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vitreoctomia ed endoftalmiti

 
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vitto78



Registrato: 16/08/05 10:11
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MessaggioInviato: Lun 13 Nov, 2006 9:16    Oggetto: vitreoctomia ed endoftalmiti Rispondi citando

uno studio abbastanza incoraggiante sull'incidenza delle infezioni endocluari a seguito di vitreoctomia:

Endophthalmitis more likely with 25 gauge than 20 gauge vitrectomy, study finds

LAS VEGAS — Using 25-gauge vitrectomy instrumentation may increase the risk of endophthalmitis by as much as 12 times compared to 20 gauge instruments, according to a study presented here.

Derek Y. Kunimoto, MD, JD, and colleagues reviewed the occurrence of endophthalmitis in 5,498 vitrectomies performed over 2 years with 20- and 25-gauge instrumentation. He discussed the results of their study at the American Academy of Ophthalmology meeting.

The researchers found only one case of endophthalmitis among 4,268 procedures performed using 20-gauge instrumentation (0.018%), compared to seven cases among 1,158 procedures performed with 25-gauge instruments (0.23%).

"This is a striking and significant difference. It strongly suggests surgeons must make changes with the 25-gauge technique," he said.

Dr. Kunimoto theorized that these differences are due not to the technology but rather to surgical technique, which can be modified.

"I want to emphasize that 20-gauge vitrectomy can serve as a control to 25-gauge vitrectomy because the same surgeons who demonstrated an extremely low endophthalmitis rate for the 20-gauge vitrectomies are the ones performing the 25-gauge cases," he said.

The different rates of infection could be attributed to wound formation, lack of wound closure, early postoperative hypotony or fluid flow, Dr. Kunimoto said. He offered some suggestions for avoiding postoperative infections: The surgeon should displace the conjunctiva during sclerotomy, bevel the sclerotomy wound, spend a few extra moments searching for wound leaks, carefully monitor air-fluid exchange and place sutures in the sclerotomies.

"These results must be kept in perspective," Dr. Kunimoto said. "As surgeons we must all realize that 25-gauge surgery is still an evolving technique."

http://www.osnsupersite.com/view.asp?rid=19285
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vitto78



Registrato: 16/08/05 10:11
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MessaggioInviato: Lun 18 Dic, 2006 12:50    Oggetto: Rispondi citando

OSN SuperSite Top Story 9/12/2006

ESCRS Endophthalmitis Study confirms cefuroxime's role in reducing infection risk

LONDON — Final results of the ESCRS Endophthalmitis Study confirm the role of intracameral cefuroxime in preventing intraocular infection, according to Peter Barry, MD, Study Chairman and 2006 Ridley Medal Lecturer. He presented the findings here at the European Society of Cataract and Refractive Surgeons annual meeting.

"Cefuroxime injection lowers the chances of bacterial contamination by a factor of 5. This means that the risk rate is reduced to less than 5 in 10,000 cases," Dr. Barry said.

Cefuroxime seems to be particularly protective against streptococci, which cause extremely severe infections often leading to blindness. In the study, no cases of streptococcal infection were found in groups of patients who received cefuroxime, he said.

Cefuroxime is not licensed for intraocular use, Dr. Barry noted. For the study, investigators were required to obtain a special exemption certificate, which expired once patient recruitment ended. Most countries do allow physicians to use cefuroxime off-license, although physicians are responsible for the ramifications, he said.

Peter Barry "In practical terms, taking 750 mg of cefuroxime powder and diluting it by yourself to a concentration of 1 mg [per] 0.1 mL exposes you to all of the risks of kitchen pharmacy, with errors in dilution, a possible induction of toxic anterior segment syndromes and the frightening possibility of contamination, for example with Pseudomonas, against which cefuroxime is not effective," Dr. Barry said.

Because of this, Dr. Barry appealed to the pharmaceutical industry to provide ophthalmologists with single sterile unit doses of cefuroxime for use in the millions of cataract procedures performed annually worldwide.

