The ring of Soemmerring in the rabbit

The scanning ultrastructure of the remnants of the lens left in the eye after extracapsular lens extraction was investigated in the rabbit. Extracapsular lens extraction was performed in 25 eyes and the development of after-cataract followed by biomicroscopic examination. After survival times varying between 1 week and 12 months, the eyes were enucleated and the rings of Soemmerring treated for light microscopy and transmission and scanning electron microscopy. Soemmerring's ring consisted of the fused remnants of the dissected anterior and posterior lens capsule, enclosing the equatorial part of the former lens, left behind after the operation. The anterior capsule and, to a lesser extent, also the posterior capsule were multilayered and appeared to be thickened. While the remnant of the anterior capsule was lined by a monolayer of epithelial cells, the posterior part of the capsule was only partly lined by irregularly arranged epithelial cells. All epithelial cells were highly vacuolized. In transection the interior part of the ring consisted of normal fibers, irregularly oriented and irregularly shaped fibers, degenerated fibers, and globular amorphous masses. Many of the normal fibers contained cell nuclei. At the equator and at the posterior side of the fusing anterior and posterior capsule as well, the fiber organization resembled the lens bow region of normal lenses. Frequently, islands of epithelial cells were observed in the center of the ring. The vitreal face of the posterior capsule in the center of the ring (in the optic axis of the eye) seemed to be unchanged and on its pupillary surface, fibers of different size as well as fibroblastlike cells were found. However, clear-cut Elschnig's pearls were absent. Our results are compared with the observations summarized in the literature. It can be concluded that the epithelial cells in Soemmerring's ring retain their capacity for division and differentiation. The newly formed fibers seem to be pushed to the center of the ring and to degenerate.     

Pathology of intraocular lenses in 33 eyes examined postmortem

Thirty-three pseudophakic eyes from 29 patients were examined postmortem. Clinically, 25 of the eyes had had visual acuities of 20/50 or better. In general the intraocular lenses (IOLs) were quite well tolerated. Iris atrophy and erosion were prominent features of eyes containing an anterior chamber, iris fixation, or iridocapsular lens. Angle recession and ciliary-body erosion were found in some eyes with anterior chamber lenses. Ciliary-body erosion by haptics was seen with posterior chamber lenses. Pupillary membranes were present in eight eyes. Granulomatous reaction to IOL material was present in 13 eyes. Usually this was localized to the site of the lens haptic, and was consistent with good visual acuity. One eye with a posterior chamber lens had been successfully treated for Staphylococcus epidermidis endophthalmitis after capsulotomy, shortly before death. Central corneal endothelial cell loss seemed to be of similar amount for the anterior chamber, iris fixation, and iridocapsular lenses, but was less severe in eyes with posterior chamber lenses. Cystoid macular edema was present in five eyes, retinal phlebitis in two eyes, and retinal detachments in four eyes.     

Ultrasound biomicroscopic analysis of pseudophakic pupillary block glaucoma induced by Soemmering's ring

AIM: To perform ultrasound biomicroscopic analysis of pseudophakic pupillary block glaucoma induced by lens capsule and a Soemmering's ring and its resolution, and to elucidate the pathophysiology of this glaucoma. METHODS: A woman with pseudophakic pupillary block glaucoma underwent successful neodymium:YAG (Nd:YAG) laser photodisruption of the lens capsule through a laser iridotomised coloboma with resolution of the pupillary block. The Humphrey ultrasonic biomicroscope model 840 was employed to observe the anterior segment before and after laser photodisruption. RESULTS: Ultrasound biomicroscopic examination revealed the intraocular lens (IOL) was displaced forward, shallowing the central anterior chamber. The anterior hyaloid face was relatively posterior to the posterior capsule. The iris was in apposition to the anterior capsule, which was in touch with the IOL optics. A massive Soemmering's ring, which extended from the IOL optics to the ciliary processes, was displaced anteriorly. The Soemmering's ring consisted of several tightly packed layers. The ciliary processes rotated anteriorly. After Nd:YAG laser photodisruption of the capsule, ultrasound biomicroscopic images showed the resolution of the pupillary block and the anterior rotation of the ciliary process. The Soemmering's ring moved posteriorly, and the layers in the ring became loose. CONCLUSIONS: A massive Soemmering's ring may one of potential causes of pupillary block after cataract surgery. Ultrasound biomicroscopy is potentially useful as a non-invasive diagnostic technique for clinical diagnosis and differentiation between Soemmering's ring induced pupillary block glaucoma and other forms of pupillary block.     

