Local and systemic toxicity of intravitreal melphalan for vitreous seeding in retinoblastoma: a preclinical and clinical study.

PURPOSE: Intravitreal melphalan is emerging as an effective treatment for refractory vitreous seeds in retinoblastoma, but there is limited understanding regarding its toxicity. This study evaluates the retinal and systemic toxicity of intravitreal melphalan in retinoblastoma patients, with preclinical validation in a rabbit model. DESIGN: Clinical and preclinical, prospective, cohort study. PARTICIPANTS: In the clinical study, 16 patient eyes received 107 intravitreal injections of 30 µg melphalan given weekly, a median of 6.5 times (range, 5-8). In the animal study, 12 New Zealand/Dutch Belt pigmented rabbits were given 3 weekly injections of 15 µg of intravitreal melphalan or vehicle to the right eye. METHODS: Electroretinogram (ERG) responses were recorded in both humans and rabbits. For the clinical study, ERG responses were recorded at baseline, immediately before each injection, and at each follow-up visit; 82 of these studies were deemed evaluable. Median follow-up time was 5.2 months (range, 1-11). Complete blood counts (CBCs) were obtained on the day of injection at 46 patient visits. In the animal study, ERG responses were obtained along with fluorescein angiography, CBCs, and melphalan plasma concentration. After humane killing, the histopathology of the eyes was evaluated. MAIN OUTCOME MEASURES: For the clinical study, we measured peak-to-peak ERG amplitudes in response to 30-Hz photopic flicker stimulation with comparisons between ERG studies before and after intravitreal melphalan. For the animal study, we collected ERG parameters before and after intravitreal melphalan injections with histopathologic findings. RESULTS: By linear regression analysis, over the course of weekly intravitreal injections in retinoblastoma patients, for every additional injection, the ERG amplitude decreased by approximately 5.8 µV. The ERG remained stable once the treatment course was completed. In retinoblastoma patients, there were no grade 3 or 4 hematologic events. One week after the second injection in rabbits, the a- and b-wave amplitude declined significantly in the melphalan treated eyes compared with vehicle-treated eyes (P<0.05). Histopathology revealed severely atrophic retina. CONCLUSIONS: Weekly injections of 30 µg of melphalan can result in a decreased ERG response, which is indicative of retinal toxicity. These findings are confirmed at an equivalent dose in rabbit eyes by ERG measurements and by histopathologic evidence of severe retinal damage. Systemic toxicity with intravitreal melphalan at these doses in humans or rabbits was not detected.

Primary undifferentiated large cell carcinoma of the lacrimal gland.

PURPOSE: To report a unique case of primary undifferentiated large cell carcinoma (LCCA) of the lacrimal gland, a tumor not previously described in the ophthalmic literature. DESIGN: Single interventional case report. PARTICIPANTS: A patient affected by undifferentiated LCCA of the lacrimal gland. METHODS: A 65-year-old white man with a 3-month history of a painful mass in the left lacrimal gland fossa underwent an incisional biopsy that revealed a "high-grade" epithelial malignancy. Systemic workup revealed enlargement of the regional lymph nodes, and subsequently the patient underwent extended exenteration with clear histologic margins and radical neck lymphadenectomy followed by adjunctive radiotherapy. Fifteen months postoperatively, the patient is alive and well without evidence of local recurrence or metastatic disease. MAIN OUTCOME MEASURES: Treatment result, evidence of local recurrences or distant metastasis, and follow-up. RESULTS: Histologic examination revealed a poorly circumscribed tumor composed of large cells invading orbital fat, lateral rectus muscle, and peripheral nerves. The surrounding orbital bone was infiltrated, but the surgical margins were clear. The cell population was composed of large cells (>30 µm) with eosinophilic cytoplasm and ovoid and irregular nuclei containing a prominent nucleoli and coarse chromatin. The cell borders were well defined. Mitosis figures were abundant, and Ki-67 was positive in more than 60% of the cells. The cells were arranged in cords and trabeculae or irregular sheets of discohesive cells. The immunophenotype analysis showed positivity for cytokeratin but negative cytokeratin 20 stains, which is considered a distinctive feature of LCCA. CONCLUSIONS: Undifferentiated LCCAs are rare tumors of the major salivary glands, especially the parotid gland. Primary undifferentiated LCCA of the lacrimal gland has never been reported in the literature. Differential diagnosis must include a primary source in another organ. Given the aggressive nature of the tumor, radical surgery followed by radiotherapy is recommended, but evidence-based indications regarding the preferred line of treatment are lacking and the prognosis remains guarded. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Early histologic and functional study of radial optic neurotomy outcomes in normal rat eyes.

