ULTRAVIOLET KERATITIS

“Regulus”, oil on canvas, 1828-1837, J.M.W Turner

The exact origins of the great conflict between Rome and Carthage are uncertain and obscure. While the record of the Second and Third Punic wars are relatively well documented those of the earlier First Punic War (264 - 241 B.C) are frustratingly fragmentary. Although what records we have are meager, one thing we do discern is the first hint of the uncompromising and brutal attitude of Roman policy in the conduct of war. War to Rome was a literal matter of life and death, victory or annihilation - there was no middle ground, no compromise from the Roman Republic. The Carthaginians came to realize what they were up against at an early stage. They learnt quickly that no quarter would be given, none would be expected. While the First Punic war ended in somewhat of a stalemate, Carthage understood that this would not be the end of the matter. They were now locked into a course of survival or death, no matter how long this would take to determine. Roman wars only ended when the adversary had accepted unconditional surrender. To Roman eyes the only alternative to this outcome was defeat on the very same terms. The Carthaginian attitude to warfare on the other hand was a more traditional one. They expected a war to be ended by negotiated treaty, commensurate with the balance of power then held by the two sides at the moment of the negotiations. They did not anticipate that a challenge to another power would require the utter destruction of that power to the point that it could not harm them again in the future, and much less that a foreign power would impose such terms on them! After 9 years of bitter conflict on the sea and in Sicily, Rome finally felt strong enough to mount a full scale invasion of the Carthaginian homelands in North Africa. In 256 B.C the Roman Consuls for that year, Lucius Manlius Vulso and Marcus Atilius Regulus, each led an army onto the African mainland.

The Consuls’ invasion fleets landed near the city of Aspis, and immediately this city was put to siege. Having captured it Rome had secured a base from which it could now pursue the war into the Carthaginian hinterland and ultimately threaten Carthage itself. Vulso took one legion back to Rome together with many prisoners and loot. Regulus was left to carry on the war with his army in Africa. At first he swept all before him, marauding along the coast inching ever closer to Carthage. It was at this desperate hour however that the Carthaginians engineered a masterstroke of counterattack. They employed a brilliant Greek mercenary general, said to be Spartan trained, by the name of Xanthippus. Xanthippus proved a more than capable general. The exact location is unknown but at a place somewhere near modern day Tunis he clashed with Regulus’s army in an engagement that history now records as the Battle of Tunis. It is in this battle that elephants first appear in history as beasts of war. We need to understand the significance of this development in the context of the Third century B.C. Many Romans would not have seen an elephant before in their lives and the sight of these immense creatures leading a massed attack would have been very disorientating and quite terrifying to many. A modern comparison of this kind of psychological impact could perhaps be made with many of the troops of the Great War who had never before seen a “flying machine”. By a combination of the clever use of elephants, and skillful generalship, Regulus was defeated and taken into captivity along with much of his army. Xanthippus, then somewhat mysteriously disappears from history, some saying that he had so earned the envy and jealousy of the native Carthaginian generals that he was required to flee back to Greece, in fear of his life.

The Carthaginians true to their idea of warfare then attempted to open negotiations with Rome. Exhausted by 9 years of war, they assumed that this would be a good time to negotiate terms and bring hostilities to a mutually beneficial end. They did not however understand the military psyche of the Roman Republic. They sent Regulus back to Rome, to deliver their terms. Regulus was bound on sacred oath to return to Carthage with the Senate and People’s response. He arrived in Rome where he was received coolly. His shame diminished and his prestige grew however as he spoke to the Senate who listened to him in stony silence. True to Roman principles, he argued passionately that Rome must not accept any of the Carthaginian terms. The defeat in Africa was merely a temporary setback, the war must be carried on to its final and inevitable conclusion - total victory with a Carthaginian surrender without terms! The Roman Senate, unfortunately for Regulus, agreed. They refused terms completely. True to his sacred oath Regulus then sailed back to Carthage even though he knew the unwelcome news would in all likelihood bring him cruel torture and death. The Carthaginians were astonished and outraged - Rome refused even speak with them unless they - the recent victors on the field of battle - submitted to total surrender! In brutal retaliation Regulus was condemned to death. One ancient source has it that his eyelids were cut from his eyes, and he was then forced to look directly at the Sun until in indescribable agony he went completely blind. He was then trampled to death by enraged elephants. When the Senate heard of Regulus’ fate, true to the ancient code of an “eye for an eye, a tooth for a tooth”, they sent a number of Carthaginian captives to Regulus’ widow, who had them so brutally tortured that they died.