Relationship between apparent accomodation and corneal multifocality in pseudophakic eyes.

OBJECTIVE: To investigate whether any association exists between apparent accommodation in pseudophakic eyes and multifocal corneal effects. DESIGN: A prospective observational case series. PARTICIPANTS: A total of 121 eyes of 98 patients who had undergone phacoemulsification and posterior chamber intraocular lens implantation were studied. METHODS: The amount of apparent accommodation was measured using an accommodometer. The degree of corneal multifocality was determined on the corneal topography by measuring the maximum and minimum corneal refractive powers within the pupillary area. Refractive astigmatism, keratometric astigmatism, pupillary diameter, and age were also analyzed. MAIN OUTCOME MEASURES: Apparent accommodation, corneal multifocality, refractive and keratometric astigmatism, pupillary diameter, and age. RESULTS: Multiple regression analysis revealed that corneal multifocality and pupillary diameter had significant positive correlations with apparent accommodation, whereas other explanatory variables showed no relationship with apparent accommodation. CONCLUSION: Multifocal corneal effects contribute to apparent accommodation in pseudophakic eyes.     

Results of penetrating keratoplasty for pseudophakic bullous keratopathy with the exchange of an intraocular lens.

We report on 29 consecutive patients with pseudophakic bullous keratopathy who underwent in one eye penetrating keratoplasty with an exchange of the original intraocular lens for a Pearce tripod posterior chamber lens, and who were available for a follow up of at least 12 months. The average interval between cataract extraction with lens implantation and the appearance of bullous keratopathy was five and a half years (range 10 months to 16 years). The mean follow-up period after penetrating keratoplasty was 36 months (range 12 to 56 months). The corneal graft remained clear in 22 (76%) eyes. One year after the operation 45% of the eyes had a vision of 20/40 or better, and 20% had visual acuities between 20/40 and 20/100. The remaining 31% had a vision of 20/100 or less (one unknown). Nine eyes (31%) had cystoid macular oedema or macular degeneration. 45% of the eyes had a refraction within approximately 2 dioptres of emmetropia. In patients with pseudophakic corneal oedema we continue to exchange the intraocular lens by a Pearce tripod posterior chamber lens sutured to the iris when it is necessary to remove the lens.     

Retinal detachment after intraocular lens implantation

Between August 1982 and July 1985, 19 eyes were operated for pseudophakic retinal detachment (PRD) (Anterior chamber lens in 13 eyes, posterior chamber lens in 3 eyes and iris supported lens in 3 eyes). The characteristics of these pseudophakic retinal detachments were very similar to those following intracapsular cataract extractions. Retina was re-attached in 18 eyes (95%), in 14 eyes, after one buckling procedure. In 4 eyes, altogether 12 surgical procedures were needed to re-attach the retina. Problems to visualize the peripheral retina, made it necessary to remove the IOL in 3 eyes (2 iris fixated and one in the anterior chamber).     

Results of Penetrating Keratoplasty for Pseudophakic Corneal Edema With Retention of intraocular Lens

We reviewed the records of 26 consecutive patients undergoing penetrating keratoplasty for pseudophakic corneal edema in which the original intraocular lens was retained. The average interval between lens implantation and penetrating keratoplasty was 31.5 months. Follow-up after keratoplasty ranged from 11 to 59 months, with an average of 24.5 months. Six patients had anterior chamber lenses; sixteen, iris or iridocapsular lenses; and four, posterior chamber lenses. A vitrectomy was performed in 14 (54%) patients. Of the 21 patients with clear grafts (80%), 8 (38%) had vision of 20/40 or better while 7 (33%) had acuities of 20/200 or worse. Visual acuity of 20/40 or better was attained by 3 of 4 (75%) patients with posterior chamber lenses but only 3 of 16 (19%) patients with iris-supported lenses. Cystoid macular edema was the principal cause of decreased acuity in 12 of the 13 patients with clear grafts and acuity less than 20/40. Angiographic confirmation was obtained in 7 of 12 patients. Overall, the results are similar to those reported for pseudophakic keratoplasty with intraocular lens removal. No adverse effect of retaining a securely fixated intraocular lens was demonstrated.     

