OCULAR AND ORBITAL TRAUMA FROM WATER BALLOON SLINGSHOTS - A CLINICAL,EPIDEMIOLOGIC, AND EXPERIMENTAL-STUDY

Purpose: The authors report the findings of 17 patients with ophthalmi c injuries produced by launched water balloons; they determine water b alloon kinetic energies in experimental and theoretical studies. Metho ds: Six case summaries are presented; one case report was retrieved fr om the literature; ten injuries were reported to the Consumer Product Safety Commission. Energies were determined by field trials and calcul ations. Results: Injuries included periorbital edema and ecchymoses, o rbital contusions and hematomas, maxillary sinus hematomas, facial hyp esthesia, eyelid lacerations, subconjunctival hemorrhages, corneal ede ma and abrasions, hyphemas, traumatic iritis, iris sphincter ruptures, iris atrophy, angle recession, iridodialysis, traumatic cataract, vit reous hemorrhages, retinal hemorrhages, macular hole formation, optic atrophy, and bony orbital wall fractures. Epidemiologic analysis revea led that children and young adults, more often males, were injured, mo st commonly in the warm weather months. In field trials, maximum water balloon velocities ranged from 38 to 41 m/sec (85-92 mph) with kineti c energies from 176 to 245 joules; by calculation, maximum velocities ranged from 42 to 54 m/sec (95-121 mph) with kinetic energies from 141 to 232 joules, In a field demonstration, a slingshot-launched water b alloon exploded a watermelon. Conclusion: Energies are comparable to o r greater than those experienced with a variety of common objects, inc luding some rifle bullets that are known to cause serious ophthalmic i njuries. These energies are far in excess of those required to perfora te a cornea, rupture a globe, or fracture the bony orbit. This study d emonstrates the serious and potentially vision- and life-threatening i njuries inflicted by these ''toys.''