Losing sleep over apnoea- link Ocular Update

Pippa Wysong Some studies suggest patients with Edward M Weaver MD, associate professor in Toronto primary open angle glaucoma have increased of otolaryngology and chief of sleep surgery rates of snoring, insomnia and excessive at the University of Washington was not OBSTRUCTIVE sleep apnoea (OSA) could daytime sleepiness (symptoms typical of particularly surprised by the study's findings. now be added to the list of suspected risk OSA).Yet, another study showed the greater He was not part of the study group, but factors for glaucoma and other the number of apnoea symptoms OSA noted,“The possible effect of obstructive diseases, according to a recent review of the patients exhibited, the greater the increase in sleep apnoea on ocular disease is another topic in the Canadian Journal of intraocular pressure (IOP), visual field loss interesting relationship that deserves further (CJO). But authors of the review say more variance, and glaucomatous investigation.There is growing evidence of study is needed to determine just how much changes. However, some studies didn't find a many effects of obstructive sleep apnoea on OSA contributes to . correlation between glaucoma and OSA, so other organ systems.” There are several features of OSA that definitive conclusions can't be made at this He said that the article provides a good could potentially affect the health of the support a possible link between OSA and time.There may also be other factors summary of preliminary data that are out optic nerve, according to Sukhjeet Dhillon eye disease. Some studies, however, found involved that could determine an OSA there that begin to support a relationship MSc, from Canada's University of Waterloo the association between the two somewhat patient's risk for eye disease. between OSA and specific ocular disorders, School of Optometry and colleagues. weak highlighting a need for high quality One suspect eye disease is . It and it hypothesises the pathophysiological “Sleep disordered breathing is a common studies. is caused by raised intracranial pressure and mechanisms. disorder that has been increasingly Yet, some studies are more compelling in has suspected links to both apnoea and OSA has effects on various physiological associated with eye diseases. It may make terms of possible links and mechanisms, and hypoventilation. Here, studies suggest hypoxia mechanisms that may affect organs and the eye vulnerable due to the effect of would suggest the area is worth pursuing as and hypercapnia caused by the breathing physiologic systems.Transient changes in hypoxia or it can involve pathways that lead a research direction, Graham Trope MD, a abnormalities characteristic of OSA raise blood pressure, intermittent hypoxia, and to impaired autoregulation of optic nerve professor of ophthalmology at the University intracranial pressure by causing vasodilation sympathetic activation are only some of the perfusion,” they note. of Toronto told EuroTimes. in the cerebral arteries.The authors found possible mechanisms through which OSA OSA is fairly common and occurs in an The review included studies investigating one small study where 33 per cent of could cause damage. estimated nine per cent of women and 24 OSA and various eye problems including patients with intracranial hypertension had From an ophthalmology perspective there per cent of men between the ages of 30 and glaucoma, nonarteritic anterior ischemic OSA and that their eye symptoms improved aren't enough data to support changes in the 60 years. But researchers say estimates are , visual field defects, and after the OSA was treated. management of patients with eye disease and likely low, and that about 80 per cent to 95 papilledema. Although it has been suggested that OSA, but there are enough compelling data per cent of OSA cases remain undiagnosed. “The effects of OSA on body homeostasis intermittent apnoeic episodes lead to a to warrant further study, according to Dr OSA consists of repeated episodes of partial provide insight into how OSA can play a role deterioration of visual function and (or) Trope. However, he added if or complete obstruction of the airways in the pathogenesis of ocular dysfunction. ischemic damage to the optic nerve, one ophthalmologists have patients who are during sleep.Apnoea can lead to hypoxia, The immediate physiological effects of OSA cannot rule out the possibility that the middle-aged and overweight, and are OSA hypercapnea, blood pressure fluctuations, and involve hypoxia, hypercapnia, and inspiratory relation is mediated by additional factors, the suspects, it's worth referring them for a sleep possible changes in ocular haemodynamics, effort.These factors may directly impact the authors wrote. In other words, apnoea could assessment. the authors noted. functioning of the optic nerve or work in be one of several contributing factors to The researchers reviewed over 30 studies [email protected] concert to manifest as vascular sequelae,” vision problems in some patients, or possibly in the medical literature, some of which [email protected] the authors wrote. work in concert with other variables. Accurate diagnosis of preseptal and orbital essential

