Visual outcome and prognostic factors after magnetic extraction of posterior segment foreign bodies in 40 cases

Abstract

Aims-To evaluate the clinical features as well as the visual and anatomical outcome in eyes with magnetic posterior segment foreign bodies, to identify prognostic factors after removal using an electromagnet. Methods-The records of 40 patients with posterior segment foreign bodies were retrospectively reviewed for 6 years (1989-94). Post-traumatic cataracts and secondary retinal detachments were treated using conventional surgical techniques. Pars plana vitrectomy was used only for late complications. The mean follow up was 30 months (6-71). Clinical factors were studied using univariate analysis. Results-The most common findings before treatment of these 40 eyes were lens wound, hyphaema, vitreous haemorrhage, and retinal impairment. The foreign body was in the vitreous (85%) or minimally embedded in the retina (15%). Initial visual acuity was worse or equal to 20/40 in 70% of the cases. Subsequent to surgical treatment, a cataract was reported in 60% of the patients. Postoperative complications included retinal detachment (15%) and phthysis (5%). The prognosis was worse in cases with intraocular foreign body of largest diameter >3 mm, an initial visual acuity less than 20/200, or the presence of post-traumatic retinal detachment. Presence of initial intravitreous haemorrhage, hyphaema, or intraocular tissue prolapse did not appear to aVect the prognosis. Conclusion-The long term visual acuity results indicated that wound repair associated with conventional magnet extraction in an emergency is a viable treatment for posterior segment magnetic foreign bodies in this selected group. At the time of diagnosis, size of foreign body (<3 mm) and initial visual acuity >20/200 were predictors of good visual outcome after primary magnetic extraction. (Br J Ophthalmol 1998;82:801-806)

Surveillance of intraocular foreign bodies in the UK

“…11 Other authors have suggested that the external approach be restricted to cases with small (o3 mm) foreign bodies located within the vitreous or minimally embedded in the retina. 13 Pars plana vitrectomy has been recommended in the case of foreign bodies that are poorly visualised (owing to cataract or vitreous haemorrhage) and that are encapsulated in the retina, and in patients with concurrent intraocular damage (such as retinal detachment) or in whom endophthalmitis is suspected. 10 A retrospective study of external vs internal approach found no statistically significant difference in visual outcome and suggested that the external approach remained a reasonable option in selected cases.…”

“…Many of these factors have previously been reported, [6][7][8]10,13,14 and indicate that severe initial damage is strongly predictive of poor visual outcome. Interestingly, removal of IOFB within 24 h of presentation, RAPD in injured eye at presentation, and IOFB involving the posterior segment were not found to be significant factors for a poor visual outcome.…”

“…These include large diameter of IOFB, poor visual acuity on presentation, relative afferent pupil defect (RAPD) on presentation, corneoscleral entry wound, uveal prolapse, vitreous haemorrhage, and presence of a secondary retinal detachment. [6][7][8]10,13,14 The study aimed to determine whether the final visual outcome had improved compared to previous reports and whether previously identified prognostic factors remained predictive of a poor outcome.…”

Lawn mower injuries as a cause of serious visual acuity impairment – Case reports

“…Of the 140 patients identified, 114 (81%]. Overall, 5-31% patients have a final visual acuity of less than 3/60, with an increasing number of more successful operations corresponding with the advances in vitreoretinal surgery [6,7,9London. Patients who underwent a primary surgical repair and removal of a posterior segment IOFB were identified using a hospital database.…”

Comparison of Domestic and War Ocular Injuries during the Lebanese Civil War

“…In order to achieve success, it was necessary to abandon perfectionist methods and adapt to locally available facilities. Magnetic IOFB removal via an electric magnet remains a viable option in domestic injuries [27] and ideal in war injuries when one is constrained with shortage of supplies and lack of vitreoretinal surgeons. The relatively favorable long-term visual acuity results in our review indicate that wound repair associated with conventional magnet extraction in an emergency is a viable treatment for posterior segment magnetic foreign bodies.…”