In addition to the beneficial role of cefuroxime, the study established the crucial contribution of polymerase chain reaction in proving infection in suspected cases. It also established the incidence of endophthalmitis risk factors other than non-use of cefuroxime injection. In particular, silicone IOLs as opposed to acrylic lenses, as well as the use of clear corneal incisions rather than scleral tunnel incisions, were found to significantly increase the likelihood of experiencing such infections.

The ESCRS Endophthalmitis Study involved nearly 16,000 patients examined in 24 centers in nine European countries, making it "the largest study of an antibiotic in the history of medicine," Dr. Barry said.

Results of such a large study are highly reliable and should convince cataract surgeons to incorporate the use intracameral cefuroxime into their standard operating procedure, he noted.

http://www.osnsupersite.com/view.asp?rID=18342
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cyberfloaters



Registrato: 24/08/05 17:45
Messaggi: 665

MessaggioInviato: Mar 19 Dic, 2006 14:52    Oggetto: Rispondi citando

grande vitto come al solito preciso e pungente Laughing ammazza quanto e bello il navigatore che hai in macchina Laughing
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vitto78



Registrato: 16/08/05 10:11
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MessaggioInviato: Mar 26 Dic, 2006 15:18    Oggetto: Rispondi citando

Ricerca di fattori di virulenza in ceppi di Stafilococchi isolati dall'occhio

Università degli Studi di Sassari

Abstract
Gli stafilococchi sono microrganismi saprofiti della cute e delle membrane mucose dell'occhio. Tuttavia, questi microrganismi sono anche una delle principali cause di infezioni oculari. Essi sono, infatti, in grado di provocare infezioni delle palpebre (blefariti), della congiuntiva (congiuntiviti), della cornea (cheratiti) e delle strutture interne dell'occhio (endoftalmiti). Sebbene gli stafilococchi siano una frequente causa di infezioni oculari, i meccanismi mediante i quali essi provocano patologia nell'occhio sono ben lungi dall'essere completamente noti. L'obiettivo del programma di ricerca è quello di individuare la presenza di fattori di virulenza in ceppi di stafilococchi isolati dall'occhio. Lo studio si articolerà nelle seguenti fasi:
A) I prelievi per l'isolamento dei microrganismi saranno effettuati mediante tampone del bordo palpebrale, congiuntivale e/o corneale, raschiato corneale, paracentesi dell'umor acqueo, raccolta dell'umor vitreo durante l'intervento di vitrectomia. L'isolamento dei microrganismi sarà effettuato su terreno agar mannite.
B) Si procederà quindi all'identificazione biochimica degli stafilococchi.
C) Successivamente si procederà alla caratterizzazione melocolare dei ceppi isolati mediante ibridizzazione del DNA cromosomico. I ceppi di isolamento oculare saranno confrontati con i ceppi isolati da altri siti, al fine di evidenziare la presenza o meno di omologia.
D) Il passo successivo è quello di determinare la >>>

http://www.ricercaitaliana.it/prin/dettaglio_prin-2004063818.htm
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vitto78



Registrato: 16/08/05 10:11
Messaggi: 302

MessaggioInviato: Mer 24 Gen, 2007 13:30    Oggetto: Rispondi citando

una procedura sperimentale per abbassare i rischi di infezioni oculari a seguito di intervento di cataratta:

OSN SuperSite Top Story 1/19/2007

Steinert advises on prevention of endophthalmitis in cataract surgery

KOLOA, Hawaii — A comprehensive drug regimen and meticulous surgical steps are key to endophthalmitis prevention in cataract surgery, according to a speaker here.