Devon Schuyler for inflammatory protopsis. If present, the ophthalmologist should send a culture to a has made it a much less frequent in Las Vegas patient should be evaluated for preseptal biology laboratory so that the infectious occurrence,” said Dr O'Brien.Treatment cellulitis; if absent, the patient should be agent can be identified and susceptibility can involves topical or systemic antibiotics, OPHTHALMOLOGISTS need to be able to evaluated for orbital cellulitis. Each of these be determined. Most cases are caused by sometimes with cefataxamine or ceftriaxone. differentiate between the various types of conditions has its own treatment plan. or Streptococcus preseptal and orbital cellulitis so that these pyogenes.Treatment involves incision and Orbital cellulitis patients can receive effective treatment. Preseptal cellulitis drainage of the preseptal suppuration, Proper diagnosis of the condition can be Orbital cellulitis refers to infection of the culture of the purulent material, and difficult, however. Preseptal cellulitis refers to infection of the soft tissue within the , posterior to the intravenous nafcillin or oral cloxacillin. “Navigating the course of the patient who soft tissue of the and the periocular . Dematoblepharitis and preseptal cellulitis, presents with of the eyelids can region anterior to the orbital septum.The “This is one of the true ophthalmic which also may be caused by Staphylococcus be quite challenging,” said Terrence O'Brien condition can lead to hyperaemia of the skin, emergencies.This is in the danger zone … aureus or , should be MD, speaking at the annual AAO meeting. Dr distension of the eyelids, and conjunctival and it can lead to significant morbidity and treated with culture of skin lesions and O'Brien is a professor of ophthalmology at ecchymosis. even mortality,” said Dr O'Brien. intravenous nafcillin or oral cloxacillin. Bascom Palmer Eye Institute in Palm Beach, Preseptal cellulitis may occur in a post- He said that orbital cellulitis requires an Non-suppurative preseptal cellulitis in Florida. He recommended that physicians traumatic, suppurative form, or in aggressive approach to diagnosis and children is most often caused by zero in on the most distinctive signs, conjunction with dermatoblepharitis.There management, with immediate orbital imaging. Haemophilus influenzae type B or generate a differential diagnosis, consider is also a non-suppurative form that occurs in Predisposing factors in orbital cellulitis . other findings, and perform laboratory children less than six years old. include the proximity of the nasal sinuses “This used to be a common presentation, studies before initiating therapy. When faced with a case of post-traumatic but now, widespread use of the Hib vaccine The first step, he said, is to check the eye suppurative preseptal cellulitis, the Continued on page 31

30 not just a paediatric problem Ocular Update

Pippa Wysong they have convergence insufficiency.These doesn't see anything wrong and so refers the It may be beyond what you're happy with, but in Toronto patients are usually treated with eye patient to an ophthalmologist.Asking the it may not be something that is affecting your exercises to promote strengthening of the right questions can reveal the patient has patient's daily life,” Dr Kraft said. STRABISMUS, often considered a paediatric up-close efficiency of focussing. But, in some simply noticed a normal phenomenon – the He likens this sort of situation to a person problem, may not be referred for treatment adults, the exercises don't work.“The reason fact that objects beyond or in front of an prescribed blood pressure medication in adults because of a common is that the examiner has forgotten to check object you focus on appear as double. because their blood pressure went up during misperception that the surgery in adults is the patient's focussing range,” Dr Kraft said. Patients with trauma to the eye are a a scary movie. It doesn't give the whole purely cosmetic. But correcting problems If the near-vision focus is not normal, the whole other story.A common problem is story. Some people simply have a small but such as double vision and misaligned eyes first treatment isn't eye exercises but rather double vision that occurs when the patient stable strabismus angle that doesn't cause can improve function, decrease disability, and reading correction. tries to look up – supraduction. Caused by problems. improve quality of life. “Sometimes by helping the reading and an orbit fracture, the eye muscle below is “The correct measurement of these Indeed, there are several eye muscle making it more efficient and clear, the bound. involves a two-step process where you bring problems that can be misinterpreted, and problem of convergence can actually take “Ophthalmologists often forget that if you the prism and cover in at the same time to end up being thought of as needing care of itself,” he said. have trauma to the socket, you can also diagnose their static binocular alignment, then treatment or a therapy that turns out to be And the reading problem doesn't always physically damage the muscle that helps you do the traditional cover test to diagnose the inappropriate, said Stephen Kraft MD, from happen in just patients who are over 40 – look down. It can be traumatised at the time total tendency they have,” he said. the University of Toronto.At the recent check younger adults with this complaint of surgery, or secondarily be affected by the annual Crawford Day conference at the too. Once patients have their new glasses, surgery to correct the fracture in the Strabismus surgery in adults Hospital for Sick Children he presented wait and see if the exercises are still needed socket,” Dr Kraft said. several examples of strabismus conditions In a separate presentation, John D Roarty, later, he advised. Problems looking down can be far more that fall into these categories. MD, from the department of ophthalmology disabling to a patient than the upwards Take, for example, a patient who cannot at Wayne State School of Medicine in Double vision issue problem since it can affect everything from abduct one eye. Detroit, Michigan, US, reminded the audience reading to being able to safely navigate “The most common thing people think Then there are issues relating to double that surgical treatment of true adult walking up or down stairs. It's a problem about is a which can be a vision.Appropriate use of tests and asking strabismus is not simply a cosmetic that needs to be kept in mind, and patients serious problem, but there are certain the right questions are the key to making procedure. It restores the eye back to its should be warned of it as a potential features that can lead to a diagnosis of correct diagnoses. normal condition, and gives patients proper problem from surgery. congenital Duane Retraction Syndrome Dr Kraft has seen patients complain of function. “Nature takes six to 12 months to heal (DRS) instead,” he said. double vision – coincidently after they Surgery can eliminate , re-establish these transient palsies. Some will get better, DRS has key features that don't appear in received new glasses with a strong binocularity, and restore a fuller peripheral some won't. Surgical intervention shouldn't sixth nerve palsy. One is retraction of the prescription. For these patients, the problem field (which can improve driving and other be done for at least six months to allow for eye into the eye socket.When the patient could be the glasses themselves. If glasses tasks). It can also improve a person's self spontaneous recovery,” he said. tries to look in the direction away from that aren't centred properly, a prism effect can be image, as well as improve function in Then there are adults who had surgical eye, the eye itself begins to retract into the produced which creates an unstable eye everyday activities and work, he said. correction for crossed eyes in infancy.These socket.This is because there is a alignment. For patients with strong “Changes an adult strabismus patient can people might go in for testing. Muscle testing misenervation – the lateral and medial prescriptions, check the centring and design experience after surgery include better reveals that the eyes have a tendency to rectus muscles get stimulated at the same of the glasses first, he said. depth perception, better field of vision, cross, and the patient might have surgery time. Some patients seeing double might have improved social acceptance, and better job recommended.Yet, many of these patients Along with this is a narrowing of the the problem in only one eye. Monocular performance,” he said. don't need surgery. fissure. diplopia can be due to any of several causes There can be a number of causes and Why? Because an overly aggressive muscle DRS is generally present at birth. So, ranging from an early , corneal scars, types of strabismus in the older adult, test will show what the eyes do at extremes, another aspect of diagnosis lies in the , , or more.With ranging from problems related to other eye but not that the patient actually has normal history. If the patient has had the problem patients who complain of double vision, ask problems (it can occur after cataract surgery, function when the eyes are allowed to work since birth or infancy, the condition hasn't whether it's in one eyes or both, and test for instance), and age-related changes in the together. changed, and there is retraction of the the eyes separately and together, he said. If eye. If patients need refractive surgery, do “If you use a cover and prism to see how eyeball, then think DRS, Dr Kraft said. the problem is in one eye, it's not a muscle that first before considering strabismus their eye turns too aggressively, you can A second problem that may present in the problem. surgery, he said. actually disrupt the and the ophthalmologist's office is a patient who has Then there are the patients who tell an [email protected] eyes can cross a certain number of degrees. trouble reading and gets because eye examiner they see double, the examiner [email protected]