儿童后发性白内障合并人工晶状体固定性瞳孔夹持的手术治疗

目的探讨儿童严重后发性白内障合并人工晶状体固定性瞳孔夹持的合理的治疗方法及疗效。方法对14岁以下发生严重后发性白内障的患者中合并人工晶体固定性瞳孔夹持伴有严重的虹膜后粘连或瞳孔膜闭的12只眼进行后发性白内障切除、人工晶状体复位术,部分病人联合前段玻璃体切割术。对虹膜后粘连或瞳孔膜闭者同时进行粘连分离或瞳孔成形术。结果12只眼成功分离虹膜与囊膜粘连并进行后发性白内障切除和人工晶状体复位。其中2只眼行瞳孔成形术,8只眼行前段玻璃体切割术,术后视功能有不同程度的改善。结论伴有严重人工晶状体瞳孔夹持和虹膜粘连或瞳孔膜闭的儿童严重后发性白内障的理想治疗手段是手术切除后发性白内障并进行人工晶状体复位。     

儿童外伤性白内障人工晶状体固定性瞳孔夹持的原因与手术治疗

目的 回顾性分析儿童外伤性白内障摘除术后人工晶状体(IOL)固定性瞳孔夹持的原因,并探讨有效的治疗方法.方法 对14岁以下外伤性白内障的患者行白内障摘除后房犁人工晶状体植人术后固定性瞳孔夹持患者10例(10只眼),分析其发生原因及并发症,并行虹膜粘连分离,后发性白内障切除,人工晶状体复位术及前段玻璃体切割术.5只眼行IOL置换术.结果 10只眼成功完成分离虹膜与囊膜粘连并行后发性白内障切除和人工晶状体复位,术后视功能不同程度的改善.结论 外伤性白内障术后葡萄膜炎反应,瞳孔粘连,后发性白内障及周边皮质再生是引起儿童IOL固定性瞳孔夹持的重要原因.手术分离虹膜粘连、清除晶状体再生皮质并切除后发性白内障可有效复位IOL.     

Retinal detachment in pseudophakia

In a group of 2,281 eyes after extraction of a cataract and implantation of an iris clip lens (1,362 eyes after intracapsular extraction and 927 eyes after extracapsular extraction) motion of the retina occurred in 36 eyes (1.67%), incl. 27 after intracapsular extractions (1.98%) and 9 after extracapsular extractions (0.97%). In patients with pseudophakic retinal detachment after implantation of an iris clip lens the frequency of factors which might interfere with the development of this complication was investigated. The latter proved to be the following: prolapse of the vitreous body, luxation of the implanted lens, posterior uveitis and myopia. Detachment of the retina was preceded by: peroperative prolapse of the vitreous body in 34.21%, luxation of the implanted lens in 28.95%, posterior uveitis in 36.85% and myopia (up to -4.0 Ds) in 21.05%. Anatomical and functional results after operation of pseudophakic motion were evaluated in 38 eyes (36 eyes operated on account of cataract in the authors' department, two in other departments). The minimal follow up period after operation of retinal detachment was six months. Anatomical restoration of the retina was achieved in 23 eyes (60.53%), in 9 eyes a residual motion remained (23.68%) and in four eyes total motion (10.53%). In two eyes keratopathy developed (5.26%). Central vision 6/6-6/12 was achieved in 18.42%, 6/15-6/36 in 21.05%, 6/60-3/60 in 28.95% and less than 3/60 in 31.58%. In the poorer anatomical and functional results after operation of pseudophakic motions participate in addition to the above mentioned ones difficult visualization of the retinal periphery and the extent of surgical trauma during surgery of detached retinas.     

Pathogenesis of pupillary capture after posterior chamber intraocular lens implantation.

Pupillary capture is an unusual complication of posterior chamber intraocular lens implantation and may occur in the early or late postoperative period. We describe a series of patients with early or late onset pupillary capture and describe the pathogenesis. Early capture results from mechanical factors and is usually preventable. Late capture may be mechanical but is usually a sequel to the formation and subsequent contraction of iridocapsular synechiae. Synechiae result from lens epithelial or iris stromal hyperplasia and myofibroblastic metaplasia; they may be minimised by an atraumatic technique and adequate control of postoperative inflammation. The effect of pupillary capture is largely cosmetic, and we encountered no specific complications attributable to it.     

Vitrectomy for chronic pseudophakic cystoid macular edema.

