Linguatula serrata in the anterior chamber of the eye

We report a case of intraocular Linguatula in healthy young female who presented with a history of trivial trauma, dislocated lens, inflammation and secondary glaucoma. A mobile worm was seen in the anterior chamber. Pars plana lensectomy and vitrectomy was planned to remove both the cataractous lens and the parasite during which the worm disappeared from view but was later recovered from the cassette fluid. It was identified as the nymphal form of Linguatula serrata (tongue worm).     

Effects of melatonin on Wi-Fi-induced oxidative stress in lens of rats

Introduction:

Melatonin has been considered a potent antioxidant that detoxifies a variety of reactive oxygen species in many pathophysiological states of eye. The present study was designed to determine the effects of Wi-Fi exposure on the lens oxidant, antioxidant redox systems, as well as the possible protective effects of melatonin on the lens injury induced by electromagnetic radiation (EMR).

Materials and Methods:

Thirty-two rats were used in the current study and they were randomly divided into four equal groups as follows: First and second groups were cage-control and sham-control rats. Rats in third group were exposed to Wi-Fi (2.45 GHz) for duration of 60 min/day for 30 days. As in the third group, the fourth group was treated with melatonin. The one-hour exposure to irradiation in second, third and fourth took place at noon each day.

Results:

Lipid peroxidation levels in the lens were slightly higher in third (Wi-Fi) group than in cage and sham control groups although their concentrations were significantly (P < 0.05) decreased by melatonin supplementation. Glutathione peroxidase (GSH-Px) activity was significantly (P < 0.05) lower in Wi-Fi group than in cage and sham control groups although GSH-Px (P < 0.01) and reduced glutathione (P < 0.05) values were significantly higher in Wi-Fi + melatonin group than in Wi-Fi group.

Conclusions:

There are poor oxidative toxic effects of one hour of Wi-Fi exposure on the lens in the animals. However, melatonin supplementation in the lens seems to have protective effects on the oxidant system by modulation of GSH-Px activity.     

Optical quality of hyperopic and myopic phakic intraocular lenses

Aims:

To assess and compare the optical quality of the myopic and hyperopic implantable collamer lens (ICL) from its wavefront aberrations for different powers and pupil diameters.

Settings and Design:

Prospective study.

Material and Methods:

The wavefront aberrations of two myopic (−3 and −6 diopters (D)) and two hyperopic V4b ICLs (+3 and +6D) were measured in vitro. To assess and compare the optical quality of different powers of ICLs, we analyzed the root mean square (RMS) of total higher order aberrations (HOAs), trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration at 3- and 4.5-mm pupil. In addition, the point spread functions (PSFs) of each ICL evaluated were calculated from the wavefront aberrations at 3- and 4.5-mm pupil.

Statistical Analysis:

A Student''s t-test for unpaired data was used for comparison between myopic and hyperopic ICLs.

Results:

Myopic ICLs showed negative spherical aberration, in contrast hyperopic ICLs showed positive spherical aberration, which increases when the ICL power increases, due to the innate optical properties of the lens. All ICLs evaluated had negligible amounts of other aberrations. We did not find statistical significant differences in any Zernike coefficient RMS values analyzed between myopic and hyperopic ICLs at 3- and 4.5-mm pupil (P > 0.05).

Conclusions:

Myopic and hyperopic ICLs provide good and comparable optical quality for low to moderate refractive error. The ICLs evaluated showed values of wavefront aberrations clinically negligible to affect the visual quality after implantation.     

Surgical management of spontaneous in-the-bag intraocular lens and capsular tension ring complex dislocation

We describe a technique to manage late spontaneous intraocular lens (IOL) and capsular tension ring (CTR) dislocation within the intact capsular bag. The subluxated IOL and CTR complex can be positioned in a closed chamber and fixed to the pars plana at both 3 and 9 o’clock quadrants with the presented ab externo direct scleral suturation technique which provides an easy, safe and effective surgical option for such cases.     

