Is There a Latent Period for the Surgical Treatment of Children With Dense Bilateral Congenital Cataracts?

BACKGROUND: It generally is accepted that cataract surgery during the first 6 weeks of life is associated with the best visual outcomes for children with dense unilateral congenital cataracts. The latent period for children with dense bilateral congenital cataracts has not been clearly defined. METHODS: The best-corrected visual acuity (BCVA) at 4 to 6 years of age was collected retrospectively on a series of 43 children with dense bilateral congenital cataracts from 4 institutions. All of the children underwent a lensectomy, posterior capsulotomy, and anterior vitrectomy at 36 weeks of age or younger. RESULTS: Cataract surgery was performed at a mean age of 11.5 weeks for the better-seeing eye. BCVA was assessed when the children were a mean of 5.3 years of age. The visual acuities of 26 (60%) were 20/40 or better, 12 (28%) were 20/50 to 20/80, and 5 (12%) were 20/100 or worse. There was a trend for worse BCVA with increasing age at the time of surgery (r = 0.28, P = 0.07). We noted that a BCVA of 20/100 or worse occurred only among eyes undergoing surgery when infants were older than 10 weeks (10 weeks: 5/22 = 23%, P = 0.049). Children with preoperative nystagmus had worse visual outcomes; only 38% of children with preoperative nystagmus achieved a BCVA of 20/40 or better compared with 74% of children without preoperative nystagmus (P = 0.03). CONCLUSION: Previous reports have proposed that cataract surgery during the first 5 to 8 weeks of life is associated with better visual outcomes in children with dense bilateral congenital cataracts. Our results would suggest that good visual outcomes can be achieved beyond this age, but the incidence of poor visual outcomes increases if cataract surgery is delayed beyond 10 weeks of age. The absence of preoperative nystagmus is a better predictor of a good visual outcome than the age at surgery.     

Advances in the management of congenital and infantile cataract

Congenital and infantile cataracts produce deprivation amblyopia and can thus cause lifelong visual impairment. Successful management is dependent on early diagnosis and referral for surgery when indicated. Accurate optical rehabilitation and postoperative supervision are essential.The timing of surgery and its relationship to the duration of deprivation is important. Unilateral congenital cataract surgery within 6 weeks of birth produces the best outcomes. The equivalent 'latent' period for bilateral visual deprivation may be longer at around 10 weeks.Visual deprivation has a significant impact on the development of fixation stability. Major form deprivation, even after early surgery, leads to nystagmus. This is mostly manifest latent nystagmus (MLN). The latent period for fixation stability may be as short as 3 weeks. Preoperative congenital nystagmus (CN) can convert to more benign MLN after surgery.Infantile IOL implantation is becoming increasingly accepted. A satisfactory long-term refractive result requires that allowance be made for childhood axial growth and myopic shift. In a series of 25 infants (33 eyes) implanted before 12 months of age, the mean myopic shift at 12 months was 4.83 D. This increased to 5.3 D in infants implanted before 10 weeks. The initial desired refractive outcome following IOL implantation is thus hypermetropia, with the degree dependent on the age of the child.Glaucoma or ocular hypertension is a common complication following paediatric cataract surgery. Microphthalmia and surgery in early infancy are risk factors. Tonometry results may be influenced by the increased corneal thickness seen in aphakic and pseudophakic children. The long-term prognosis of eyes with aphakic glaucoma is not necessarily poor but intraocular pressure control may require three or more medications. Surgical intervention appears to be necessary in over a quarter of eyes.Posterior capsule opacification (PCO) is common in infants undergoing primary lens implantation. Primary capsulotomy and anterior vitrectomy reduce the risk of PCO. In the absence of anterior vitrectomy, primary posterior capsulotomy does not prevent visual axis opacification.Further developments will continue to be driven by clinical research. The prevention of capsule opacification and cellular proliferation may in future be achieved by the use of devices to specifically target epithelial cells at surgery.     

