Partial Cataract Research Articles

Ocular biometry of infants and young children with congenital cataract

Objective: To understand the developmental characteristics of early ocular biological parameters in patients with congenital cataract. Methods: Retrospective case series study. The ocular biometry data such as the axial length, corneal curvature, anterior chamber depth and central corneal thickness of 169 patients under 3 years old who were diagnosed with congenital cataract in Eye Hospital of Wenzhou Medical University (Hangzhou Branch) from June 2016 to June 2020 were reviewed, and they were analyzed by 3 age groups. There were 87, 41, and 41 patients in three age groups, 1 to 6 months, 7 to 12 months, and 13 to 36 months, respectively; 108 patients with bilateral affected eyes and 61 patients with unilateral affected eyes were included; 84 patients with partial opacity lens and 85 patients with total opacity lens were included. The right eyes of the patients with bilateral congenital cataract were selected for analysis. Statistical analysis of ocular biological parameters between groups was performed using the independent samples t-test and paired samples t-test. Statistical analysis of the relationship between age in months and biological parameters was performed using the Pearson's correlation test. Results: The axial length at the age of 1 to 6 months in the affected eyes of patients with bilateral cataract was (17.59±1.19) mm, it was shorter than the affected eyes of patients with unilateral cataract [(18.18±1.34) mm], and the axial length in the affected eyes of patients with unilateral cataract were shorter than the healthy eyes [(19.01±0.93) mm]. At the age of 7 to 12 months, the axial length in the affected eyes of patients with unilateral cataract [(19.89±0.74) mm] was shorter than the healthy eyes [(20.48±0.43) mm]. The differences were statistically significant (t=-2.06, -5.62, -3.47, all P<0.05). The axial length in the affected eyes with partial opacity at the age of 1 to 6 months was shorter than those with total opacity [(17.43±1.14) mm vs. (18.06±1.29) mm; t=-2.38, P=0.020]. The difference in axial length (affected eyes vs. healthy eyes) was significantly correlated with the age in months in partial cataract (r=0.53, P=0.001). The corneal curvature in the affected eyes of patients with unilateral cataract was flatter than the healthy eyes at the age of 7 to 12 months [(42.41±1.82) D vs. (43.19±1.96) D; t=-2.29, P=0.038], but was steeper at the age of 13 to 36 months [(43.36±2.32) D vs. (42.55±1.88) D; t=2.17, P=0.043]. The anterior chamber depth in the affected eyes of patients with unilateral cataract was less than the healthy eyes at the age of 1 to 6 months [(2.44±0.37) mm vs. (2.58±0.33) mm; t=-2.08, P=0.048].The central corneal thickness in the affected eyes of patients with unilateral cataract was thicker than the healthy eyes both at the age of 1 to 6 months and 7 to 12 months [(555.26±46.95) μm vs. (541.85±40.78) μm, (542.93±27.63) μm vs. (530.93±30.36) μm; t=3.82, 2.26; P=0.001, 0.040]. Conclusions: Congenital cataracts maybe affect the early development of axial length, corneal curvature, anterior chamber depth and central corneal thickness. The degree of lens opacity maybe affecte the early axial length development. The axial length in eyes with partial opacity can be shorter than those with total opacity before the age of 6 months, and thereafter gradually outnumbered the latter.

Refractive Lens Exchange Surgery in Early-Onset High Myopia Patients With Partial Cataract.

