Iatrogenic crystalline lens injury during intravitreal injection of triamcinolone acetonide: A report of two cases.

BACKGROUND: Intravitreal injection has become an efficient approach for delivering drugs at therapeutic levels to the posterior segment in retinal diseases. However, the increased frequency and number of intravitreal injections have raised concerns about their side effects. As manipulation during surgery is relatively simple, details of the procedure are easily overlooked. Iatrogenic crystalline lens injury is a rare complication caused by improper manipulation during surgical procedures. We report two cases of crystalline lens injury during intravitreal injection of triamcinolone acetonide (TA) with the hope of providing an insight into this treatment. CASE SUMMARY: Case 1 was a 62-year-old woman with macular edema caused by central retinal vein occlusion in her right eye, and Case 2 was a 65-year-old man with macular edema caused by branch retinal vein occlusion in his right eye. In view of the patients' condition and economic constraints, an intravitreal injection of TA was administered. Due to inappropriate manipulation during surgery, the lens was injured. The site of lens injury and clinical manifestations were different in the two cases. Symptomatic treatment and continuous follow-up were carried out. The therapeutic effect following phacoemulsification of the cataract was satisfactory. CONCLUSION: Well-defined surgical incision under proper anesthesia, sufficient patient information and proficient anatomical skills of the physician are mandatory to prevent this rare adverse event. Careful and meticulous phacoemulsification of the cataract is suggested.

Effects of phacoemulsification on intraocular pressure and anterior chamber depth.

The aim of this study was to investigate the effects of phacoemulsification with intraocular lens (IOL) implantation on intraocular pressure (IOP) and anterior chamber depth (ACD) in patients with cataract or cataract associated with primary angle closure (PAC). A total of 361 patients (481 affected eyes) with senile cataract (cataract group) and 44 patients (52 affected eyes) with cataract associated with PAC (cataract with PAC group) underwent phacoemulsification with IOL implantation from July 2005 to May 2007 and were followed up for 3 to 25 months. There was a significant difference between pre-operative and post-operative IOPs (t=9.270, P<0.01) in the cataract group and in the cataract with PAC group (t=3.29, P<0.01). No significant differences were identified in pre-operative IOP (t=-2.437, P>0.05) and the IOP three months after surgery (t=2.154, P>0.05) between the two groups. There was a significant difference between the pre-operative and post-operative ACDs (t=7.781, P<0.01) in the cataract group and in the cataract with PAC group (t=4.528, P<0.01). A significant difference in ACD between the two groups (t=8.325, P<0.01) existed prior to surgery but following surgery, the ACDs of the two groups were not significantly different (t=2.86, P>0.05). Phacoemulsification with IOL implantation has IOP-lowering effects on cataract and cataract with PAC patients. The International Society of Geography and Epidemiology of Ophthalmology classification method for angle closure glaucoma was adopted in our study. Furhter studies are required to prove the safety and mechanism of lowering IOP impact of phacoemulsifation towards PAC glaucoma (PACG).

[Long-term clinical observation of an accommodative 1CU after implantation].

OBJECTIVE: To evaluate the clinical effectiveness and accommodative range after implanting the 1CU. METHODS: It was a prospective case series study. From March in 2004 to December in 2007, 23 cases (28 eyes) had phacoemulsification and implantation of 1CU (HumanOptics). Naked and best corrected distant acuity, Naked acuity at 35 cm and best corrected near, the amplitude of accommodation measured with subjective and objective techniques and the change in the anterior chamber depth were measured at 3-6 months, 18-24 months and over 36 months after surgery. RESULTS: After implantation, the 1CU had good centered and stable and no IOL-specific complications. Naked distant acuity of the three groups are 0.84+/-0.23, 0.81+/-0.19 and 0.78+/-0.17, between them there are no significantly statistical differences (F=0.759, P>0.05). The best corrected distant acuity of the three groups were 0.97+/-0.13, 0.99+/-0.17 and 1.00+/-0.17, between them there are no significantly statistical differences (F=0.17, P>0.05). The near acuity at 35 cm was 0.66+/-0.24, 0.52+/-0.14 and 0.47+/-0.12, between them there are significantly statistical differences (F=9.312, P<0.01). The best corrected near acuity were 0.97+/-0.13, 0.94+/-0.22 and 0.90+/-0.21, between them there are no significantly statistical differences (F=0.915, P>0.05). The accommodative range measured with subjective were 0.89+/-0.34, 0.72+/-0.17 and 0.56+/-0.16, between them there are significantly statistical differences (F=13.43, P<0.01). The accommodative range measured with objective were 3.58+/-0.54, 3.01+/-0.89 and 2.50+/-0.54, between them there were significantly statistical differences (F=17.886, P<0.01). The anterior chamber depth measured by application of 2% pilocarpine eyedrops were 0.88+/-0.40, 0.54+/-0.23 and 0.33+/-0.20, between them there were significantly statistical differences (F=26.589, P<0.01). CONCLUSIONS: The eyes with 1CU have good visual acuity and increased accommodative range more than the single-focus IOL. With the extension of time after surgery, the ability of 1CU regulation gradually declines, and nears point swift away gradually.

[Labeling neural stem cells with superparamagnetic iron oxide in vitro and tracking after implantation with MRI in vivo].

OBJECTIVE: To evaluate the feasibility of monitoring the neural stem cells implanted into the brain by the technique of labeling with superparamagnetic iron oxide (SPIO). METHODS: Neural stem cells were isolated from the cerebral cortex of newborn Wister rats and cultured. SPIO particles and poly-L-lysine were added into the medium to be co-cultured foe one hour. After the formation of neurospheres, Prussian blue staining was conducted and transmission electron microscopy was used to identify the iron particles in these neural stem cells. Sixteen adult female Wistar rats underwent transplantation of labeled neural stem cells into the right side of brain and non-labeled cells were transplanted into the contralateral part as controls. 1, 2, 4, 6, and 7 weeks after the transplantation, MRI examination with the scanning sequences of SE T2WI, FSE T2WI, and GRE T2 * respectively was conducted on the brains of the rats. Four rats at each time point were killed and their brains were taken out to undergo HE staining and Prussian blue staining to track the presence of labeled-cells. RESULTS: After the addition of SPIO the neurospheres continued to proliferate and differentiate normally. Electron microscopy showed vacuolar structures of different sizes under the cytoplasma membrane within and outside which there were high-density iron particles. Prussian blue staining showed numerous blue stained particles in the cytoplasm of the labeled cells. Remarkable low signal change was seen in the right brain transplanted with labeled cells, especially in the condition of scanning sequence of GRET2. Such change could be seen up to 7 weeks after the transplantation. No signal change was found in the left brain. CONCLUSION: SPIO labeling technique is useful in monitoring the outcome of transplanted neural stem cells.