Roger F. Steinert, MD, discussed endophthalmitis prevention at the Hawaiian Eye 2007 meeting.
Roger F. Steinert, MD, presented his preoperative, intraoperative and postoperative steps for infection prevention here at the Hawaiian Eye 2007 meeting.
Preoperatively, Dr. Steinert said he first treats chronic meibomian gland disease in blepharitis. He also tells his patients to stop wearing any and all cosmetics.
"We used to use antibiotic skin cleanser," he said, but that has fallen out of practice. "Perhaps it is time to revisit that."
Dr. Steinert also prescribes currently available fluoroquinolones, either Zymar (gatifloxacin 0.3%, Allergan) or Vigamox (moxifloxacin 0.5%, Alcon) four times a day, 1 to 3 days preop.
On the day of surgery, Dr. Steinert gives his patients antibiotic drops immediately upon their arrival in the preoperative area.
"You need to give antibiotic drops at least 30 minutes prior to surgery," he said.
In the operating room prior to surgery, Dr. Steinert said he makes sure that his assistants use proper technique preparing the skin and eyelashes, which is to stroke from the center to the periphery without return.
"Five percent betadine is a good thing applied to the globe but do not use lidocaine jelly before the betadine," he said.
Next cover and isolate the lashes and meibomian glands with an incision drape.
Prior to the incision, copiously irrigate the surgical field.
Dr. Steinert said there is still debate over clear corneal incisions.
"The only thing we can say with certainty is that not all incisions are created equally," he said.
There are also a number of issues with intraoperative antibiotics, including the debate over the ESCRS cefuroxime study. He noted that there will be a special session about the study at this year's ASCRS meeting.
After the incision closure, Dr. Steinert recommends meticulous testing for a watertight seal using fluorescein and observation of both the main incision and the paracentesis.
"When in doubt, suture," he said.
Postoperatively, Dr. Steinert starts his patients on a fluoroquinolones as soon as possible on the day of surgery.
He said there is no evidence regarding dosing frequency and duration, but fluoroquinolones are commonly prescribed four times daily for 5 to 7 days.
"The only strong evidence is for topical betadine antisepsis at the time of surgery," Dr. Steinert added.
"Draping to isolate the lashes and meibomian glands follows sound surgical principles," he said.

http://www.osnsupersite.com/view.asp?rID=20155
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vitto78



Registrato: 16/08/05 10:11
Messaggi: 302

MessaggioInviato: Ven 08 Feb, 2008 10:11    Oggetto: Rispondi citando

sperimentazione di un microchip per rilevare con tempismo l'eventuale insorgenza di endoftalmiti:

OSN SuperSite Top Story 2/6/2008

New macrochip offers potential for simplifying ocular infection diagnoses

BANGALORE, India — The introduction of a new macrochip that can distinguish between infecting organisms and make a diagnosis using multiple polymerase chain reactions promises faster, more accurate and less expensive diagnoses of ocular infections, a presenter said here.
"What we are talking about today is about critical infections such as eye infections, brain infections and septicemia where death and debility is a prospect," B.V. Ravi Kumar, MBBS, PhD, said at the All India Ophthalmological Society conference. "This is where monocular diagnostics have a great place in a country where cost-effectiveness of diagnosis is very important."
Dr. Kumar, who is the founder of XCyton, the company that manufactures the XCyto-Screen DNA Macro Chip, presented the chip as a good solution for both fast and economical diagnoses of infectious diseases.
This new technology uses multiple polymerase chain reaction (PCR) strands in one chip to ease diagnosis and reduce cost and labor, as well as the risk of cross contamination, he explained. A single tube of fluid is administered onto the chip and the particular disease that is present in the fluid is identified as an amplified dot, Dr. Kumar showed.
Dr. Kumar explained that while cultures are the gold standard for diagnoses, virus detection by culture takes a week, and with eye diseases, there is often not enough material to make a diagnosis.
This chip, when testing for conditions such as uveitis and endophthalmitis, detected 100% of the diseases, Dr. Kumar said. He noted that its specificity is higher than traditional PCR testing and requires just 5 hours to complete.
"It's enormously sensitive," he said. "Now, specificity is much higher than regular PCR because we're binding a specific sequence."
Dr. Kumar said this technology will be expanded to test for diseases such as meningitis and human papillomavirus.

http://www.osnsupersite.com/view.asp?rID=26173
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vitto78



Registrato: 16/08/05 10:11
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MessaggioInviato: Gio 27 Nov, 2008 11:32    Oggetto: Rispondi citando