BACKGROUND: Radial optic neurotomy (RON) has been proposed as a treatment for central retinal vein occlusion. However, it is still under debate whether RON would be an adequate treatment or a dangerous procedure, and persuasive animal studies are lacking. The aim of this study was to analyze the early histologic and functional outcomes of RON in normal rat eyes. METHODS: Radial optic neurotomy was performed by cutting into the optic nerve edge at the nasal hemisphere, while the contralateral eye underwent a sham procedure. The retinal function was assessed by scotopic electroretinography, and the visual pathway was assessed by flash visual evoked potentials. Intraocular pressure was assessed with a tonometer, the pupillary light reflex was measured after exposing eyes to a 30-second light flash, whereas the optic nerve head structure was examined by histologic analysis. RESULTS: In normal rat eyes, RON provoked minor histologic alterations at the optic nerve head level and a transient decrease in the electroretinography. No changes in visual evoked potentials, intraocular pressure, and pupillary light reflex were observed in rat eyes submitted to RON. CONCLUSION: To our knowledge, this is the first study describing the early histopathologic and functional consequences of RON in normal rat eyes.

Sequential in vivo confocal microscopy study of corneal wound healing after cross-linking in patients with keratoconus.

PURPOSE: To evaluate the short- and long-term sequential histological changes of the cornea in vivo after corneal collagen cross-linking (CXL) in patients with keratoconus. METHODS: Eighteen patients with keratoconus (Amsler-Krumeich classification: stages I, II, and III) underwent CXL with riboflavin/ultraviolet A (UVA) in one eye. The corneas were examined preoperatively and within 5 hours, 7 and 14 days, and 1, 3, 6, 9, 12, 18, 24, and 36 months after the procedure using in vivo confocal microscopy. RESULTS: Early changes included edema, superficial nerve loss, cellular modifications, and isolated endothelial damage. At intermediate time points, there was nerve fiber regeneration, increased reflectivity of the extracellular matrix, enlarged keratocytes and extracellular deposits, and remodeling of the endothelial layer (two eyes). At later time points, loss of keratocytes and remodeling of the extracellular deposits were noted. CONCLUSIONS: Although the cornea has no significant tissue modifications clinically after CXL, this study has shown that corneal wounding by riboflavin/UVA collagen CXL induces cellular wound-healing mechanisms and alters the normal structure and cellularity of the cornea for up to 36 months.

One-year follow-up of epithelial corneal cell sheet allografts mounted on platelet poor plasma in rabbits.

PURPOSE: To evaluate the usefulness of epithelial corneal sheets mounted on platelet poor plasma (PPP) for allograft transplantation of rabbits with total limbal stem cell deficiency (LSCD) and to prove its efficacy at 1 year after surgery. METHODS: LSCD was induced in 21 female rabbits by mechanical keratectomy. To configure the grafts, limbal biopsies were taken from male rabbits and cells were cultured on a fibroblast feeder layer grown on clotted autologous PPP. After keratectomy, grafts were sutured over the stroma. Control groups consisted of no implant or an implant of clotted PPP. Rabbits were euthanized at 3 and 12 months. Corneas and cultured sheets were processed for histopathology and immunohistochemistry (K3/12 and K19). Gender analysis was performed at 4 and 7 months. RESULTS: One rabbit had endophthalmitis, and another died of no apparent cause. The rest of the animals treated had no inflammation, showed a stratified epithelium, keratin 3/12 expression, and no expression of keratin 19. At 1 year, seven of eight rabbits showed no LSCD or corneal rejection signs. Y chromosomes were detected at 4 and 7 months postoperatively. All controls showed LSCD signs, erratic epithelium, and minimal cell differentiation; they revealed a slight expression of K3/12 and an expression of K19 in patchy patterns. CONCLUSIONS: Allografts contributed to restoring a healthy eye surface without signs of graft rejection. This technique seems to be a promising procedure for bilateral ocular surface diseases and may be useful for new therapeutic strategies.

Visual loss secondary to orbital apex invasion as the first manifestation of recurrent nasopharyngeal carcinoma.