The war with Carthage would continue for another 14 longs years. Though Rome did not directly invade North Africa again, it did, in a series of stunning sea victories, manage to take Sicily and Sardinia from Carthage. The war ended in somewhat of a stalemate in 241 B.C. with both sides too exhausted to continue the struggle. For Carthage this seemed a victory - but for Rome it was only a temporary withdrawal. Over the next century two further vicious and protracted wars would be fought until Carthage was finally crushed so completely that it disappears from the historical record.

The First Punic war showed the rest of the Mediterranean world what it now meant to defy Rome - submission or annihilation. The story of Regulus became legend, a legend of Roman courage and valor that echoed down through the centuries. Over two millennia later, J.M.W Turner, ever the brilliant innovator of Nineteenth century British art would capture the brutal nature of the First Punic War in his “Regulus”, painted between 1828 and 1837. He portrayed a scene of Ancient Carthage as if seen through the lidless eyes of Regulus. Though there is a sense of late evening, the glare of the setting Sun when looked at directly is still blinding - literally. We see the setting Sun as if we were Regulus - his last vision of life - in the words of the magisterial Simon Schama - as a “path of kinetic agony of torturing brilliance”. Turner was never quite satisfied it seems that he had achieved quite the torturing brilliance he wanted to convey. Schama continues, “When he came to re-work the painting in public years later, he appalled the bystanders by attacking it with a palate loaded with lead white. He did so over and over until the blare of brilliance was physically painful, the white out of life that happens to us when we’ve been staring at the Sun for too long. Turner was starting to paint from inside the eye”.

In times gone by Ultraviolent keratitis could be a permanently blinding injury, especially if you carried unwelcome news to your victors in battle! Today fortunately this injury is most commonly seen as a result of the welder’s arc - a much more minor and fortunately reversible torture!

ULTRAVIOLET KERATITIS

Introduction

UV light is the most common cause of radiation injury to the eye.

UV light burns to the eye are described by the term “Ultraviolet Keratitis”, but more commonly used synonyms include Snow blindness and Flash burn.

Most commonly this injury is seen as a result of welding by patients not using appropriate protective eye glasses.

Treatment priority will be analgesia

Most injuries will heal spontaneously within 24 - 72 hours of the exposure.

Pathophysiology

The cornea largely absorbs UV radiation.

UV radiation damage to the corneal epithelium can be cumulative, similar to the effects seen with dermal epithelium (i.e sunburn).

The ozone in the atmosphere effectively filters most of the harmful UV radiation of wavelengths shorter than 290 nm; natural UV sources, such as the sun, rarely cause injury after short exposures. However, unprotected exposures to the sun or solar eclipses or exposure to the sun on highly reflective snow fields at high elevation can lead to direct corneal epithelial injury. The latter clinical scenario is known as snow blindness.

Human generated sources of UV radiation also cause corneal damage. Injury from a welder’s arc commonly is known as flash burn.

Other sources of UV radiation injury include sun tanning beds, carbon arcs, photographic flood lamps, lightning, electric sparks, and halogen lamps.

Prolonged exposures to UV radiation can lead to chronic solar toxicity, which is associated with several ocular surface disorders, e.g. pinguecula, pterygium, climatic droplet keratopathy, and even squamous metaplasia and carcinoma.

UV rays irritate the superficial corneal epithelium, causing inhibition of mitosis, production of nuclear fragmentation, and loosening of the epithelial layer.

