The unusual gamma-ray burst GRB 101225A explained as a minor body falling onto a neutron star.

The tidal disruption of a solar-mass star around a supermassive black hole has been extensively studied analytically and numerically. In these events, the star develops into an elongated banana-shaped structure. After completing an eccentric orbit, the bound debris falls into the black hole, forming an accretion disk and emitting radiation. The same process may occur on planetary scales if a minor body passes too close to its star. In the Solar System, comets fall directly into our Sun or onto planets. If the star is a compact object, the minor body can become tidally disrupted. Indeed, one of the first mechanisms invoked to produce strong gamma-ray emission involved accretion of comets onto neutron stars in our Galaxy. Here we report that the peculiarities of the 'Christmas' gamma-ray burst (GRB 101225A) can be explained by a tidal disruption event of a minor body around an isolated Galactic neutron star. This would indicate either that minor bodies can be captured by compact stellar remnants more frequently than occurs in the Solar System or that minor-body formation is relatively easy around millisecond radio pulsars. A peculiar supernova associated with a gamma-ray burst provides an alternative explanation.

Cornea in acromegalic patients as a possible target of growth hormone action.

BACKGROUND: GH exerts its effects on many organs and the eye also seems to be a target site, although few authors have investigated the corneal thickness in patients with acromegaly. AIM: To perform a detailed ophthalmological evaluation in acromegalic patients, in relation to disease activity. MATERIAL AND METHODS: Twenty-eight acromegalic patients (11 males, 17 females) and 22 voluntary healthy subjects underwent complete metabolic and ophthalmological evaluation, including retinal thickness (RT), central corneal thickness (CCT), and intraocular pressure values (IOP). RESULTS: Significantly greater CCT values were found in all acromegalic patients in comparison with controls (567 vs 528.5 µm; p<0.001), without concomitant greater corrected IOP. No difference was found for RT. Analyzing these data according to disease activity, uncontrolled patients showed greater CCT values (573.5 vs 559 µm; p=0.002) and corrected IOP (17.4 vs 16 mmHg; p=0.001) than the controlled ones. CCT also correlated with basal and nadir GH after oral glucose load levels, IGF-I levels, and duration of active disease. CONCLUSIONS: Acromegaly is characterized by greater CCT values, supporting the hypothesis that GH excess may have stimulatory effects on the cornea as well as on other target organs. Higher GH levels, disease control status and duration of active disease seem to be the main causes of increased corneal thickness. We suggest a careful and detailed corneal evaluation in acromegalic patients to prevent the potential risk of increased IOP, in addition to the already-known complications.

Treatment of malignant hypertension with an angiotensin converting enzyme inhibitor.

Malignant hypertension developed in an 18-year-old man whose primary hypertension had been diagnosed by chance. Standing blood pressure was 290/170 mmHg. Tests of renal function revealed high blood urea nitrogen and creatinine levels and low levels of both effective renal plasma flow and the glomerular filtration rate. Plasma renin activity and levels of angiotensin II and aldosterone were greatly elevated. Severe concentric left ventricular hypertrophy was noted. The patient received standard antihypertensive treatment with furosemide, propranolol, nifedipine, and prazosin, but his blood pressure did not decrease and there was no improvement in the clinical or biochemical measures. The patient was then given 20 mg of enalapril daily for one year. The inhibition of angiotensin converting enzyme immediately reduced blood pressure. Angiotensin II and aldosterone levels became normal, kidney function and hemodynamics improved, and echocardiograms revealed that the left ventricular hypertrophy had regressed. The results confirm the pathogenetic role of angiotensin II in the development of the malignant phase of hypertension.

Vitelliform dystrophy and pattern dystrophy of the retinal pigment epithelium: concomitant presence in a family.

We describe three siblings presenting unusual pigmented dystrophic lesions of the fovea. The first sibling showed macroreticular dystrophy associated with butterfly shaped dystrophy in one eye and associated with vitelliform cyst in the other eye. The second showed the atrophic outcome of a vitelliform cyst with development of subretinal neovascular membrane in one eye and a radial pigmented macular dystrophy in the other eye. The third sibling had bilateral macular vitelliform lesions. This vitelliform patterned dystrophy of the retinal pigment epithelium may represent a new form that should be classified near Best's disease and the pattern dystrophies.