A 51-year-old white man was referred for evaluation of visual loss in the right eye caused by an apical orbital lesion. His medical history was positive for "lymphoepithelial carcinoma" of the nasopharynx successfully treated with radiotherapy 6 years previously. Cranial CT showed a diffuse orbital mass extending from the pterygopalatine fossa, infiltrating the inferior orbital fissure, the orbital apex, and the cranial cavity. Results from an incisional biopsy of the lesion were consistent with the diagnosis of nasopharyngeal carcinoma, nonkeratinizing lymphoepithelial variant of squamous cell carcinoma. The patient underwent stereotactic radiosurgery, which arrested the tumor progression. Orbitocranial recurrence of nasopharyngeal carcinoma is rare and ocular symptoms may be the first manifestation of the disease.

Epithelial tumors of the lacrimal gland: an update.

PURPOSE OF REVIEW: The goal of this article is to offer an update on the treatment and prognosis of the most common epithelial tumors of the lacrimal gland, report on new pathological entities and offer a review of the classification of lacrimal gland tumors. RECENT FINDINGS: Improvements have been made in the understanding of lacrimal gland lesions with the knowledge that lacrimal gland tumors compare to the more common counterparts of the major salivary glands. Therefore, the WHO's classification of salivary gland tumors has been adapted to the lacrimal gland pathology. Until recently, primary adenocarcinomas of the lacrimal gland were not further subclassified, but they can now be divided into low-grade and high-grade malignancies. The adjunctive use of intra-arterial cytoreductive chemotherapy for the management of adenoid cystic carcinoma is one of the most important advancements on the management of these aggressive tumors. Another important step forward has been taken on carcinoma ex pleomorphic adenoma of the lacrimal gland, which is subclassified into noninvasive carcinoma, with an excellent prognosis after complete excision and invasive carcinoma for which the prognosis is still guarded despite adjunctive radiotherapy. SUMMARY: This article offers an update on diagnosis, classification and treatment of common and rare epithelial lacrimal gland tumors.

Involvement of purinergic P2 receptors in experimental retinal neovascularization.

PURPOSE: The present study was aimed to investigate the expression of purinergic P2 receptors in oxygen-induced retinal neovascularization. METHODS: Immunohistochemistry was used to study the expression of purinergic P2Y2 and P2X2 receptors in the neonatal mouse retina during normal vascular development and after oxygen-induced retinopathy (OIR). The effect of the P2 antagonists, suramin and PPADS, on the extent of oxygen-induced retinal neovascularization was analyzed. RESULTS: In normal mice, the expression of P2Y2 receptors was weak throughout the retina, whereas P2X2 receptor expression was detected in the outer plexiform layer. In mice treated with oxygen, P2Y2 expression was detected in the ganglion and in the nerve fiber layers, whereas P2X2 expression was found in the inner and outer plexiform layers. Oxygen-induced preretinal neovascularization was strongly inhibited by the P2 antagonists, suramin (p<0.05) and PPADS (p<0.05), and this was accompanied by a down-regulation of P2X2 receptor expression in the inner plexiform layer in suramin-treated mice. CONCLUSIONS: The data suggest that purinergic P2 receptors are involved in neovascularization associated with OIR.

Corneal Neovascularization: A Combined Approach of Bevacizumab and Suramin Showed Increased Antiangiogenic Effect Through Downregulation of BFGF and P2X2.

PURPOSE: The objective is to analyze the antiangiogenic mechanism of suramab, a pharmaceutical compound of bevacizumab and suramin, in a rabbit model of corneal angiogenesis. MATERIAL AND METHODS: Corneal neovascularization was induced in four groups of six New Zealand White rabbits by applying a filter paper disk soaked in 1 M Na (OH) on the central cornea. Group one was treated after injury with intravenous suramab at a dose equivalent to 3 mg/kg of bevacizumab and 10 mg/kg of suramin. Group two was treated with intravenous bevacizumab (5 mg/kg). Group three was treated with 10 mg/kg of suramin while the control group received no treatment. Digital photographs were taken at days 9, 15, 21, and 35. Neovessel formation was quantified giving a 0-4 score to each quadrant according to the centripetal growth of the longest vessel (neovessel index, NVI). Animals were sacrificed at day 35. Corneas were processed for histology, immunohistochemistry, and Western-blot using primary antibodies against P2X2, basic fibroblast growth factor (bFGF), LYVE-1, PECAM-1, and vascular endothelial growth factor-A (VEGF-A). RESULTS: Suramab significantly reduced neovessel growth (mean NVI: 4.2) compared to bevacizumab (8.4), suramin (7.22), and control animals (12.2) at 35 days post-injury (p < 0.01). A lower protein expression of P2X2, bFGF, LYVE-1, PECAM-1, and VEGF-A was found in the cornea of suramab animals than in the other groups of animals. CONCLUSIONS: Joint downregulation of bFGF, P2X2, bFGF, and LYVE-1 constitutes a mechanism that induces greater and longer inhibition of corneal angiogenesis. Results might be relevant to ophthalmic care. Ocular administration of suramab is currently being investigated.