CATARACT SURGERY
OCULAR SURGERY NEWS U.S. EDITION November 25, 2008
Surgeons make their own rules for endophthalmitis prevention, treatment
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David F. Chang, MD, is chair of the American Society of Cataract and Refractive Surgery Cataract Clinical Committee
David F. Chang, MD, is chair of the American Society of Cataract and Refractive Surgery Cataract Clinical Committee.
Source: Chang DF

For all the debates, panel discussions and published studies surrounding endophthalmitis infections, little is being done in the United States to uniformly track infection rates or develop specifically indicated medications.

With the growing elderly population, the number of cataract surgeries performed yearly is expected to increase, and with it, the number of endophthalmitis cases will likely rise. Many ophthalmologists are waiting for answers regarding growing antibiotic resistance, the safety of intracameral prophylactic injections and the best standard of care for treating endophthalmitis. Meanwhile, individual clinicians proceed with the surgical techniques, prophylactic measures and treatment options that have worked for them in the past.

Although no national tracking system follows endophthalmitis, the overall rate of infection appears low, according to published studies and anecdotal information. But any clinician who has had even one patient develop endophthalmitis can speak to the devastating visual consequences.

Story continues below↓
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Endophthalmitis rates after cataract surgery

In a study published in the April 2007 issue of Ophthalmology, Moshirfar and colleagues reported a rate of endophthalmitis after cataract surgery of 0.07%. The study looked at 20,013 patients who underwent surgery at one of nine centers and had received topical fluoroquinolones preoperatively and postoperatively.
Theodore Eickhoff, MD
Theodore Eickhoff

In 2007, the American Society of Cataract and Refractive Surgery Cataract Clinical Committee conducted an online survey of ASCRS members; the results were published by the committee and its chair, David F. Chang, MD, in the October 2007 issue of the Journal of Cataract and Refractive Surgery. According to Dr. Chang, a total of 1,312 members responded, of which 90% reported an infection rate of one or less than one case per every 1,000 cataract surgeries.
Francis S. Mah, MD
Francis S. Mah

Francis S. Mah, MD, put these numbers into perspective. “An extremely low rate of surgical site infections outside of ophthalmology is 1% or 2%,” he said. “We’re significantly lower than the 1% to 2% that is really good in general surgery.”

Theodore Eickhoff, MD, an infectious disease expert, agreed. “In experienced hands, bacterial endophthalmitis following ophthalmologic surgery is usually down under a tenth of a percent so you’re looking at something less than one in 1,000, and that’s pretty good,” he said.
The biggest concern

Endophthalmitis infections can develop after any intraocular procedure, including glaucoma surgery and intravitreal injections. As the number of intravitreal injections being performed has increased since anti-VEGFs became available, many calls for increased prophylactic vigilance have gone out.

At the 2007 American Society of Retina Specialists meeting, Andrew A. Moshfeghi, MD, reported a low rate of endophthalmitis after intravitreal injections among Bascom Palmer clinicians. As of April 1, 2008, approximately 25,000 injections performed since Jan. 1, 2005, had resulted in five culture-proven cases of endophthalmitis, or a rate of 0.02%.

The rate presented by Dr. Moshfeghi is similar to that published by Pilli and colleagues in the May issue of American Journal of Ophthalmology. Among 10,254 anti-VEGF infections performed over about a 2-year period, three cases of suspected endophthalmitis developed, all of which were culture-negative.

“We believe inoculation occurs at the time of the injection, so optimizing the injection protocol is important to minimize the risk of infection,” Dr. Moshfeghi said.

“With retina specialists who are very comfortable with this approach and are very cognizant of the risk performing these injections, I feel like, if anything, the rate will either stabilize or lower,” he said.

Therefore, anterior segment surgeons who perform cataract procedures may have the most reason to be concerned about endophthalmitis.

