantation within the first few weeks of injury. RESULTS: In the eye with sodium hydroxide injury, 4 months after amniotic membrane transplantation, the ocular surface is stable, superficial corneal scarring with vascularization is present, and visual acuity is 20/25. In the eye with thermal injury, 6 months after amniotic membrane transplantation, the ocular surface is stable, but there is superficial scarring and vascularization, and visual acuity is 20/20. CONCLUSIONS: Amniotic membrane transplantation can be considered in chemical injury with severe limbal ischemia and in severe thermal injury in acute phase. Long-term studies are warranted to evaluate further the efficacy of amniotic membrane transplantation in these clinical situations. ( info) |
16/155. Burn scar malignancies of the eyelids. PURPOSE: To study the clinicopathologic characteristics and treatment of eyelid carcinomas developing in thermal burn scars. methods: A review of eight cases of eyelid burn scar malignancies: two from our own experience and six from published reports. RESULTS: Reported cases of burn scar malignancy of the eyelid are short-latency basal cell carcinomas. All carcinomas arose from small superficial burns. These potentially aggressive tumors respond well to local excision. CONCLUSION: As with other areas of the body, eyelid burn scars may undergo neoplastic degeneration. These carcinomas are predominately short latency basal cell carcinomas, rather than long-latency squamous cell carcinomas that are more common elsewhere in the body, including the head and neck region. Clinicians should be diligent in the long-term surveillance of all eyelid burns. ( info) |
17/155. Development of a newly designed double-fixed Seoul-type keratoprosthesis. OBJECTIVE: To develop a newly designed double-fixed keratoprosthesis (Seoul-type keratoprosthesis [S-KPro]) and to assess its mechanical stability and biocompatibility. methods: Twenty-five rabbits were divided into 4 groups by fixation technique, amniotic membrane (AM) implantation, and skirt material. The eyes were studied with the use of slitlamp, light, and electron microscopy. Stress testing was performed. In addition, 2 human subjects underwent S-KPro implantation. Best-corrected visual acuity was checked, and ophthalmic examination was performed. RESULTS: The average retention period of the group receiving double-fixated polyurethane-S-KPro with AM was longer (>24 weeks) than that of the others. Fibroblast invasions were found in polyurethane pores but not in polytetrafluoroethylene (Gore-Tex) pores on light microscopy. The minimal pressure that induced aqueous leakage was greater than 250 mm Hg in all of the tested eyes. Two human subjects have maintained a good postoperative condition for 18 and 8 months. CONCLUSIONS: The double-fixation technique of applied S-KPro and AM appears to be helpful in improving the stability of the keratoprosthesis. Polyurethane with relatively large pore size (40 microm) may be used successfully as a material for the keratoprosthesis skirt. CLINICAL RELEVANCE: Our results may be important for improving the clinical outcome of keratoprosthesis. ( info) |
18/155. corneal perforation with extrusion of lens in a burn patient. The incidence of ophthalmologic injuries has been reported to be between 20 and 25% in all the burn patients. As most of the eye injuries are associated with severe burns, attention is often directed towards the life-threatening events and eye injuries may be overlooked and undertreated. This case report presents a patient who had 40% flame burn and had recently been transferred from another hospital. He was examined by an ophthalmologist at the referring hospital and it was documented that both of his eyes were normal. He was transferred into the burns Unit at the Prince of wales Hospital 8 h later. Unfortunately, all the attention was directed to save his life and it was not until post-burn day 11 that he was found to have right corneal ulceration. Despite vigorous ophthalmologic treatment, the cornea perforated 2 days later with subsequent extrusion of the lens. In view of his grave prognosis with multi-organ failure, he was treated conservatively and he died the following day. It is mandatory to refer patients with facial burns to the ophthalmologist for ocular examination. We recommend that serial eye examinations should be carried out in burn patients who are unconscious or intubated for ventilatory support even if the initial ophthalmologic examinations are normal as the potential risk of serious ocular injuries are high in this particular group of patients. ( info) |
19/155. Failure of amniotic membrane transplantation in the treatment of acute ocular burns. AIM: To report the failure of amniotic membrane transplantation (AMT) for ocular surface reconstruction in patients with severe acute chemical and thermal burns. methods: Four eyes of three patients who suffered severe chemical (n=3) and thermal (n=1) burns were studied. The aim of AMT was to prevent symblepharon formation, promote conjunctival regeneration, inhibit corneal melting by promoting epithelialisation, and to protect the ocular surface while associated lid burns were treated. AMT was used to cover the entire ocular surface of all the severely burnt and ischaemic eyes, 2-3 weeks after the injury. Where indicated, AMT was repeated by itself or in combination with other procedures in all patients. RESULTS: Three of the four eyes developed symblepharon and progressive corneal melt requiring urgent tectonic keratoplasty. All four eyes had persistent epithelial defects. Less than 25% of conjunctival regeneration occurred in three eyes. Two eyes autoeviscerated, one patient underwent lid sparing exenteration for a painful blind eye and one eye became phthysical. CONCLUSIONS: AMT did not help to restore the ocular surface or preserve the integrity of the eye in all our patients with severe acute burns, when used by itself or in combination with other surgical procedures. This reflects the extreme severity of the ocular burns in these patients and, in turn, draws attention to the fact that the current classification system does not adequately reflect such severity. In the current system such burns would be grouped under grade IV injuries to the eye (more than 50% limbal ischaemia). The prognosis of patients with 100% limbal ischaemia is much worse than patients with just over 50% limbal ischaemia. This inadequacy of the classification system probably also explains the difference between outcomes of management of grade IV burns (with AMT) in this series, compared with others. ( info) |
| Hexafluorine is an amphoteric, hypertonic, polyvalent compound for decontaminating hydrofluoric acid (HF) eye and skin splashes. In a German metallurgy facility during the period of 1994-1998, all eye or skin splashes with 40% HF alone or with a 6% HF/15% HNO3 mixture were initially decontaminated with Hexafluorine within 2 min following the splash at the accident site by the victims themselves or co-workers who witnessed the accident. Eleven workers using 40% HF or a 6% HF/15% HNO3 mixture sustained eye (2 cases) or skin (10 cases) splashes (1 combined) during 1994-1998. Hexafluorine was used within 2 min, and a second Hexafluorine decontamination was done on arrival at the plant infirmary. No further medical or surgical treatment was needed, no workers developed chemical burns, and none lost work time. These II cases demonstrate the efficacy of Hexafluorine in decontaminating HF or combined HF/HNO3 splashes. ( info) |