Josef Flammer | |
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Born | April 21, 1948 |
Known for | Flammer syndrome |
Scientific career | |
Institutions | Basel University Hospital |
Josef Flammer (born April 21, 1948) is a Swiss ophthalmologist and long-time director of the Eye Clinic at Basel University Hospital. Flammer is a glaucoma specialist who developed a new pathogenetic concept of glaucomatous damage according to which unstable blood supply leads to oxidative stress, which in turn plays a major role in apoptosis (cell death) of cells in the optic nerve and retina in glaucoma patients. [1]
Flammer's scientific and medical endeavors were generally interdisciplinary. His first research focus was automatic perimetry for which he established normal values; [2] he studied short term and long term fluctuations of the human visual field and described influencing factors. [3] Together with Hans Bebie he developed the so-called Bebie curve, which plays a major role in the diagnosis of visual field loss due to glaucoma, he introduced the visual field indices. Flammer was one of the first researchers to demonstrate systemic side effects of locally administered beta blockers (i.e. eye drops) in ophthalmology. Flammer and his collaborators found that intraocular pressure variation is as important for the development of glaucoma, one of the main causes of blindness worldwide, as a constantly elevated intraocular pressure, [4] long considered the main, if not the only, cause of glaucoma. In numerous research projects he demonstrated that glaucoma could be caused by a dysregulation of ocular blood flow, even at normal levels of intraocular pressure. Flammer discovered that vasospasms in the eye are a manifestation of a general vasospastic syndrome. Later, he noted that such spasms are only the tip of the iceberg and an indication of a much more generalized vascular dysregulation in the human body. [5] [6] This increases the risk of eye disease, in particular of normal tension glaucoma. [7] Flammer noted that people with a primary vascular dysregulation have other symptoms and signs; this led to the establishment of the term Flammer syndrome. Flammer also demonstrated the relationship between eye disease and heart disease. [8] [9] In numerous laboratory studies, he contributed to the understanding of the role of endothelin - which according to his studies regulates retinal venous pressure - and nitric oxide in ocular perfusion. [10] He also described the pathogenic role of ocular blood flow in retinitis pigmentosa. [11]
In addition to hundreds of original papers, Flammer is the author of several books. His book "Glaucoma", intended for the general public, has so far been published in 22 languages and went through 30 different editions; "Glaucoma" is thus considered the world's most widely used non-fiction book on this ocular disease. [12] His "Basic Sciences in Ophthalmology" has received praise for demonstrating the role of chemistry and physics in modern ophthalmological diagnostics and therapies. [13] The Basel Eye Clinic organizes each year - as initiated by Flammer - one of the most renowned conferences for ophthalmologists in Europe, the Basel Ophthalmo Meeting. [14]
Glaucoma is a group of eye diseases that result in damage to the optic nerve and cause vision loss. The most common type is open-angle glaucoma, in which the drainage angle for fluid within the eye remains open, with less common types including closed-angle glaucoma and normal-tension glaucoma. Open-angle glaucoma develops slowly over time and there is no pain. Peripheral vision may begin to decrease, followed by central vision, resulting in blindness if not treated. Closed-angle glaucoma can present gradually or suddenly. The sudden presentation may involve severe eye pain, blurred vision, mid-dilated pupil, redness of the eye, and nausea. Vision loss from glaucoma, once it has occurred, is permanent. Eyes affected by glaucoma are referred to as being glaucomatous.
Eye surgery, also known as ophthalmic or ocular surgery, is surgery performed on the eye or its adnexa, by an ophthalmologist or sometimes, an optometrist. Eye surgery is synonymous with ophthalmology. The eye is a very fragile organ, and requires extreme care before, during, and after a surgical procedure to minimize or prevent further damage. An expert eye surgeon is responsible for selecting the appropriate surgical procedure for the patient, and for taking the necessary safety precautions. Mentions of eye surgery can be found in several ancient texts dating back as early as 1800 BC, with cataract treatment starting in the fifth century BC. Today it continues to be a widely practiced type of surgery, with various techniques having been developed for treating eye problems.
Amaurosis fugax is a painless temporary loss of vision in one or both eyes.
The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye.
Intraocular pressure (IOP) is the fluid pressure inside the eye. Tonometry is the method eye care professionals use to determine this. IOP is an important aspect in the evaluation of patients at risk of glaucoma. Most tonometers are calibrated to measure pressure in millimeters of mercury (mmHg).
Hyphema is a condition that occurs when blood enters the front (anterior) chamber of the eye between the iris and the cornea. People usually first notice a loss of vision or decrease in vision. The eye may also appear to have a reddish tinge, or it may appear as a small pool of blood at the bottom of the iris or in the cornea. A traumatic hyphema is caused by a hit to the eye from a projected object or a blow to the eye. A hyphema can also occur spontaneously.
Tonometry is the procedure eye care professionals perform to determine the intraocular pressure (IOP), the fluid pressure inside the eye. It is an important test in the evaluation of patients at risk from glaucoma. Most tonometers are calibrated to measure pressure in millimeters of mercury (mmHg), with the normal eye pressure range between 10 and 21 mmHg (13–28 hPa).
Ocular hypertension is the presence of elevated fluid pressure inside the eye, usually with no optic nerve damage or visual field loss.
The retinal nerve fiber layer (RNFL) or nerve fiber layer, stratum opticum, is formed by the expansion of the fibers of the optic nerve; it is thickest near the optic disc, gradually diminishing toward the ora serrata.