[Hemorrhagic complications in drusen of the optic papilla]. / Complications hémorragiques des drusen de la papille.

A case of optic disc drusen complicated by retinal hemorrhages similar to those seen in central retinal vein occlusion is presented. While haemorrhagic complications of optic disc drusen are rare, three types have been described: small disk haemorrhages, vitreous haemorrhages and deep peripapillary haemorrhages. This clinical aspect of the haemorrhagic retinopathy presented in this paper has rarely been described; the pathogenesis of this lesion can be attributed to a progressive compression by the drusen on the central vein in the optic disk, causing a venous stasis retinopathy. Since it is impossible to remove the cause of the venous compression, the prognosis of this clinical form is always poor. Finally, the author emphasizes the need to consider this rare complication of drusen of the optic disk, especially in young patients with no systemic pathology who present this ophthalmoscopic picture, in order to avoid useless, time consuming tests and ineffective therapies.

[Neovascular glaucoma caused by branch vein occlusion and deficiency of carotid-encephalic circulation: pathogenetic correlation]. / Glaucome néovasculaire secondaire à une occlusion veineuse de branche et à un déficit de la circulation carotido-encéphalique: correlations pathogéniques.

The authors present two cases of neovascular glaucoma following branch retinal vein occlusion. The first case presented bilateral ischaemic branch retinal vein occlusions. In this case there was bilateral impairment of blood flow in the carotido-cerebrovascular system, more marked on the side where the neovascular glaucoma was present. The second case developed neovascular glaucoma following an ischaemic branch retinal vein occlusion of the right eye and had bilateral carotid stenosis that was more complete on the right: where the neovascular glaucoma occurred. The authors analyse the main pathogenic hypothesis of neovascular glaucoma, and suggest that it could be the result of the concurrent action of posterior ocular alterations (like retinal ischaemia following a branch retinal vein occlusion) and of cerebrovascular insufficiency. This second factor could contribute to global ocular ischaemia, thus, involving the anterior vascular structures of the eye as well.

[Unusual associations of pattern dystrophies]. / Associations inusuelles dans les dystrophies en réseau.

Pattern dystrophies are a group of inherited abnormalities of the macular pigment epithelium. They include reticular, macroreticular and butterfly-wing dystrophies. Several cases of pattern dystrophies associated with other diseases are reported. In one patient with reticular dystrophy of the retinal pigment epithelium this was combined with congenital hereditary deafness. Both affections were probably transmitted by a single pleiotropic gene. Apart from the typical reticular pattern in the macula there were atrophic areas that could have resulted from progression of the dystrophy. The two other cases were from the same family, one member showing macroreticular dystrophy associated with vitelliform macular dystrophy, and another a butterfly-wing dystrophy. These findings confirm the observation that different pattern dystrophies can occur in the same family and prove that such lesions can be associated with vitelliform dystrophy. The hypothesis is raised that pattern dystrophies and vitelliform dystrophy, although presently described as different clinical entities, are a single disease expressed in various manners.

[Acute ischemia of the optic nerve after retrobulbar injection]. / Ischémie aiguë du nerf optique après injection rétrobulbaire.

The authors present a case of acute amaurosis following a retrobulbar injection of anaesthetic. The patient was a mononephric subject in hemodialytic treatment receiving, therefore, a daily therapy by heparin. The ophthalmoscopic feature reveals a pale optic disk oedema, normal arteries and tortuous veins; the fluorescein angiography confirms the papillary oedema and the normal arterial fillings. The echographic picture shows an hematic collection through the nerve sheath. The authors analyze the main pathogenic hypothesis of the amaurosis which should be ascribed to an acute ischemia of the disk caused by the hematoma formed through the nerve sheath. The role of the general conditions of the patient, mononephric in hemodialytic treatment, is emphasized as a possible risk factor even for a retrobulbar injection.

[Peripheral retinal telangiectasis in retinitis pigmentosa]. / Télangiectasies rétiniennes périphériques dans la rétinopathie pigmentaire.

