[Persistent fetal vasculature syndrome--clinical image and diagnostic difficulties]

PURPOSE

The aim of this review is to present cases of clinically differentiated picture of persistent fetal vasculature syndrome--PFVS (also called persistent hyperplastic primary vitreous body--PHPVB) observed in group of infants and children.

MATERIAL AND METHODS

Case records of four children with characteristic changes of posterior form of persistent fetal vasculature syndrome, which were observed on fundus of the eyes, were analyzed retrospectively. Routine ophthalmological examination, genetic, cytogenetic and laboratory tests towards coexisting bacterial, viral and parasitic diseases and congenital anomaly of the eye or chorioretinal neoplastic changes of neonatal period were performed. Ophthalmological changes were archived using Ret-Cam II apparatus (Clarity Medical Systems). Measurement of the axial diameter of the eyes and exclusion coexisting ocular disease by ultrasonography (A-scan US i B-scan US and color Doppler ultrasonography--CDU), were performed.

RESULTS

Different clinical image of posterior form of persistent hyperplastic primary vitreous body was observe in ophthalmological examination. Changes such as fibrovascular tissue connecting optic disc (n. II) with ora serrata of the retina coexisting with retinoschisis, retrolental mass or persistent hyaloid artery were observed. Additionally concomitant features in pathological eyes were: iris hypoplasia, corectopia, microphthalmia, congenital cataract, secondary glaucoma, degeneration or retinoschisis and intrvitreous haemorrhage. Strabismus, nystagmus and heart disease in the form of persistent fetal circulation were associated with ophthalmological changes. Inflammatory and genetically determined diseases were excluded in differential diagnosis.

CONCLUSIONS

The diagnosis of persistent hyperplastic primary vitreous body (PHPVB) was confirmed by characteristic clinical symptoms and results of the additional research. Suggestion of recognition of this syndrome (PHPVB) as well as persistent fetal vasculature syndrome (PFVS) should be implemented diagnostics towards other optic and systemic development defects.

Heparan sulfate deficiency in periocular mesenchyme causes microphthalmia and ciliary body dysgenesis

The heparan sulfate (HS) is a component of proteoglycans in the extracellular matrix and on cell surfaces, modulating developmental processes. The aim of this study is to investigate whether the defect of HS in the periocular mesenchyme impairs ocular morphogenesis. First, using Protein 0-Cre transgenic mice, we ablated Ext1, which encodes an indispensable enzyme for HS synthesis, in the developing periocular mesenchyme. The expression of Ext1 messenger RNA (mRNA) and HS were observed by RT-PCR and immunohistochemistry, respectively. The phenotypes in the mutant were evaluated by light microscopy and immunohistochemistry for cellular makers. Second, the distribution of the mutant periocular mesenchymal cells was tracked using a Rosa26 Cre-reporter gene. No mutant embryos (Protein 0-Cre;Ext1(flox/flox)) were identified after embryonic day 14.5 (E14.5). RT-PCR showed that an intense band amplified from Ext1 was observed in cDNAs from the control periocular mesenchymal cells at E13.5; however, the band for Ext1 was hardly detectable in cDNA from the mutant embryo, indicating that the mRNA was missing in the mutant periocular mesenchyme at E13.5. The HS expression was disrupted in the periocular mesenchyme of the mutant ocular tissues. The HS deficiency resulted in microphthalmia with reduced axial lengths, lens diameters, and vitreous sizes compared with the littermate eyes. The mutant embryos showed agenesis of the anterior chamber, where cells expressing Cre recombinase were distributed. Moreover, the mutants showed phenotypic alterations in the neural ectoderm including dysgenesis of the presumptive ciliary body and agenesis of the optic nerve head. These findings demonstrate that HS in the periocular mesenchyme plays a critical role in normal ocular morphogenesis, indicating reciprocal interactions between the periocular mesenchyme and the neural ectoderm.

Bilateral Complete Isolated Cryptophthalmos: A Case Report

Cryptophthalmos is a condition of congenital eyelid malformation most commonly accompanied by syndactyly, urogenital anomalies, and cognitive impairments as in Fraser syndrome. We report on a patient with characteristic features consistent with autosomal dominant bilateral complete isolated cryptophthalmos. This patient represents only the sixth documented case of bilateral complete isolated cryptophthalmos. Defining characteristics of this variety are discussed, including bilateral central dimpling over the globes, normal eyebrow growth, and the absence of cognitive impairment. We introduce phenotypic features that distinguish bilateral isolated cryptophthalmos from other forms and discuss its relatively favorable prognosis.

