The U.S. Food and Drug Administration approved iStent for glaucoma in 2012. This stent can be used in combination with cataract surgery to decrease intraocular pressure in people who have both a cataract and mild to moderate open-angle glaucoma. iStent is a type of tiny titanium tube. Its length is 1 millimeter.
Full Answer
What is the iStent and is it FDA approved?
The iStent is the first FDA approved “trabecular microbypass device.” It will likely not be the last as there are a number of other devices in clinical trials awaiting FDA approval. These devices aim to shunt aqueous fluid directly from the anterior chamber into Schlemm’s canal. What is the iStent?
How effective is the iStent for cataract surgery?
You be the judge. In the most frequently quoted study of the iStent, 50% of those with cataract surgery alone achieved an IOP below 22mmHg without use of drops whereas 72% of those with both iStent and cataract surgery achieved this result. [7]
Are You a candidate for iStent injections for glaucoma?
Leading eye professionals across the country offer iStent inject ® W for the treatment and control of eye pressure associated with mild-to-moderate open-angle glaucoma, and are available to answer your questions. Find out if you are a candidate for iStent inject ® W by talking with an iStent inject ® W physician in your area today.
What is an iStent and how does it work?
The iStent is a 1.0mm long snorkel-like device made out of medical grade titanium. It is, in fact, the smallest medical device approved for implantation in the human body. Weighing only 0.000002 ounces and with a price tag of roughly $1,000 this makes it one of the most valuable items on Earth by weight.
Why would you need a stent in your eye?
Eye stents are used as a treatment for glaucoma and, in children, NLD (nasolacrimal duct) obstructions. Stents are very small tubes usually made of plastic, fabric, or metal, which are surgically inserted to relieve obstructions and keep a path open so blood or other fluids can pass.
Can iStent be done without cataract surgery?
The iStent device is well studied and established as a safe, effective option for patients with open-angle glaucoma, with and without concomitant cataract surgery [7,8,9].
What is iStent used for?
iStent is an elegant way to help reduce intraocular pressure for patients with open angle glaucoma. It is the world's tiniest medical device – it is 20,000 times smaller than the intraocular lens (IOL) that you will receive as part of your cataract surgery.
Why are stents used in cataract surgery?
The iStent Trabecular Micro-Bypass Stent is designed to reduce your eye pressure and you can have it done at the same time you have cataract surgery.
Are eye stents for glaucoma safe?
Yes, the stents are completely safe. They can be implanted during cataract surgery, killing two birds with one stone. According to one study, 72% of patients treated with iStent inject® implants were able to come off glaucoma medication completely after a year's time.
Do eye stents need to be replaced?
The bottom line. Stents are made to be permanent and will continue to keep your artery open once they've been placed. However, stents don't cure the underlying condition that caused the buildup in your artery (atherosclerosis). You'll still need treatment to prevent future artery narrowing.
How safe is iStent inject?
The iStent inject was safe and effective for treating multiple types of primary open-angle glaucoma individually and in conjunction with cataract surgery, according to data published in Journal of Cataract and Refractive Surgery.
Can an eye stent become blocked?
Despite its proven effectiveness and safety profile, XEN gel stents (Allergan Plc, Dublin, Ireland) can become obstructed.
Where is iStent placed?
The iStent® is inserted ab interno through a small temporal clear corneal incision, bypassing the trabecular meshwork, and placed in Schlemm's canal at the lower nasal quadrant.
What are the disadvantages of stents?
damage to the artery where the sheath was inserted. allergic reaction to the contrast agent used during the procedure. damage to an artery in the heart. excessive bleeding requiring a blood transfusion.
Can you feel a stent in your eye?
The iStent procedure adds about 15 extra minutes to the surgery. What will I feel during the surgery? You may see bright lights during the surgery, but should not feel pain. You may be asked to move your eyes in different direction for placing the stents in the eye.
How long does eye shunt last?
The Ahmed Baerveldt Comparison (ABC) study demonstrated that both types of tube shunts had similar surgical success at 5 years. The Baerveldt resulted in greater eye pressure lowering but there were more early and serious complications associated with the Baerveldt as compared to the Ahmed valve.
What is a micro-bypass stent?
The iStent ® Trabecular Micro-Bypass Stent (Models GTS100R and GTS100L) is indicated for use in conjunction with cataract surgery for the reduction of intraocular pressure (IOP) in adult patients with mild to moderate open-angle glaucoma currently treated with ocular hypotensive medication.
Is iStent contraindicated for glaucoma?
The iStent ® is contraindicated in eyes with primary or secondary angle closure glaucoma, including neovascular glaucoma, as well as in patients with retrobulbar tumor, thyroid eye disease, Sturge-Weber Syndrome or any other type of condition that may cause elevated episcleral venous pressure.
What is the iStent?
The iStent is a 1.0mm long snorkel-like device made out of medical grade titanium. It is, in fact, the smallest medical device approved for implantation in the human body. Weighing only 0.000002 ounces and with a price tag of roughly $1,000 this makes it one of the most valuable items on Earth by weight.
How Well Does the iStent Work?
The answer to this question is not as straightforward as one might desire. Why? Well, the larger studies of the iStent did not look at only placement of the iStent. For every iStent placed, cataract surgery was also done on that eye. Essentially the comparison studied was iStent plus cataract surgery versus cataract surgery alone.
Can More than One iStent be Placed in My Eye?
Placement of one iStent at the time of cataract surgery may not produce much of a “wow” in terms of IOP lowering. Indeed, quite a few eye surgeons have wondered, “ Where’s the beef? ” If the iStent were a burger, you’d probably want to order a double or triple as more iStents appear to result in greater IOP lowering.