PurposeBy reporting clinical characteristics and retinal image quality before and after refractive lens replacement surgery in early-onset high myopia (eoHM) patients presenting with partial cataract, we emphasized the need for an objective way to grade the severity of partial cataracts.MethodsThis retrospective, consecutive case series included six Chinese patients (nine eyes). Analysis of previous medical records, visual acuity, optometry, retinal image quality, and axial length (AXL) before surgery and after surgery was performed.ResultsFive females and one male (nine eyes) with a mean (± SD) age of 11.6 ± 7.9 years (range: 4–25 years) were included in this study. The preoperative spherical power ranged from −7.5 to −42 D. The mean follow-up time was 36 months (range: 24–48 months). Phacoemulsification was followed by in-the-bag implantation of intraocular lens. For patients who were under 6 years old, posterior capsulotomy + anterior vitrectomy were performed simultaneously. All surgeries were uneventful and no postoperative complications occurred during the entire follow-up period. All patients’ uncorrected visual acuity improved by ≥2 lines postoperatively(Snellen acuity). LogMAR best-corrected visual acuity was improved at 24-month (P = 0.042) and endpoint (P = 0.046) follow-ups. Modulation transfer function cutoff frequency (MTFcutoff) and objective scatter index (OSI) was significantly improved at 12-month (P = 0.025, P = 0.038), 24-month (P = 0.005, P = 0.007) and endpoint (P = 0.005, P = 0.008) follow-ups. Postoperative AXL remained stable during 2–4 year follow-ups (P > 0.05).ConclusionRefractive lens replacement surgery is safe and effective for improving functional vision in eoHM patients presenting with partial cataract. Retinal image quality could provide a useful and objective way to facilitate partial cataract severity evaluation and surgery decision making.

Gender differences in surgical case volume among ophthalmology trainees.

The number of females in ophthalmology has steadily increased over recent decades. The aim of this study was to evaluate whether there is a difference in procedural volume and cataract surgery between male and female trainees in the Royal Australian and New Zealand College of Ophthalmologists (RANZCO). A longitudinal retrospective review of de-identified surgical RANZCO trainee logbook data from 2008 to 2020 was undertaken. Data from 241 trainee logbooks were analysed for: location of training, gender, date of commencement of training, maternity/paternity leave status, number of surgeries observed, assisted, supervised and unsupervised. Surgical cases were grouped as: (1) all surgical cases; (2) complete cataract cases and (3) partial cataract cases. Among 241 trainees (40.7% females), 197 263 procedures were performed. Total surgical volume was 21.1% lower at 4 years for females (median 665.5 vs. 843.5; p=0.036). Completed cataract surgery was 21.5% lower at 18 months (median 87.5 vs. 111.5; p=0.022) and 41.7% lower at 4 years (median 216 vs. 369; p < 0.001). Interrupted training was significantly more common in females (30.6% vs. 0.7%; p < 0.001). However, linear regression analysis did not identify parental leave or duration as a significant predictor for number of completed cataracts (p=0.206). Complication rate was not different between males and females (p=0.35). Female trainees completed 41.7% fewer cataract operations at the end of their training compared to male counterparts with the gap widening between years 1 and 4 of training. The current data demonstrates that female and male RANZCO trainees are not receiving equivalent operating experiences.

Vitrectomy combined with posterior scleral reinforcement for high myopic macular retinoschisis

Objective To investigate the clinical efficacy of vitrectomy combined with internal limiting membrane peeling and posterior scleral reinforcement for the treatment of high myopic macular retionschisis. Methods The data of 37 eyes of 37 patients with high myopia and macular splitting who were treated in our hospital from Mar. 2014 to Feb. 2017 were analyzed retrospectively. All patients were treated with posterior scleral reinforcement combined with vitrectomy, internal limiting membrane peeling and intravitreal injection of air. Among them partial cataract patients were treated with phacoemulsification and intraocular lens implantation. The follow-up time was 12 months. Results After operation, the retinoschisis was completely closed in 37 eyes. The thickness of central macular retina at 3 months after operation was significantly lower than that before operation (P<0.05). The best corrected visual acuity at 6 months postoperatively was significantly higher than preoperatively(P<0.05), and the visual acuity at 12 months after operation was higher than that at 6 months after operation (P<0.05). The axial length at 6 months after operation was significantly shorter than that preoperatively(P<0.05), and the axial length at 12 months after operation was shorter than that at 6 months after operation (P<0.01). Transient high intraocular pressure occurred in 2 eyes. No secondary surgery treated or other complication occurred. Conclusion The clinical efficacy of posterior scleral reinforcement combined with vitrectomy and internal limiting membrane peeling for the treatment of high myopic macular retionschisis is good. Key words: Reinforcement, posterior sclera; Retinopathy; Myopia, high; Splitting, macula

