Blog

November, 2020

Treating pressure:

Pressure can be manipulated in many different ways: medical, laser or surgical. Surgical intervention can have many guises, including minimally invasive surgery, which tends to be an excellent choice in early disease. Some patients may require filtration surgery, with the traditional technique being trabeculectomy. However, in situations where a trabeculectomy has failed or likely to fail, tube shunt should be considered.

What is a tube?

The basic design of every shunt is a silicone tube connecting the interior of the eye to a plate, secured in the space underneath the superficial skin of the eye. Hence it creates a conduit between:

  • The inside of the eye
  • The surface of the eye

The tube is initially blocked with a large suture inside the hollow lumen: without this the fluid of the eye would ‘gush’ out of the tube, causing the pressure in the eye to go dangerously low. A pressure of less than 5mmHg is called hypotony and occasionally this needs to be treated.

With time, the plate of the tube develops resistance, causing the pressure to go up. Hence around the two-month time frame, the large suture is safely removed in theatre to enable the flow of the tube to be optimal. It is always safer to do remove this ‘tube blocking stitch’ in theatre at approximately two months due to:

  • It is a sterile environment, minimising risk of infection
  • The position of the tube inside the eye can be safely visualised whilst the internal blocking stitch is removed: this will minimise the risk of the tube itself from moving (retracting)

It can be conceptualised that creating a tract from inside the eye to the surface can potentially cause an entry port for microbes within the ocular surface into the eye. This of course is critical to avoid and is done so by meticulous closure of the ‘skin of the eye’, called the conjunctiva. Hence, once the plate is firmly secured onto the surface of the eye, the following steps are taken to ensure the tube is not exposed or erodes through the surface:

  • A barrier is place over the tube
    • The most commonly used is called ‘tutoplast’
    • This is commercially prepared pericardial tissue, hence rigorous tests are applied to enable use. The only exception to this is prion’s disease, however no cases have been reported in glaucoma surgery.

Where do we put the tube?
Most commonly used are non-valved tubes, enabling fluid to flow freely from inside the eye:

  • Baerveldt tube
  • Paul tube

Furthermore, choices exist as to where to place the tube inside the eye. Key determinants that modulate the choice of implantation include:

  • Space in the eye
    • The space between the cornea and lens is called the anterior chamber
    • Variability exists as to the space in the anterior chamber
    • If there is adequate space, the tube can be implanted here
    • If this space is minimal, the cornea/iris is pathological, the view of the front of the eye is compromised, an alternative location to implant should be sought
    • Locations can include:
        • Behind the iris (the ciliary sulcus)
          • https://bmcophthalmol.biomedcentral.com/articles/10.1186/s12886-020-1329-1
        • Pars plana
          • This of course requires the vitreous humour (‘jelly’) being removed at the time of tube implantation (vitrectomy).
          • Note, the human eye does not require the vitreous humour and indeed many instances a vitrectomy is required for various pathologies
  • Co-pathology
      • In situations where there is dual pathology (for instance glaucoma and pathology in the back of the eye), it can be sensible to do combined surgery
    • This would be a consideration of a pars plana tube

Common indications for tubes

  • Failed trabeculectomy
  • Situations where a trabeculectomy is likely to fail, the so called ‘secondary glaucoma’s’ including:
    • Rubeotic glaucoma (secondary to vascular retinal disease most commonly vein occlusions and diabetic eye disease)
    • Traumatic glaucoma
    • Glaucoma in the presence of a corneal graft
    • Glaucoma secondary to retinal surgery, such as for retinal detachment repair
    • Paediatric glaucoma

Common scenarios where a tube may not be sensible

  • When general anaesthesia is not an option due to systemic co-morbidities.
  • In this situation, a different type of treatment called cyclodiode laser may be an alternative option (see http://www.ophthalmologyinpractice.co.uk/managing-rubeotic-glaucoma-at-the-western-eye-hospital)
    • Cyclodiode laser also has risks and benefits, with the decision to proceed with treatment not to be undertaken lightly.
    • Whereas tube surgery helps fluid egress out of the eye (thereby reducing the pressure), cyclodiode laser reduces the formation of fluid in the first instance (i.e. reducing the inflow of fluid)

Literature

Amongst other parameters, the AVB study looked at patients undergoing Baerveldt tube surgery. The following results in 114 patients having this type of tube were noted at baseline and at five years:

Mean pressure (mmHg)  Number of drops
Baseline 31   3.1
Five years  13.6  1.2

Post-operative issues encountered included high pressures or low pressures.