Treatment of manifest latent nystagmus

Eight patients with manifest latent nystagmus, as noted by ocular movement recordings, were examined for nystagmus reduction after surgical or optical treatment. Seven of the patients had strabismus. Five patients underwent strabismus surgery, had no tropia postoperatively, and the manifest latent nystagmus converted to latent nystagmus. Four of these five patients subsequently showed improvement in binocular visual acuity. Three patients received optical treatment; one had accommodative esotropia and, with appropriate spectacle correction, the manifest latent nystagmus was converted to latent nystagmus with improved vision. In the other two patients the manifest latent nystagmus lessened after correction with appropriate spectacles; binocular visual acuity of one of these patients improved. The possibility of converting manifest latent nystagmus to latent nystagmus by strabismus surgery is a reasonable surgical goal. In patients with manifest latent nystagmus and strabismus, surgical or optical alignment of the eyes decreases the nystagmus intensity and may also improve binocular visual acuity.     

儿童弱视图形反转视觉诱发电位P100波的变化特点

目的探讨正常与弱视儿童的图形反转视觉诱发电位(PR-VEP)的P100波差别及弱视眼经短期治疗后的P100波变化.方法选择弱视患儿36例(67眼)及正常儿童30例(60眼),采用丹麦DANTEC多导视觉电生理检测仪进行检查.结果正常组与中、重度弱视之间P100波潜伏期和振幅均存在高度显著性差异(P＜0.01);而正常组与轻度弱视间P100波潜伏期无明显差异(P＞0.05),但振幅则有明显差异(P＜0.05).并发现轻、中、重度弱视眼经过3个月综合治疗,视力虽有提高,但各程度弱视治疗前后的100波潜伏期和振幅均无明显改善(P＞0.05).结论中、重度弱视眼PR-VEP100波潜伏期延迟,振幅降低.轻、中、重度弱视经短期治疗后P100波无显著变化,预示其视觉传导功能并没有明显的改善.     

LVC程序视野检查在白内障手术中的应用

目的　探讨中央低视力(lowvisioncenter ,LVC)程序视野检查在术前评估白内障低视力患者视功能的价值。方法　白内障低视力患者共30例30眼,其中合并青光眼、入院后行青白联合术者2 1例2 1眼;无青光眼史、单纯行白内障手术者9例9眼。术前1日及术后3月内行LVC程序视野检查。术前同时行视网膜潜视力测定。结果　所有患者在术后总的平均阈值敏感度(meansensi tivity,MS)均有显著提高(P <0. 0 1) ,而颞侧的MS值较鼻侧的MS值改善更为明显。术前视野已有绝对暗点形成的区域,术后仍存在。与视网膜潜视力测定相比,LVC程序视野检查的MS值与术后最佳矫正视力间存在更好的对应关系。结论　术前LVC程序视野检查对于白内障尤其是合并青光眼低视力患者有特殊价值,有助于术者判断该类患者术后的视力、视野的情况,可作为术前估计其潜在视功能的新方法之一     

Detection of latent disorders of visual function during ambulatory care of children

For the purpose to select tests for diagnosis of latent disturbances of visual functions, dynamic observation was conducted over 88 healthy school children within 5 years (from the 3d to the 8th form). Once a year, the children underwent examination of visual acuity for far and near, the state of binocular vision on a synoptophore and a color test, the volume of relative and absolute accommodation, muscular balance of eyes for far and near, contrast sensibility, the time of perception of the negative successive contrast, refraction. For the period of 5 years, 7 children developed myopia of low degree, 32 showed transitory or lasting reduction of visual acuity due to spasm of accommodation. The authors believe that the most rapid and informative tests for diagnosis of latent disturbances in accommodation-convergence system are visual acuity for near, the volume of absolute accommodation, the threshold of remote vision, muscular balance of eyes for near. It is recommended to use these tests widely when conducting ophthalmologic thorough prophylactic examinations of children.     

Nystagmus

Ophthalmologic nystagmus can be congenital and manifest/latent both of whose waveforms, compensatory mechanisms, and treatment are different. Physiologically, latent nystagmus may be reversed at will, whereas nystagmus and head nodding may be simultaneously triggered at will. Occasional oscillopsia is more frequent than is usually believed; extraretinal signals may be a reason for their absence in congenital nystagmus. Astigmatism could be the consequence of nystagmus, myopia is present in most of the cases of congenital nystagmus with blocking convergence, whereas depth-of-focus anomalies are probably due to the presence of nystagmus during its critical period of development. As for treatment, botulinum toxin injection, because of its temporary effect, is not used to treat nystagmus but to help in decision-making for surgery. Four large horizontal recti recession is the last-resort surgery which may be combined with other surgical procedures and can give unexpected results. Artificial divergence surgery by contrast is one of the most valuable procedures used in congenital nystagmus.     