“There were 3 million cataracts done in the U.S. last year; it’s the most common surgery in the U.S. period, and as a result of that, even if you have an incidence that’s very low, much less than 1%, it still equates to many, many patients every year having a very devastating problem,” Uday Devgan, MD, FACS, said.
Outcomes

The severity of vision loss that endophthalmitis can cause is a major concern.

“Those rare patients that do get into trouble really don’t do well at all, and that’s why you hear about it because they can be devastating and often are devastating infections,” Dr. Eickhoff said.

“It’s one of the most severe complications we have of cataract surgery,” Dr. Devgan said, noting that as long as the infection goes unchecked, ocular structures can incur massive damage.

The effects can range from mild to total vision loss.

“It’s real and everybody’s scared of it because it is so terribly destructive,” Dr. Eickhoff said. “With a nasty bacterium like Staph aureus or Pseudomonas aeruginosa, it is, I think, unusual to have useful vision after, even if it’s cured.”
A range of surgical techniques

Still, no major action against endophthalmitis is currently under way. Endophthalmitis rates are difficult to quantify due to the wide variety of surgical techniques, prophylactic measures and treatments used. Most published rates today reflect the experience of a single ophthalmic surgery center or hospital, which can ensure procedural uniformity to avoid confounding variables.
Samuel Masket, MD
Samuel Masket

“You talk to 10 different surgeons, and they’re all doing something a little bit different,” Dr. Mah said.

“Most of us are going to go based on our own personal experience,” Kerry D. Solomon, MD, said.

Regarding surgical preparation, Samuel Masket, MD, said that endophthalmitis prevention depends on reducing the number of microbes on the ocular surface and the opportunity those microbes have to enter the eye. Most ophthalmologists advocate adequate eyelash and eyelid draping and the use of povidone iodine prep.
Clear corneal vs. scleral tunnel

More controversial is the surgical technique employed.

In 2007, the European Society of Cataract and Refractive Surgeons Endophthalmitis Study Group reported the results of its multinational investigation into risk factors and prophylactic measures for post-cataract surgery endophthalmitis. The prospective study, published in the June 2007 issue of the Journal of Cataract and Refractive Surgery, included 16,603 patients from 24 centers in Austria, Belgium, Germany, Italy, Poland, Portugal, Spain, Turkey and the United Kingdom.

A total of 29 patients developed endophthalmitis; 20 cases were culture-proven. The investigators reported that patients who underwent cataract surgery with a clear corneal incision had a 5.88 times greater risk of developing endophthalmitis than patients who received a scleral tunnel incision.

Additionally, in a literature review published in the May 2005 issue of Archives of Ophthalmology, Taban and colleagues showed that endophthalmitis rates appeared to have increased over the previous decade. They said the increase may have been due to the use of clear corneal incisions, which were associated with a 0.189% rate of infection, compared with 0.074% for scleral incision surgery and 0.062% for limbal incision surgery.

“There’s a learning curve in how to make a well-sealing clear corneal incision,” Dr. Devgan said. “I think as we’ve gotten better at making our clear corneal incisions, we’ve become more vigilant about things.”

“What’s probably caused the differences between the rates of endophthalmitis between clear cornea and scleral tunnel is the fact that clear cornea incisions are not as forgiving,” Dr. Mah said.

Dr. Devgan recommended using a sterile fluorescein strip to test the integrity of incisions, while Dr. Solomon noted that smaller incisions can be more effective at reducing the gap of opportunity for microbes to enter the eye.
Tracking system

Without a more concrete standard of care for preparation and surgical measures, endophthalmitis rates remain unknown. Implementing a national tracking system does not appear to be on the radar of any of the major groups in ophthalmology.

Dr. Mah said that his group, the Charles T. Campbell Ophthalmic Microbiology Laboratory in Pittsburgh, approached the National Eye Institute about 5 years ago with the idea of establishing a systematic, nationwide ocular infection tracking system, which would start with endophthalmitis.

“Eye infections really are kind of like the stepchild in the [Centers for Disease Control and Prevention],” he said. “If you look at the CDC, they’ve got various specialties, but they really don’t have a dedicated eye specialty epidemiologist.”

