Paola Valente

Iontophoretic transepithelial corneal cross-linking to halt keratoconus in pediatric cases: 15-month follow-up.

Purpose: To report the results 15 months after transepithelial corneal cross-linking by iontophoresis of riboflavin performed in pediatric patients affected by keratoconus. Methods: Fourteen eyes of 14 pediatric patients [mean age 13 ± 2.4 (SD) years; range, 10–18 years] were treated. Riboflavin solution was administered by iontophoresis for 5 minutes, and then UVA irradiation (10 mW/cm2) was performed for 9 minutes. The corrected distance visual acuity measured as decimal number, spherical equivalent, refractive astigmatism, simulated K, corneal coma, spherical aberration, and high-order aberrations for 5.0-mm pupil and the thinnest point were measured preoperatively and 3, 6, 12, and 15 months postoperatively. The endothelial cell density was evaluated. The paired Student t test was used to compare data during the follow-up. Results: Fifteen months after the procedure, the corrected distance visual acuity improved from 0.7 ± 1.7 to 0.8 ± 1.8 (P = 0.005). Spherical equivalent and refractive astigmatism as well as topographic and aberrometric data did not show significant changes. Also, the mean thinnest point and the endothelial cell density remained unchanged. The optical coherence tomography showed a nonhomogeneous but deep hyperreflective band with a fading effect extending through the anterior 180 &mgr;m of the cornea. No side effects were recorded. Conclusions: Transepithelial collagen cross-linking by iontophoresis, unlike other transepithelial techniques, seems to halt pediatric keratoconus progression over 15 months. However, we did not record significant improvement in higher-order aberrations and topographic indices.

Femtosecond Laser and Big-Bubble Deep Anterior Lamellar Keratoplasty: A New Chance

Purpose. To report the 12-month follow-up after big-bubble deep anterior lamellar keratoplasty (DALK) assisted by femtosecond laser that we have called IntraBubble. Methods. A 60 kHz IntraLase femtosecond laser (Abbott Medical Optics) firstly created a 30° angled intrastromal channel to insert the air injection cannula, 50 μ above the thinnest corneal site measured by Sirius Scheimpflug camera (CSO, Firenze, Italy), then performed a full lamellar cut 100 μ above the thinnest corneal point, and from the same corneal depth, created a mushroom incision. The lamella was removed, and the smooth cannula of Fogla was inserted into the stromal channel and air was injected to achieve a big bubble. The follow up is 12 months, and sutures were removed by the 10th postoperative month in all patients. Best Corrected Visual Acuity (BCVA), spherical equivalent and, by Sirius Scheimpflug camera (CSO, Firenze, Italy) keratometric astigmatism were evaluated. Results. All procedures were completed as DALK except 2 converted to PK because an inadvertent intraoperative macroperforation occurred. Mean postoperative BCVA was 0.8, mean spherical equivalent was -3.5 ± 1.7 D, and mean keratometric astigmatism was 4.8 ± 3.1 D. Conclusion. The femtosecond laser could standardize the big-bubble technique in DALK, reducing the risk of intraoperative complications and allowing good refractive outcomes.

Laser welding in penetrating keratoplasty and cataract surgery in pediatric patients: Early results

Purpose To evaluate the efficacy of diode laser welding to close corneal wounds in penetrating keratoplasty (PKP) and cataract surgery in pediatric patients. Setting Ophthalmology Department, Bambino Gesù Children’s Hospital, Rome, Italy. Design Prospective observational study. Methods Patients had surgery for congenital cataract (Group 1) or femtosecond laser–assisted PKP (Group 2). The surgery was followed by corneal wound closure using diode laser welding of the stroma. In Group 1, no standard suturing was used. In Group 2, the donor button was sutured onto the recipient using 8 single nylon sutures or a 10‐0 nylon running suture (12 passages). Laser welding was then used as an adjunct to the traditional suturing procedure. Results Group 1 comprised 7 eyes (7 patients; mean age 8.1 years ± 5.3 [SD], range 1 to 15 years) and Group 2, 5 eyes (5 patients; mean age 10.6 ± 3.3 years, range 6 to 15 years). The adhesion of the laser‐welded tissues was perfect; there were no collateral effects, and restoration of the treated tissues was optimum. Seidel testing showed no wound leakage during the follow‐up. Postoperative astigmatism did not change significantly from the first day after cataract surgery and shifted moderately 3 months after PKP. Conclusion Laser welding of corneal tissue appeared to be safe and effective in children for whom a sutureless surgical procedure is important to reduce the use of anesthesia for suture management, prevent endophthalmitis, and improve the antiamblyopic effect. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Big-bubble deep anterior lamellar keratoplasty assisted by femtosecond laser in children.