Risks of iStent Micro-Bypass surgery
Given that a single iStent only lowers the IOP about as much as a single glaucoma eye drop is it worth taking the risk of surgery for such a mild benefit?
What is an iStent?
iStent is implanted during your cataract surgery procedure. Once implanted, iStent will begin working to safely and effectively manage pressure. What’s more, patients who receive iStent may experience a reduction in glaucoma medications; but this will be at the discretion of your physician.
How does an iStent work?
iStent works like the stents used to prevent heart attacks and strokes. When blood vessels get clogged, iStent creates access to vessel flow. While a highly innovative technology, how iStent works is elegantly simple: 1 If you have glaucoma, over time the eye’s natural drainage system becomes clogged 2 iStent creates a permanent opening through the blockage to improve the eye’s natural outflow 3 Restoring this mechanism lowers and controls pressure within the eye
How small is an iStent?
The world’s tiniest medical device—iStent—is 20,000 times smaller than the intraocular lenses (IOL) used in your cataract surgery. But the size of iStent is only part of its story. By increasing the eye’s ability to drain fluid, this technology is designed to reduce the pressure in your eye.
Is iStent contraindicated for glaucoma?
The iStent® is contraindicated in eyes with primary or secondary angle-closure glaucoma, including neovascular glaucoma, as well as in patients with retrobulbar tumor, thyroid eye disease, Sturge-Weber Syndrome, or any other type of condition that may cause elevated episcleral venous pressure.
Does iStent work for glaucoma?
The surgeon should monitor the patient postoperatively for proper maintenance of intraocular pressure. The safety and effectiveness of the iStent® has not been established as an alternative to the primary treatment of glaucoma with medicatldren, in eyes with significant prior trauma, chronic inflammation, or an abnormal anterior segment, in pseudophakic patients with glaucoma, in patients with pseudoexfoliative glaucoma, pigmentary, and uveitic glaucoma, in patients with unmedicated IOP less than 22 mmHg or greater than 36 mmHg after “washout” of medications, or in patients with prior glaucoma surgery of any type including argon laser trabeculoplasty, for implantation of more than a single stent, after complications during cataract surgery, and when implantation has been without concomitant cataract surgery with IOL implantation for visually significant cataract.
What are the most common complications of a stent?
Complications were infrequent, with the most common complications being temporary stent obstruction or malposition, which resolved with observation or secondary procedures. Future studies are needed to evaluate long-term outcomes, patient satisfaction, cost effectiveness, and expanded indications.
Can two stents be implanted with the same inserter?
Furthermore, two stents can be implanted with the same inserter. Mechanism of action.
What is an iStent inject?
Unlike the original iStent, the iStent Inject is actually two stents carefully inserted into your eye – and it can be performed as a standalone procedure or in combination with cataract surgery.
What is an iStent?
The iStent is a first-generation product that is inserted as part of cataract surgery. A majority of men and women who suffer from cataracts also suffer from glaucoma, which makes a perfect option for those already undergoing surgery. This unique product is a tiny titanium tube that is 1 millimeter in size that is surgically placed into the damaged meshwork that would otherwise allow fluid to drain.
How to reduce IOP?
1 Options for reducing IOP mainly rely on pharmacological agents, laser treatments, traditional interventions, and the introduction of microinvasive glaucoma surgery (MIGS). The last 20 years have seen significant changes in all of these strategies with the introduction of new glaucoma surgical devices. When evaluating any new glaucoma device, it is critical to examine three main aspects before incorporating it into a clinical and surgical care strategy. These are efficacy, safety, and cost-effectiveness.
Is iStent the best device?
The iStent and iStent inject remain the best-studied MIGS devices that we currently have available today. It was first to market, which gives us the longest experience of use and the most available data. It is also the most studied in terms of peer-reviewed literature among MIGS devices with more than 100 published data sets on the iStent and iStent inject. The challenge with glaucoma meta-analyses is that it is often hard to compare studies that are inherently heterogenous.
Background
Chronic hepatitis B is a clinically silent and indolent disease with a long period of latency before significant adverse outcomes, such as cirrhosis, decompensated liver disease, or hepatocellular carcinoma, become manifest.
Goals of Therapy with Treatment of Chronic HBV
When considering treatment for persons with chronic HBV, it is important to consider the following goals of therapy.
Factors Used to Determine Whether to Initiate Treatment
Because of inability to eradicate HBV and the potentially long if not indefinite duration of therapy (as in the case of oral nucleoside or nucleotide analogues), treatment is not universally indicated for everyone with chronic HBV, but rather reserved for those who are thought most likely to benefit from the standpoint of disease modification.
Hepatitis B Treatment Guidance Recommendations
Several leading organizations have addressed guidance for treatment of chronic HBV, including when to initiate treatment. [ 4, 35, 36] The following summary is intended to provide a succinct description of the indications for initiating HBV treatment in persons with chronic HBV, as outlined by the different organizational guidelines.
Special Indications for Initiating Treatment
There are a variety of special clinical situations in patients with hepatitis B where antiviral therapy may be warranted regardless of cirrhosis status, hepatic aminotransferase levels, or HBV DNA levels. [ 4] The most common of these specific circumstances are listed below.
Summary Points
The goals of HBV treatment are to prevent the development of cirrhosis, hepatocellular carcinoma, and liver-related death.
Citations
1. Likhitsup A, Lok AS. Understanding the Natural History of Hepatitis B Virus Infection and the New Definitions of Cure and the Endpoints of Clinical Trials. Clin Liver Dis. 2019;23:401-16.
