Megaloftalmos anterior: un reto diagnóstico / Anterior megalophthalmos: A diagnostic challenge

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Arginine to Glutamine Variant in Olfactomedin Like 3 (OLFML3) Is a Candidate for Severe Goniodysgenesis and Glaucoma in the Border Collie Dog Breed.

Goniodysgenesis is a developmental abnormality of the anterior chamber of the eye. It is generally considered to be congenital in dogs (Canis lupus familiaris), and has been associated with glaucoma and blindness. Goniodysgenesis and early-onset glaucoma initially emerged in Border Collies in Australia in the late 1990s and have subsequently been found in this breed in Europe and the USA. The objective of the present study was to determine the genetic basis of goniodysgenesis in Border Collies. Clinical diagnosis was based on results of examinations by veterinary ophthalmologists of affected and unaffected dogs from eleven different countries. Genotyping using the Illumina high density canine single nucleotide variant genotyping chip was used to identify a candidate genetic region. There was a highly significant peak of association over chromosome 17, with a p-value of 2 × 10-13 Expression profiles and evolutionary conservation of candidate genes were assessed using public databases. Whole genome sequences of three dogs with glaucoma, three severely affected by goniodysgenesis and three unaffected dogs identified a missense variant in the olfactomedin like 3 (OLFML3) gene in all six affected animals. This was homozygous for the risk allele in all nine cases with glaucoma and 12 of 14 other severely affected animals. Of 67 reportedly unaffected animals, only one was homozygous for this variant (offspring of parents both with goniodysgenesis who were also homozygous for the variant). Analysis of pedigree information was consistent with an autosomal recessive mode of inheritance for severe goniodysgenesis (potentially leading to glaucoma) in this breed. The identification of a candidate genetic region and putative causative variant will aid breeders to reduce the frequency of goniodysgenesis and the risk of glaucoma in the Border Collie population.

Factors influencing pupil behaviour during femtosecond laser assisted cataract surgery.

AIM: Femtosecond laser assisted cataract surgery is associated with pupillary constriction. This study aims to look at patient and surgical factors predisposing to abnormal pupil behaviour during FLACS. METHODS: This prospective observational study included all patients undergoing FLACS in the Princess of Wales Hospital, Bridgend, UK between February and June 2017. Pupils were measured at three time points; immediately before and after laser pre-treatment, and at the start of surgery. Pupil behaviour during surgery was noted in descriptive terms, patient demographic, co-morbidities, eye measurements, suction on time, shifting time and laser energy levels were recorded. RESULTS: Seventy-three eyes were included. Average patient age was 74.84 ±â€¯9.1 years. Mean horizontal pupil sizes immediately before and after femto pre-treatment were 7.87 ±â€¯0.87 mm and 7.7 ±â€¯0.89 mm respectively (P < 0.0005). Mean horizontal pupil size at the start of surgery was 6.83 ±â€¯1.43 mm (P < 0.0005). Short capsulotomy-pupil distance (P = 0.01), shallower anterior chamber (P = 0.0012), smaller pre-operative pupil size (P = 0.045) and longer suction on time (P = 0.0019) were significantly associated with intra-operative miosis during FLACS. Sustained mydriasis was observed in eyes in whom topical diclofenac was used within 2 h of surgery. CONCLUSIONS: FLACS can result in significant pupil miosis. Eyes particularly at risk are ones with smaller pre-operative pupils and shallower anterior chambers and those subjected to longer suction on time. Well-timed NSAIDs application could be protective against this phenomenon.

Iridogoniodysgenesis: A Challenging Case.

Iridogoniodysgenesis is a rare autosomal dominant disorder affecting anterior segment of the eye. Fifty percent cases of iridogoniodysgenesis have glaucoma, which is particularly difficult to manage. We report here a case of 40 years old man with this rare disorder, presenting to our glaucoma department. It was characterised by iris hypoplasia and juvenile glaucoma. To stop fluctuation in his intraocular pressure (IOP) and to save his vision from glaucomatous damage, our team had to do three different surgical procedures, i.e. trabeculectomy with F5U, diode laser cycloablation and aqueous shunt procedure, over a period of 10 months. This case report discusses management of glaucoma in this particular patient and challenges faced during the treatment. Regular follow-up and timely intervention can save such patients from complete blindness. To authors' knowledge, this is the first reported case of iridogoniodysgenesis in Pakistan.