ОСОБЕННОСТИ ЗРИТЕЛЬНОГО ВОСПРИЯТИЯ У ПАЦИЕНТОВ С ПРЕСБИОПИЕЙ В ЗАВИСИМОСТИ ОТ ВИДА ИНТРАОКУЛЯРНОЙ КОРРЕКЦИИ

Purpose. To assess the long-term results of presbyopia correction in patients with primary cataract depending on type of implantable IOLs.Material and methods. A profound study of visual functions and assessment of visual quality of 90patients (mean age 63.3±1.2years) with partial cataracts and presbyopia. The studies were conducted before surgery and in late post-operative period after bilateral cataract phacoemulsification with implantation of different models IOLs that provide a high visual acuity in distance and at close range. Results. Bilateral implantation of monofocal IOLs for monovision principle leads to a significant increase in far visual acuity of leading the eye and near visual acuity of slave eye. However, patients need long-term adaptation to artificial anisometropia. As a result of bilateral implantation of accommodating IOLs a significant improvement in visual acuity at distance and near occurs. Surgical treatment provides best visual quality of patients up to 6 months after surgery. In period from 12 to 24months after surgery, there was a decrease of visual functions as a result of fibrosis of capsular bag. The correction of presbyopia by creating a multifocal optical system as a result of bilateral multifocal refractive IOL implantation leads to a stable improvement of visual acuity at far and close distance. But thus the contrast sensitivity deteriorates, especially in low- and high-frequency ranges.Conclusion. Intraocular correction of presbyopia is a highly effective method of treatment, allowing obtaining high visual acuity in distance and at close range. However, the results depend on chosen strategy of intraocular correction.

Cataractes congénitales : correction de l’aphaquie par lentilles de contact rigides

To describe follow-up and evaluate functional results of rigid gas-permeable contact lens wear for the correction of aphakia in infants after surgery for congenital cataract. This retrospective study was performed on 23 eyes of 17 children (12 boys and five girls), between three days and 36 months of age (median 3.5 months), undergoing cataract extraction without primary intraocular lens implantation and fitted only with Menicon(®) Z material contact lenses. Initial fitting visits included history and family education. Subsequent examinations were performed at eight days, 15 days, 1 month, 6 months and 1 year. The four main parameters studied were fit characteristics, ease of manipulation, ocular integrity and lens integrity. Concurrently, functional results (visual acuity, oculomotor balance) and various prognostic factors (associated pathology, age at time of surgery, cataract density, unilaterality versus bilaterality, postoperative complications) were evaluated. Rigorous systematic amblyopia rehabilitation was performed. At the one-month exam, 60% of parents demonstrated proficiency with manipulating the lens. On one-year follow-up, three cases of failure were attributable to difficulties with lens manipulation. At one year, one infectious complication was detected. The lens material demonstrated good resistance to breakage (9% at one month) and only a mild tendency toward deposits (few or no deposits in 95% of cases at 1 month). With regard to visual outcome, among the children old enough to cooperate, visual acuity was better than 3/10 for nine out of 12 eyes, of which five eyes were 10/10. With regard to alignment, we noted 12 cases (70.6%) of strabismus postoperatively (ten esotropia, two exotropia). The factors predictive of good visual acuity correlated with those described in the literature: partial cataract, bilateral cataract, and absence of postoperative oculomotor disturbance. The characteristics of rigid gas-permeable contact lenses provide safety and efficacy in aphakic infant eyes. They represent an attractive alternative to primary intraocular lens implantation in congenital cataract.