An interesting point is raised here which should be emphasised. In other types of glaucoma surgery, the aim is to be without drops (so called complete success). However, with tube surgery this is usually not possible. Drops will be required to work synergistically with the shunt to achieve the desired level of pressure. This expectation of qualified success is important to note and be aware of prior to undertaking surgery.

Gurjeet Jutley
November 2020

June, 2020

Due to the current Covid-19 pandemic, healthcare has had major reforms in how we are delivering help to our patients. The aim always has been and always will be optimal patient safety.

Systemic health

Potentially appointments may be rescheduled to help reduce the spread of the infection and protect the health of all patients, particularly the most vulnerable.

Many glaucoma patients are at higher risk of complications should they contract Covid-19, due to other underlying health conditions. Therefore, the balance of risks has to be assessed for each patient before a decision is made regarding their eye treatment.

Routine appointments

Routines appointments have been deferred for all patients. These will be rearranged as soon as it is deemed safe to do so. Where possible, virtual assessments will be utilised.

New Patients

The key is affective stratification and safe triage. Once a triage letter is seen, this will dictate whether a patient is:

  • Seen face to face
  • Virtually
  • Postponed

Surgery

Patients at high risk of losing sight and requiring surgical intervention, will be prioritised as much as possible.

What to expect if face-to-face treatment is essential

As outlined above, face-to-face treatment will only take place when there is a high risk of sight loss, or significant lifestyle impairment. When a patient has to attend an appointment the guidelines below will be followed:

  • Contact time will be reduced to an absolute minimum. As much medical and ophthalmic history will be established before the patient enters the consulting room.
  • Other than the clinical examination, the ophthalmic surgeon will keep a distance of two metres way from the patient.
  • The examination will be kept brief and concise.
  • Exacting hygiene standards will be followed throughout.
  • PPE will be worn by medical staff and removed in line with the guidelines.
  • The need for any procedures that are not absolutely essential will be minimised.

Making use of video appointments

Every effort will be made to keep immunosuppressed, vulnerable and high-risk patients away from face-to-face appointments that increase the risk of infection. Wherever possible video consultations will be offered. They are also likely to be offered for new patients with a potentially serious condition and for assessing outpatient emergencies.

This blog is contributed by Gurjeet Jutley.

Guidelines issued by our Royal College of Ophthalmologists to to help practice under such difficult circumstances
May, 2020

As a result of the current restrictions due to the global Covid-19 pandemic many medical procedures have been postponed indefinitely. This is to minimise infection rates and increase capacity for critical conditions.

Covid-19 precautions

People with glaucoma should adhere to the general guidelines:

  • Maintain social distancing
  • Wash your hands regularly
  • Wear a mask when being around other people
  • Ventilate rooms
  • Avoid gatherings

Outpatient care
If you are currently receiving outpatient care for glaucoma, the medical team will assess your need for urgent treatment. You are only likely to receive treatment if you’re deemed to be at very high risk of sight loss in the next few months. If your treatment is not regarded as urgent, any existing appointments you have will be deferred.

You should continue with your current treatment regime. If you notice any sudden change in your vision, please seek help immediately.

New patients
Unless you have urgent need for treatment due to a serious or worsening condition, any scheduled new patient appointment will be deferred. This is to ensure that all urgent cases can be treated quickly.

If you’re experiencing sudden loss of vision, pain or other concerning symptoms, it’s important to have an assessment. Your ophthalmologist will be able to advise by telephone and schedule a face-to-face appointment if necessary.

If you are awaiting surgery
Most glaucoma surgery is being deferred with safety paramount in mind. This doesn’t mean you treatment is being cancelled, it’s merely being delayed.

If you are at high risk of sight loss over the next few months or significant impairment of your daily life, then it’s likely your surgery will be deemed as urgent.

Whatever your situation it’s important to liaise with the team for advice about treatment and rescheduling.

Managing your glaucoma treatment at home

  • You should continue managing your glaucoma at home as prescribed by your ophthalmologist.
  • If you use eye drops to help manage your symptoms, it’s recommended that you regularly wash your hands to help reduce the risk of infection.