间歇性外斜视患儿术后视功能及多焦视觉诱发电位的变化

目的:探讨间歇性外斜视术对斜视患儿视功能及多焦视觉诱发电位的影响。方法:选取2014-01/2017-12期间就诊的91例间歇性外斜视患儿为研究对象,所有患儿均手术治疗。观察患儿手术前后视功能变化情况,检测其手术前后多焦视觉诱发电位水平。结果:术后1wk总有效率为88%,术后6mo总有效率为86%;术前患儿平均斜视度为-38.12△,术后为-5.8△。术后6mo同时视、融合、远立体视的患儿例数较术前显著增加(P<0.01);术后6mo患儿正位率为68%;术前三级视功能都存在或只存在其一二者术后绝大多数为正位,相比其丧失者术后正位率明显较高(P<0.05)。自术前至术后6mo患儿第四环、第六环的特征峰振幅反应密度与鼻侧、颞侧视网膜潜伏期水平均显著升高,下方视网膜潜伏期水平显著下降(P<0.05)。结论:间歇性外斜视术可有效提高患儿视功能,促进患儿眼位的恢复,且术后患儿多焦视觉诱发电位水平也得到一定改善,临床效果突出。     

Asthenopia in Schoolchildren,Orthoptic and Ophthalmological Findings and Treatment

The aim of this study was to describe the orthoptic and ophthalmological findings in schoolchildren with asthenopia, to correlate them with asthenopic symptoms and to evaluate the effect of treatment. One hundred and twenty schoolchildren, aged 6–16 years, were included in the study. They were all referred by school nurses, for asthenopic symptoms. An orthoptic and ophthalmological assessment was performed. The main diagnoses were accommodative insufficiency, convergence insufficiency, refractive errors, and latent strabismus. Reading glasses could help 98% of the schoolchildren with reduced accommodation, and 94% of the children with refractive errors and heterophorias were helped with appropriate spherical, cylindrical and prism correction. Convergence exercise reduced the symptoms in all patients with convergence insufficiency. Ninety-three percent of all 120 schoolchildren were symptom free 3–6 month after treatment had started. By an orthoptic and ophthalmological examination abnormalities in schoolchildren with asthenopia related to visual problems can be identified. Most of the children were relieved from their symptoms by giving adequate glasses, convergence exercises and surgery.     

Pathological convolutions of internal carotid arteries as one of the causes of visual dysfunction in children

Visual evoked potentials (VEP) in response to reverse chess patterns were studied in 68 patients aged 7-14 years with pathological convolutions of internal carotid arteries and 25 healthy children. The latent period was increased and the amplitude of P100 peak decreased in the patients, which was indicative of dysfunction of the visual route. VEP changed at early stages of cerebral circulation insufficiency. The relationship between hemodynamic parameters and VEP values was proven. Increased latent period and decreased amplitude of the positive peak are the criteria of neurophysiological significance of pathological convolutions in the internal carotid arteries.     

Alternate Day Exotropia

Introduction: Cyclic strabismus is a rare disorder in which manifest strabismus and controlled latent deviation (heterophoria) alternates on a regular pattern which is usually over a 48-hr period. During the “straight” period the patient has a fully controlled heterophoria for all distances, with very good fusion and stereopsis. During the “squinting” period the patient has a constant manifest strabismus for all distances, with no demonstrable fusion and stereopsis.

Method: We describe 2 cases of alternate day exotropia. One patient requires strabismus surgery to obtain constant binocularity. The second patient underwent surgery for an intermittent exotropia and subsequently developed an alternate day exotropia. The condition very gradually reduced over the years and the patient is now fully binocular.

Conclusion: We report the first 2 cases of cyclic exotropia in non-Japanese female children presenting from about 1 to 3 years of age, without ocular or systemic pathology.     

