Brinzolamide is a white powder commercially formulated as a 1% ophthalmic suspension to reduce intraocular pressure (IOP). Pharmacologically, brinzolamide is a highly specific,
non-competitive, reversible, and effective inhibitor of carbonic anhydrase II (CA-II), able to suppress formation of aqueous humor in the eye and thus to decrease IOP.
Ref: http://www.ncbi.nlm.nih.gov/pubmed/19668749
Showing posts with label OPHTHALMOLOGY. Show all posts
Showing posts with label OPHTHALMOLOGY. Show all posts
20111117
VISION 2020
VISION 2020 is the global initiative for the elimination of avoidable blindness, a joint programme of the World Health Organization (WHO) and the International Agency for the Prevention of Blindness (IAPB) with an international membership of NGOs ( ORBIS), professional associations, eye care institutions and corporations.
Group A - ORBIS International
ORBIS is dedicated to the prevention of blindness ... the saving of sight ... the delivery of training ... the transfer of skills... and the creation of a world where quality eye care, education and treatment are available to every human being.ORBIS Mission Statement
ORBIS is a non-aligned, non-profit global development organization. Our mission is to preserve and restore sight by strengthening the capacity of local partners to prevent and treat blindness.
20111116
LUMINATE trial
A new agent for the treatment of noninfectious uveitis: rationale and design of three LUMINATE (Lux Uveitis Multicenter Investigation of a New Approach to Treatment) trials of steroid-sparing voclosporin .
Uveitis is an inflammatory, putative Th1-mediated autoimmune disease that affects various parts of the eye and is a leading cause of visual loss. Currently available therapies are burdened with toxicities and/or lack definitive evidence of efficacy. Voclosporin, a rationally designed novel calcineurin inhibitor, exhibits a favorable safety profile, a strong correlation between pharmacokinetic and pharmacodynamic response, and a wide therapeutic window. The LUMINATE (Lux Uveitis Multicenter Investigation of a New Approach to TrEatment) clinical development program was initiated in 2007 to assess the safety and efficacy of voclosporin for the treatment, maintenance, and control of all forms of noninfectious uveitis. If LUMINATE is successful, voclosporin will become the first Food and Drug Administration-approved corticosteroid-sparing agent for this condition.
ref: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699819/
Uveitis is an inflammatory, putative Th1-mediated autoimmune disease that affects various parts of the eye and is a leading cause of visual loss. Currently available therapies are burdened with toxicities and/or lack definitive evidence of efficacy. Voclosporin, a rationally designed novel calcineurin inhibitor, exhibits a favorable safety profile, a strong correlation between pharmacokinetic and pharmacodynamic response, and a wide therapeutic window. The LUMINATE (Lux Uveitis Multicenter Investigation of a New Approach to TrEatment) clinical development program was initiated in 2007 to assess the safety and efficacy of voclosporin for the treatment, maintenance, and control of all forms of noninfectious uveitis. If LUMINATE is successful, voclosporin will become the first Food and Drug Administration-approved corticosteroid-sparing agent for this condition.
ref: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699819/
Oguchi's disease & Mizuo phenomenon
Oguchi's disease, first described by Chuta Oguchi in 1907. is a rare autosomal recessive trait characterized by congenital stationary night blindness and an unique morphological and functional abnormality of the retina. Patients have nonprogressive night blindness since young childhood with normal day vision, but they often claim improvement of light sensitivities when they remain long in the dark environment; dark-adaptation study demonstrates that highly elevated rod thresholds decrease several hours later and eventually result in a recovery to the normal or nearly normal level. The eyegrounds have an appearance of diffuse or patchy, silver-gray or golden-yellow metallic sheen and the retinal vessels stand out in relief against the radiant background. A prolonged dark adaptation of three hours ormore, leads to disappearance of the unusual discoloration the normal reddish appearance, called Mizuo-Nakamura phenomenon.
Oguchi's disease is also unique in the electroretinographic responses in the light- and dark-adapted condition. Recent identification of the arrestin gene mutation in patients with Oguchi's disease may account for the characteristic fundus and
functional abnormality.
The fundus oculi presents a most peculiar appearance. The posterior pole and in many cases the whole of fundus, instead of having a normal orange-red colour, presents a curious shining greyish-pink background, on which the retinal vessels stand out sharply. The vessels appear dark with little distinction between the arteries and the veins. The finer divisions of the blood vessels can be easily followed to their finest ramifications. At places a dark shadow or a bright white line may be seen alongside the blood vessel.