Possible neuroprotective role of P2X2 in the retina of diabetic rats.

BACKGROUND: Purinergic receptors are expressed in different tissues including the retina. These receptors are involved in processes like cell growth, proliferation, activation and survival. ATP is the major activator of P2 receptors. In diabetes, there is a constant ATP production and this rise of ATP leads to a persistent activation of purinergic receptors. Antagonists of these receptors are used to evaluate their inhibition effects. Recently, the P2X2 has been reported to have a neuroprotective role. METHODS: We carried out a study in groups of diabetic and non-diabetic rats (N = 5) treated with intraperitoneal injections of PPADS, at 9 and 24 weeks of diabetes. Control group received only the buffer. Animals were euthanized at 34 weeks of diabetes or at a matching age. Rat retinas were analyzed with immunohistochemistry and western blot using antibodies against GFAP, P2X2, P2Y2 and VEGF-A. RESULTS: Diabetic animals treated with PPADS disclosed a much more extended staining of VEGF-A than diabetics without treatment. A lower protein expression of VEGF-A was found at the retina of diabetic animals without treatment of purinergic antagonists compared to diabetics with the antagonist treatment. Inhibition of P2X2 receptor by PPADS decreases cell death in the diabetic rat retina. CONCLUSION: Results might be useful for better understanding the pathophysiology of diabetic retinopathy.

Treatment of Nonmetastatic Unilateral Retinoblastoma in Children.

Importance: Multi-institutional collaborative studies that include large patient populations for the management of retinoblastoma with histopathological risk factors could provide important information for patient management. Objective: To evaluate the implementation of a strategy for the management of nonmetastatic unilateral retinoblastoma in children based on standardized diagnostic and treatment criteria. Design, Setting, and Participants: This single-arm prospective study applied a strategy based on a single-center experience. The setting was a multicenter study in Latin America (Grupo de America Latina de Oncologia Pediatrica [GALOP]). Participants were children with nonmetastatic unilateral retinoblastoma (staged with the International Retinoblastoma Staging System). The study opened on July 1, 2008, and closed on December 31, 2014. Follow-up was updated until June 30, 2017. Interventions: Stage 0 patients (without enucleation) were given conservative therapy without a protocol. Stage I patients (with enucleation and no residual tumor) were divided into a high-risk group (retrolaminar invasion and/or scleral invasion) and a low-risk group (all remaining patients). High-risk children received adjuvant chemotherapy with 4 alternating cycles of regimen 1 (cyclophosphamide [65 mg/kg/d] [plus sodium-2-mercaptoethane sulfonate], idarubicin hydrochloride [10 mg/m2/d], and vincristine sulfate [0.05 mg/kg/d]) and 4 cycles of regimen 2 (carboplatin [500 mg/m2/d, days 1 and 2] and etoposide [100 mg/m2/d, days 1-3]). Low-risk children did not receive adjuvant therapy. Children with buphthalmia received neoadjuvant and adjuvant chemotherapy for a total of 8 cycles. Main Outcomes and Measures: Probability of event-free survival (extraocular relapse and death from any cause were considered events). Results: Among 187 children registered in the study, 175 were evaluable (92 [52.5%] female; median age, 22 months; age range, 3-100 months). Forty-two were stage 0 children, 84 were stage I low-risk children, and 42 were stage I high-risk children; there were 7 children in the buphthalmia group. With a median follow-up of 46 months, the 3-year probability of event-free survival was 0.97 (95% CI, 0.94-0.99), and the probability of overall survival was 0.98 (95% CI, 0.94-1.00). Stage 0 patients had no events, stage I low-risk patients had 1 event (orbital relapse treated with second-line therapy), stage I high-risk patients had 2 events (1 central nervous system relapse and 1 death from sepsis), and the buphthalmia group had 1 event (orbital relapse, followed by central nervous relapse and death). Conclusions and Relevance: Adjuvant therapy may be effective for high-risk unilateral retinoblastoma but is toxic, and neoadjuvant chemotherapy for buphthalmus appears feasible.