A rare case of cleft number nine associated with atypical cleft number two.

The incidence of the craniofacial cleft is rare ranging between 1.43 and 4.85/100,000 births. Tessier number nine cleft being the rarest, there are a few reports of detailed ophthalmologic examinations performed in them. In this study, 1-day-old female neonate delivered by normal vaginal delivery at term, weighing 1480 g presented with right eye dystopia, cleft extending through the lateral third of the upper eyelid, brow ending at the temporal region, conjunctival congestion, clear cornea 10 mm in diameter, normal anterior chamber, pupil 2 mm reactive to light, clear lens, and normal fundus. Cleft extended downward from the right medial canthus involving the nasal ala and left forearm had an oblique-crease with camptodactyly. We thus report a case of anterior segment abnormality with an oblique craniofacial cleft. The cause of which is unclear, amniotic band syndrome being a possible cause.

Phacoemulsification in anterior megalophthalmos: rhexis fixation technique for intraocular lens centration.

We describe phacoemulsification in both eyes of a patient with anterior megalophthalmos. Surgery in such cases can be challenging because of a deep anterior chamber, enlarged ciliary ring, weakened zonules, and large capsular bag. Phacoemulsification performed through a scleral tunnel resulted in a stable wound. We report the use of anterior optic capture technique (optic within the capsulorhexis margin, haptics in the sulcus) for successful intraocular lens implant centration.

Amniotic bands as a cause of congenital anterior staphyloma.

BACKGROUND: Congenital anterior staphyloma is a rare, complex malformation syndrome of the anterior segment. Only a few reports on associated systemic malformations have been published. We herein present a rare manifestation of congenital anterior staphyloma (CAS) combined with amniotic band disruption syndrome (ABS). PATIENT AND METHODS: Shortly after birth, a massive enlargement of the left eye was observed in a female child. Furthermore, an extensive bilateral congenital cleft lip and cleft alveolar ridge with oblique facial cleft extending into the left medial canthal region, coloboma(s) of the left eyelids, extensive adhesions between lids and eye bulb, as well as circumferential grooves, clubfeet, and terminal transverse defects in both hands and feet were present. Due to severe progression of eye bulb protrusion with thinning of the sclera, enucleation of the left eye was performed at the age of 3 years in order to prevent complications including perforation of the globe and with the aim of improving cosmetic aspects. RESULTS: Histopathological examination of the enucleated eye disclosed findings typical of congenital anterior staphyloma, including massive corneal staphylomatic deformation with superficial vascularization and elapsed corneoscleral margin, destruction of Bowman's layer, absence of Descemet's layer, corneal endothelium, and angle structures. The lens was only partially formed, and had mainly dissolved. The neural retina appeared normal. The optic nerve disc revealed a pronounced excavation. Facial clefts, lid colobomas, congenital constriction bands, and amputation of distal limbs match ABS. This malformation complex develops in early pregnancy, probably prior to 35 days post conception. CONCLUSION: This is the first report on an association of these two rare complex congenital malformations, congenital anterior staphyloma and amniotic band syndrome. The anterior staphyloma was unilateral, and related to facial clefts and lid coloboma in the area adjacent to the anterior staphyloma. Furthermore, the systemic deformities are clearly due to the amniotic bands, and the timing of the development of both complex malformations seems to be similar. All findings suggest that the presence of amniotic bands is a causative factor for all observed abnormalities including anterior staphyloma.

Successful visual rehabilitation in a case of anterior megalophthalmos.

We report a case of 40-year-old female who presented with diminution of vision in both eyes. Ocular evaluation showed presence of bilateral megalocornea with deep anterior chamber, iridodonesis, cataract, and anterior embryotoxon. She was diagnosed with bilateral anterior megalophthalmos. She underwent an uneventful cataract extraction with standard posterior chamber intraocular lens implantation of overall large diameter in the left eye. Zonular dialysis was not evident intraoperatively despite the presence of iridodonesis. Postoperatively the intraocular lens was well centered throughout follow up. This case report reviews this rare disorder and highlights successful visual rehabilitation.

Effect of primary iris and ciliary body cyst on anterior chamber angle in patients with shallow anterior chamber.

