Outcomes and complications after phacoemulsification in retinoblastoma patients with cataract after radiation treatment. / Facoemulsificación en pacientes con retinoblastoma y catarata por radioterapia: resultados y complicaciones.

PURPOSE: To describe the visual outcome and complications associated with phacoemulsification in patients with bilateral retinoblastoma (Rb), with lens opacification secondary to external beam radiotherapy. METHODS: A descriptive study was performed on patients with Rb, treated in Federico Gomez Children's Hospital, Mexico, from January 1997 to August 2015, with external beam radiotherapy eye salvaging. Statistical analysis was performed using Stata 10. RESULTS: A total of 15 patients were included. The mean age at phacoemulsification was 7.5 years. Mean preoperative visual acuity was 1.0LogMAR (range 0.4-1.6), and the mean postoperative visual acuity was 0.7LogMAR (range 0.1-1.6). Twelve patients had visual improvement (P<.05). The visual acuity decreased in one patient with vitreous haemorrhage and secondary glaucoma, and 2 patients with exudative maculopathy secondary to radiation. Mean follow up was 46 months and not a single patient showed tumour re-activation. CONCLUSIONS: Cataract surgery produces a statistically significant improvement in visual acuity. These patients have increased risk for eye complications in the mid- and long-term. It is important to conduct a close follow up due to reactivation of tumour.

Illumina next generation sequencing data and expression microarrays data from retinoblastoma and medulloblastoma tissues.

Retinoblastoma (Rb) is a pediatric intraocular malignancy and probably the most robust clinical model on which genetic predisposition to develop cancer has been demonstrated. Since deletions in chromosome 13 have been described in this tumor, we performed next generation sequencing to test whether recurrent losses could be detected in low coverage data. We used Illumina platform for 13 tumor tissue samples: two pools of 4 retinoblastoma cases each and one pool of 5 medulloblastoma cases (raw data can be found at http://www.ebi.ac.uk/ena/data/view/PRJEB6630). We first created an in silico reference profile generated from a human sequenced genome (GRCh37p5). From this data we calculated an integrity score to get an overview of gains and losses in all chromosomes; we next analyzed each chromosome in windows of 40 kb length, calculating for each window the log2 ratio between reads from tumor pool and in silico reference. Finally we generated panoramic maps with all the windows whether lost or gained along each chromosome associated to its cytogenetic bands to facilitate interpretation. Expression microarrays was done for the same samples and a list of over and under expressed genes is presented here. For this detection a significance analysis was done and a log2 fold change was chosen as significant (raw data can be found at http://www.ncbi.nlm.nih.gov/geo/accession number GSE11488). The complete research article can be found at Cancer Genetics journal (Garcia-Chequer et al., in press) [1]. In summary here we provide an overview with visual graphics of gains and losses chromosome by chromosome in retinoblastoma and medulloblastoma, also the integrity score analysis and a list of genes with relevant expression associated. This material can be useful to researchers that may want to explore gains and losses in other malignant tumors with this approach or compare their data with retinoblastoma.

Overview of recurrent chromosomal losses in retinoblastoma detected by low coverage next generation sequencing.

Genes are frequently lost or gained in malignant tumors and the analysis of these changes can be informative about the underlying tumor biology. Retinoblastoma is a pediatric intraocular malignancy, and since deletions in chromosome 13 have been described in this tumor, we performed genome wide sequencing with the Illumina platform to test whether recurrent losses could be detected in low coverage data from DNA pools of Rb cases. An in silico reference profile for each pool was created from the human genome sequence GRCh37p5; a chromosome integrity score and a graphics 40 Kb window analysis approach, allowed us to identify with high resolution previously reported non random recurrent losses in all chromosomes of these tumors. We also found a pattern of gains and losses associated to clear and dark cytogenetic bands respectively. We further analyze a pool of medulloblastoma and found a more stable genomic profile and previously reported losses in this tumor. This approach facilitates identification of recurrent deletions from many patients that may be biological relevant for tumor development.

Temporary morphological changes in plus disease induced during contact digital imaging.