Optic disc drusen (ODD) are globules of mucoproteins and mucopolysaccharides that progressively calcify in the optic disc. They are thought to be the remnants of the axonal transport system of degenerated retinal ganglion cells. ODD have also been referred to as congenitally elevated or anomalous discs, pseudopapilledema, pseudoneuritis, buried disc drusen, and disc hyaline bodies.
Blurred vision is an ocular symptom where vision becomes less precise and there is added difficulty to resolve fine details.
Intraocular hemorrhage is bleeding (hemorrhage) inside the eye. Bleeding can occur from any structures of the eye where there is a presence of vasculature or blood flow. It can bleed inside the anterior chamber, vitreous cavity, retina, choroid, suprachoroidal space, or Optic disc. Intraocular hemorrhage can be subdivided depending on the location of the bleed. It may be the result of physical trauma, an uncommon side effect due to post op ocular surgery or other diseases, injuries or disorders. Severe bleeding may cause high pressures inside the eye, leading to blindness.
Pseudoexfoliation syndrome, often abbreviated as PEX and sometimes as PES or PXS, is an aging-related systemic disease manifesting itself primarily in the eyes which is characterized by the accumulation of microscopic granular amyloid-like protein fibers. Its cause is unknown, although there is speculation that there may be a genetic basis. It is more prevalent in women than men, and in persons past the age of seventy. Its prevalence in different human populations varies; for example, it is prevalent in Scandinavia. The buildup of protein clumps can block normal drainage of the eye fluid called the aqueous humor and can cause, in turn, a buildup of pressure leading to glaucoma and loss of vision. As worldwide populations become older because of shifts in demography, PEX may become a matter of greater concern.
Canine glaucoma refers to a group of diseases in dogs that affect the optic nerve and involve a loss of retinal ganglion cells in a characteristic pattern. An intraocular pressure greater than 22 mmHg (2.9 kPa) is a significant risk factor for the development of glaucoma. Untreated glaucoma in dogs leads to permanent damage of the optic nerve and resultant visual field loss, which can progress to blindness.
The Trabectome is a surgical device that can be used for ab interno trabeculotomy, a minimally invasive glaucoma surgery for the surgical management of adult, juvenile and infantile glaucoma. The trabecular meshwork is a major site of resistance to aqueous humor outflow. As angle surgeries such as Trabectome follow the physiologic outflow pathway, the risk of complications is significantly lower than filtering surgeries. Hypotony with damage to the macula, can occur with pressures below 5 mmHg for instance after traditional trabeculectomy, because of the episcleral venous pressure limit. The Trabectome handpiece is inserted into the anterior chamber, its tip positioned into Schlemm's canal, and advanced to the left and to the right. Different from cautery, the tip generates plasma to molecularize the trabecular meshwork and remove it drag-free and with minimal thermal effect. Active irrigation of the trabectome surgery system helps to keep the anterior chamber formed during the procedure and precludes the need for ophthalmic viscoelastic devices. Viscoelastic devices tend to trap produced debris or gas bubbles and diminish visualization. The Trabectome decreases the intra-ocular pressure typically to a mid-teen range and reduces the patient's requirement to take glaucoma eye drops and glaucoma medications. The theoretically lowest pressure that can be achieved is equal to 8 mmHg in the episcleral veins. This procedure is performed through a small incision and can be done on an outpatient basis.
Flammer syndrome is a described clinical entity comprising a complex of clinical features caused mainly by dysregulation of the blood supply. It was previously known as vascular dysregulation. It can manifest in many symptoms, such as cold hands and feet, and is often associated with low blood pressure. In certain cases it is associated with or predisposes to the development of diseases such as a normal tension glaucoma. Flammer syndrome is named after the Swiss ophthalmologist Josef Flammer.
Normal tension glaucoma (NTG) is an eye disease, a neuropathy of the optic nerve, that shows all the characteristics of primary open angle glaucoma except one: the elevated intraocular pressure (IOP) - the classic hallmark of glaucoma - is missing. Normal tension glaucoma is in many cases closely associated with general issues of blood circulation and of organ perfusion like arterial hypotension, metabolic syndrome, and Flammer syndrome.
Secondary glaucoma is a collection of progressive optic nerve disorders associated with a rise in intraocular pressure (IOP) which results in the loss of vision. In clinical settings, it is defined as the occurrence of IOP above 21 mmHg requiring the prescription of IOP-managing drugs. It can be broadly divided into two subtypes: secondary open-angle glaucoma and secondary angle-closure glaucoma, depending on the closure of the angle between the cornea and the iris. Principal causes of secondary glaucoma include optic nerve trauma or damage, eye disease, surgery, neovascularization, tumours and use of steroid and sulfa drugs. Risk factors for secondary glaucoma include uveitis, cataract surgery and also intraocular tumours. Common treatments are designed according to the type and the underlying causative condition, in addition to the consequent rise in IOP. These include drug therapy, the use of miotics, surgery or laser therapy.
Alon Harris, MS, PhD, FARVO is an internationally-active clinical scientist, professor of ophthalmology, educator, inventor and researcher in the field of ocular blood flow and its relationship to diseases of the eye. Harris served as the principal or co-principal investigator on more than 60 research grants, published more than 368 peer-reviewed articles, and wrote 22 books and 69 book chapters. As of 2021, he holds two patents. Harris sits on the Board of Directors of The Glaucoma Foundation and is the Vice Chair of International Research and Academic Affairs and Director of the Ophthalmic Vascular Diagnostic and Research Program at Icahn School of Medicine at Mount Sinai.
Uveitic glaucoma is most commonly a progression stage of noninfectious anterior uveitis or iritis.