Sep 2016

Focus on
Eye Research
Thyroid eye disease, epiphora,
and ptosis after ocular surgery
CHUNDURY RV ET AL. ORBITAL RADIATION
THERAPY IN THYROID EYE DISEASE
Ophthal Plast Reconstr Surg 2016; 32:83-89
As the role of supportive therapies such as selenium
and biologic agents in the treatment of thyroid eye
disease (TED) continue to evolve, orbital radiation
therapy (ORT) is a longstanding, but contentious
mode of medical treatment of TED. This review
considered a wealth of existing data, and its
shortcomings, in an effort to understand the role of
ORT in TED.
A dose of 20Gy delivered to each eye in 10 fractions
over 10-12 days is common, but different sources of
radiation, classification schemes and compounding
effects of adjunctive glucocorticoid use means
that comparisons between studies is challenging.
This paper considers all the available data as a
whole and concludes that between 50-90% of mild
moderate TED patients treated with ORT will have
some improvement in motility, proptosis and clinical
activity when it is given early in the disease. ORT may
also help prevent vision-threatening complications
such as compressive optic neuropathy. The beneficial
effect of ORT can be enhanced with concomitant use
of glucocorticoids. Re-irradiation has been used with
some success, however there is little data regarding
safety and efficacy.
Much data exists to demonstrate ORT is safe in
patients without predisposition to retinopathy.
Patients with retinopathy risk factors, particularly
severe hypertension and diabetes may be at higher
risk. The risk of cataract development appears very
low.
The theoretical increased risk of brain and bone
malignancy has not been observed in large
retrospective studies with long-term follow up,
although some still limit the use of ORT to patients
greater than 30-35 years because of this concern.
The authors concluded that although ORT is rarely
used as a first-line agent, it is a safe option in the
armamentarium available for management of active
TED.
MANSUR C ET AL. EVALUATION AND
MANAGEMENT OF CHEMOTHERAPY-INDUCED
EPIPHORA, PUNCTAL AND CANALICULAR
STENOSIS, AND NASOLACRIMAL OBSTRUCTION.
OPHTHAL PLAST RECONSTUCT SURG 2016; JULY
(EPUB AHEAD OF PRINT).
Epiphora is a recognised adverse effect of chemo
therapeutic agents whose extent is probably
under appreciated by both ophthalmologists and
oncologists.
This elegant literature review identifies various
agents known to cause epiphora, the mechanisms
and appropriate management paradigms.
Most commonly associated are 5-Fluorouracil
(5-FU) and Docetaxel which cause dose dependent
epiphora in up to 50 and 64% of patients
respectively; this is reversible with prompt
treatment. The agents are secreted in tears, and
appear to cause canalicular, lacrimal sac and
nasolacrimal duct fibrosis.
A trial of corticosteroid with probe and syringe
appears effective in cases of low dose or short-term
treatment, but patients receiving high frequent
dose 5-FU or docetaxel, silicone stenting at the
first sign of recurrent or progressive canalicular
stenosis can prevent irreversible canalicular scarring.
Unfortunately, prophylactic topical corticosteroid
have been proven to be ineffective.
Other agents less commonly found to cause
epiphora secondary to nasolacrimal obstruction
included radioactive iodine (I-131), which at high
doses is preferentially taken up by nasal tissue.
Females and those over 45 years old were more
likely to develop epiphora.
F-1, an oral drug composed of tegafur (pro-drug of
5-FU) and oteracil, as well as mitomycin C (MMC),
also cause stenosis of the lacrimal drainage pathway
at the punctum, canaliculus or distal nasolacrial
duct. Onset of effect is within three months.
Interestingly MMC is often used to prevent fibrosis
DR JAMES SLATTERY*
of the lacrimal drainage system after surgery.
Epiphora is the second most common side effect
of Imatinib. Unlike other agents, the mechanism
is via hypersecretion and mechanical blockage of
puncta by conjunctivochalasis coupled with pump
dysfunction secondary to periorbital oedema.
Practitioners must be aware of stenosis or
obstruction of the lacrimal drainage system as
a possible adverse effect of these agents. Early
recognition and appropriate treatment may obviate
the need for more invasive and complicated
surgical treatment and so evaluation of drug
type, and thus likely cause of epiphora, with
prompt appropriate referral is critical.
