Ocular injuries from liquid golf ball cores.
Tissue removed from nine new cases from 18 hours to 20 weeks after injury by a golf ball contained crystalline and other foreign material to which there was a mild inflammatory reaction followed by macrophagic activity and fibrosis. Optical and electron probe analysis showed that the crystalline material was crushed barytes containing small quantities of muscovite as is typical in natural deposits. The centres of several golf balls were shown to contain essentially identical material. By contrast with previous reports, no zinc sulphide was found. The form and frequent location of the deposits in the conjunctiva as compared with cornea and eyelid is related to the structure of these tissues. (+info)
The role of ultrasound biomicroscopy in ocular trauma.
PURPOSE: To demonstrate the usefulness of ultrasound biomicroscopy (UBM) in detecting and localizing small ocular foreign bodies. METHODS: This is a retrospective study of the records of 555 consecutive patients evaluated by UBM by the Visual Physiology Unit of the Wills Eye Hospital from August 1994 to November 1997. RESULTS: In 9 patients, a foreign body was identified. In 6 patients, the history suggested the presence of a foreign body, but one could not be detected by clinical examination. In 2 patients, the referring physicians requested UBM to determine whether or how deep a known foreign body had penetrated the globe. In 1 patient, the foreign body was not suspected clinically. In regard to other diagnostic techniques, CT failed to identify the foreign body in 1 patient. In another, contact B-scan ultrasonography failed. In a third, both CT and contact B-scan ultrasonography failed. The foreign body was intracorneal in 2 eyes, subconjunctival in 2, intrascleral in 3, and intraocular in 2. Six were nonmetallic. Two were metallic. In one case, the foreign body was lost and its composition is unknown. In 5 cases, the UBM findings altered the patient's management. CONCLUSIONS: UBM is a valuable adjunct in the evaluation of small, anteriorly located foreign body that may not be detectable by other methods. UBM may be especially useful for finding nonmetallic foreign bodies. (+info)
Long-term ultrastructural changes in human corneas after tattooing with non-metallic substances.
AIM: To investigate the ultrastructural appearance and the deposition pattern of dye particles in long term non-metallic corneal tattooing. METHODS: Two tattooed human corneas were obtained by keratoplasty. One corneal button was fixed in Karnovsky's solution and the other in Trumps' solution. Both corneas were divided and processed for conventional light (LM) and transmission electron microscopy (TEM). Five additional formalin fixed corneas with tattoos were retrieved from paraffin for TEM. The time between tattoo and removal of the corneal button/enucleation ranged from 7 to 61 years. All seven corneas were examined using a Jeol JCXA733 microprobe for wave length dispersive analysis in order to exclude any presence of metallic salts in the tattooed area. RESULTS: Histologically, clumps of brown-blackish granules were present mainly in the mid stroma, but also in anterior and partially in the posterior half of the stroma. On TEM, numerous round and oval electron dense particles were seen in the cytoplasm of keratocytes arranged as clusters or large islands. The larger particles appeared black, while the smaller particles were grey. In well fixed tissue a unit membrane was observed around these clusters. No granules were detected in the extracellular matrix. CONCLUSIONS: Keratocytes can actively ingest and retain tattooing particles of non-metallic dyes within their cell membrane for very long periods of time. (+info)
Eye injuries in children: the current picture.
AIMS: To investigate the current causes and outcomes of paediatric ocular trauma. METHODS: A prospective observational study of all children admitted to hospital with ocular trauma in Scotland over a 1 year period. RESULTS: The commonest mechanism of injury was blunt trauma, accounting for 65% of the total. 60% of the patients were admitted with a hyphaema. Injuries necessitating admission occurred most frequently at home (51%). Sporting activities were the commonest cause of injury in the 5-14 age group. There were no injuries caused by road traffic accidents or fireworks. Patients were admitted to hospital for a mean of 4.2 days (range 1-25 days). One (1%) child had an acuity in the "visually impaired" range (6/18-6/60) and one (1%) was "blind" (6/60) in the affected eye. No child was bilaterally blinded by injury and none required blind or partial sight registration. CONCLUSION: This study has shown that the incidence of eye injuries affecting children has fallen. The outcome of ocular trauma has improved significantly, and for the first time paediatric injuries appear to have a better prognosis than injuries affecting adults. (+info)
Simulation model of an eyeball based on finite element analysis on a supercomputer.
