Birmingham Eye Trauma Terminology (BETT)terminology and classification of mechanical eye injuries

Ophthalmol Clin N Am 15 (2002) 139 – 143
Birmingham Eye Trauma Terminology (BETT):
terminology and classification of mechanical eye injuries
Ferenc Kuhn, MD, PhDa,b,c,d,*, Robert Morris, MDa,b,c,
C. Douglas Witherspoon, MDa,b,c
a
United States Eye Injury Registry, Birmingham, AL 35205, USA
Helen Keller Foundation for Research and Education, Birmingham, AL 35205, USA
c
Department of Ophthalmology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
d
University of Pécs, Pécs, H-7643, Hungary
b
Lacking a standardized terminology of eye injury
types, it is impossible to fulfill a very basic requirement in medicine: that all communications be unambiguous. Accurate interpretation of published research
results, which has an absolutely crucial role in determining how an individual patient with an eye injury
is treated, becomes difficult. The required triage
(decision-making process), involving all elements of
management, has a measurable risk of bias if there is
uncertainty regarding the type of injury encountered.
If the reader has the opportunity, time, and patience to review the entire article, not just the title
and the abstract, some of the ambiguities can be resolved; however, the reader commonly has limited
time or access, allowing the analysis of only the
abstract of the article. It is therefore crucial for all
authors to use standardized eye injury terms, which
permit a single interpretation.
An ideal ocular trauma terminology system
Review of the literature
Unfortunately, the ophthalmologist analyzing published research results finds it impossible to draw unambiguous conclusions if the studies he or she relies
upon were compiled without the language of ocular
traumatology having been standardized. Even a few
literature examples are sufficient to demonstrate the
consequences and implications of the use of eye injury
terms that lack a clear definition and that are open to
individual interpretation.
There are two types of problems: the terms themselves are ambiguous (Table 1) or they are potentially
accurate but are used inappropriately (Table 2).
* Corresponding author. Helen Keller Foundation for
Research and Education, 1201 11th Avenue South, Suite 300,
Birmingham, AL 35205, USA.
E-mail address: [email protected] (F. Kuhn).
Table 3 compares the requirements of an optimal
terminology system for mechanical eye injuries with
some of the findings in the literature. We have designed and introduced terms and definitions [Birmingham Eye Trauma Terminology (BETT)] that satisfy all
elements required by an ideal system. BETT achieves
the desired goals by:
Clarifying the issue of reference
Providing a clear definition for each injury type
(Table 4)
Placing each of these injury types within the
framework of a comprehensive system (Fig. 1)
The most important feature of BETT is that all of
its terms relate to the whole eyeball as the tissue of
reference. Before BETT, a ‘‘penetrating corneal
injury’’ could imply two vastly clinical conditions,
depending on the tissue of reference: (1) an injury
penetrating into the cornea (ie, a partial-thickness
0896-1549/02/$ – see front matter D 2002, Elsevier Science (USA). All rights reserved.
PII: S 0 8 9 6 - 1 5 4 9 ( 0 2 ) 0 0 0 0 4 - 4
140
Term [reference]
Interpretation
Clinical implication
Resolution
Blunt injury [2,3]
The consequences of the trauma are blunt.
The inflicting object is blunt.
Closed globe injury (contusion)
Open globe injury (rupture)
Contusion rupture [4]
? (How can an injury be contusion and a rupture?)
? (What kind of injury is it?
Contusion? Rupture?)
We must eliminate blunt from our
eye injury vocabulary and use either
of the two accurate and unambiguous
terms instead: contusion or rupture.
This term should not be used.
Blunt nonpenetrating globe injury [5]
? (Is there a sharp nonpenetrating injury? If so,
what is it? If not, why use the term blunt at all?)
? (How can an injury be blunt and penetrating?)
Blunt penetrating trauma [6]
Sharp laceration [7]
Blunt rupture [8]
? (Is there a laceration that is not sharp? If all lacerations
are sharp, why the distinction? If not, how do they differ?)