The association between retinitis pigmentosa and retinal telangiectasis has been rarely reported. The case of a young woman affected with retinitis pigmentosa and telangiectasis involving bilaterally and symmetrically the inferior retinal periphery is described. Moreover, the patient showed a high degree edema of the retina produced by the permeabilization of the retinal capillaries (especially foveal capillaries) and by the passage of fluid from the choroid through the damaged retinal pigment epithelium. The telangiectasis were successfully treated with cryotherapy. The telangiectasis found in patients with retinitis pigmentosa have to be distinguished from other forms of telangiectasis, as those found in young males or those of the temporal retinal periphery of adults, in which respect they have particular characteristics. The cause of the telangiectasis and of the breakdown of the blood-retinal barrier in retinitis pigmentosa is not know. It is probable that they are produced by a toxic or inflammatory action on the vessels mediated by retinal antigens.

[Choroidal metastasis of a testicular embryonal carcinoma]. / Métastase choroïdienne d'un carcinome embryonnaire du testicule.

A rare case of choroidal metastasis of testicular embryonic carcinoma origin is described, and pathologic features illustrated. The differential diagnosis of primary and metastatic ocular tumors is discussed. Because of the possibility of a primary ocular origin of this tumor and its rapid clinical evolution, the need to perform a systematic search for a primary testicular carcinoma in young male patients is emphasized.

[Diabetic papillopathy and pregnancy. Clinical contribution and pathogenetic considerations]. / Papillopathie diabétique et grossesse. Contribution clinique et considérations pathogéniques.

Bilateral mild diabetic retinopathy and disc swelling occurred in a young woman with type I diabetes during the second month of pregnancy. The disc edema showed the typical pattern of diabetic papillopathy (D.P.). This is a recently discovered syndrome of juvenile diabetics characterized by transient bilateral edema of the optic disc with minimal functional impairment. The features of D.P. and two different pathogenetical hypotheses, ischemic and dysmetabolic, expressed by other authors, are listed in detail. The case described showed a particular evolution, with bilateral prepapillary transitory neovascularization followed by scant glial reaction. Moreover pattern VEPs analysis showed a clearly increased latency. These findings suggest that both dysmetabolic (VEPs increased latency) and and ischemic (neovascularization) stimuli are responsible for D.P., even if differences with typical ischemic optic neuropathy are evident.

Deep levator palpebrae superioris detachment during aponeurosis surgery via transcutaneous approach in ptosis correction.

PURPOSE: To evaluate the efficacy of deep levator palpebrae superioris - Müller's muscle complex detachment from conjunctiva and other connective tissues in order to improve post operative lid opening and levator function for ptosis surgery via the transcutaneous approach. METHODS: In this retrospective study, 23 patients (29 eyelids) were surgically treated for ptosis repair between 2003 and 2008. All surgery was performed by the same surgeon. Patients were divided into 2 groups. The first group (12 patients) consisted of patients who underwent deep levator dissection during surgery; the second group (11 patients), used as control group, consisted of patients treated without deep levator dissection. Postoperative lid opening was compared in the two groups using the Mann-Whitney non-parametric test. RESULTS: The comparison between change in lid opening changes between the two groups was statistically significant (P<0.01). CONCLUSIONS: Deep levator detachment can be included among standard surgical steps during ptosis surgery via transcutaneous approach in order to improve postoperative lid opening and levator function.

[Adenocarcinoma of the lacrimal gland in bilateral retinoblastoma treated with external radiotherapy: a case report]. / Adénocarcinome de la glande lacrymale dans un rétinoblastome bilatéral traité avec radiothérapie externe : à propos d'un cas.

This clinical case report describes the clinical findings and diagnosis of lacrimal gland adenocarcinoma that developed 20 years after external beam radiotherapy in the treatment of bilateral retinoblastoma. Visual acuity, slit lamp biomicroscopy, fundus color photography, nuclear magnetic resonance, lateral orbitotomy and histological analysis are described.

Retinal myelinated nerve fibers associated with macular pseudohole.

We report the case of a 24-year-old woman who presented unilateral extensive peripapillary myelinated nerve fibers associated with macular pseudohole and bilateral low myopia. Visual acuity, slit lamp biomicroscopy, automated perimetry, fundus color photography, and optical coherence tomography (Stratus OCT) were performed. We discuss the clinical findings and diagnostic details of unilateral extensive peripapillary myelinated nerve fibers associated with macular pseudohole.

Tonometers and infectious risk: myth or reality? Efficacy of different disinfection regimens on tonometer tips.