Clinical characteristics, course, and visual prognosis of partial cataracts that seem to be visually insignificant in children

To report the clinical characteristics and visual prognosis of pediatric partial cataracts that seem to be visually insignificant. In this retrospective case series, the morphologic type and etiology, laterality, best-corrected visual acuity (BCVA), progression, and visual prognosis of partial cataracts in children with more than 1 year of follow-up were evaluated. Of 110 children (184 eyes), 74 (67%) had bilateral and 36 (33%) had unilateral cataracts. The most common type of cataract was posterior subcapsular (36%), followed by nuclear (18%) cataracts. The most common etiology was idiopathic (51%), followed by steroid-induced (28%). Cataracts progressed to surgery in 21 eyes (11%). Among these patients, BCVA was 20/38 at final examination (average follow-up 5.1 years). Among those in whom cataracts did not progress, BCVA was 20/28 at final examination (average follow-up 6.1 years). Initial BCVA was better in the nonprogression group than in the progression group (P = 0.04), but final BCVA did not differ between the groups (P = 0.96). Most patients with partial cataracts that seemed to be visually insignificant and were treated without surgery did not progress and showed favorable visual outcomes. In children who had progressive vision loss, surgery was necessary: these patients also had favorable visual outcomes.

Visual results and complications of primary intraocular lens implantation in infants aged 6 to 12 months

To present the visual results and the complications of primary intraocular lens (IOL) implantation in infants aged 6 to 12 months between January 2002 and July 2007. A total of 26 consecutive eyes, of 16 infants with cataract aged 6 to 12 months, were reviewed in the study. All patients had cataract extraction with anterior and posterior capsulorrhexis combined with anterior vitrectomy and primary hydrophobic acrylic IOL implantation. Six infants (six eyes) had unilateral congenital cataract and ten (20 eyes), bilateral cataract. Visual acuity and complications were recorded throughout the 46.4-month mean follow-up (range 22 to 79 months). All eyes had primary IOL implantation. The mean best-corrected visual acuity (logMAR) was 0.98 +/- 0.18,0.50 +/- 0.14 and 0.61 +/- 0.25 for unilateral, bilateral and all eyes respectively at the last follow-up. IOLs were implanted in the capsular bag of 25 eyes (96.2%) and in the sulcus of the remaining one eye (3.8%). Seven eyes (26.9%) developed visual axis opacification (VAO), and four eyes required secondary pars plana vitrectomy (PPV). IOL opacification occurred in one eye 54 months after implantation. Late onset open-angle glaucoma developed in one eye, and required trabeculectomy surgery. The predictors of good best-corrected visual acuity (BCVA) included partial cataract, bilateral cataract, absence of strabismus or nystagmus, and good amblyopic treatment. The greatest annual myopic change (5.15 +/- 2.08 D) was observed during the first 12 months after surgery. In unilateral cases, there was no significant difference in the axial length between the cataractous eye and the fellow normal eye both at the time of surgery (P = 0.891) and final follow-up (P = 0.693). Primary IOL implantation was safe and effective for infantile cataract surgery. Total or unilateral cataract, nystagmus or strabismus, and inadequate amblyopic therapy were predictors of poor BCVA. Significant myopic shifts occurred especially in infants in the first year of surgery. The pseudophakic eye had a similar growth rate, as measured by axial length, to that of the fellow normal eye, in unilateral cases.

Resolution Visual Fields in Children Surgically Treated for Bilateral Congenital Cataract