Advances in corneal stem-cell transplantation in rabbits with severe ocular alkali burns.

PURPOSE: To evaluate the efficacy of autologous corneal epithelial sheet implantation in restoring transparency of rabbit corneas severely injured by alkaline and the effect of photocoagulation in arresting corneal neovessel ingrowth. SETTING: Ophthalmology Department, School of Biomedical Sciences, Universidad Austral, Buenos Aires, Argentina. METHODS: Limbal stem-cell deficiency (LSCD) was induced in 14 rabbits by alkali burns. A limbal cell biopsy was done in the contralateral eye, and the cells were cultured on a fibroblast feeder layer grown on autologous clotted platelet-poor plasma or commercial fibrin for 21 days. Anterior keratectomy was followed by suturing corneal cell sheets over the stroma. If regrowth of vessels occurred, argon laser photocoagulation was applied to them. Rabbits were killed at 30, 60, 90, 180, and 360 days and the corneas processed for histopathology and inmunohistochemistry. RESULTS: A small (2.5 mm(2)) limbal biopsy achieved stem-cell replication in vitro. Corneal clarity and epithelial defects evolved with a trend toward improvement. There was a significant reduction in corneal neovascularization. Histology showed a multilayered stratified epithelium including several epithelial-like cells with clear cytoplasm in the deepest part. There were no signs of intraepithelial mucin cells on the implanted corneas. Immunohistochemical results showed expression of cytokeratins 3 and 12 in the central corneal epithelium and an absence of cytokeratin 19. CONCLUSIONS: Autologous limbal epithelial cell transplantation improved the corneal surface in eyes with LSCD. Photocoagulation of neovessel ingrowth was effective over the 1-year follow-up. Results may facilitate the application of this technique in patients.

Surface and Orbscan II slit-scanning elevation topography in circumscribed posterior keratoconus.

We used an Orbscan II topography system (Bausch & Lomb) to study anterior and posterior surface abnormalities, keratometry, and topographic pachymetry in a patient with circumscribed posterior keratoconus. This system clearly showed a marked localized paracentral annular elevation in the posterior corneal surface that corresponded to an abrupt decrease in thickness and a slightly localized anterior surface bulge in the anterior float.

Suramab, a novel antiangiogenic agent, reduces tumor growth and corneal neovascularization.

PURPOSE: Oncological and ophthalmological diseases are increasingly treated with antiangiogenic agents. These agents have different intensities and duration of effects that should be considered to choose the most suitable therapy. Our purpose was to evaluate the synergistic effect of two drugs, jointly administered as a pharmaceutical compound, in two animal models. METHODS: Corneal neovascularization was induced in three groups of nine white New Zealand rabbits, applying a filter paper disk soaked in 1 M NaOH on the central cornea (Ormerod et al., Invest Ophthalmol Vis Sci 30:2148-2153, 1989). Group one was treated immediately after injury with intravenous Suramab, compound of Bevacizumab + Suramin, and group two with intravenous Bevacizumab. A third group of non-treated rabbits was included as control group. Digital photographs were taken at days 9, 15, 21, and 35. Neovessel index (NVI) was calculated using the Image J Program. Neovessels formation was quantified and given a score from 0 to 4 to each quadrant according to the centripetal growth of the longest vessel. Colorectal animal model: 6- to 8-week-old male BALB/c mice were inoculated with cancer cells. Seven days after tumor inoculation, four groups of BALB/c mice were treated with intravenous Bevacizumab (n = 9); intravenous Suramin (n = 10); intravenous Suramab (n = 10); and intravenous saline solution (n = 4). Tumor growth was assessed twice weekly by caliper measurement. RESULTS: The NVI was remarkably inferior in the group of rabbits treated with intravenous Suramab compared with controls after 35 days of follow-up. A greater inhibitory effect was obtained with Suramab compared to that obtained with Bevacizumab. Suramab significantly reduced tumor volume and prolonged survival of mice compared to controls. CONCLUSIONS: Suramab strongly reduced neovascularization in a rabbit model of corneal angiogenesis and induced a potent antitumoral effect in mice.

Episcleral implants for topotecan delivery to the posterior segment of the eye.