BACKGROUND/AIMS: A simulation model of the human eye was developed. It was applied to the determination of the physical and mechanical conditions of impacting foreign bodies causing intraocular foreign body (IOFB) injuries. METHODS: Modules of the Hypermesh (Altair Engineering, Tokyo, Japan) were used for solid modelling, geometric construction, and finite element mesh creation based on information obtained from cadaver eyes. The simulations were solved by a supercomputer using the finite element analysis (FEA) program PAM-CRASH (Nihon ESI, Tokyo, Japan). It was assumed that rupture occurs at a strain of 18.0% in the cornea and 6.8% in the sclera and at a stress of 9.4 MPa for both cornea and sclera. Blunt-shaped missiles were shot and set to impact on the surface of the cornea or sclera at velocities of 30 and 60 m/s, respectively. RESULTS: According to the simulation, the sizes of missile above which corneal rupture occurred at velocities of 30 and 60 m/s were 1.95 and 0.82 mm. The missile sizes causing scleral rupture were 0.95 and 0.75 mm at velocities of 30 and 60 m/s. CONCLUSIONS: These results suggest that this FEA model has potential usefulness as a simulation tool for ocular injury and it may provide useful information for developing protective measures against industrial and traffic ocular injuries. (+info)
Orbitocranial injury caused by wood.
A rare case of a patient with orbitocranial injury by a wooden foreign body is reported. Penetrating periorbital wound by a wooden stick with entry site at the right upper eyelid was related to the invasion into the temporal lobe. Fortunately, the anterior and posterior segments of eye were unharmed, but right ocular motility was markedly restricted mechanically in all directions. Forced duction test was strong positive, especially the dextroversion of the right eye. Computed tomography scan showed a well-delineated low density from the orbital wall into the temporal lobe. The wooden foreign body was subsequently removed from the orbit and the temporal lobe, through the neurosurgical frontotemporal approach. After the wooden foreign body was removed, the ocular movement of the right eye fully recovered without any intracranial or ocular complications. (+info)
Mine blast injuries: ocular and social aspects.
BACKGROUND/AIMS: Landmines have long been used in conventional warfare. These are antipersonnel mines which continue to injure people long after a ceasefire without differentiating between friend or foe, soldier or civilian, women or children. This study focuses on Afghan non-combatants engaged in mine clearing operations in Afghanistan in the aftermath of the Russo-Afghan war. The patterns and types of injuries seen are described and experiences in their management, ways, and means to prevent them, and recommendations for the rehabilitation of the affected individuals are given. METHODS: It is a retrospective and analytical study of 84 patients aged 19-56 years who sustained mine blast injuries during mine clearing operations in Afghanistan from November 1992 to January 1996. The study was carried out at a military hospital with tertiary care facilities. The patients were divided into three groups on the basis of their injuries. Group 1 required only general surgical attention, group 2 sustained only ocular injuries, while group 3 had combined ocular and general injuries. Patients in groups 2 and 3 were treated in two phases. The first phase aimed at immediate restoration of the anatomy, while restoration of function wherever possible was done in subsequent surgical procedures in the second phase. RESULTS: It was observed that 51 out of 84 patients (60.7%) had sustained ocular trauma of a variable degree as a result of the blasts. The mean age of the victims was 29 years and they were all male. A total of 91 eyes of 51 patients (89.2%) had been damaged. Bilaterality of damage was seen in 40 (78.4%) patients. Most, 34 (37.3%), eyes became totally blind (NPL). Only a few escaped with injury mild enough not to impair vision. Foreign bodies, small and multiple, were found in the majority of eyes; most, however, were found in the anterior segment, and posterior segment injuries were proportionally less. CONCLUSIONS: The prevalence of blindness caused by mine blast injuries is quite high. The resulting psychosocial trauma to the patients and their families is tremendous and has not been adequately highlighted. These injuries are a great drain on the country's resources. Enforcement of preventive measures and the use of protective gear and sophisticated equipment by the mine clearing personnel would prove to be far more economical in terms of human life as well as medical and economic resources. There is also need for greater attention towards the establishment of support groups and rehabilitation programmes for these individuals. (+info)
Two remarkable events in the field of intraocular foreign body: (1) The reversal of siderosis bulbi. (2) The spontaneous extrusion of an intraocular copper foreign body.
Two unusual events concerning intraocular foreign bodies are presented. The first patient had an occult or unsuspected intraocular foreign body. He showed iridoplegia with mydriasis, siderosis iridis, and an intraocular piece of iron lying posteriorly near the retina. The foreign body was removed and the patient regained normal iris color and pupillary activity. His vision remains 20/15 six years postoperatively dispite ensuing retinal detachment one year after removal of the foreign body. The second patient was a young boy injured by a blasting cap explosion. He lost one eye from the injury and had a piece of intraocular brass in his left eye. In spite of the development of chalcosis and a mature cataract the lens gradually shrank in the pupillary space permitting a clear aphakic area and 20/25 vision. The brass fragment migrated forward and inferiorly and was finally extruded under the conjunctiva five years later, where it was removed and chemically analyzed by x-ray diffraction. (+info)