Abstract To report the early results of big-bubble deep anterior lamellar keratoplasty assisted by femtosecond laser in children. Five eyes of 5 pediatric patients were enrolled in the study; 3 had keratoconus and 2 corneal opacities. An IntraLase 60 KHz femtosecond laser (Abbott Medical Optics, Inc) was used to create mushroom incisions on both donor and recipient corneas. All patients were evaluated for best-corrected visual acuity, spherical equivalent, refractive astigmatism, keratometric astigmatism, mean K value, and corneal thinnest point. The big bubble was always achieved, and all eyes were treated successfully without intraoperative complications. The follow-up was of 10 months. At 10 months (at least 3 months after complete suture removal), the mean postoperative best-corrected visual acuity was 20/30 (range, 20/25 to 20/30), mean spherical equivalent was −1.8 ± 1.2 diopters (D) (range, −0.25 to 1.25 D), mean refractive astigmatism was 1.8 ± 1.4 D (range, 0 to 4.0 D), mean keratometric astigmatism was 5.1 ± 2.1 D (range, 3.5 to 8.59 D), mean K value was 46.2 ± 0.8D, and mean corneal thinnest point was 581 ± 46 &mgr;m (range, 511–638 &mgr;m). Our early findings suggest that the big-bubble technique in deep anterior lamellar keratoplasty assisted by femtosecond laser is safe and effective also in pediatric patients in the attempt to decrease the rejection percentage, improve the refractive outcome, and then provide an antiamblyopic effect.

Posterior pole retinal thickness in ocular hypertension and glaucoma: early changes detected by hemispheric asymmetries.

To evaluate retinal thickness at the posterior pole of the fundus in ocular hypertension (OHT) and open-angle glaucoma (OAG), and to correlate morphometric findings with visual sensitivity as determined by automated perimetry. Methods:One randomly selected eye from 41 patients with clinical diagnosis of OHT (n = 25) or early to moderate OAG (n = 16) and 16 age-matched normal controls was examined. Retinal thickness was measured by Retinal Thickness Analyzer (RTA), acquiring 5 pre-defined scans covering the central 20° of the fundus. RTA average thickness and thickness profile data, including hemispheric asymmetries calculated as relative (superior/inferior and nasal/temporal) or absolute (vertical and horizontal, ie, independent of which hemisphere was thinner) parameters, were calculated. For each eye, white-on-white Humphrey 30-2 visual field results were analyzed, in addition to standard global indices, by quantifying perimetric sensitivities for regions of the posterior pole corresponding to those sampled by the RTA. Results:On average, central retinal thickness was reduced (P < 0.05) in OAG compared with OHT or normal control eyes. Vertical hemispheric absolute thickness asymmetry was increased (P ≤ 0.01) in OAG eyes compared with the other groups. Horizontal hemispheric absolute thickness asymmetry was increased (P < 0.01) in both OHT and OAG eyes, compared with control eyes. At least one of the RTA parameters was altered in 13 of 25 OHT (52%) and 12 of 16 OAG eyes (75%), most frequently involving thickness asymmetries. In OAG, but not OHT eyes, superior/inferior asymmetry was positively (r = 0.69, P < 0.01) correlated with the corresponding asymmetry in perimetric sensitivity. Conclusions:The RTA can reveal increased hemispheric thickness asymmetries in both OHT and OAG eyes. In OAG eyes thickness asymmetries are associated with corresponding perimetric asymmetries. The findings in OHT eyes suggest that localized anatomic and functional damage to inner retina may not develop in parallel early in the disease process.

Corneal arcus as first sign of familial hypercholesterolemia

Figure 2. Corneal arcus is separated from the limbus by a thin ring of clear cornea (named “lucid interval of Vogt”). A 4-year-old boy was referred for investigation after his parents noticed the presence of a grayish ring parallel to the limbus of both eyes. His past medical history was unremarkable. His father was affected by familial hypercholesterolemia, which was responsive to statin therapy. The ophthalmologic evaluation described a corneal arcus separated by a 1-mm lucid interval (Figures 1 and 2). Blood exams revealed marked low-density lipoprotein hypercholesterolemia (530 mg/dL), suggesting a diagnosis of familial hypercholesterolemia. Corneal arcus, also named “arcus lipoides” or “arcus corneae,” is a white discoloration of the peripheral cornea near the corneoscleral limbus. There is a thin clear section separating the arcus from the limbus known as the lucid interval of Vogt. Arcus deposits tend to start at 6 and 12 o’clock and fill in until becoming completely circumferential. It develops in association with hyperlipidemia as a result of lipid deposition in the deep corneal stroma and the limbal sclera. Its prevalence increases with age. Corneal arcus should be differentiated from other lipid metabolisms affecting the cornea, such as lecithin-cholesterol acyltransferase deficiency deficiency, “fish eye” disease, or Tangier disease. n