GODFREY K. BLEPHAROPTOSIS FOLLOWING
OCULAR SURGERY: IDENTIFYING RISK FACTORS
Curr Opin Ophthalmol 2016;27:31-7
Ptosis is common following ocular surgical
procedures. Nearly one third of acquired ptosis is
postsurgical. This literature review attempts to
identify the incidence of this poorly understood
complication post ocular surgery, and shed light on
its likely contributing factors.
Cataract surgery is the most commonly performed
ocular surgery and randomised prospective studies
document the incidence of post cataract ptosis
to be somewhere around 6-12%. Use of a bridal
suture in addition to an eyelid speculum nearly
doubles the risk. The incidence is similarly around
10% post refractive surgery, such as laser in situ
keratomileusis as well as trabeculectomy, as
documented in the collaborative initial glaucoma
treatment study (CIGTS). Adjuvant use of
mitomycin C (MMC) increased the risk. There
are documented cases of ptosis following serial
intravitreal injections of anti-vascular endothelial
growth factor and steroid, but appropriately
powered studies are lacking.
Ptosis can be caused by interruption to any of
the delicate structural and functional relationships
of the eyelids although levator dehiscence is likely
the common denominator. Several studies recognise
individual patient anatomy to confer highest risk of
postoperative ptosis and it is probable that patients
with tenuous levator attachment and subclinical
ptosis are at highest risk. Operative time may play a
role but there is no consensus in the literature.
Theories such as a tight speculum reducing blood
flow to the levator muscle, horizontal eyelid stretch
and contraction of orbicularis against speculum
causing dehiscence have been postulated, or
that compression of myoneural or myovascular
structures contributes. Myotoxicity from local
anaesthetics has also been suggested, but has not
been validated in the literature.
Risk can be minimised with use of topical
anaesthetics and avoidance of bridal sutures and
specula where possible. If a speculum is required,
using the shortest possible horizontal arm and
reduced vertical eyelid displacement should be
considered. Studies have shown disposable specula
are significantly less stiff than reusable ones, which
may reduce the risk.
Even with optimum technique, ptosis can still occur
and this should be discussed during informed
consent. Repair is possible with high rates of
success but requires an additional surgical
procedure. ▀
ABOUT THE AUTHOR:
* Dr James Slattery holds
an MBBS, PhD, B Sci
(Biomed), and is an
oculoplastics fellow
at the University of
Auckland. He trained
in Adelaide, South
Australia.
Labour of love with touch
of madness
BY SIMON ESKOW
What would inspire someone who
doesn’t know French to create the first
translation of a 450-page book written
in that language?
“I’ve got no bloody idea,” says Dr Philip
Polkinghorne, who accomplished that very task,
laughing. “It’s the stupidest thing I ever did.”
Polkinghorne, who describes his grasp of French
as “absolutely useless”, finished the impressive
task of translating Le Decollement de La rétine:
pathogénie, traitement – or Detachment of the
retina: pathogenesis, treatment – in mid-2015. The
400-page tome was authored by the pioneering
Swiss ophthalmologist, Jules Gonin (1870-
1935), who discovered through detailed clinical
observation that the retinal tear was the cause,
and not the result, of retinal detachment, contrary
to prevailing theories of the time.
“People had done all sorts of hocus pocus
before that time,” Polkinghorne says. “But Gonin’s
was the first, if you like, thought-out, scientific
approach to the problem.”
Polkinghorne, a surgeon with Auckland Eye
and an associate professor at the University of
Auckland, embarked on his translation after
spotting a copy on the University of Auckland’s
head of ophthalmology Professor Charles
McGhee’s bookshelf. Polkinghorne has been a
member of the international Club Jules Gonin
for 20 years and was surprised to see a copy
of the original French version as relatively few
are in circulation. Despite the linguistic barrier,
Polkinghorne borrowed the copy, scanned the
400 pages to a PDF file and converted it to Word,
and began the page-by-page, word-by-word
translation, using “a whole lot of search engines”.
In the first section, Gonin details the history of
ophthalmological theories of retinal detachments,
with critique and a presentation of his own theory.