On the pathology of the ciliary sulcus

The so-called ciliary sulcus of the posterior chamber of the eye is the place of fixation for some of the posterior chamber lenses. It is only recently that this borderline between the iris root and the ciliary processes gained more interest among clinical ophthalmologists. Little is known on tissue reactions in ocular diseases at this very location. Possible reactions are presented based on the material of the Department of Ocular Pathology of the University Eye Hospital München. The main result of this study is the finding of marked fibrovascular proliferative reactions in inflammatory diseases, and vascular proliferations in diabetic and postthrombotic neovascular glaucoma. It is suggested that such proliferations might be the source of intraocular bleeding after posterior chamber lens implantation.

Genotype and phenotype correlations in congenital glaucoma: CYP1B1 mutations, goniodysgenesis, and clinical characteristics

PURPOSE

To determine whether there is a correlation among mutations in the cytochrome P4501B1 gene (CYP1B1), the degree of angle dysgenesis observed histologically, and disease severity in congenital glaucoma.

DESIGN

Interventional case series.

METHODS

Direct DNA sequencing was used to screen six unrelated children with congenital glaucoma, each set of parents, and all siblings for CYP1B1 mutations. Specimens of the anterior chamber angle obtained at trabeculectomy were examined histologically to identify abnormalities of the aqueous outflow pathway. CYP1B1 mutations were correlated with both the degree of angle dysgenesis and the patients' disease severity (age at diagnosis, difficulty in achieving intraocular pressure [IOP]) control.

RESULTS

Four (66.7%) of the six patients were compound heterozygotes for mutations in the CYP1B1 gene. Seven of the eight CYP1B1 mutations were identified, including two novel mutations (R117P, C209R) and five others previously described (G61E, R368H, R390H, E229K, 4340delG). The cases were divided on the basis of histological phenotype into categories of (1) severe goniodysgenesis highlighted by the agenesis of the canal of Schlemm (two patients), (2) moderate goniodysgenesis characterized by the presence of a band of collagenous tissue (CT) in the trabecular meshwork (TM) and/or the juxtacanalicular tissues (JXT) (three patients), and (3) mild goniodysgenesis with deposition of a mucopolysaccharide material in the JXT (one patient). CYP1B1 mutations were identified in both cases of severe angle dysgenesis and two of three cases of moderate dysgenesis. Disease severity closely correlated with the degree of angle dysgenesis.

CONCLUSIONS

Most patients in our cohort had compound heterozygous CYP1B1 mutations. Specific CYP1B1 mutations may be associated with severe or moderate angle abnormalities.

Genotype and phenotype correlations in congenital glaucoma

PURPOSE

To determine whether there is a correlation among mutations in the cytochrome P450 1B1 gene (CYP1B1), the degree of angle dysgenesis observed histologically, and disease severity in congenital glaucoma.

METHODS

Direct DNA sequencing was utilized to screen six unrelated children with congenital glaucoma, each set of parents, and all siblings for CYP1B1 mutations. Specimens of the anterior chamber angle obtained at trabeculectomy were examined histologically to identify abnormalities of the aqueous outflow pathway. CYP1B1 mutations were correlated with both the degree of angle dysgenesis and the patient's disease severity (age at diagnosis, difficulty in achieving intraocular pressure control).

RESULTS

Four of the six patients (66.7%) were compound heterozygotes for mutations in the CYP1B1 gene. Seven of the eight CYP1B1 mutations were identified, including two novel mutations (R117P, C209R) and five others previously described (G61E, R368H, R390H, E229K, 4340delG). The cases were divided based on histological phenotype into categories of (1) severe goniodysgenesis highlighted by the agenesis of Schlemm's canal (two patients), (2) moderate goniodysgenesis characterized by the presence of a band of collagenous tissue in the trabecular meshwork and/or the juxtacanalicular tissues (three patients), and (3) mild goniodysgenesis with deposition of a mucopolysaccharide material in the juxtacanalicular tissue (one patient). CYP1B1 mutations were identified in both cases of severe angle dysgenesis and two of three cases of moderate dysgenesis. Disease severity closely correlated with the degree of angle dysgenesis.