If you develop any of the following symptoms you should seek help immediately;

  • Eye pain, vomiting or nausea
  • Partial loss of vision
  • Flashes or floaters in your eyes
  • A sudden change to your vision, such as blind spots or blurriness.

This blog is contributed by Gurjeet Jutley.

April, 2020

Glaucoma Management Plans during COVID 19

Our Royal College has issued guidelines for the management of glaucoma during the COVID 19 outbreak. The idea is to strike a pragmatic balance – looking to maintain care where it is essential and to defer care for patients who can safely wait.

Assessing risk

Many glaucoma patients fall into the most at-risk categories for acquiring COVID-19, including age and existing co-morbidities. Hence, the priority will be patients lives in the first instance. When making decisions about how to manage glaucoma patients, we assess the risk of imminent visual loss in the patient, the risk of COVID-19 spread by attending hospital and the potential loss of life of glaucoma patients if they contract COVID-19.

Prioritising surgery

Clinical details of each patient will be stratified to identify who needs immediate surgery and whose treatment can be deferred. In short, glaucoma surgery requires careful attention to detail, lots of follow-up and tweaking, whether it be from laser, injections, taking out stitches, etc. Hence undertaking surgery is not an easy decision in this environment. Factors that will be considered includes:

  • The level of vision
  • Extent of visual field loss in the affected eye
  • Whether it’s an only seeing eye
  • The rate of visual deterioration
  • The level of intraocular pressure.

Treating new patients

Doctors are reviewing all referrals and making difficult decisions based on the referral letter. The initial information from the referral source and medical history via community care is used to stratify the likelihood of glaucoma and the extent of the disease. If deemed high risk and no contra-indications, empirical treatment with a topical prostaglandin via a prescription through the GP is being commenced. The follow-up face to face assessment is subsequently scheduled for some months later.

Where possible, it is important to explain to the patient the nature of their condition, how to apply drops, receiving repeat prescriptions and assess side effects via a video or telephone consultation. The patient should be advised that the treatment is a protective measure and may change after a formal assessment.

Similarly, patients with advanced glaucoma can receive a remote consultation and be offered primary intervention, often medically.

Outpatient follow-up reviews

Doctors are working through lists of thousands of patients to stratify patients into low, medium and high-risk categories based on their disease severity and underlying pathology. Low risk patients will be written to in order to inform them of the delay in their appointments and give them details of what to do if they feel their condition has deteriorated.

Medication changes can be arranged remotely or face-to-face if there are serious concerns a condition may be worsening. Note: high risk patients may be offered face-to-face depending on the severity of the conditions. As with all face-to-face consultations at this time, the RCOphth guidance on minimising risk will be followed.

This blog is contributed by Gurjeet Jutley.

April, 2020

Coronavirus Update

The outbreak of this pandemic has sadly led to restrictions being placed across wide facets of everyday life. The Royal College of Ophthalmologists have acted to give guidance to help clinical practice under such difficult circumstances.

Balancing risk

The aim of clinicians currently is to balance the risk of possibly acquiring COVID-19 infection in the eye clinic versus the risk of harm as a result of failure to treat a serious eye problem. The College is therefore advising all NHS Clinics, private practice and independent treatment centres to postpone all routine ophthalmic surgery. All face to face outpatient appointments have been ceased, with caveats existing related to urgent risk of sight loss and harm.

The role of managers and administrators

Managers and administrators are working extremely hard to ensure the guidelines are followed wherever possible. All routine procedures will be cancelled and rebooked, deflecting any non-serious unplanned attendances and ensuring that staff are able to identify and isolate high-risk patients. The current challenge throughout the world is to ensure that there’s an adequate supply of PPE: it is imperative that this target is met as the long term consequences are grave. Managers are also ensuring that latest government information regarding COVID-19 is disseminated among staff.

The role of ophthalmology consultants

Protocols have been drawn out to:

  • Identify those patients to defer and by what time-frame
  • Those to discuss over the phone
  • Those to give empirical treatment to

We are working with non-medical and admin staff to continually communicate with patients as to whether they still need to attend hospital with preserved safety versus remote monitoring.

Staff and patient protection

As ophthalmologists and other clinical professionals are in prolonged close contact with patients, a scrupulous standard of infection control is being developed. This includes risk stratification, isolated area for treating confirmed COVID-19 patients, regular cleaning and prioritising getting PPE.

