ABSTRACT
· AIM: To search an easy and simple way for intraocular implantation after the eye evisceration.· METHODS: Fifteen healthy New Zealand rabbits were divided into 5 groups according to the sacrifice time, and each group included 3 rabbits; the left eye received the injection of polymethyl methacrylate (PMMA) bone cement (2g per mL), while the right eye served as control. Under general anesthetia, a 3mm incision was made on the sclera,and the eye contents and pigment tissues were extruded out with fingers. Then, PMMA bone cement (2g per ml) was injected through the scleral incision. Both the operated eye and control eye of the rabbits were enucleated and weighed,The reaction of the operated eye (macroscopically and histopathologically) was noted at frequent interval. The obtained data were then analyzed with ANOVA (SPSS11.5).· RESULTS: There was swelling of eyelids and conjunctiva at the early time after the injection, but no significant difference between the weight of the left and right eyes was noted,Histopathologic examination showed scleral and other tissues necrosis at early period, and then the tissues reaction turned into a great deal of cell proliferation and finally into extensive fibro-connective tissues. Three months after the operation,neovascularization was observed in the cornea of the operated eyes. Histopathologic examination showed formation of fibro-membrane around the intraocular implant,and disappearance of the inflammation.· CONCLUSION: The method of injecting PMMA bone cement (2g per ml) to form an intraocular implant is quite simple and economical; this method is also easy to use clinically.
ABSTRACT
Percutaneous vertebroplasty consists of the percutaneous injection of polymethylmethacrylate (PMMA) cement into a collapsed vertebral body in order to obtain pain relief and mechanically strengthen the vertebral body. This procedure is now extensively used in treating osteoporotic vertebral compression fracture. It is an efficient treatment, but it is not free of complications. Most complications after vertebroplasty are associated with PMMA leakage. Pulmonary embolism of PMMA is rare, but this can occur when there is a failure to recognize venous migration of cement early during the procedure. We encountered a case of a patient with asymptomatic pulmonary embolism because of PMMA after percutaneous vertebroplasty. Chest X-ray and CT scanning revealed numerous tubular branching opacities that corresponded to the pulmonary vessels at the segmental and subsegmental levels.
Subject(s)
Humans , Fractures, Compression , Polymethyl Methacrylate , Pulmonary Embolism , Thorax , Tomography, X-Ray Computed , VertebroplastyABSTRACT
Study on the Potential of Hydroxapatite Based Bioactive Bone Cement PURPOSE: The purpose of this study is to propose a new bioactive bone cement (BBC) composed of bone powder (hydroxyapatite; HA), chitosan powder, and currently available polymethylmethacrylate (PMMA) bone cement for use in orthopaedic surgeries such as vertebroplasty or bone filler. MATERIALS AND METHODS: Three types of proposed BBCs and a currently available commercial PMMA were tested. In vitro studies the surface morphology, chemical composition, changes in pH value along the time, exothermic temperatures, intrusion and cellular responses were investigated. SEM, radiological and histological examinations were performed in animal studies. RESULTS: The major components of BBCs were C, O, Ca, P, Cl, Si, S, Ba and Mg. The pH values in BBCs decreased after 1 day, however they eventually reached 7.2-7.4. The water absorbency, weight loss, and porosity in BBCs increased more than PMMA more than during degradation (p<0.05). However, the compressive Young's moduli and ultimate compressive strength (UCS) of BBCs were lower than those of PMMA (<0.05). The exothermic temperatures of the BBCs were considerably lower than that of PMMA (p<0.05). In view of setting time, it takes relatively longer for BBCII and III to be solidified than PMMA (p<0.05). The intrusion tests showed that the BBCs were more intrusive than PMMA (p<0.05). The cell proliferation test on BBCII showed that the BBCII was more preferable than the PMMA. No cytotoxic characteristics were found in all BBCs. In the animal test, BBC II was more biocompatible as well as osteoconductible than the PMMA. CONCLUSION: The results of in vitro and animal studies indicated that the proposed BBCs have a potential of clinical application as replacement of the current PMMA bone cements.