An inflammatory response occurs, involving edema and congestion of the conjunctiva and a stippling of the corneal epithelium known as superficial punctate keratitis (SPK). SPK is a nonspecific corneal condition associated with many different ocular disorders. It is characterized by multiple pinpoint defects in the superficial corneal epithelium, which stain with fluorescein. In severe cases SPK may be followed by total epithelial desquamation, with conjunctival chemosis, lacrimation and blepharospasm.

Re-epithelialization usually occurs within 24-72 hours

Long-term sequelae are uncommon.

SPK effects are mild when compared with the severe effects seen with corneal damage caused by alkaline or acidic chemicals.

Involvement of the lens is rare and occurs only after intense exposures.

In general, ocular pain and decreased visual acuity occurs 6-12 hours after the injury. This lag time involves an unexplained pattern of corneal sensory loss and return and some theories suggest that it may indicate a photochemical injury rather than a thermal injury to the cornea.

Clinical Features

The commonest presentation of this problem to the ED is “flash burns” due to arc welding.

UV radiation damage to the superficial corneal epithelium, usually heals spontaneously within 24 - 72 hours of the exposure.

Long-term sequelae, which may result from secondary infection of damaged epithelium are rare.

Important points of history:

1. History of exposure to an intense ultraviolet source:

● As symptoms can be delayed 6 - 12 hours post exposure, patients may not always associate their symptoms with their exposure to the ultraviolet source.

● Enquire as to whether any protective eye glasses were being worn.

Document information regarding the nature and duration of the exposure is important. Workers compensation issues may require this documentation, and the information is often important for workplace safety education programs.

2. Presenting symptoms will include:

● Intense pain

● Watering eyes

● Photophobia

● Blurring of vision

Important points of examination:

Diffuse superficial epithelial defects (pinprick appearance) of the cornea seen in Ultraviolet burns of the cornea, (eMedicine)

Features seen on examination will include:

1. Significant conjunctival hyperemia is usually seen

2. Blepharospasm

3. Photophobia

4. There may be some mild lid and conjunctival edema

5. Loss of visual acuity

● Record the visual acuity in both eyes, after local anesthetic drops have been given.

6. Check that there is no co-incident foreign body.

7. Flourescein staining:

● This reveals diffuse, coarse superficial epithelial defects (pinprick appearance) of the cornea, (as shown above).

Investigations

None are necessary in clear cut cases.

Management

1. Analgesia:

● Administer topical anesthetic drops:

♥ This usually gives prompt and dramatic relief.

♥ Note however that repeated use retards epithelial healing and may lead to corneal ulcer formation.

They will also predispose to secondary traumatic injury.

Local anesthetic agents therefore should not to be given to the patient to take home.

● Oral analgesics may also be necessary.

2. Cycloplegic drops:

● Administer a short-acting cycloplegic drop (e.g cyclopentolate 1%) to relieve the pain of reflex ciliary spasm.

3. Antibiotics:

● Chloromycetin drops should be given for 48 hours.

4. Steroids:

● Never treat UV keratitis with steroids; the outcome may be disastrous if a concomitant herpetic ocular lesion is present.

5. Topical vasoconstrictors:

● Topical vasoconstrictors such as Naphazoline may also be considered.

6. Lubricating ointment:

● Lubricating ointments may give some additional symptomatic relief.

● Hypromellose gel is one option.

7. Sunglasses:

● Patient should wear sunglasses till symptoms resolves, to protect the eyes following the administration of local anesthetic drops. These will also provide protection from aggravating light, especially if they have received any cycloplegic agents.

● They should be advised against driving home.

Disposition

Ophthalmologic consultation usually is not necessary for this condition but may be obtained at the if there are any concerns or if vision loss or substantial healing has not occurred within 24-48 hours.

The local doctor should be able to review the patient in 24 hours.

References

1. Ultraviolet Keratitis, eMedicine Website, August 2013.

2. Eye trauma: ultraviolet burn (flash burn) in eTG, Emergency Medicine, version 1, 2008.

Dr J Hayes Reviewed September 2013.