Spontaneous fracture of an implanted posterior chamber polyimide intraocular lens haptic: A case report

A 57-year-old male patient visited our clinic for decreased visual acuity in the right eye for 10 days. He denied any trauma history, but recalled that the symptom developed after straining. He had undergone uncomplicated phacoemulsification and posterior chamber intraocular lens (IOL) implantation in the bag of the right eye 11 years ago. The IOL was a three-piece silicone polyimide-haptics design. On slit-lamp examination, the IOL optic and proximal part of nasal fractured haptic were found in the anterior chamber. The distal part of fractured haptic was observed in the capsular bag. He underwent IOL exchange. The fracture site of the haptic was near the optic–haptic junction. This is the unique case report of a spontaneous fracture of an implanted posterior chamber polyimide IOL haptic, which implies the possibility of IOL haptic fracture in various haptic materials.     

Intraocular lens power calculation in eyes with short axial length

Aim:

To evaluate and compare the predictive capacity of four intraocular lens (IOL) power calculation formulas (SRK/T, Hoffer Q, Holladay 1, and Haigis) in eyes shorter than 22.0 mm.

Setting and Design:

Observational study.

Materials and Methods:

Participants in our study were 69 consecutive patients with a preoperative axial length (AL) of less than 22.0 mm in one or both eyes. All patients underwent phacoemulsification with IOL implantation and postoperative target of refraction was analyzed. Specifically, the differences in the mean absolute estimation error (AE) for the four formulas were analyzed. Furthermore, the percentage of eyes with AE within ±0.5 and ±1.0 D for each formula was estimated, as well as the correlation coefficient (r) between the AL and estimation error (E) for each formula. The Mann-Whitney U test was used to compare differences in the AEs of the formulas. A statistically significant difference was defined as P < 0.05.

Results:

The Haigis formula had statistically significant smaller mean AE in comparison to Holladay 1, Hoffer Q, and SRK/T. The Haigis formula predicted more eyes with E within ±0.5 and ±1.0 D of predicted spherical equivalent compared to other formulas. Correlation between AL and AE revealed a negative r value and P < 0.05 for all formulas.

Conclusions:

Haigis formula provides more accurate results concerning the postoperative target of refraction in eyes with AL less than 22.0 mm. Hoffer Q could be also used as an alternative.     

晶状体损伤对视神经损伤后RGCs的保护作用及其机制

背景大鼠Miiller细胞提取液能够促进离体培养的视网膜神经节细胞（RGCs）存活及轴突的再生,伴晶状体损伤的视神经外伤眼RGCs存活率提高,但Milller细胞和晶状体损伤在促进RGCs存活方面的关系鲜见报道。目的探讨伴晶状体损伤的视神经外伤眼Mtiller细胞对RGCs存活的促进作用及其机制。方法清洁级成年Wistar大鼠48只按随机数字表法随机分为伪手术组、视神经损伤组、晶状体联合视神经损伤组。伪手术组大鼠手术中暴露但不损伤视神经,视神经损伤组大鼠行视神经横断伤,晶状体联合视神经损伤组行视神经横断伤联合晶状体针刺伤,并导致晶状体混浊。术后7d及14d各组分别取8只大鼠处死后制备视网膜标本。采用苏木精一伊红染色观察各组大鼠视网膜和RGCs的形态学改变,采用免疫组织化学法检测各组大鼠视网膜内核层胶质纤维酸性蛋白（GFAP）标记的Muller细胞,光学显微镜下计数各组大鼠RGCs数量及GFAP阳性标记的Muller细胞数量。结果术后7d及14d,伪手术组大鼠RGCs的数量分别为（52．98±1．90）个／高倍视野和（51．81±3．09）个／高倍视野,差异无统计学意义（t=0．910,P=0．378）;术后14d视神经损伤组大鼠RGCs数量为（22．67±1．94）个／高倍视野,明显少于术后7d的（36．61±1．69）个／高倍视野,差异有统计学意义（t=15．312,P=0．000）;术后14d晶状体联合视神经损伤组RGCs数量为（35．69±1．80）个／高倍视野,明显少于术后7d的（50．76±2．77）个／高倍视野,差异有统计学意义（t=12．920,P=0．000）。术后7d及14d,晶状体联合视神经损伤组存活的RGCs数量均多于视神经损伤组,差异均有统计学意义（7d：t=102．840,P=0．000;14d：t=164．020,P=0．000）;术后14d晶状体联合视神经损伤组存活的RGCs：牧量少于伪手术组,差异有统计学意义（t=187．04,P=0．034）。术后7d及14d,伪手术组大鼠视网膜内核层均未见GFAP阳性标记的Muller细胞;视神经损伤组大鼠内核层GFAP阳性标记Muller细胞数量分别为（29．38＋2．04）个／高倍视野和（19．07±2．14）个／高倍视野,差异有统计学意义（t=-9．868,P=0．000）。晶状体联合视神经损伤组大鼠内核层GFAP阳性标记的Muller细胞数量分别为（48．96±2．80）个／高倍视野和（46．73±1．50）个／高倍视野,差异无统计学意义（t=1．987,P=0．067）。术后7d及14d,晶状体联合视神经损伤组大鼠内核层GFAP阳性Muller细胞数量均较视神经损伤组增多,差异均有统计学意义（7d：t=-15．997,P=0．000;14d：t=-29．938,P=0．000）。结论在视神经损伤合并晶状体刺伤时,晶状体损伤可诱导Muller细胞活化,进而促进视神经损伤后RGCs的存活。     