Dr. Mah, who serves as medical director of the Campbell Laboratory, proposed a tracking system to be coordinated with similar labs across the country. The NEI estimated a $5 million infrastructure cost for such a program and suggested the group approach the Department of Defense or industry for financial backing.

“So that was kind of where we were stuck,” Dr. Mah said, although he remains supportive of the idea.

“I think this is a perfect time to look into some type of consortium or some type of group to prospectively follow endophthalmitis,” he said.

As director of the ASCRS Task Force on infectious disease, Dr. Mah said that the organization has no immediate plans to address endophthalmitis tracking. Dr. Masket, chair of the cataract panel of the American Academy of Ophthalmology’s Preferred Practice Patterns Committee, said the same of that organization.

“Cataract surgery and endophthalmitis are definitely very important to ASCRS and our committee, but there are other things that need to be looked at,” Dr. Mah said.

“ASCRS definitely does want to get involved and try to look at these issues,” he said.
Research made complicated

Not only is tracking made difficult by the differences in procedures, but studying and approving medications can also be problematic.

“The variables in surgical technique are huge, and therefore, unless you had a very consistent operation, particularly incision, there are just so many confounding factors in having a good study,” Dr. Masket said.

As a result, physicians continue to use a variety of treatments because no specific medication is indicated for the prevention or treatment of endophthalmitis.

Another problem is the low rate of infection seen in most study populations. “It’s good that we have low rates, but it makes for difficult study,” Dr. Masket said.

“FDA labeling requires demonstration of efficacy through well-designed clinical trials, typically placebo-controlled,” Dr. Chang said. “Because of the low incidence of endophthalmitis, sufficiently large, placebo-controlled trials are too expensive and difficult to conduct.”

Such a study would necessitate either industry backing or the support of a large national ophthalmic organization. Industry is going to want to see profit, which is problematic when most surgeons are already using the newer-generation topical fluoroquinolones produced by the nation’s largest ophthalmic product companies: Vigamox (moxifloxacin 0.5%, Alcon), Zymar (gatifloxacin 0.3%, Allergan) and Iquix (levofloxacin 1.5%, Vistakon).

“I don’t know if the companies see an appropriate market that’s available to them,” Dr. Devgan said.
Rising resistance

“To make it even worse, when we want to look at specific antibiotics, now we’re looking at moving targets because the microbes continue to change their sensitivity to different antibacterials,” Dr. Masket said. “So if we were to study an antibiotic today, in 3 years or even less, that information could be very much obsolete.”

At the forefront of growing concerns about resistance is methicillin-resistant Staphylococcus aureus (MRSA).

“The percent of patients who end up with an endophthalmitis from MRSA is much, much higher now than it was in years past, and it looks like it’s on an upward trend,” Dr. Devgan said.

Additionally, whereas MRSA used to be considered primarily a hospital-acquired infection, more cases are showing community origins.
Investigations

Even though MRSA resistance to antibiotics appears to be increasing, most surgeons continue to use the newer-generation topical fluoroquinolones off-label for cataract surgery prophylaxis. Thus, potential studies could investigate their efficacy because they have not been proven in a prospective study.

“There are no good studies available yet that demonstrate that the use of topical antibiotics in fact reduces the rates of infection,” Dr. Masket said. “However, we know that the use of topical antibiotics do reduce the available microorganisms on the ocular surface. The reason we have chosen to use the fluoroquinolones is low toxicity profile, comfort, ease of administration and good broad-spectrum coverage.”

Other physicians advocate studying formulations for intracameral injection.

“Intracameral [injections have] some attractive potential advantages by virtue of actually directly delivering the drug into the compartment that we would like,” Terrence P. O’Brien, MD, said. Topical medications have to cross the epithelium and stroma before getting into the aqueous humor, he noted.

For some, a combination of topical and intracameral fluoroquinolones may be the answer. “I think fluoroquinolones in general are very intriguing because if we’re dosing someone pre- and postop, the idea that you can have an intracameral dose of the same medicine is helpful and appealing,” Dr. Solomon said.
The ESCRS study

The ESCRS Endophthalmitis Study Group looked at one specific option for intracameral injection: cefuroxime. The study found that patients who had not received intracameral cefuroxime as a prophylactic had a 4.92 times greater chance of developing endophthalmitis after cataract surgery.