To evaluate visual acuity (best corrected visual acuity) and peripheral sensitivity, measured by high-pass resolution (HRP) visual fields, in children surgically treated for congenital cataract. Acuity and peripheral sensitivity were recorded from 16 children, aged 10 to 15 years, either surgically treated for bilateral dense cataract before the age of 4.6 months (n = 10) or surgically treated for bilateral partial cataract at ages 4 to 139 months (n = 6). Data from 22 healthy children, mean age 11 years, served as control. The children with cataract had significantly (P < 0.0001) lower decimal acuity in their better eye (median, 0.55; range, 0.1-1.3) than did the control subjects (median, 1.2; range, 1.0-1.6). Five children were visually impaired according to the World Health Organization's definition (i.e., acuity in the better eye <0.3). The children with previous dense bilateral cataract showed significantly lower peripheral sensitivity than did the control subjects (P = 0.004). Significant correlations were observed between acuity and visual field parameters. Dense cataract, even when surgically treated before the age of 4.6 months, causes persistent impairment of spatial vision, both in the fovea and the visual field. The effect on the visual field is less pronounced than that on visual acuity. This finding has to be taken into account when evaluating visual field results in, for example, the diagnosis of glaucoma, a frequent complication after cataract surgery in early infancy.

Paediatric cataract surgery

Bilateral congenital cataract is the most common cause of treatable childhood blindness. Nuclear cataract is usually present at birth and is non-progressive, while lamellar cataract usually develops later and is progressive. Prompt surgery has to be performed in cases with dense congenital cataract: if nystagmus has developed, the amblyopia is unfortunately irreversible. A treatment regime based on surgery within 2 months of life, combined with prompt optical correction of the aphakia and occlusion therapy with frequent follow-up, have been successful in both unilateral and bilateral cases. The surgery ought to include anterior and posterior capsulorexis in all children at the present time. Intraocular lens implantation has been safely performed below the age of 1 year and has also been successfully performed in bilateral cases. Anterior dry vitrectomy should be performed in preschool children to avoid visual axis opacification. Visual axis opacification is the most common complication found after cataract surgery in children. Secondary glaucoma is by far the most sight-threatening complication and is, unfortunately, common in the newborn so lifelong follow-up is essential in these cases.

Resolution visual fields in children surgically treated for congenital cataract

Abstract Purpose: To evaluate best‐corrected visual acuity (BCVA) and high‐pass resolution perimetry (HRP) visual fields in children surgically treated for congenital cataract. Methods: BCVA and HRP was recorded from 10 aphakic children, aged 10‐15 years and surgically treated for bilateral dense cataract before the age of nine months, and from six aphakic children, aged 10‐15 years and surgically treated for bilateral partial cataract at ages between 6 months and 9 years. Twenty‐three healthy children, 11 years of age, served as controls. Results: The aphakic children had significantly (p &lt; 0.0001) lower BCVA in their best eye (range 0.1‐1.3) compared to controls (range 1.0‐1.6). Two aphakic children were visually disabled according to WHO. The children with previous dense bilateral cataract showed significantly (p &lt; 0.05) lower sensitivity in their resolution visual fields (from their best eyes) compared to both controls and children with previous partial cataract. The dense cataract group also showed significantly (p&lt;0.05) smaller difference between the innermost (5 deg) and the outermost (20‐30 deg) eccentricity locations in their visual fields than the other two groups. Conclusions: Dense cataract, even when surgically treated before the age of nine months, causes persistent impairment of spatial vision both in the fovea and the visual field. Partial cataract appears only to reduce visual acuity.

Spectral filters in low‐vision correction

Coloured filters are used to protect the lens, retina and other ocular tissues against the hazard of light damage and to improve the quality of vision mainly in cases of ocular media opacities. Four types of yellow, amber and orange filters have been designed as tinted glasses, shields and colour covering of spectacles. They were tested on 15 adult patients with partial cataract and on 80 children with congenital pathology (i.e. macular hypoplasia, albinism, aphakia after congenital cataract). The majority of the children had nystagmus. The filters with particular spectral characteristics provide reduction of light intensity in the light-damaging range by at least a factor of five. Optimal filters were selected by examination of visual acuity, contrast frequency sensitivity, glare sensitivity and subjective selection by the patients. The effects of filters were: 11-43% increase in corrected visual acuity, 27-34% increase in contrast sensitivity function (CSF) for all frequencies and a marked reduction in glare sensitivity. All patients reported subjective improvement including reduction of photophobia, eye-strain and eye discomfort. It is concluded that coloured filters are able to contribute substantially to rehabilitation of low-vision patients.