Sporadic retinoblastoma and pilocytic astrocytoma: A rare association of two tumors

An increased risk of second neoplasms is well known for longterm retinoblastoma (RB) survivors, particularly for patients affected by hereditary RB and/or treated with radiotherapy.[1–6] CNS tumors are relatively unusual, accounting for about 10% of all second neoplasm; they are mainly associated with radiation treatment and are mostly meningiomas.[3–5,7–8] A 29-month-old previously healthy female underwent enucleation for a monolateral RB, classified as group E, according to the Linn Murphree classification.[9] The histology confirmed RB. Due to the presence of massive choroidal invasion and a retrolaminar invasion of the optic nerve, the child received four courses of chemotherapy based on carboplatin plus etoposide. At diagnosis, the CNS MRI showed alterations in the pre-thalamic region, which were considered due to perinatal asphyxia. Family history was unremarkable. Molecular analysis of RB1 on peripheral blood using a next-generation sequencing approach with the MiSeq platform (Illumina) and multiple ligation-dependent probe assay did not reveal any point mutation or intragenic rearrangement. Investigation of mosaicism was also conducted with a mosaic rate detection of about 5% (unpublished data) without any significant result. Comparative genomic hybridization array showed a normal profile without pathogenic copy number variations. Screening for other cancer predisposition syndromes, such as Li-Fraumeni syndrome, was negative. Moreover, the child had no clinical evidence of neurofibromatosis type I. At 15 months from RB diagnosis, a routine brain MRI showed a lesion localized at the left internal globus pallidus, adjacent to the internal capsule. After 3 months, the lesion showed an increased volume (Fig. 1A and B) and biopsy showed a pilocytic astrocytoma. After 14 months, MRI showed a further local progression in the absence of any clinical symptoms (Fig. 1C and D). A second biopsy confirmed the initial diagnosis. Finally, the child was treated with bevacizumab plus irinotecan for 1 year, achieving a partial response. At 66 months from RB diagnosis and 18 months after discontinuation of bevacizumab/irinotecan, the child is alive with a stable tumor size. This case presents a few peculiar characteristics. The time interval between RB and the occurrence of the CNS lesion was short: the two tumors being almost synchronous. A thalamic lesion was evident at diagnosis of RB and was at that time considered to be due to neonatal asphyxia. Probably, the astrocytic tumor was already present and confused with result of perinatal asphyxia. The occurrence of second tumors earlier than 5 years from the diagnosis of RB is quite rare, raising the suspicion of brain RB relapse/metastasis. That possibility was excluded by the proven astrocytic histology that can be considered a benign tumor. Moreover, the tumor was localized in the pre-thalamic region, an unusual site for a pediatric brain cancer. Surprisingly, none of the main risk factors associated with second tumor—mainly second malignant neoplasms—were identified in this patient, namely radiotherapy and the hereditary form of RB. Considering the peculiar site and the short time interval between the development of the two tumors, an alternative common mechanism could be hypothesized, although the family history was negative for tumors and Li-Fraumeni syndrome was excluded. Intriguingly, both the retina and globus pallidus share the same embryological origin from the diencephalic vescicle. Derangement of molecular signaling involved in diencephalic development might have had a role in tumorigenesis resulting in this association. Fig. 1. Central nervous system MRI at time of first (A and B) and second biopsy (C and D). T2W and T1W axial images (T1W after contrast medium administration).