Despite the study’s size and scale, these results have not led to widespread use of intracameral cefuroxime in the United States. The major issue is that cefuroxime is not approved or packaged for use as an intracameral medication.

Dr. Chang said that some ASCRS members who responded to the 2007 online survey expressed concern about mixing antibiotic preparations for intracameral injection. “The possible risks of administering ‘homemade’ intracameral antibiotic mixtures were a significant concern to 45% of surgeons not currently using them,” Dr. Chang said.

“Many ophthalmologists are reluctant to ask their operating room nurses to mix solutions for direct intracameral injection,” Dr. Masket said. “There’s a legitimate concern that a dilutional error will either cause significant toxicity and damage to the eye or might expose the patient to [toxic anterior segment syndrome].”

“I think that trial raised maybe more questions than it answered,” Dr. O’Brien said. He noted that the rate of endophthalmitis among controls in the ESCRS study population was three to four times higher than the rates typically quoted in the United States and that certain variables, including incision type and additional pharmaceuticals used, were not controlled. Additionally, the study was halted at about half enrollment because the investigators felt their goals had been met.
Intracameral use in the U.S.

Still, the ASCRS survey showed that members are not completely opposed to the idea of using intracameral injections. “Eighty-two percent of respondents overall said that they would likely inject an intracameral antibiotic if it were commercially available at a reasonable cost,” Dr. Chang said.

“It certainly makes sense to place an antibiotic directly into the surgical site of potential infection, namely the anterior chamber at the conclusion of cataract surgery,” he said.

The question then becomes, which formulation would be best for intracameral injections?

Cefuroxime is a generic drug, which translates into low financial value for any potential industry backer.

Additionally, in a study published in the October 2007 issue of the Journal of Cataract and Refractive Surgery, Dr. O’Brien and colleagues conducted a review of available data on potential formulations for intracameral injections. Gram positive organisms carried a high rate of resistance to cefuroxime, and the drug can take 8 to 12 hours to kill bacteria.

Vancomycin is another possible candidate for intracameral use. It continues to show good activity against MRSA isolates, but again, it is a generic drug.

“There’s not much incentive for a company to get that generic and then do all the work behind it, get it FDA-approved as a label indication for intracameral use,” Dr. Devgan said.
The future

Intracameral prophylactic injections for endophthalmitis may not be approved any time in the near future.

“In my capacity of ASCRS president 2 years ago, I approached the FDA on the subject, and it was made very clear to me that unit doses for intracameral administration of antibiotics would not be approved until studies demonstrated their safety and efficacy,” Dr. Masket said.

“I would hope that we would be able to organize similar studies in this country testing intracameral agents with a design that could be accepted by the FDA so that the pharmaceutical manufacturers could provide unit doses of antibiotic to the ophthalmic surgeon,” he said.

But no plans appear to be in the works. ASCRS has no proposed studies, and Alcon officials told OSN that the company has no plans to pursue an intracameral formulation of moxifloxacin for use as a prophylactic.

Evan so, Dr. Mah believes that “eventually an intracameral antibiotic method will probably become standard.”

In the meantime, physicians will continue to use a patchwork of tried-and-true methods for prophylaxis and treatment. While some may not encounter a case of endophthalmitis, others who have seen a patient go from 20/40 vision before cataract surgery to no light perception after a post-surgical endophthalmitis infection will follow the debate with particular interest. – by Jessica Loughery

http://www.osnsupersite.com/view.aspx?rid=32989
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vitto78



Registrato: 16/08/05 10:11
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MessaggioInviato: Gio 11 Dic, 2008 22:32    Oggetto: Rispondi citando

un interessante articolo sui continui progressi nella prevenzione delle endoftalmiti:

http://www.osnsupersite.com/view.aspx?rid=33245
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