The most interesting feature of this disease in well marked cases is the reversal of all the features described above, if the patient sits in the dark for about one hour. This is called Mizuo's phenomenon. The retina looks normal and the night-blindness disappears. After the fundus has resumed the normal colour, exposure to room light of 40-50 foot candles soon leads to the appearance of fundus discolouration. It begins with a spotty distribution after about 15 minutes' exposure and within one hour the colour transformation is complete.
In some cases the discolouration of the fundus is mild and Mizuo's phenomenon is slight or absent, but night-blindness is definitely complained of.
Microscopical examination :Two peculiar features have been noticed
1. The cones are unusually numerous and are present to the practical exclusion of the rods in a large area. Many of the cones are abnormally long and their nuclei are ectopic,i.e. they are outside the outer limiting membrane. The bipolar layer is thicker than normal and the ganglion cell layer is eight to ten cell deep.
2. There is an anamolous layer of tissue between the cones and the pigment epithelium. It is not a true cellular layer, but rather appears as a degenerated syncytial structure containing many pigment granules.
Oguchi's disease has been further classified into various types
Type I : Typical cases with marked fund us discolouration, Mizuo's phenomenon and recovery of dark adaptation.
Type II:
(a) slight fundus discolouration, partial Mizuo's phenomenon and without recovery of dark adaptation.
(b) slight fundus discolouration without Mizuo's phenomenon and without recovery of dark adaptation.
It is universally agreed that the condition is transmitted as an autosomal recessive without sex discrimination. Consanguinity also plays an important part.
Oguchi's disease is also unique in the electroretinographic responses in the light- and dark-adapted condition. Recent identification of the arrestin gene mutation in patients with Oguchi's disease may account for the characteristic fundus and
functional abnormality.
The fundus oculi presents a most peculiar appearance. The posterior pole and in many cases the whole of fundus, instead of having a normal orange-red colour, presents a curious shining greyish-pink background, on which the retinal vessels stand out sharply. The vessels appear dark with little distinction between the arteries and the veins. The finer divisions of the blood vessels can be easily followed to their finest ramifications. At places a dark shadow or a bright white line may be seen alongside the blood vessel.
The most interesting feature of this disease in well marked cases is the reversal of all the features described above, if the patient sits in the dark for about one hour. This is called Mizuo's phenomenon. The retina looks normal and the night-blindness disappears. After the fundus has resumed the normal colour, exposure to room light of 40-50 foot candles soon leads to the appearance of fundus discolouration. It begins with a spotty distribution after about 15 minutes' exposure and within one hour the colour transformation is complete.
In some cases the discolouration of the fundus is mild and Mizuo's phenomenon is slight or absent, but night-blindness is definitely complained of.
 |
| Mizuo–Nakamura phenomenon. (A) A golden sheen is seen in the mid-peripheral fundus of both eyes before dark adaptation. (B) The golden sheen is extinguished after 30–45 min of dark adaptation. |
1. The cones are unusually numerous and are present to the practical exclusion of the rods in a large area. Many of the cones are abnormally long and their nuclei are ectopic,i.e. they are outside the outer limiting membrane. The bipolar layer is thicker than normal and the ganglion cell layer is eight to ten cell deep.
2. There is an anamolous layer of tissue between the cones and the pigment epithelium. It is not a true cellular layer, but rather appears as a degenerated syncytial structure containing many pigment granules.
 Classification |
Oguchi's disease has been further classified into various types
Type I : Typical cases with marked fund us discolouration, Mizuo's phenomenon and recovery of dark adaptation.
Type II:
(a) slight fundus discolouration, partial Mizuo's phenomenon and without recovery of dark adaptation.
(b) slight fundus discolouration without Mizuo's phenomenon and without recovery of dark adaptation.
| Heredity |
It is universally agreed that the condition is transmitted as an autosomal recessive without sex discrimination. Consanguinity also plays an important part.
20110920
Whitnall's tubercle
A small elevation on the orbital surface of the zygomatic bone just behind and within the orbital margin, about 11 mm below the frontozygomatic suture. It serves as an attachment for the check ligament of the lateral rectus muscle, the lateral palpebral ligament, the suspensory ligament of Lockwood and the levator palpebrae superioris muscle.
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