CONCLUSION

The majority of cases in the cohort had compound heterozygous CYP1B1 mutations. Specific CYP1B1 mutations may be associated with severe or moderate angle abnormalities.

[Persistent hyperplastic primary vitreous--developmental anomaly of the eye in children]

Persistent hyperplastic primary vitreus in children continues to be a diagnostic and therapeutic challenge for ophthalmologists. It can occur in isolation, in association with other ocular disorders and rarely as a part of systemic disorder. Characteristic features include microphthalmic eye, white vascularized retrolental tissue with or without a persistent hyaloid artery, centrally dragged ciliary processes, an anteriorly shifted and (or) swollen lens, and varing degrees of lenticular opacification. PHPF is the most common associaton with unilateral cataracts. Differential diagnosis and functional effect of treatment are discussed.

Ultrasound biomicroscopic findings in aniridia

PURPOSE

To describe the ultrasound biomicroscopic features of eyes with aniridia.

DESIGN

Observational case series.

METHODS

Nineteen eyes of 10 patients with aniridia (six males and four females) ranging in age from 3 months to 53 years (21.0 +/- 16.4, mean +/- SD), and 50 normal subjects (30 men and 20 women) ranging from 16 to 56 years (31.1 +/- 13.2) were evaluated. Ultrasound biomicroscopic findings were recorded in the 3-, 6-, 9-, and 12-o'clock directions. Adult patients (aged 16 years or older) with aniridia were compared with the age-matched controls.

RESULTS

Ultrasound biomicroscopy (UBM) detected extremely tiny irises in all eyes with aniridia. The eyes with aniridia showed significantly smaller values than the controls in ciliary body length (4.49 +/- 0.63 versus 5.79 +/- 0.44 mm, P <.001, unpaired Student t test), ciliary body thickness (0.75 +/- 0.17 versus 1.24 +/- 0.22 mm, P <.001), iris root thickness (0.47 +/- 0.14 versus 0.61 +/- 0.07 mm, P <.001), scleral-ciliary process angle (31.7 +/- 3.26 versus 43.1 +/- 4.48 degree, P <.001), and anterior chamber depth (1.99 +/- 0.43 versus 2.94 +/- 0.34 mm, P <.001). In the aniridia eyes, there was a significantly positive correlation between iris thickness and ciliary body thickness (Pearson r = 0.829, P =.001).

CONCLUSION

Ultrasound biomicroscopic imaging demonstrated that not only iris hypoplasia but also ciliary body hypoplasia exist in aniridia. Anterior inclination of the ciliary process was also found, which was thought to be at least partly responsible for the shallow anterior chamber.

Lack of type XVIII collagen results in anterior ocular defects

Mice lacking type XVIII collagen have defects in the posterior part of the eye, including delayed regression of the hyaloid vasculature and poor outgrowth of the retinal vessels. We report here that these mice also have a fragile iris and develop atrophy of the ciliary body. The irises of Col18a1-/- mice can be seen to adhere to the lens and cornea. After the pupils begin to function, the double layer of epithelial cells separates at the apical cell contacts, leading to defoliation of its posterior pigment epithelial cell layer, and extracellular material begins to accumulate in the basement membrane zones of the iris. In contrast to the iris epithelia, where no clear signs of cellular atrophy were detected, the lack of type XVIII collagen resulted in atrophy of the pigmented epithelial cells of the ciliary body, and there were also ultrastructural abnormalities in the basement membrane zones. These changes did not lead to chronically elevated intraocular pressures, however. Our results indicate that type XVIII collagen is needed for the integrity of the epithelial basement membranes of the iris and the ciliary body and that its gene should therefore be taken into account as a new potential cause of anterior segment disorders in the eye.

Age-dependent iris abnormalities in collagen XVIII/endostatin deficient mice with similarities to human pigment dispersion syndrome

PURPOSE

Collagen XVIII is expressed in ocular basement membranes (BMs) and inactivating mutations cause Knobloch syndrome, with several ocular abnormalities. In this study we investigated ocular structures in collagen XVIII/endostatin (Col18a1(-/-))-deficient mice to elucidate the role of this extracellular matrix component in the eye.