Advantages of a next generation sequencing targeted approach for the molecular diagnosis of retinoblastoma

BackgroundRetinoblastoma (RB) is the most common malignant childhood tumor of the eye and results from inactivation of both alleles of the RB1 gene. Nowadays RB genetic diagnosis requires classical chromosome investigations, Multiplex Ligation-dependent Probe Amplification analysis (MLPA) and Sanger sequencing. Nevertheless, these techniques show some limitations. We report our experience on a cohort of RB patients using a combined approach of Next-Generation Sequencing (NGS) and RB1 custom array-Comparative Genomic Hybridization (aCGH).MethodsA total of 65 patients with retinoblastoma were studied: 29 cases of bilateral RB and 36 cases of unilateral RB. All patients were previously tested with conventional cytogenetics and MLPA techniques. Fifty-three samples were then analysed using NGS. Eleven cases were analysed by RB1 custom aCGH. One last case was studied only by classic cytogenetics. Finally, it has been tested, in a lab sensitivity assay, the capability of NGS to detect artificial mosaicism series in previously recognized samples prepared at 3 different mosaicism frequencies: 10, 5, 1 %.ResultsOf the 29 cases of bilateral RB, 28 resulted positive (96.5 %) to the genetic investigation: 22 point mutations and 6 genomic rearrangements (four intragenic and two macrodeletion). A novel germline intragenic duplication, from exon18 to exon 23, was identified in a proband with bilateral RB. Of the 36 available cases of unilateral RB, 8 patients resulted positive (22 %) to the genetic investigation: 3 patients showed point mutations while 5 carried large deletion. Finally, we successfully validated, in a lab sensitivity assay, the capability of NGS to accurately measure level of artificial mosaicism down to 1 %.ConclusionsNGS and RB1-custom aCGH have demonstrated to be an effective combined approach in order to optimize the overall diagnostic procedures of RB. Custom aCGH is able to accurately detect genomic rearrangements allowing the characterization of their extension. NGS is extremely accurate in detecting single nucleotide variants, relatively simple to perform, cost savings and efficient and has confirmed a high sensitivity and accuracy in identifying low levels of artificial mosaicisms.

Laser welding in penetrating keratoplasty and cataract surgery of pediatric patients: early results

Diode laser welding of ocular tissues is a procedure that enables minimally invasive closure of a corneal wound. This procedure is based on a photothermal effect: a water solution of Indocyanine Green (ICG) is inserted in the surgical wound, in order to stain the corneal tissue walls. The stained tissue is then irradiated with a low power infrared diode laser, delivering laser light through a 300-μm core diameter optical fiber. This procedure enables an immediate closure of the wounds: it is thus possible to reduce or to substitute the use of surgical threads. This is of particular interest in children, because the immediate closure improves refractive outcome and anti-amblyopic effect; moreover this procedure avoids several general anaesthesia for suture management. In this work, we present the first use of diode laser welding procedure in paediatric patients. 5 selected patients underwent cataract surgery (Group 1), while 4 underwent fs-laserassisted penetrating keratoplasty (Group 2). In Group 1 the conventional surgery procedure was performed, while no stitches were used for the closure of the surgical wounds: these were laser welded and immediately closed. In Group 2 the donor button was sutured upon the recipient by 8 single stitches, instead of 16 single stitches or a running suture. The laser welding procedure was performed in order to join the donor tissue to the recipient bed. Objective observations in the follow up study evidenced a perfect adhesion of the laser welded tissues, no collateral effects and an optimal restoration of the treated tissues.

Treatment of homozygous familial hypercholesterolaemia in paediatric patients: A monocentric experience

Background Homozygous familial hypercholesterolaemia is a rare life-threatening disease characterized by markedly elevated low-density lipoprotein cholesterol (LDL-C) concentrations and accelerated atherosclerosis. The presence of double gene defects in the LDL-Receptor, either the same defect (homozygous) or two different LDL-raising mutations (compound heterozygotes) or other variants, identify the homozygous phenotype (HopFH). Apheresis is a procedure in which plasma is separated from red blood cells before the physical removal of LDL-C or the LDL-C is directly removed from whole blood. It is currently the treatment of choice for patients with HopFH whose LDL-C levels are not able to be reduced to target levels with conventional lipid-lowering drug therapy. Design The aim of this study is to report a cohort of six paediatric patients and to evaluate the long term efficacy of combined medical therapy and LDL-apheresis on LDL-C reduction. Methods We collected data from six children with confirmed diagnosis of HopFH (two females and four males; age range at diagnosis 3–8 years, mean 6 ± 1 years) from a single clinical hospital in Italy from 2007 to 2017. Results Clinical manifestations and outcomes may greatly vary in children with HopFH. Medical therapy and LDL-apheresis for the severe form should be started promptly in order to prevent cardiovascular disease. Conclusions Lipoprotein apheresis is a very important tool in managing patients with HopFH at high risk of cardiovascular disease. Based on our experience and the literature data, the method is feasible in very young children, efficient regarding biological results and cardiac events, and safe with minor side-effects and technical problems. We advise treating homozygous and compound heterozygous children as soon as possible.