“People did some crazy things for retinal
detachment,” Polkinghorne says. “For example
they cut holes in the iris and injected all sorts of
things into the eye like mercury and cyanide, and
under the conjunctiva.”
The latter section of the book describes
treatment for retinal detachment and Gonin’s
approach using thermocauterisation.
The whole project took Polkinghorne more than
a year.
“I think it took me about 10 hours per page. Once I
got into it, I couldn’t stop. It became an obsession.”
Professor Jules Gonin - brilliant but divisive
A/Prof Philip Polkinghorne says translating Jules Gonin’s book became
an obsession
Translation was hampered by the fact that Gonin
wrote one hundred years ago, which means some of
his French is antiquated. Furthermore, Polkinghorne
had to determine the meaning of outmoded
technical terms by their context. The French word
for “vitreous”, for example, was translated in
search engines as “glass”. Another example was
a term translated as “electro-coagulation”, which
Polkinghorne knew to mean “diathermy.”
Modern technology and hard work carried
Polkinghorne only so far.
“Sometimes it was impossible for me to work it
out, so, I talked to a lot of French speakers,” he says.
A particular difficulty arose from determining the
unit Gonin used in measuring IOP.
“He was obviously talking about the pressure
of the eye but it wasn’t mm Hg (millimetres of
mercury), but a symbol that I had no clue what it
meant.”
Among his French speaking consultants were
Associate Professors Gordon Sanderson and
Ivan Goldberg. It was A/Prof Goldberg who put
Polkinghorne in touch with a glaucoma subspecialist
in France, who revealed the symbol to
represent mm of H2O.
“A lot of people helped me with those difficult
translations.”
Mind you, other difficulties still remain, says
Polkinghorne, such as identifying some of the
drugs Gonin references, which went under trade
names from companies long-gone.
Polkinghorne’s efforts took him as far as London
to visit Dr Richard Keeler, a self-styled archivist
with a large collection of books, photographs
and other material covering the history of
ophthalmology. Dr Keeler supplied Polkinghorne
with a rare image of Gonin from a pamphlet about
a presentation Gonin made to the Oxford Club at
the height of the doctor’s career in the early 1930s.
The pamphlet had misspelled Gonin’s name,
perhaps because Gonin was well-known to have
had a somewhat bumptious relationship with
many of his peers.
“There were people who said he was despicable.
He certainly wasn’t the world’s nicest man,” says
Polkinghorne. “In his book, he calls people the
most outrageous things. He names the people and
calls them charlatans. Known figures! So he did
take on people. So people did the exact same thing
back to him.”
An electronic version of Polkinghorne’s
translation is likely to be posted on the Club Jules
Gonin website. Polkinghorne says he plans to print
a small number of copies himself. ▀
OSO Congress double bill
The Orthokeratology Society of Oceania
(OSO) will be holding its 12th Congress
from Friday 23 to Sunday 25 September at
the Surfers Paradise Marriott Resort & Spa, Gold
Coast, Australia. This year, for the first time,
OSO will also be hosting the 5th Congress of the
International Academy of Orthokeratology.
OSO, which covers New Zealand, Australia
and some parts of the South Pacific, has been
around for quite some time, says Hamilton
optometrist Jagrut Lallu, one of the OSO
Congress’ organising committee. “As new
groups began to spring up globally, they decided
to come together annually to share their
knowledge and expertise. This year is the first
time this global meeting has come to Oceania.”
This is an event not to be missed for anyone
interested in orthokeratology, says Lallu. “This
is a big meeting. We normally have around
200 delegates at our biennial congress, but
because of this international meeting we are
expecting many, many more. Oceania does a lot
of research into ortho-k, but we are expecting
delegations from China, the USA, Europe, Russia
and South Africa – literally, all over the world.
It’s the first time we’ve hosted it and to have
this many global experts in one location is
pretty special.”
The three-day event will include workshops
around fittings, scleral lenses, trouble shooting
and a beginners boot camp among other things,
plus Friday night drinks with the speakers and a
Saturday night gala dinner.
There is still time to register, and a full rundown
of the programme is available, online at
www.osa.net.au ▀
20 NEW ZEALAND OPTICS September 2016