OBJECTIVE: To compare and quantify the retinal vascular changes induced by non-intentional pressure contact by digital handheld camera during retinopathy of prematurity (ROP) imaging by means of a computer-based image analysis system, Retinal Image multiScale Analysis. METHODS: A set of 10 wide-angle retinal pairs of photographs per patient, who underwent routine ROP examinations, was measured. Vascular trees were matched between 'compression artifact' (absence of the vascular column at the optic nerve) and 'not compression artifact' conditions. Parameters were analyzed using a two-level linear model for each individual parameter for arterioles and venules separately: integrated curvature (IC), diameter (d), and tortuosity index (TI). RESULTS: Images affected with compression artifact showed significant vascular d (P<0.01) changes in both arteries and veins, as well as in artery IC (P<0.05). Vascular TI remained unchanged in both groups. CONCLUSIONS: Non-adverted corneal pressure with the RetCam lens could compress and decrease intra-arterial diameter or even collapse retinal vessels. Careful attention to technique is essential to avoid absence of the arterial blood column at the optic nerve head that is indicative of increased pressure during imaging.

Clinical delineation of a patient with trisomy 1q32.qter and monosomy 5p resulting from a familial translocation 1;5.

We describe a patient who had multiple malformations including ventriculomegaly, colpocephaly, corpus callosum, cerebellum and vermix hypoplasia, optic nerve hypoplasia, corneal opacity and congenital heart disease in whom a trisomy 1q32-qter and monosomy 5p derived from a t(1;5)mat was diagnosed by karyotype and FISH analysis. This trisomy/monosomy association has not been previously reported. The familial analysis of the translocation was carried out in four generations and its implications on the phenotype of the patient and genetic counseling are discussed.

Long-term visual results in congenital cataract surgery associated with preoperative nystagmus.

BACKGROUND: Congenital cataracts are the leading cause of preventable blindness in children. The prevalence of this disease is higher in developing countries. The incidence and visual outcome of patients who have undergone congenital cataract surgery in Mexico is not currently known. The purpose of this study is to evaluate the long-term visual results in Mexican children with bilateral congenital cataracts associated with preoperative nystagmus. METHODS: In a tertiary-level hospital, the long-term visual results of 13 children (26 eyes) with bilateral congenital cataracts associated with preoperative nystagmus were evaluated. All patients had at least 5 years of follow-up after surgery, and all patients were subjected to an intentional ophthalmologic examination. Three types of visual function were evaluated: visual acuity, contrast sensitivity vision, and stereoscopic vision. Age at surgery was correlated with visual outcome. Optical rehabilitation and surgical complications were also analyzed. RESULTS: Our group found five patients (38%) with acceptable visual acuity levels. Eight patients (62%) were legally blind according to World Health Organization (WHO) guidelines. Contrast sensitivity vision and stereopsis were severely affected in all patients. We also found a high correlation between timing of surgery, optical rehabilitation, and visual outcome. CONCLUSIONS: Early diagnosis and treatment, in addition to adequate optical rehabilitation, are mandatory for preventing blindness secondary to congenital cataracts in developing countries. The current state of congenital cataract management in Mexico is also examined.

The surgical correction of paralytic strabismus using fascia lata.

OBJECTIVE: To present the results of a new technique designed to restore and maintain alignment, exclusively in the primary position, in patients with paralytic strabismus. METHODS: In five patients (seven eyes, total) with exotropia secondary to third-nerve palsy, we fixated the globe with a strip of fascia lata sutured onto both the medial aspect of the eye and the nasal bone periosteum. We characterized the ocular deviation in the primary position with prism diopters the day before the operation, during the initial 24-hour period, and at subsequent monthly postoperative evaluations. We documented all evaluations with photographs. RESULTS: In all patients, the ocular position improved with the surgery. No further change of the ocular position was noted during the follow-up period, which ranged from 15 to 35 months (mean follow up 22.5 months). All the patients tolerated the collagenous tissue without complications. CONCLUSIONS: This procedure can be a useful addition to the current surgical techniques for management of strabismus secondary to third-nerve paralysis.