METHODS

Eyes of Col18a1(-/-) and control mice were examined by light and transmission electron microscopy, laser scanning ophthalmoscopy, and fluorescence angiography. Immunohistochemical analysis of neuronal, epithelial, and immune cells in the eye was performed with antibodies against established cell markers.

RESULTS

Col18a1(-/-) mice showed a disruption of the posterior iris pigment epithelial (IPE) cell layer with release of melanin granules. The BM of the posterior IPE was attached to the lens and the nonpigmented epithelium of the ciliary body, which was flattened in mutant mice. In aged mutant mice a severe thickening of the stromal iris BM zone was found, and pigmented cells migrated out of the iris and covered the retina along the inner limiting membrane (ILM), sometimes penetrating into the retina. These cells resembled iris clump cells, and immunohistochemistry demonstrated that they were macrophage-like cells. Furthermore, morphologically abnormal retinal vasculature was seen by fluorescence angiography.

CONCLUSIONS

The abnormalities in the iris and ciliary body of Col18a1(-/-) mice demonstrate an important role of collagen XVIII for the function of ocular BMs. The absence of this collagen alters the properties of BMs and leads to severe defects in the iris, showing striking similarities to human pigment dispersion syndrome. In addition, loss of collagen XVIII creates changes that allow clump cells to migrate out of the iris. These cells have not been well characterized previously. In the current study we showed that they are macrophage-like cells and are able to penetrate the ILM in mutant mice. The disease mechanism of human pigment dispersion syndrome is not well understood, but Col18a1(-/-) mice may serve as a model and demonstrate the potential importance of alterations in extracellular matrix components in this disease.

[Complications of a voluminous congenital ciliary body cyst]

BACKGROUND

Multiple cysts of iris and ciliary body may cause many complications such as acute or chronic angle closure glaucoma.

PATIENT

We present a boy with multiple congenital cysts of the iris pigment epithelium and a voluminous cyst of the unpigmented ciliary body epithelium of the right eye. This resulted in lenticular astigmatism, concomitant strabismus divergens and subsequently to anisometropia. The voluminous cyst (8 x 12 mm in diameter) was folded around the lens, reached the optic axis and resulted in displacement of the lens and contact between the iris and the corneal endothelium from 6.30 to 11. After puncture and partial resection of the cyst at the age of 8 months the boy developed a subcapsular multivesicular cataractic clouding of the temporal lens and a progredient myopia (up to - 14.0/- 2.0/0 degrees ); in contrast the left eye was hyperopic (+ 3.5/- 3.75/0 degrees ). The lens was subluxated superonasally due to congenital damage of the zonular fibres. Because development of visual acuity seemed limited by these determinants (20/200 at the right eye), cataract surgery with posterior capsulorhexis, anterior vitrectomy, and implantation of a capsular tension ring and posterior chamber intraocular lens was performed at the age of nearly five. Actually, there is an orthotropia, best corrected visual acuity in the distance of 20/32 in the right and 20/20 in the left eye; binocular vision is somewhat restricted.

CONCLUSION

Usually congenital cysts are clinically not very relevant; occasionally surgical intervention is required to ensure adequate development of visual acuity.

High-frequency ultrasonography findings in persistent hyperplastic primary vitreous

PURPOSE

To identify anatomic correlates in eyes with persistent hyperplastic primary vitreous (PHPV) by using high-frequency ultrasonography.

METHOD

Three main groups of patients were studied by means of high-frequency ultrasonography over a 19-month period. Group I included 9 eyes of 9 patients with newly diagnosed unilateral PHPV. Group II included 4 eyes of 4 patients with unilateral PHPV that had been previously surgically treated. Group III included 22 eyes and was a control group of patients without PHPV. This group consisted of the 5 contralateral normal eyes of 5 patients with unilateral PHPV in the fellow eye, both eyes of one patient with uncomplicated unilateral cataracts, the affected eye of one patient with unilateral uncomplicated cataract, the affected eye of one patient with isolated retinal coloboma, and 13 normal eyes of 7 young adults. Group I and II patients also had B-scan ultrasonography performed and had any intraoperative findings noted.