Ahmed valve drainage implant surgery in the management of paediatric aphakic glaucoma

BACKGROUND: Paediatric aphakic glaucoma presents months or years after cataract surgery in children and is a major long term complication. The results of surgical treatment are poor and many children require multiple and repeat procedures with poor visual outcomes. METHODS: 13 children (19 eyes) had Ahmed valve implantation surgery, nine of the children had previous procedures such as cycloablation or trabeculectomy. Mitomycin was used at surgery in some patients and valve needling with Healon GV and 5-fluorouracil in some blebs after surgery. SF(6) gas was also used at the time of surgery in most children to reform the anterior chamber. RESULTS: 12 of the children (18 eyes) achieved intraocular pressure control of 15 mm Hg or less with a valve alone or with additional medical therapy. CONCLUSION: Ahmed valve implantation surgery alone or in combination with medical therapy is successful and safe in the management of paediatric aphakic glaucoma.     

Corneal nerves are necessary for adrenergic reactivation of ocular herpes

Herpes simplex virus type 1 (HSV-1) can infect the cornea and achieve ganglionic latency. HSV-1 can later be activated by a variety of effectors although the exact mechanism of reactivation is unknown. Rabbits harboring latent HSV-1 strain McKrae can be induced to shed virus by ocular iontophoresis of epinephrine to the cornea. No studies have been done to investigate if corneal nerves are necessary for epinephrine induction of HSV-1 ocular shedding. We did penetrating keratoplasty (PKP) in one eye each of 23 rabbits; the other eye served as an unoperated control. The surgery effectively denervates the area of the transplant for up to 90 days. Eighteen rabbits carrying latent HSV-1 strain McKrae received corneas from uninfected rabbits. Five uninfected rabbits with no latent virus received corneas from rabbits harboring latent HSV-1. On days 10-14 after penetrating keratoplasty, 24 eyes in the HSV-1 latent group and all ten uninfected eyes received iontophoresis of 0.01% epinephrine (0.8 mAmps for 8 min or 0.6 mAmps for 6 min) once daily for 3 days by means of an eye cup whose diameter was less than the diameter of the transplant. Six rabbits in the HSV-1 latent group received intravenous injections of cyclophosphamide (75 mg/kg) and dexamethasone (4 mg/kg). Following iontophoretic or immunosuppressive induction, the eyes were swabbed daily for 9 days. Of the 12 rabbits with latent virus which were treated by iontophoresis, one of the transplanted eyes and eight of the nontransplanted eyes were induced to shed virus. The mean duration of shedding in the nontransplanted eyes was 3.25 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Four-incision capsulorhexis in pediatric cataract surgery

Pediatric cataract surgery is challenging, with multiple differences from cataract surgery in adults; however, an ideal capsulorhexis is the major prerequisite for both. Capsulorhexis in children is more difficult due to the more elastic nature of the anterior capsule. I describe a technique for anterior and posterior continuous curvilinear capsulorhexes in pediatric cataract surgery using 4 arcuate incisions. The results in 10 eyes of 10 children are presented.     

Results of early treatment of congenital strabismus]

The authors analyse the results obtained after very early treatment of Esotropia in 38 children. These children were divided into 4 groups according to their age at the time of treatment. At the age of 30 months, they studied binocular vision, manifest latent nystagmus (NML) and dissociated vertical deviation (DVD). In groups 1 and 2, treatment was instituted before the age of 6 weeks (13 children) no DVD was noted, only one NML and 11 children have binocular vision. In groups 3 and 4, treatment was instituted after the age of 3 months (25 children) 4 cases of DVD and 10 of NML are noted, and only 9 children have binocular vision. In case of congenital esotropia, the authors recommend treatment before 2 months old to obtain a possibility of binocular vision and to decrease the risk of NML and DVD.     

直肌后徙可调缝线术在儿童共同性斜视中的应用

目的：观察直肌后徙可调整缝线术治疗儿童共同性斜视的临床效果。方法对34例儿童共同性斜视在全麻下采用直肌后徙调整缝线术治疗,术后1～2 d内进行缝线调整,随访6～24个月,观察手术效果。结果34例儿童共同性斜视患者中,11例达正常眼位,23例因欠矫或过矫需要调整,其中过矫9例及欠矫11例均调至正位,有3例欠矫者经集合训练后得到改善。在6～24个月随访中,未调整的患者中欠矫1例,经过调整的患者中欠矫2例,术后视功能较术前有明显的改善。结论采用可调整缝线治疗儿童共同性斜视是简便而有效的手术方式,可以减少再次手术风险,使儿童全麻斜视矫正手术的成功率获得较大的提高。     