Spectral filters in low-vision correction

Coloured filters are used to protect the lens, retina and other ocular tissues against the hazard of light damage and to improve the quality of vision mainly in cases of ocular media opacities.Four types of yellow, amber and orange filters have been designed as tinted glasses, shields and colour covering of spectacles. They were tested on 15 adult patients with partial cataract and on 80 children with congenital pathology (i.e. macular hypoplasia, albinism, aphakia after congenital cataract). The majority of the children had nystagmus. The filters with particular spectral characteristics provide reduction of light intensity in the light-damaging range by at least a factor of five. Optimal filters were selected by examination of visual acuity, contrast frequency sensitivity, glare sensitivity and subjective selection by the patients. The effects of filters were: 11–43% increase in corrected visual acuity, 27–34% increase in contrast sensitivity function (CSF) for all frequencies and a marked reduction in glare sensitivity. All patients reported subjective improvement including reduction of photophobia, eye-strain and eye discomfort. It is concluded that coloured filters are able to contribute substantially to rehabilitation of low-vision patients.

Predictive value of family data for the management of infantile bilateral partial cataract.

To examine the data on outcome of surgery performed over a wide age range in members of a family affected by familial infantile bilateral partial cataract, with the purpose of assessing their predictive value concerning the timing of surgery. A retrospective clinical study was carried out of a family with dominant inheritance of familial infantile bilateral partial cataract. The family spanned four generations and consisted of 53 members, 31 of whom were examined in our department. Of these, 18 were affected. Cataract surgery was performed in 26 eyes of 15 patients, whose ages ranged from 6 to 58 years at the time of operation. As the surgical procedures spanned the years from 1978 to 1996, different techniques were used. In 24 eyes (92%) the post-operative visual acuity was 6/9 or better. One eye achieved 6/12 and another 6/15. In this particular family there was no relationship between the post-operative visual acuity and the age at which surgery was performed. In deciding when to operate on family members with infantile bilateral partial cataract with similar morphology, in addition to the commonly used criteria the family data should also be taken into account. In infants and young children, delaying surgery may allow better development of visual acuity aided by accommodation, stabilisation of binocularity and more precise determination of the power of an intraocular lens. Success of very early surgery in such cases may not be attributable to the timing of the operation.

Evaluation of Lens Opacity: Do I Operate or Not? Why?

The decision whether or not to operate on an infant with a partial cataract is based on the morphology of the lens opacity. Indications of a visually significant opacity include an opacity larger than 3 mm., a posterior cataract, a cataract which is confluent without clear intermediate zones. The ability to visualize retinal detail with a direct ophthalmoscope is also important. In verbal children a visual acuity of 20/70 or worse is usually the guideline for surgery. In some cases, children will present with cataracts which may have been present since early infancy, or even birth. In these patients who present late with presumed congenital cataracts, the question whether to operate or not is often difficult. Signs of a good prognosis include lamellar cataracts, posterior lenticonus, persistent hyperplastic primary vitreous (anterior type), and patients with unilateral cataracts and straight eyes with no strabismus. Even patients with nystagmus may show improvement.

Pars Plicata Lensectomy/Vitrectomy for Developmental Cataract Extraction: Surgical Results