RESULTS

Characteristic features of PHPV, such as centrally dragged ciliary processes and swollen anteriorly displaced lens, were observed only in those eyes with PHPV. A new echographic finding of a double linear echo was observed in the region of the pars plana or plicata only in eyes with PHPV. This finding was confirmed intraoperatively to be consistent with a thickened adherent anterior hyaloid face and not to be an anteriorly inserted peripheral retina.

CONCLUSION

High-frequency ultrasound can be reliably used to distinguish characteristic features of PHPV. To our knowledge this is the first such description of the use of high-frequency ultrasonography in PHPV eyes. Furthermore, the presence of a thickened adherent anterior hyaloid face may help explain the well-recognized complications of peripheral retinal tears and retinal detachments during and after surgical intervention.

Haploinsufficiency of the transcription factors FOXC1 and FOXC2 results in aberrant ocular development

Anterior segment developmental disorders, including Axenfeld-Rieger anomaly (ARA), variably associate with harmfully elevated intraocular pressure (IOP), which causes glaucoma. Clinically observed dysgenesis does not correlate with IOP, however, and the etiology of glaucoma development is not understood. The forkhead transcription factor genes Foxc1 (formerly Mf1 ) and Foxc2 (formerly Mfh1 ) are expressed in the mesenchyme from which the ocular drainage structures derive. Mutations in the human homolog of Foxc1, FKHL7, cause dominant anterior segment defects and glaucoma in various families. We show that Foxc1 (+/-)mice have anterior segment abnormalities similar to those reported in human patients. These abnormalities include small or absent Schlemm's canal, aberrantly developed trabecular meshwork, iris hypoplasia, severely eccentric pupils and displaced Schwalbe's line. The penetrance of clinically obvious abnormalities varies with genetic background. In some affected eyes, collagen bundles were half normal diameter, or collagen and elastic tissue were very sparse. Thus, abnormalities in extracellular matrix synthesis or organization may contribute to development of the ocular phenotypes. Despite the abnormalities in ocular drainage structures in Foxc1 (+/-)mice, IOP was normal in almost all mice analyzed, on all genetic backgrounds and at all ages. Similar abnormalities were found in Foxc2 (+/-)mice, but no disease-associated mutations were identified in the human homolog FKHL14 in 32 ARA patients. Foxc1 (+/-)and Foxc2 (+/-)mice are useful models for studying anterior segment development and its anomalies, and may allow identification of genes that interact with Foxc1 and Foxc2 (or FKHL7 and FKHL14 ) to produce a phenotype with elevated IOP and glaucoma.

LMX1B, a LIM homeodomain class transcription factor, is necessary for normal development of multiple tissues in the anterior segment of the murine eye

Proper development of the anterior segment of the mammalian eye is critical for normal ocular function. Indeed, several congenital syndromes associated with anterior segment anomalies can lead to impaired vision and glaucoma. One such syndrome is nail patella syndrome (NPS), caused by haploinsufficiency for the LIM-homeodomain transcription factor LMX1B. Although mutations in LMX1B cosegregate with NPS, whether these mutations cause the glaucoma associated with NPS is not known. Here, we provide evidence that the LIM-homeodomain transcription factor lmx1b is an essential regulator of murine anterior segment development. Mice that are homozygous for a targeted mutation of lmx1b display iris and ciliary body hypoplasia, and cornea stromal defects. In addition, two cDNAs normally downregulated in presumptive cornea, mf1 and mfh1, exhibit persistent expression, while keratocan, a keratin sulfate proteoglycan expressed by keratocytes, is not detected in mutant corneas. Moreover, ultrastructural examination of homozygous mutants indicates that corneal collagen fibrillogenesis is perturbed. Taken together, our studies suggest a developmental etiology for glaucoma in NPS patients and highlight lmx1b as an essential regulator of anterior segment morphogenesis and patterning. genesis 26:15-25, 2000.

Familial Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss: a possible new genetic syndrome

OBJECTIVE

To describe the clinical and ocular histopathological findings in multiple members of a family with congenital Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss.

METHODS

We performed a retrospective review of the medical charts and the ocular histopathological material of multiple members of a family.