? (Aren’t all ruptures blunt? If so, why the distinction?
If not, how do they differ?)
This term should not be used.
? (What kind of injury is it?
Rupture? Penetrating?)
This term should not be used.
This term should not be used.
This term should not be used.
F. Kuhn et al / Ophthalmol Clin N Am 15 (2002) 139–143
Table 1
Literature review: ocular trauma terms difficult to interpret
F. Kuhn et al / Ophthalmol Clin N Am 15 (2002) 139–143
141
Table 2
Literature review: ocular trauma terms used inappropriately
Penetrating [9]
Penetrating [10]
Rupture [11,12]
Likely interpretation
by the reader
Original interpretation
in the article
Resolution
Injury with an
entrance wound
Injury with an
entrance wound
Any type of open
globe injury
Penetrating = perforating
Open globe injury caused
by impact of a blunt object
Any type of open globe
injury, including those caused
by intraocular foreign bodies
All penetrating injuries are open globe, but
not all open globe injuries are penetrating.
Penetrating and perforating injuries must be
distinguished because they have vastly
different management and prognostic
implications.
All ruptures are open globe, but not
all open globe injuries are ruptures.
Table 3
Ocular trauma terminology: an ideal system versus reality
What should be the case
What is the case
Each eye injury term has a unique definition.
It is exceptional that published studies provide definitions;
nor are these definitions required by editors.
The same term ( perforating) is used to describe two distinctly
different clinical conditions: an injury with a single (entrance)
wound [13] or one with both entrance and exit wounds [14].
The same type of injury (having an entrance and an exit wound)
is referred to as double penetrating [15], double-perforating [16],
and perforating [17].
No term can be used for describing two
different injury types.
No type of injury is described by different terms.
Table 4
Terms and definitions in BETT a
Term
Definition/interpretation
Explanation
Eyewall
Sclera and cornea
Though technically the eyewall has three coats posterior to
the limbus, for clinical and practical purposes, violation of
only the most external structure is taken into consideration.
Closed globe injury
Open globe injury
Contusion
No full-thickness wound of eyewall
Full-thickness wound of the eyewall
No (full-thickness) wound
Lamellar laceration
Rupture
Partial-thickness wound of the eyewall
Full-thickness wound of the eyewall
caused by a blunt object
Laceration
Full-thickness wound of the eyewall
caused by a sharp object
Entrance wound
Penetrating injury
Retained foreign object(s)
Perforating injury
a
Entrance and exit wounds
The injury results from direct energy delivery by the
object (eg, choroidal rupture) or from the changes in
the shape of the globe (eg, angle recession).
The wound of the eyewall is not ‘‘through’’ but ‘‘into.’’
Because the eye is filled with incompressible liquid,
the impact results in momentary increase of the
intraoccular pressure. The eyewall yields at its weakest
point (at the impact site or elsewhere; eg, an old cataract
wound dehisces even though the impact occurred elsewhere;
The actual wound is produced by an inside-out mechanism.
The wound occurs at the impact site by an
outside-in mechanism.
If more than one wound is present, each must have been
caused by a different agent.
Technically this a penetrating injury but grouped
separately because of different clinical implications.
Both wounds are caused by the same agent.
Some injuries remain difficult to classify (an intravitreal BB pellet) whereas technically an intraocular foreign body (IOFB)
injury is a blunt object that requires great force to enter the eye, involving an element of rupture. In such situations, the
ophthalmologist should describe the injury as ‘‘mixed’’ (ie, rupture with an IOFB) or select the most serious type of the
mechanisms involved.
142
F. Kuhn et al / Ophthalmol Clin N Am 15 (2002) 139–143
Fig. 1. BETT. The thick boxes contain the diagnoses used in clinical practice.
corneal wound: a closed globe injury) or (2) an injury
penetrating into the globe (ie, a full-thickness corneal
wound: an open globe injury). In BETT, a penetrating
injury is unambiguously an open globe injury with a
single (entrance) wound; corneal simply refers to
wound location.