PURPOSE: To evaluate the adequacy of common disinfection regimens for disposable tonometer tips and assess if disinfection of reusable prisms or the use of disposable tips is preferable. METHODS: We used disposable tonometer tips, using the same material and tip diameter of standard Goldmann tonometer prism. Strains of Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilisand Candida albicanswere tested according to the European standard guidelines for disinfectants test. Antimicrobial effectiveness of the following disinfection practices has been assessed: dry wipe, Minuten wipes (Alpro), soaking in 3% hydrogen peroxide, 0.5% benzalkonium chloride, and 0.5% Pantasept for 1, 5, and 15 min. All tests have been performed three times and all conditions tested in duplicate. RESULTS: Dry wiping and 1 min soak in 3% hydrogen peroxide were ineffective on all microrganisms. Minuten wipes, 1 min soak in 0.5% benzalkonium chloride or 3% hydrogen peroxide were ineffective on B. subtilis. 0.5% Pantasept soak was effective in 1 min for all microrganisms tested, whereas 3% hydrogen peroxide and 0.5% benzalkonium chloride soaks were effective when performed for at least 5 min. B. subtiliswas the most resistant organism to disinfectant regimes at 1 min time. CONCLUSIONS: Results of our study demonstrate a relative disinfection efficacy for the different evaluated regimens, provided that correct exposure times are adopted for the chosen disinfectants, a condition difficult to ensure in a busy clinic setting. We conclude that disposable prism tonometry provides a safe alternative to Goldmann tonometry.

VECPs and optic disc damage in diabetes.

Abnormal VECP latencies can be found in type 1 diabetic patients without retinopathy or neuropathy. The pathogenesis of this finding is still unclear. The authors report the clinical history of a diabetic patient showing normal fundus, normal oscillatory potentials, and pathological VECP latency on first examination. The clinical follow-up of this patient showed rapid evolution toward proliferative retinopathy. This finding is suggestive of a peripheral (optic nerve or retina) origin of the VECP impairment.

Incomplete Wolfram syndrome: clinical and electrophysiologic study of two familial cases.

Wolfram, or DIDMOAD, syndrome is a genetic disorder characterized by diabetes insipidus, diabetes mellitus, optic atrophy and deafness. We studied a family in which only diabetes mellitus and primary optic atrophy were present in three female siblings. Two of these patients, fraternal twins, were subjected to a complete electrophysiologic examination. The possibility of an incomplete clinical expression of Wolfram syndrome, hypotheses of its genetic transmission, and diagnostic problems are discussed.

Multifocal choroiditis: indocyanine green angiographic features.

The aim of this study is to retrospectively evaluate the indocyanine green (ICG) angiographic features in 13 patients affected by multifocal choroiditis. We identified two clinical and angiographic patterns. The 'active' pattern showed hypofluorescence up to the late phases and more extensive choroidal involvement than presumed by ophthalmoscopy and fluorescein angiography. In the 'inactive' pattern, ICG angiography showed hypofluorescence during all the phases: no increase in lesion number was observed between early and late phases. Choroidal neovascularization was present in 10 patients, and it was bilateral in 2 of these: it occurred only in the inactive stage. The appearance of choroidal lesions in IGC angiography supports the hypothesis of inflammatory involvement of the choriocapillaris as the pathophysiological mechanism of the disease.

Study of pituitary secretion in relation to retinopathy in patients with juvenile diabetes mellitus.

Fifteen juvenile diabetic patients with normal eye fundus, 6 with non proliferative retinopathy, 5 with proliferative retinopathy and 5 healthy control subjects were studied in order to investigate pituitary function in relation to diabetic retinopathy. ACTH values at 08(00) and 18(00), hPRL and TSh secretion in response to 200 microgram TRH i.v., and GH secretion in response to 500 mg oral L-dopa were evaluated. In all diabetic subjects, 08(00) ACTH levels were lower than in controls. Basal hPRL, TSH and GH values of the diabetics did not differ from those of the controls. No significant differences were found in hPRL levels in response to TRH, whereas significantly lower TSH responses were found in the diabetics. L-dopa caused a significantly different response of GH in the diabetic subjects compared to controls. There is thus a considerable derangement in pituitary hormone secretion in juvenile diabetics mellitus.