Purpose. Intravenous or periocular topotecan has been proposed as new treatment modality for patients with advanced intraocular retinoblastoma, but systemic topotecan lactone exposure induced by both approaches may cause toxicity. The purpose of this study was to develop a topotecan-loaded ocular delivery system to minimize systemic exposure and achieve selective transscleral penetration. Methods. Biocompatible polymer implants containing low (0.3 mg) or high (2.3 mg) topotecan load were manufactured and characterized in vitro. Adrenaline (500 mug) was coloaded to induce local vasoconstriction in vivo in 2 of 4 animal groups. Implants were inserted into the episclera of rabbits, and topotecan (lactone and total) concentrations in ocular tissues and plasma were determined over a period of 48 hours. Results. In vitro, implants released 30% to 50% of the loaded drug within 48 hours and 45% to 70% by day 10. In vivo, topotecan lactone was highly accumulated in locally exposed ocular tissues (ranging from 10(5) to 10(6) ng/g in sclera and choroid and 10(2) to10(3) ng/g in retina) over 48 hours with all the formulations studied. Low vitreous topotecan lactone levels (approximately 5 ng/mL) were found in animals receiving concomitant local vasoconstriction and high load implants. Topotecan lactone concentrations in plasma and in contralateral eyes were minimal or undetectable as a marker of tissue selectivity of the proposed strategy. Conclusions. These studies may contribute to improving the efficacy and safety of chemotherapy treatments for retinoblastoma and may support the role of the local vasculature and tissues promoting drug clearance and local accumulation during transscleral drug delivery.

Primary cystadenocarcinoma of the lacrimal gland.

PURPOSE: To report a patient with a cystadenocarcinoma of the lacrimal gland, a tumor not previously described in the ophthalmic literature. Salivary gland cystadenocarcinomas constitute a distinct group of epithelial malignancies characterized by an invasive, predominantly cystic pattern of growth that have an indolent behavior and a low incidence of metastases and recurrences. DESIGN: Single interventional case report. METHODS: The clinical findings, results of imaging studies, and pathologic findings are presented. RESULTS: A 67-year-old man presented with a 5-year history of ptosis in the right upper eyelid. A lacrimal fossa tumor was found. The tumor was excised with an intact capsule, and the histopathologic diagnosis was primary cystadenocarcinoma of the lacrimal gland. The patient received no other form of treatment and has been observed for 1 year without evidence of recurrence or metastatic disease. CONCLUSIONS: Until recently, primary adenocarcinomas of the lacrimal gland were not further subclassified. Current knowledge gained from salivary gland tumors indicates that primary adenocarcinoma encompasses a group of tumors with separate morphologic features and varied biologic behavior.

Intravascular papillary endothelial hyperplasia of the conjunctiva in a horse.

OBJECTIVE: Vascular tumors of the conjunctiva in the horse are rare. We present a unique case of an intravascular papillary endothelial hyperplasia of the conjunctiva. ANIMAL STUDIED: Horse. PROCEDURES: Case report. A 6-year-old-mare presented with a red mass in the conjunctiva of the left eye. After complete ophthalmologic examination the lesion was excised. The tissue was processed for light microscopy and studied histopathologically. RESULTS: Pathologic examination revealed a nonencapsulated vascular lesion composed of confluent vascular spaces filled by multiple papillary structures composed of a central collagenous core lined by hyperplastic endothelial cells. There was neither atypical endothelial cell nor mitotic activity. CONCLUSIONS: Intravascular papillary endothelial hyperplasia is a benign proliferative lesion that should be differentiated from malignant vascular tumors.

Cirugía refractiva y cicatrización de la córnea / Refractive surgery and corneal cicatrization

This report makes reference to the refractive surgery and the corneal cicatrization. Previous description of the corneal structure, details the corneal cicatrizative process. Special attention was dedicated to the visual corrective effects following corneal surgery

Melanomas familiares / Familial melanomas

La detección de dos hermanas con melanoma coroideo, motivó una revisión bibliográfica de los casos de melanoma familiar. La hipótesis de trabajo fue, previa definición del perfil de la problación de melanomas familiares, determinar si el comportamiento biológico de estos difiere de los melanomas esporádicos, compartiendo características afines a las neoplasias hereditarias (tal como ocurre en los retinoblastomas). Se incluye además un análisis de factores ambientales y de los melanomas bilaterales