Fifty-two cases of developmental cataracts extracted using the pars plicata lensectomy/vitrectomy technique were reviewed. Eyes with additional ocular anomaly other than microphthalmos were not included. No early complications were detected in a postoperative period ranging from 1.5 to 7 years with a median of 4 years, and late complications were limited to secondary membranes occurring in small eyes. Since secondary membranes occurred only in eyes in which the axial length was less than or equal to 17.4 mm and the corneal diameter was less than or equal to 9.5 mm, we suggest that eyes that are small by the absolute dimensions cited here are at greater risk of developing secondary membranes postoperatively. Small eyes by absolute dimensions should be distinguished from microphthalmic eyes, since the relative term microphthalmic is less predictive of risk of complication than are absolute dimensions. Linear Snellen acuity in 15 patients capable of response ranged as follows: 20/20-20/80 with a median of 20/40 in eyes with partial bilateral cataracts; 20/25-20/80 with a median of 20/50 in eyes with complete bilateral cataracts; 20/30-20/400 with a median of 20/200 in eyes with unilateral partial cataracts; and 20/60-CF with a median of 20/400 in eyes with complete unilateral cataracts. Mean patient ages at surgery were 3 months for those with bilateral complete cataracts, 5 months for those with unilateral complete cataracts, 18 months for those with bilateral partial cataracts, and 25 months for those with unilateral partial cataracts. The earliest possible removal of visually significant opacities must be combined with aggressive postoperative visual rehabilitation to obtain the best possible visual outcome.

Visual Results in Aphakic Children

Sixty-five patients less than 10 years of age had cataract surgery on 99 eyes. The visual prognosis depended on the cataract type and whether the treatment was undertaken during the critical period for development of the fixation reflex. All patients received the same surgical technique, aggressive optical correction, and occlusion therapy, if needed. Partial cataracts were the most frequent and the two largest groups were lamellar and axial. The visual outcome was excellent for the lamellar cataracts, whereas axial cataracts were the most amblyogenic. Obtaining a good visual result demanded an understanding of the complexities of amblyopia.

Visual Results Following Infantile Cataract Surgery

Aspiration and its modifications have been shown to be a superior operative procedure for neonatal, congenital, infantile, and acquired cataracts. However, the visual results obtained in the infantile cataractous eye, whether the opacity is complete or partial, still remain within the same range as the results of other operative techniques reported over the last 3 decades. Adequate visual results often cannot be obtained because of the associated systemic and/or ocular defects or failure of optical and amblyopia treatment. Perhaps increased efforts should be made to perform surgery at even earlier ages in those patients with complete, or in some cases, partial, cataracts in which surgery is contemplated. In children with partial cataracts who are able to function well, the lens should be allowed to remain in place and conservative measures of visual preservation should be undertaken for as long as possible. This allows the eye more time to develop normal visual functions with an intact lens and accommodative mechanisms. It should be stressed again that the sole success or failure of surgery for infantile cataracts cannot always be the visual acuity. The real measure is the child's ability to function successfully in his environment for the remainder of his life.

Congenital hereditary cataract in Cocker Spaniels.

ABSTRACTCases of congenital cataract in red Cocker Spaniels are reported. The investigation comprised clinical, histological and genetic studies. The common feature was bilateral, congenital, partial cataract of non‐progressive nature.Typically the cataract was localized subcapsularly at the anterior pole of the lens. In some cases it was of a more diffuse extent. In a few cases the cataract co‐existed with persisting pupillary membrane, microphthalmia, hypotonia and rotatory nystagmus. Histopathological examination of affected eyes confirmed the clinical findings.The disease appears to be of hereditary nature. The genetic studies on the condition in this breed of dogs showed that the mode of inheritance is presumably complex.

Evaluation of the surgery of congenital cataracts.

IN THE textbooks of ophthalmic surgery very little space has been devoted to a consideration of congenital cataracts. In recent years, however, and especially since the recognition of the rubella cataract, new interest in the subject has developed. Care of congenital cataracts is clearly a matter of first importance, to the community as well as to the patient; and this fact suggested that an attempt to evaluate the various surgical procedures currently in practice might serve a useful purpose. Congenital cataract is usually not discovered until the child is several weeks or months old, and partial cataract which leaves some vision intact may be overlooked for an even longer time. The very narrow pupils of newborn babies, their habit of sleeping a good deal, and their inability to fix very often obscure the fact that they do not see. Certain forms of congenital cataract show a hereditary tendency. Marner¹