Reducing risk for patients for who must attend

When a patient has to attend, the amount of contact time will be reduced to a minimum. For example history taking can be performed over the phone in a different room. A distance of two metres will be kept from the patient, until clinical examination requires otherwise. The examination will be kept brief and concise, minimising any procedures that are not entirely necessary. Exacting hygiene standards will be followed throughout. Every effort will be made to defer immunosuppressed, vulnerable and high-risk patients making use of video facilities where possible.

Emergency services

As the crisis develops it’s likely that ophthalmology services will be reduced as resources are directed to front line care of COVID 19 patients. Eye services will not cease completely, and priority will be given to anyone whose condition is life or sight threatening.

This blog is contributed by Gurjeet Jutley.

October, 2019

Cataracts are one of the most common causes of reversible blindness in the world, with around 10 million cataract operations performed globally each year.

The natural lens in your eye becomes cloudy or opaque, causing scattering of light and diminished rays entering the eye. This makes it harder to see clearly, causing visual morbidity.

Many types of cataracts exist, including nuclear sclerotic, cortical and posterior subcapsular.

Nuclear Sclerotic Cataracts
Nuclear sclerotic cataracts are the type that we usually associate with age. Approximately 25% of people develop these cataracts by the age of 75.

Symptoms that might occur include:

  • Blurry, unfocused or unclear vision
  • Colour contrast may change might look different,
  • Glare, particularly for night driving

This type of cataract tends to have an insidious progression over years.

Cortical Cataracts
Conceptualise the natural lens as a peanut M&M. Beyond the outer hard shell, is the inner chocolate (which is equivalent of the lens cortex in this comparison). Cortical cataracts occur when this area becomes more opaque and can be directly due to the affects of Father time.

Under the microscope, cortical cataracts are characterised by white streaks or wedge-shaped opacities (called cortical spokes) which grow on inwards toward the middle of your eye. This leads to symptoms such as:

  • Problems with light glare
  • Contrast and depth perception

The exact impact on vision is dependent on exactly where the lens opacity is found.

Posterior Subcapsular Cataracts
As the name suggests, posterior subcapsular cataracts form on the back of your lens, beneath the lens capsule (the outer coloured shell of the peanut M&M).

Symptoms can include increasing difficulty reading and difficulty seeing in low illumination. Conversely to nuclear sclerotic and cortical, this type is more commonly seen in younger age and can develop due to other systemic causes. This is especially true for those taking high doses of corticosteroids and diabetic patients.

To summarise, cataracts can be considered an inevitable part of living and surgery likely to be required by us all. Timings of corrective cataract surgery depends on:

  • Other pathologies
  • Symptoms
  • Patient’s choice

This blog is contributed by Gurjeet Jutley.

December, 2018

How gameplay can affect the eyes

Protracted periods of time in front of the computer concentrating on games can induce unpleasant symptoms including blurred vision, headaches, fatigue and eye discomfort. The primary reason is the reluctance to take breaks once fully immersed in the game. The focus of the eye constantly changes when concentrating on video screens, potentially causing eye fatigue.

The importance of breaks

Lack of blinking when fully immersed in computer games causes dryness and irritation. It is imperative to try having five-minute breaks every twenty minutes or so. Where possible, it is advisable to aim to have a six-foot minimum from the screen.

Children requiring eye assessment?

Ascertaining ocular symptoms from children is an extremely difficult task. One must look for subtle signs, including:

  • Squeezing the eyes together (‘squinting’)
  • Covering one of the eyes
  • Tilting the head
  • Sitting closer to the TV

The mainstay of managing children is to prevent amblyopia, so called ‘lazy eye’. The signs described may be early signs and it is critical to seek advice and assessment.

This blog is contributed by Gurjeet Jutley.

December, 2018

Without doubt vision has a major impact on the ability to drive safely on the roads. This is highlighted by guidance and restriction on driving by the DVLA. For example there are a range of conditions that should be brought to the attention of the DVLA in order to ascertain legality to drive. Simple advice should be followed to ensure safety is preserved.

Follow your health care advice

  • Use distance spectacles or contact lenses always
    • If possible, keep spare pair of spectacles in the car
  • Consider anti-reflective coating to reduce symptoms of glare from headlights
  • Avoid wearing tinted lenses in poor light conditions as they can make dark environments seem even darker.
  • When choosing intra-ocular lenses, consider the visual requirements prior to deciding. For example, patients who drive in the evenings with lots of lighting on motorways may be debilitated with glare. Lenses that may potentiate glare should be avoided.