隐匿性巩膜裂伤47例临床分析

目的:探讨隐匿性巩膜裂伤临床表现和手术方法方法:总结2000-05/2004-05因隐匿性巩膜裂伤而行手术治疗的47例(47眼),分析其致伤原因、临床表现、手术方法及结果。结果:术后视力≥0.05者20眼,视力<0.05者12眼,眼球萎缩10眼,眼球摘除5眼。结论:隐匿性巩膜裂伤主要由眼挫伤引起,应及时根据临床表现进行手术探查,缝合伤口,预防并发症发生。     

Adjustable sutures in children using a modified technique.

PURPOSE: Adjustable-suture techniques are commonly used to decrease the reoperation rate in adults undergoing strabismus surgery, but they are infrequently used in children because of the difficulty of performing adjustments on a conscious child. The purpose of this study is to evaluate a new technique for using adjustable sutures in children, which makes the second stage of the procedure unnecessary if no adjustment is needed. METHODS: This was a retrospective study of children who underwent surgery for exotropia or esotropia. The technique used was a variation of the standard fornix-based adjustable suture with a separate slipknot. The pole sutures were buried within the sclera and tied; then the incision of the conjunctiva was closed to cover the adjustable sutures. The patients were then measured 4 to 6 hours after the initial surgery. The decision of whether to adjust was based on predetermined criteria. Those children not adjusted were discharged with no further manipulation needed because the conjunctiva was already closed. For those children who were adjusted, the adjustment was made with the patient under intravenous propofol sedation or laryngeal mask anesthesia. RESULTS: A total of 61 consecutive children ages 12 months to 14 years underwent surgery using this technique. Patients were followed-up after surgery for a minimum of 6 weeks (median 19.4). Fifty-four of the 61 patients (88%) were within 10 prism diopters (PD) of orthophoria on their final postoperative visit. Of the 22 patients who underwent an adjustment, 20 (91%) were within 10 PD of orthophoria at their final postoperative visit. The median follow-up was 19.4 weeks (range 6 to 45.9). CONCLUSIONS: This new adjustable-suture technique was associated with excellent short-term eye alignment. It is particularly suited for pediatric surgery because it eliminates the necessity of further manipulation of children who do not require adjustment.     

Surgically induced necrotising sclerokeratitis (SINS)--precipitating factors and response to treatment.

The clinical features, treatment, and visual outcome of 52 eyes from 43 patients who developed scleritis following surgery were reviewed. In all patients the scleral inflammation developed adjacent to a surgical wound. Ninety six per cent had necrotising disease and 23% also had evidence of secondary posterior scleritis. Many different types of ocular surgery were implicated and the majority (75%) of the patients had two or more surgical procedures before the onset of the scleritis. Although cataract extraction through a limbal incision resulted in the largest subgroup, scleritis also followed glaucoma, strabismus, and retinal detachment surgery. The latent period between surgery and the appearance of inflammation was short (mean 9 months) except for a small group in whom scleritis occurred many years after squint surgery. Sixty three per cent of patients had evidence of a systemic disease. Early diagnosis and aggressive medical treatment significantly improved the visual outcome. The precipitating factors, pathogenesis, and course of this condition are discussed.     

New techniques and technologies for pediatric cataract surgery

PURPOSE OF REVIEW: This paper surveys the literature from April 2004 to April 2005 and addresses trends in pediatric cataract surgery techniques. RECENT FINDINGS: The evolution of pediatric cataract surgery continues, with many adult cataract surgical techniques being applied to children with minor technical adjustments. More and more, surgeons are implanting intraocular lenses in younger children. One of the most widely reported technologic advances in 2004-2005 was the use of hydrophobic acrylic intraocular lenses in children. Predicting axial growth, and refractive change that accompanies it, is one of the major remaining challenges for the long-term care of children who have had cataract surgery. SUMMARY: Automation and intraocular lenses have helped to provide better anatomic and functional outcome for cataract surgery in children. Two major challenges in the coming years will be to find a way to obviate invasive procedures like posterior capsulotomy and vitrectomy and to study the growth of eyes in a well designed prospective study that will help to design new intraocular lens power calculation formulas specifically suited for children's eyes.