OBJECTIVE: To evaluate the prevalence of primary iris and/or ciliary body cysts in eyes with shallow anterior chamber and their effect on the narrowing of the anterior chamber angle. METHODS: Among the general physical check-up population, subjects with shallow anterior chambers, as judged by van Herick technique, were recruited for further investigation. Ultrasound biomicroscope (UBM) was used to detect and measure the cysts located in the iris and/or ciliary body, the anterior chamber depth (ACD), the angle opening distance at 500 µm (AOD500), and the trabecular-iris angle (TIA). A-scan ultrasonography was used to measure the ocular biometry, including lens thickness, axial length, lens/axial length factor (LAF), and relative lens position (RLP). The effect of the cyst on narrowing the corresponding anterior chamber angle and the entire angle was evaluated by the UBM images, ocular biometry, and gonioscopic grading. The eye with unilateral cyst was compared with the eye without the cyst for further analysis. RESULTS: Among the 727 subjects with shallow anterior chamber, primary iris and ciliary body cysts were detected in 250 (34.4%) patients; among them 96 (38.4%) patients showed unilateral single cyst, 21 (8.4%) patients had unilateral double cysts, and 42 (16.8%) patients manifested unilateral multiple and multi-quadrants cysts. Plateau iris configuration was found in 140 of 361 (38.8%) eyes with cysts. The mean size of total cysts was (0.6547 ± 0.2319) mm. In evaluation of the effect of the cyst size and location on narrowing the corresponding angle to their position, the proportion of the cysts causing corresponding angle narrowing or closure among the cysts larger than 0.8 mm (113/121, 93.4%) was found to be significantly higher than that of the cysts smaller than 0.8 mm (373/801, 46.6%), and a significant higher proportion was also found in the cysts located at iridociliary sulcus (354/437, 81.0%) than in that at the pars plicata (131/484, 27.1%). In evaluating the effect of the cyst on the entire anterior chamber angle, the eyes with multiple and multi-quadrants cysts manifested significant narrowing of the entire anterior chamber angle as compared with the eyes without cysts, based on the data analysis in comparison of TIA, AOD500, and gonioscopic grading evaluation. The unilateral single or double cysts in the eyes had no significant effect on narrowing of anterior chamber angle as compared with eyes without cysts. The iris and/or ciliary body cysts did not seem to affect the axial length, ACD, lens thickness, RLP, LAF. CONCLUSIONS: The prevalence of primary iris and ciliary body cyst was 34.4% in the subjects with shallow anterior chamber. The cysts larger than 0.8 mm, locating at iridociliary sulcus, or multiple and extensive cysts were inclined to cause the angle narrowing or closure.

Application of ultrasound biomicroscopy in the planning of cataract surgery in anterior megalophthalmos.

Anterior megalophthalmos, a rare hereditary disorder, is macrocornea (horizontal corneal diameter more than 13 mm) in association with enlarged lens-iris diaphragm and ciliary ring. One of the major challenging issues in the cataract surgery of these patients is preventing intraocular lens (IOL) malposition, because of probable large capsular bag. Several approaches have been selected by previous surgeons, such as, custom-made anterior chamber IOLs. In this study, we show a normal capsular bag diameter despite ciliary ring enlargement, with application of ultrasound biomicroscopy (UMB). We suggest that in cases of anterior megalophthalmos without phacodonesis, UBM could measure the actual size of the capsular bag and obviate the need for further procedures.

Double anterior chamber in a patient with glaucoma and microspherophakia.

We report the case of a 16-year-old woman with microspherophakia and secondary open angle glaucoma. The patient presented with a membrane dividing the anterior chamber into two segments without edema or Descemet's membrane detachment. Slit lamp biomicroscopy, Pentacam, and specular microscopy images were obtained. Double anterior chamber is primarily found in patients with anterior chamber anomalies when there is no history of surgery or trauma.

Alteration of the serine protease PRSS56 causes angle-closure glaucoma in mice and posterior microphthalmia in humans and mice.