曲伏前列素对已行超声乳化人工晶状体植入术的POAG患者的眼压控制

目的：观察曲伏前列素滴眼液对已行白内障超声乳化人工晶状体植入术的原发性开角型青光眼患者的降眼压效果及安全性。

方法：采用随机、单盲、平行对照试验,选取白内障超声乳化人工晶状体植入术后的原发性开角型青光眼患者,治疗组入选43例43眼滴用曲伏前列素每日1次,对照组入选43例43眼滴用布林佐胺滴眼液早晚各1次,共观察12wk。观察的指标主要包括眼压、眼部症状以及不良反应等。

结果：治疗组眼压从(24.20±3.01)mmHg降至(16.77±2.89)mmHg; 对照组从(23.87±3.47)mmHg降至(18.81±3.07)mmHg,两组用药前后眼压相比均有显著差异(P<0.01),各时间点两组间眼压相比存在统计学差异(P<0.05)。用药后治疗组结膜充血及眼痒明显重于对照组,但不妨碍继续用药。未发现其他眼部改变和全身副作用。

结论：曲伏前列素对控制已行白内障超声乳化人工晶状体植入术的原发性开角型青光眼的眼压是高效和安全的。     

Late in‐the‐bag intraocular lens dislocation in eyes with pseudoexfoliation syndrome

Purpose:  To assess preoperative features, frequency, surgical approaches and outcomes of late in‐the‐bag dislocation of posterior chamber intraocular lenses (IOLs) in eyes with pseudoexfoliation syndrome. Methods:  Seventy‐seven patients (81 eyes) were enrolled. Inclusion criteria were patients with pre‐existing pseudoexfoliation syndrome who underwent surgery for late in‐the‐bag IOL dislocation between March 2004 and April 2010. Medical records were reviewed. Data from before and after secondary surgery were analysed. Results:  Mean time between cataract extraction and secondary surgery for late in‐the‐bag dislocation of posterior chamber IOLs was 8.5 years. The increase in frequency within the reviewed period was statistically significant, ranging from six patients in the first year to 25 patients in the final year (p = 0.004). When surgical correction was performed within 1 month of referral, deterioration of the dislocation occurred in only one of 23 patients (4.3%). Complications, especially vitreous loss, occurred significantly more frequently during exchange surgery (n = 23) when compared with scleral suturing (n = 50) (p < 0.0001). After surgery, however, no differences in complications (p = 0.98) or best‐corrected visual acuity (p = 0.74) was found. In general, following secondary surgery, there was a statistically significant improvement in best‐corrected visual acuity (p < 0.0001). Conclusion:  The frequency of late in‐the‐bag dislocation of posterior chamber IOLs in eyes with pseudoexfoliation syndrome increased during the observation period. Our study suggests that surgical repair should not be delayed beyond 1 month and that scleral suturing is preferable to exchange surgery, because of less intraoperative complications.