RESULTS

Congenital Axenfeld-Rieger anomaly and glaucoma were inherited by both the proband and her male half-sibling from a phenotypically positive father and 2 different phenotypically negative mothers, suggesting an autosomal dominant inheritance. The proband's male half-sibling and her father also had atrial septal defects and sensorineural hearing loss. The proband's paternal grandmother had severe glaucoma. Histopathological analysis of blind, painful eyes removed from the proband's father and paternal grandmother showed incomplete development of the anterior chamber angle with iris stromal hypoplasia, prominent posterior embryotoxon with iris adhesions, and abnormal position and insertion of the ciliary muscles.

CONCLUSIONS

This is the first description of coexisting Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss in multiple members of a single family. The iris, trabecular meshwork, and large portions of the cardiac intraventricular septum all arise from neural crest anlagen, thus supporting the notion that anterior segment dysgenesis represents a developmental disorder of the neural crest.

[Bilateral congenital mydriasis with accommodation failure]

In the literature congenital mydriasis is described as a very rare condition and explained as a result of isolated aplasia of the iris sphincter muscle. Aplasia of the ciliary muscle was assumed to cause congenital accommodation insufficiency. A case of congenital mydriasis with lack of accommodation is presented. The first ophthalmological check-up was 2 weeks after surgery for a persistent ductus arteriosus Botalli. The girl was 15 weeks old. Her parents had watched her dilated pupils since birth. The diameter of both pupils was 6.5 mm. They did not react to light, lid closure, or conjunctival administration of pilocarpine solutions up to 1%. A refractive error of OD +3.0 D and OS +2.5 D was measured by retinoscopy. The hypermetropia was also uninfluenced by topical locarpine 1%. Two drops of pheylephrine 2.5% caused additional pupillary dilatation of 0.5 mm. Besides the lack of accommodation and pupillary constriction, all ocular findings were regular. No chromosomal abnormalities were found. No further cases of pupillary disorders are known in the family. These findings can only result from the lack of cholinergic sensitivity or aplasia of the pupillary sphincter and ciliary muscle. The infant was supplied with bifocals and sunglasses. The near correction was spontaneous. At the age of 15 months there was a grating acuity of 20/80, which is in the normal range, as measured by preferential looking.

Spherophakia, nanophthalmia, hypoplastic ciliary body and glaucoma in brachydactyly-associated syndromes

Three juvenile patients showing a systemic disorder associated with small stature, brachydactyly and glaucoma were discovered to have spherophakia and a nanophthalmic axial length of the eye between 20.29 and 21.26 mm. According to clinical and radiological criteria only one patient was classified as having Marchesani syndrome; one patient suffered from an acrofacial disorder, and the third displayed typical ocular signs of Rieger syndrome. Pupillary block mechanism had led to glaucoma in all three patients. Despite iridectomy and trabeculotomy, two of them had unregulated intraocular pressure (IOP) and showed partial angleblock by progressive anterior synechiae after surgery. Ultrasonographic biomicroscopy revealed in all cases considerable hypoplasia of the ciliary body. We conclude that the clinical combination of spherophakia and brachydactyly is not necessarily limited to Marchesani syndrome. In the wide range of brachydactyly-associated syndromes an ophthalmic examination should always be performed in order to rule out ocular complications such as spherophakia and secondary glaucoma. We could not confirm Marchesani's hypothesis of a hyperplastic ciliary body in the spherophakia-brachydactyly syndrome, considering our nanophthalmic eyes. Pressure-reducing surgery in eyes with spherophakia and nanophthalmia seems to run a high risk of inducing an extensive formation of anterior synechiae.

Opaque eyes developed in transgenic mice with T-cell receptor delta gene

PURPOSE

During the generation of transgenic mice (TGs) introduced with mouse T-cell receptor delta (TCR delta) gene, the authors found a TG line with corneal opacity that coincided with the presence of the transgene. The authors investigated the pathogenesis and molecular mechanisms of this corneal opacity in this line.

METHODS

The pathologic features and pathogenesis of the corneal opacity in TGs were examined histologically using transmission and scanning electron microscopy, as well as light microscopy. DNA and RNA blot analyses were performed to examine the copy number and the expression of the transgenes, respectively.

