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2.
Curr Biol ; 17(24): 2122-8, 2007 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-18082405

RESUMO

As the ear has dual functions for audition and balance, the eye has a dual role in detecting light for a wide range of behavioral and physiological functions separate from sight. These responses are driven primarily by stimulation of photosensitive retinal ganglion cells (pRGCs) that are most sensitive to short-wavelength ( approximately 480 nm) blue light and remain functional in the absence of rods and cones. We examined the spectral sensitivity of non-image-forming responses in two profoundly blind subjects lacking functional rods and cones (one male, 56 yr old; one female, 87 yr old). In the male subject, we found that short-wavelength light preferentially suppressed melatonin, reset the circadian pacemaker, and directly enhanced alertness compared to 555 nm exposure, which is the peak sensitivity of the photopic visual system. In an action spectrum for pupillary constriction, the female subject exhibited a peak spectral sensitivity (lambda(max)) of 480 nm, matching that of the pRGCs but not that of the rods and cones. This subject was also able to correctly report a threshold short-wavelength stimulus ( approximately 480 nm) but not other wavelengths. Collectively these data show that pRGCs contribute to both circadian physiology and rudimentary visual awareness in humans and challenge the assumption that rod- and cone-based photoreception mediate all "visual" responses to light.


Assuntos
Conscientização/fisiologia , Ritmo Circadiano/fisiologia , Luz , Reflexo Pupilar/fisiologia , Células Ganglionares da Retina/fisiologia , Idoso de 80 Anos ou mais , Cegueira/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/anormalidades
3.
Br J Ophthalmol ; 91(6): 731-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17050577

RESUMO

PURPOSE: Clinical outcomes for phacoemulsification surgery are still compared with the almost 10-year-old benchmark of the 1997-98 National Cataract Surgery Survey (NCSS) published in this journal. Extraneous to the peer-reviewed research literature, more recent databases suggest much better results may be being obtained. This offered the rare opportunity to perform an audit as research investigating if this was indeed the case and a new benchmark is needed, with the additional standard of rigorous study peer review by independent senior ophthalmologists. At this pilot centre for Patient Choice provision, all cataract surgery was performed on Consultant-supervised training lists, a novel extension in-sourcing care using public resources rather than to an independent sector that may not be supervised by NHS Consultants. Patient satisfaction was also surveyed. We asked whether the NCSS is out-of-date, and whether good outcomes on Choice schemes are compatible with Consultant-led training within the National Health Service? METHODS: An audit of 1000 consecutive patients undergoing cataract surgery on Patient Choice at the Western Eye Hospital between October 2002 and September 2004. All subjects were scheduled for phacoemulsification. A novel policy was extending "choice" onto training list slots for this period. A validated questionnaire assessed patient satisfaction. RESULTS: A best corrected visual acuity of 6/12 or better was obtained in 93% of cases. Over 80% of cases were +/-1 D of target refraction (65.7% within 0.5 D). The total incidence of complications was 8.7%. Overall incidence of major complications was 2.4%. Incidence of vitreous loss was 1.1% and that of endophthalmitis 0.1%. Complications rates were lowest for consultants (less than 1%). User satisfaction with having cataract surgery on "patient choice" was high. CONCLUSIONS: Cataract surgery under patient choice on supervised training lists is associated with a visual outcome and an incidence of complications at least as good as the published national average. User satisfaction is high. Cataract surgery under patient choice is compatible with training activity in receiving hospitals. The improvement in outcomes since the 1997-98 NCSS suggest that the accepted standards for complication rates should be updated to reflect the fact that phacoemulsification has become an established procedure.


Assuntos
Benchmarking , Educação de Pós-Graduação em Medicina/organização & administração , Facoemulsificação/educação , Facoemulsificação/normas , Medicina Estatal/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Comportamento de Escolha , Competência Clínica , Consultores , Feminino , Humanos , Londres , Masculino , Auditoria Médica , Corpo Clínico Hospitalar , Pessoa de Meia-Idade , Participação do Paciente , Satisfação do Paciente , Facoemulsificação/efeitos adversos , Resultado do Tratamento , Acuidade Visual
4.
Orbit ; 24(2): 121-4, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16191801

RESUMO

The authors report a family with familial Bell's palsy affecting seven individuals, six of whom are females. This is a distinct subtype of Bell's palsy with a predilection for juvenile females, previously reported only very rarely. In conjunction with a review of the literature, this case suggests that this phenotype carries with it a greater risk of serious complications affecting the eyelids and lacrimal gland. These carry significant functional and cosmetic implications owing to aberrant regeneration of the seventh, sixth and possibly third cranial nerves, chronicity and relapses. Clinical features include synkinesis of the eyelids with the orbicularis oris causing synkinetic ptosis, recurrent paralytic ectropion, paralysis of facial muscles of expression with dry eye, hyperlacrimation (crocodile tears), and transient strabismus. Clinically, the decision to offer surgery in place of conservative treatment should consider the natural history of chronicity and relapses often seen with this subtype of familial Bell's palsy. Botulinum toxin injections are especially versatile in managing the complications associated with this phenotype.


Assuntos
Paralisia de Bell/genética , Oftalmopatias/genética , Adulto , Fatores Etários , Paralisia de Bell/complicações , Consanguinidade , Oftalmopatias/etiologia , Pálpebras , Feminino , Predisposição Genética para Doença , Humanos , Aparelho Lacrimal , Fenótipo , Fatores Sexuais
6.
Clin Otolaryngol Allied Sci ; 29(3): 288-9; author reply 290, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15142081

RESUMO

We describe how pupillary reactions, used as an index of optic nerve function, can be elicited using only one working pupil. This is to challenge the conclusion of a study that did not appreciate this physiological phenomenon and thus gave rise to erroneous conclusions that might otherwise limit the scope of pupil measurements during and after surgery. For suitable cases, non-opioid anaesthesia and further clinical development of pupillometry are suggested by us as measures to monitor optic nerve function.


Assuntos
Endoscopia/efeitos adversos , Traumatismos do Nervo Óptico/prevenção & controle , Nervo Óptico/fisiologia , Órbita/lesões , Reflexo Pupilar/fisiologia , Humanos , Monitorização Intraoperatória/métodos , Traumatismos do Nervo Óptico/diagnóstico , Seios Paranasais/cirurgia
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