Continued from page 30 Other risk factors for orbital cellulitis are organisms are Streptococcus pneumoniae, Dr O'Brien reminded ophthalmologists to , diabetes mellitus, and Staphylococcus aureus, Haemophlus influenzae, be alert to the signs of cavernous sinus and other structures, and the absence of . and non-spore forming anaerobes. thrombosis: rapid progression of orbital valves in the connecting veins.The principal As with preseptal cellulitis, signs of orbital Dr O'Brien said that orbital cellulitis with congestion; high fever, nausea and vomiting; routes of infection are either exogenous cellulitis include hyperaemia of the skin, sinusitis often requires collaboration with hypesthesia of maxillary division of the 5th (after trauma or surgery), or endogenous distension of the eyelids, and conjunctival otorhinolaryngology to obtain material for nerve; retinal venous engorgement; and the (with extension from adjacent structures). inflammation. In addition, orbital cellulitis may smear and culture, and then to initiate high- development of contralateral orbital Staphylococcus aureus is the principal cause of cause orbital pain (which Dr O'Brien called dose therapy with intravenous ceftriaxone. congestion. both post-traumatic and post-surgical orbital the “hallmark” of the condition), protopsis, He also warned ophthalmologists to be Finally, he emphasised the high prevalence cellulitis. and limitation of ocular motility. suspicious of the possibility of of infection in orbital cellulitis. Dr O'Brien used several photos to Exogenous orbital cellulitis should be if diabetes mellitus, immunosuppression, or “When you're doing a differential illustrate exogenous orbital cellulitis: one of managed by culturing the purulent material orbital apex syndrome are present. diagnosis of proptosis, infection should be a man who had suffered severe trauma from and administering intravenous nafcillin, Mucormycosis requires a mandatory biopsy considered at stages one, two, and three,” he a pool cue, one of a man whose eye had intravenous tobramycin, or both. for histopathology and culture, and high- said. been damaged by a pencil, and one of a man When sinusitis is the underlying factor in dose intravenous amphotericin B. who had developed the condition after orbital cellulitis, the most common [email protected] surgical repair of .

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