RESULTS

Histologically, edema of the corneal epithelium and adhesion of the iris to the cornea were observed in adult TGs. In the developmental analysis, the authors first observed relative hypoplasia of the ciliary body on day 18 of gestation and dysgenesis of the anterior chamber angle from postnatal day 2. Corneal opacity was observed from postnatal day 8, coinciding with the histologic vesicular change of the epithelium. No inflammation was observed through its life. In the sublines that have different copy numbers of the transgene, the occurrence of the opacity depended on the copy number of the transgene. Expression of the transgene in the thymus was consistent with the number of the introduced transgene.

CONCLUSION

In a TCR delta TG line, the overexpression of transgenes coincided with abnormal development of the ocular anterior segment and the corneal opacity. Pathogenesis is described, and possible molecular mechanisms are discussed.

A common pathway for developmental glaucomas

In a clinicopathologic study of ten patients, utilizing a modified trabeculectomy technique for acquisition of histologic specimens, a high insertion of the iris was observed in four types of developmental glaucoma. A survey of the literature revealed additional developmental disorders with this abnormality of the anterior chamber angle. The common defect is believed to arise from a developmental arrest during the third trimester of gestation of tissues derived from cranial neural crest cells. The mechanism by which this developmental defect leads to aqueous outflow obstruction may, in some cases, be a paradoxical collapse of the trabecular meshwork and Schlemm's canal in response to contraction of the ciliary musculature, while other patients may have additional developmental abnormalities in the aqueous outflow system as the possible mechanism of glaucoma.

Bilateral optic nerve abnormalities associated with a 4-10 chromosomal translocation

A neonate with ocular abnormalities and a chromosomal aberration is described. The patient demonstrates a typical choroidal coloboma involving the iris ciliary body and choroid of the right eye, bilateral optic pits-coloboma and a karyotype with a 4-10 chromosomal translocation. Although a random occurrence of the ocular phenomena and the chromosomal aberration cannot be ruled out, it is appealing to speculate about the possible association of the ocular colobomata and the chromosomal translocation harbored by this patient.

Hamartomatous adenoma of the nonpigmented ciliary epithelium arising in iris-ciliary body coloboma. Light and electron microscopic observations

A 2 1/2-year-old boy had a slowly enlarging mass at the site of a typical iris-ciliary body coloboma for 2 years. The mass was excised partially by iridocyclectomy. By light microscopy, the tumor cells were embedded in a rich mucoid stroma that contained abundant hyaluronidase-sensitive acid mucopolysaccharides. By electron microscopy the tumor showed light and dark cells with interdigitating cell membranes, desmosomes, gap junctions, multilaminar basement membrane, and numerous extracellular collagen fibrils that resembled vitreous fibrils. We believe that the tumor represents a hamartomatous (congenital) adenoma of the nonpigmented ciliary epithelium rather than a conventional (acquired) adenoma, since it developed precisely within a colobomatous defect of the iris and ciliary body.

Colobomata of the iris, ciliary body and choroid in an infant with oesophago-tracheal fistula and congenital heart defects. An unknown malformation complex

A malformation pattern, not previously reported consisting of microphthalmia, uveal coloboma, oesophago-tracheal fistula and congenital heart defects is presented. The phaenotypical similarity and difference from previously reported cases are discussed.

Complex sporadic colobomata

Sporadic colobomata may be associated with a variety of secondary changes, and these have been classified and discussed with special reference to unusual findings published during recent years. Clinically some cases may appear to be neoplastic, and pathological examination may be important in demonstrating their true nature. A malformation apparently not previously reported is described.

Eye findings in the 13 trisomy syndrome

The gross and microscopic eye findings in the first historic case of the 13-trisomy syndrome included: severe microphthalmia, coloboma of the ciliary body, cataracts, detached retina, and retinal dysplasia.

[Vitreoretinal dysgenesis. Persistance and hyperplasia of the primitive vitreous body. Treatment]

The authors report five cases of persistant hyperplastic vitreous with four regressive cataracts. An anterior surgery technique is proposed with keratotomy and excision of the cataract and the persistant hyperplastic vitreous. Anatomic result is always good; even a visual acuity is possible.

[Intravitreous cyst probably arising from ciliary body epithelium (author's transl)]

A description is given of a pigmented cyst situated within the anterior part of the vitreous body in the otherwise healthy eye of a girl aged 9 years.

Ectopic intraocular lacrimal gland tissue

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