Angle-closure glaucoma (ACG) is a subset of glaucoma affecting 16 million people. Although 4 million people are bilaterally blind from ACG, the causative molecular mechanisms of ACG remain to be defined. High intraocular pressure induces glaucoma in ACG. High intraocular pressure traditionally was suggested to result from the iris blocking or closing the angle of the eye, thereby limiting aqueous humor drainage. Eyes from individuals with ACG often have a modestly decreased axial length, shallow anterior chamber and relatively large lens, features that predispose to angle closure. Here we show that genetic alteration of a previously unidentified serine protease (PRSS56) alters axial length and causes a mouse phenotype resembling ACG. Mutations affecting this protease also cause a severe decrease of axial length in individuals with posterior microphthalmia. Together, these data suggest that alterations of this serine protease may contribute to a spectrum of human ocular conditions including reduced ocular size and ACG.

Maternal treatment with opioid analgesics and risk for birth defects.

OBJECTIVE: We examined whether maternal opioid treatment between 1 month before pregnancy and the first trimester was associated with birth defects. STUDY DESIGN: The National Birth Defects Prevention Study (1997 through 2005) is an ongoing population-based case-control study. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIS) for birth defects categories with at least 200 case infants or at least 4 exposed case infants. RESULTS: Therapeutic opioid use was reported by 2.6% of 17,449 case mothers and 2.0% of 6701 control mothers. Treatment was statistically significantly associated with conoventricular septal defects (OR, 2.7; 95% CI, 1.1-6.3), atrioventricular septal defects (OR, 2.0; 95% CI, 1.2-3.6), hypoplastic left heart syndrome (OR, 2.4; 95% CI, 1.4-4.1), spina bifida (OR, 2.0; 95% CI, 1.3-3.2), or gastroschisis (OR, 1.8; 95% CI, 1.1-2.9) in infants. CONCLUSION: Consistent with some previous investigations, our study shows an association between early pregnancy maternal opioid analgesic treatment and certain birth defects. This information should be considered by women and their physicians who are making treatment decisions during pregnancy.

A case of oculodentodigital dysplasia syndrome with novel GJA1 gene mutation.

PURPOSE: To report a case of oculodentodigital dysplasia syndrome (ODDD) with a heterozygous mutation in GJA1 (connexin 43) gene. METHODS: A 9-year-old girl visited our hospital complaining of visual disturbances. The patient had microphthalmia, a small nose with hypoplastic alae nasi, and syndactyly. Visual acuity with prescribed glasses improved to 0.5 (1.2) OU 2 months after the first visit. She was satisfied with the new glasses and the improvement in visual acuity. Genomic DNA was extracted from leukocytes of the patient's peripheral blood in accordance with standard procedures, after obtaining parental informed consent. We amplified GJA1 exon 2 from her genomic DNA by the PCR method, and sequenced the product using the dye terminator method. RESULTS: S5C (c. 13A > T), a novel mutation in exon 2 of GJA1, was found in the patient. The parents had no mutation of GJAI, nor was there any sign of abnormality in other family members. No similar mutation could be found in the 50 genotyped normal subjects in the control group. CONCLUSIONS: A novel GJA1 mutation was detected in a Japanese ODDD patient. Glaucoma complications associated with ODDD have already been reported. Careful long-term monitoring and treatment are also necessary.

Reduced corneal thickness and enlarged anterior chamber in a novel ColVIIIa2G257D mutant mouse.

PURPOSE: The purpose of this study was the morphologic and genetic characterization of the novel eye size mutant Aca23 in the mouse. METHODS: The eyes of the mutants were characterized in vivo by optical low-coherence interferometry, Scheimpflug imaging, and funduscopy. Visual acuity was examined using a virtual optomotor system. Morphology was studied by histology, in situ hybridization, and immunohistochemistry. Linkage analysis was performed using genomewide scans with single nucleotide polymorphisms and microsatellite markers. RESULTS: Aca23 is a new semidominant eye size mutant that was discovered in an ENU mutagenesis screen. The phenotype includes increased anterior chamber depths, extended axial lengths, and reduced thickness of corneal layers. Aca23 was mapped to chromosome 4. A G-->A point mutation was identified at cDNA position 770 of Col8a2 encoding collagen VIII alpha2. The transition results in a G257D amino acid exchange affecting a highly conserved glycine residue in the collagenous domain. Proliferation of corneal endothelium, eye fundus, and visual acuity are not affected. CONCLUSIONS: The mouse mutant Aca23 described here offers the first point mutation of the Col8a2 gene in the mouse. The results of this study suggest that a functional collagen VIII alpha2 is essential for the correct assembly of the Descemet's membrane and for corneal stability. Aca23 might be used as a novel model for keratoglobus.