BETT [1] has been endorsed by several organizations (eg, American Academy of Ophthalmology;
International Society of Ocular Trauma; Retina Society; United States Eye Injury Registry and its 32
international affiliates; Vitreous Society; and the
World Eye Injury Registry) and is mandatory for all
submission by several journals (eg, Graefe’s Archives
for Clinical and Experimental Ophthalmology;
Journal of Eye Trauma; Klinische Monatsblätter für
Augenheilkunde; and Ophthalmology).
With BETT becoming the language of everyday
clinical practice, we can reasonably hope to eliminate
all ambiguities in our communications in the field of
ocular traumatology.
References
[1] Kuhn F, Morris R, Witherspoon CD, Heimann K, Jeffers
J, Treister G. A standardized classification of ocular
trauma terminology. Ophthalmology 1996;103:240 – 3.
[2] Joseph E, Zak R, Smith S, Best W, Gamelli R, Dries D.
Predictors of blinding or serious eye injury in blunt
trauma. J Eye Trauma 1992;33:19 – 24.
[3] Russell S, Olsen K, Folk J. Predictors of scleral rupture
and the role of vitrectomy in severe blunt ocular trauma.
Am J Ophthalmol 1988;105:253 – 7.
[4] Eide N, Syrdalen P. Contusion rupture of the globe.
Acta Ophthalmol 1987;182S:169 – 71.
[5] Liggett PE, Gauderman WJ, Moreira CM, Barlow W,
Green RL, Ryan SJ. Pars plana vitrectomy for acute
retinal detachment in penetrating ocular injuries. Arch
Ophthalmol 1990;108:1724 – 8.
[6] Meredith TA, Gordon PA. Pars plana vitrectomy for
severe penetrating injury with posterior segment involvement. Am J Ophthalmol 1987;103:549 – 54.
[7] de Juan E, Sternberg P Jr, Michels RG. Penetrating
ocular injuries. Ophthalmology 1983;90:1318 – 22.
[8] Kylstra JA, Lamkin JC, Runyan DK. Clinical predictors of scleral rupture after blunt ocular trauma. Am J
Ophthalmol 1993;115:530 – 5.
[9] de Juan E, Sternberg P Jr, Michels R, Auer C. Evaluation of vitrectomy in penetrating ocular trauma. A casecontrol study. Arch Ophthalmol 1984;102:1160 – 3.
[10] Hassett P, Kelleher C. The epidemiology of occupational penetrating eye injuries in Ireland. Occup Med
1994;44:209 – 11.
[11] Pump-Schmidt C, Behrens-Baumann W. Changes in the
epidemiology of ruptured globe eye injuries due to societal changes. Ophthalmologica 1999;213:380 – 6.
[12] Rudd J, Jaeger E, Freitag S, Jeffers J. Traumatically
F. Kuhn et al / Ophthalmol Clin N Am 15 (2002) 139–143
ruptured globes in children. J Ped Ophthalmol Strab
1994;31:307 – 311v.
[13] Punnonen E, Laatikainen L. Prognosis of perforating
eye injuries with intraocular foreign bodies. Acta Ophthalmol 1989;66:483 – 91.
[14] Ramsay RC, Knobloch WH. Ocular perforation following retrobulbar anesthesia for retinal detachment
surgery. Am J Ophthalmol 1978;86:61 – 4.
[15] Ramsay RC, Cantrill HL, Knobloch WH. Vitrectomy
143
for double penetrating ocular injuries. Am J Ophthalmol 1985;100:586 – 9.
[16] Topping TM, Abrams GW, Machemer R. Experimental double-perforating injury of the posterior segment
in rabbit eyes. Arch Ophthalmol 1979;97:735 – 42.
[17] Hutton -WL, Fuller DG. Factors influencing final visual
results in severely injured eyes. Am J Ophthalmol
1984;97:715 – 22.