Visual aids for driving

  • To optimise the field of vision, consider slimmer frames
  • It’s important to perform an Easterman’s visual field in order to ascertain if driving is permissible
  • It’s important to acknowledge that the rules of the road are different depending on the type of license required
  • Visual requirements must be met, including:
    • Reading 6/12 on the Snellen chart
    • Reading a post-2001 number plate from at least 20 metres away.

Essentially, driving should be ceased immediately if told to do so.

Keep the DVLA informed

It’s a legal obligation that the DVLA is notified if the visual requirements of vision are not met. Vision-related conditions that must be disclosed include new double vision, diabetic retinopathy, macular degeneration and glaucoma.

Tests could be needed

The DVLA will decide if further tests are required to determine the requirement to drive. Commonly, binocular visual-field tests are requested. Continual driving when told conversely is not endangering others, also poses risks of:

  • Refused car insurance
  • Fine
  • Legal action

This blog is contributed by Gurjeet Jutley.

October, 2018

A quick guide to astigmatism

The outer dome of the eye called the cornea is shaped like a football, with light rays bent uniformly to focus at the back of the eye. Astigmatism occurs when the curvature of the eye’s cornea (or lens) is not spherical: i.e. it’s shaped like a rugby ball. This affects the eye’s ability to focus light on the retina, leading to blurry and distorted vision. This is a minor condition and it can usually be corrected with:

  • Spectacles
  • Contact lenses
  • Surgery

Regular vs. irregular astigmatism

There are two types of astigmatism:

  • Regular: which can be managed by toric lenses
  • Irregular: usually requiring rigid gas permeable contact lenses

Although there are two types of astigmatism, there are three ways that vision can be impaired. These are hyperopic (far sightedness), myopic (near sightedness) and mixed (a combination of near and farsightedness).

 

What causes astigmatism?

In most cases, an individual is born with an irregularly shaped cornea or, far less commonly, the lens. However, it’s also possible for people to develop this condition later in life. Genetics may play a role and there is no real known way to prevent it from developing. Specific causes include:

  • Eye surgery, such as cataract surgery
  • Eye conditions, such as keratoconus and keratoglobus
  • Conditions that affect the eyelids that push down on the cornea.

 

Astigmatism symptoms

The symptoms of astigmatism may differ amongst individuals and range from:

  • Asymptomatic
  • Blurry and distorted vision
  • In childhood, if astigmatism isn’t corrected, a lazy eye (amblyopia) can occur.

This blog is contributed by Gurjeet Jutley.

August, 2018

A quick guide to glaucoma

Glaucoma is an eye condition that involves damage to the optic nerve. The optic nerve connects the eye with the brain. Glaucoma is commonly caused by the imbalance that leads to raised pressure of fluid in the front of the eye. The fluid increases pressure, and the condition is one of the most important causes of irreversible sight loss in the working aged population.

How glaucoma develops

One particularly worrying aspect of glaucoma is that initially it can be completely asymptomatic. The condition usually develops at a slow rate over many years, affecting the peripheral vision initially. Early signs of glaucoma can be ascertained during routine eye tests.

Main symptoms

The disease is typically bilateral, although this may be asymmetric meaning one eye is predominantly clinically affected. In acute glaucoma, development of symptoms is an emergency:

  • Nausea and vomiting
  • Intense eye pain
  • Headaches
  • Blurred vision
  • Red eye
  • Haloes

Types of glaucoma

Acute glaucoma is an ocular emergency: it is critical to seek help immediately. There are of course different types of glaucoma, including primary open-angle glaucoma, the most common form. This occurs slowly over the course of several years and involves the drainage channels gradually becoming inefficient at fluid egression. Broadly categorised, glaucoma can be open angle or closed angle, primary or secondary, adult onset or congenital.

Who is at risk of glaucoma?

Quite simply, anyone can manifest glaucoma. However various risk factors exist, including:

  • Age
  • Family History
  • Ethnicity
  • Existing medical conditions

Early diagnosis and early treatment is key: hence the importance of a robust screening program and adhering to regular check-ups.

Whilst glaucoma cannot be reversed, the progression can be arrested, utilising modalities such as eye drops, laser and surgery.

This blog is contributed by Gurjeet Jutley.