PURPOSE: We report the results of pars plana vitrectomy for chronic pseudophakic cystoid macular edema unresponsive to medical treatment. METHODS: Retrospective analysis of 23 consecutive eyes of 23 patients with chronic pseudophakic cystoid macular edema was performed. Eyes with vitreous incarceration into the cataract wound or vitreous-cornea contact were excluded from the study. Preoperatively, all eyes had cystoid macular edema confirmed on fluorescein angiography and were unresponsive to medical treatment. Pars plana vitrectomy was performed using standard techniques and vitreous adhesions to the iris, intraocular lens, or both were lysed if present. RESULTS: The mean interval between cataract surgery and vitrectomy was 32.3+/-30.9 months (median, 20 months; range, 3 to 110 months). The vitreous was adherent to the iris or intraocular lens in 12 eyes (52.2%) and was present in the anterior chamber with no evidence of adhesions in seven eyes (30.4%). In four eyes (17.4%) the vitreous was posterior to the iris plane with no adhesions to anterior segment structures. The median preoperative best-corrected visual acuity was 20/200, and the median final postoperative best-corrected visual acuity was 20/60 (P<.0001) after a mean follow-up of 30.2+/-31.2 months (median, 14 months; range, 2 to 109 months). Final best-corrected visual acuity improved by a mean of 3.3+/-2.6 Snellen lines, with a median percent change of 70% (mean, 57.3%; range, 0% to 99%). In all 23 eyes the cystoid macular edema resolved postoperatively by biomicroscopic examination in a mean period of 3.3 months (median, 2 months; range, 1 to 12 months). CONCLUSIONS: In pseudophakic eyes with chronic cystoid macular edema unresponsive to medical treatment, vitrectomy resulted in resolution of the cystoid macular edema with improved visual acuity in some cases. Clinical improvement may occur in eyes with no apparent vitreous disturbance.     

Fuchs异色性虹膜睫状体炎白内障手术的疗效分析

目的：评估Ｆｕｃｈｓ异色性虹膜睫状体炎（ＦＨＩＣ）患者白内障囊外摘除术以及人工晶体（ＩＯＬ）植入术后的产７及并发症。方法：３２例ＦＨＩＣ患者行白内障手术，其中１７例植入后房型人工晶体（ＰＣＩＯＬ），另１５例患者行单纯的白内障囊外摘除术。结果：矫正视力在０．５及以上的患者中，ＩＯＬ组１４只眼（８８％），而无晶体眼１２只眼（８０％）。术 症为虹膜出血１２只眼，瞳孔不能散大６只眼，悬韧带离断、玻璃体脱出     

不同术式晶状体摘除术后兔眼后发性白内障形成的组织病理学分析

目的：探讨可有效预防后发生白内障发生的内白障手术式方式。方法：将18例实验家兔随机分为A、B、C3个组,分别进行超声乳化晶状体吸附术、超声乳化晶状体吸附联合后囊膜连续环形撕囊术及超声乳化晶状体吸除联合的囊膜连续环形撕囊及前部玻璃体切除术。术后3个月对3个组术眼进行裂隙灯、眼底、组织病理学及电镜检查。结果：术后3个月3组术眼周边囊膜的混浊情况相似;A、B组术眼中央视区混浊情况相似,C组多数术眼中央视区清亮。3个组均无玻璃体疝、视网膜脱离及黄斑囊样水肿等并发症发生。3个组周边后囊膜均可见形态改变的晶状体上皮细胞及程度相似的Elschnig小体和晶体状纤维。A组后囊膜中央可见Elschnig小体及晶体纤维。B组可见与后囊膜撕囊孔相连续的纤维增生,C组后囊膜撕囊孔缘未见明显病理改变,无纤维增生。结论：超声乳化白内障吸除联合后囊膜连续环形前部玻璃体切除术可有效预防中央视区后发性白内障的发生;远期疗效尚需进一步观察。     

Role of ultrasound biomicroscopy in managing pseudophakic pupillary block glaucoma

We describe a case of anterior capsule adherence to the iris that occurred after phacoemulsification with in-the-bag intraocular lens (IOL) implantation. This adherence led to the development of pseudophakic pupillary block glaucoma. There were no synechias at the pupillary margin associated with the capsule-iris adherence. Ultrasound biomicroscopy, used to evaluate the anterior segment in vivo, clarified the mechanism of pseudophakic pupillary block. The pupillary block was relieved by a single laser iridotomy.     

Effect of lens implants on iris fluorescein angiography and the iris pigment layer

Fourteen eyes underwent cataract operation and implantation of an iris fixated (Medallion) pseudophakos. Eleven had an uncomplicated per- and post-operative course (group 1), 3 had a subluxation of the lens implant (group 2). The control group (group 3) consisted of the 14 contralateral eyes from group 1 and 2. Two cadaver eyes had a similar lens implanted (group 4). Groups 1-3 were investigated by bilateral simultaneous iris fluorescein angiography and retroiridal stereo transillumination photography. In group 1, one case with pupillary and diffuse semiperipheral leakage areas was observed, in a clinically healthy eye 15 months after the operation. An other one had some leakage at the pupillary border, but not in the area of contact with the loops. Rubbing between iris surface and some parts of the lens did not provoke local leakage. No new vessel formation was found. Pigment layer defects were observed in every operated eye, but no leakage was related to them except in the two pupillary areas mentioned. Mayor pigment defects did not progress in a quiet eye. The iris seems to be to some degree resistant to contact with the parts of the intraocular lens implant.     

儿童人工晶状体固定性瞳孔夹持的原因和手术复位

目的　分析儿童白内障摘除术后人工晶状体 (IOL)固定性瞳孔夹持的原因 ,并探讨有效的处理方法。方法　收集年龄 <14岁、白内障摘除后房型IOL植入术后发生固定性瞳孔夹持患者 30例 (31只眼 )的临床资料 ,分析其发生原因和并发症 ,并对其中 8例 (8只眼 )合并严重并发症患者行IOL复位手术。结果　全部患者均发生较严重的葡萄膜炎性反应及其所致的虹膜后粘连和瞳孔膜闭或闭锁 ,以及不同程度的后发性白内障。IOL复位手术中可见 8例患者均发生不同程度的晶状体周边皮质再生。结论　白内障摘除术后葡萄膜炎性反应、晶状体皮质再生及后发性白内障是引起儿童IOL固定性瞳孔夹持的主要原因。手术分离虹膜粘连、清除晶状体再生皮质并切除后发性白内障 ,可有效复位IOL。     

Pupillary peaking with exposure of an intraocular lens positioning hole corrected by Nd:YAG laser treatment

After posterior chamber intraocular lens insertion, a patient complained of "glare" and of seeing an "extra line." The pupil was seen to be "peaked" at the 10-o'clock meridian, exposing a lens positioning hole. Following dilation, adhesions between the anterior capsule remnants and the posterior iris surface were seen. These adhesions were severed with a Nd:YAG laser, restoring the normal pupillary shape and eliminating the patient's optical aberrations.     

Ultrasound biomicroscopy in evaluation of conditions for secondary intraocular lens implantation in aphakia

In order to evaluate conditions for secondary intraocular lens (IOL) implantation detailed analysis of ultrasound biomicroscopy (UBM) images of 26 patients (33 eyes) with aphakia was performed. The etiology of cataract was congenital (12 eyes), traumatic (9 eyes), senile (8 eyes) and uveal (4 eyes). The results showed that UBM provides an opportunity to evaluate the implantation site considering capsule integrity, configuration and parameters of ciliary line. The authors have demonstrated that UBM is scarcely the only visualization method in aphakic eyes that lets find and evaluate structural changes of the globe, induced by trauma, uveitis or improper lens removing during cataract surgery (iridocapsular or iridocorneal synechiae, iris defects, pupillar membranes, lens remnants, vitreoretinal proliferation and others). The authors propose UBM to be included into diagnostic examination of patients with aphakia before secondary IOL implantation and consider the results of UBM in choice of lens model and type of fixation.     

Histopathological examination of two cases of anterior staphyloma associated with Peters' anomaly and persistent hyperplastic primary vitreous

AIMS: To clarify the developmental mechanism and critical period for the uncommon complex of Peters' anomaly and persistent hyperplastic primary vitreous (PHPV). METHODS: Two eyes with Peters' anomaly and PHPV were histologically examined by serial section. One eye was enucleated at age 7 months (case 1) and the other at age 4 months (case 2) owing to severe anterior staphyloma. RESULTS: In both eyes, defects in the endothelium, Descemet's membrane, and posterior stroma were observed in the central cornea, and the degenerative lens adhered to the posterior surface of the defective corneal stroma. Also, in both eyes, the anterior chamber space was not formed and the undifferentiated iris stroma adhered to the posterior surface of the peripheral cornea. Mesenchymal tissue containing melanocytes was observed behind the degenerative lens, and the pigment epithelium was absent at the lower nasal side of the ciliary body in case 1. In case 2, mesenchymal tissue containing scattered melanocytes in the vitreous cavity was seen on the posterior retina. Based on the histological findings, both cases were diagnosed as Peters' anomaly caused by the faulty separation of the lens vesicle, PHPV, maldevelopment of the iris and ciliary body, and goniodysgenesis. CONCLUSION: Migratory disorders of neural crest cells from 4 to 7 weeks of gestation may be responsible for various ocular anomalies including Peters' anomaly and PHPV, as observed in these cases.