Ординатура / Офтальмология / Английские материалы / Ocular Traumatology_Kuhn_2008
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410 Ferenc Kuhn, Robert Morris, C. Douglas Witherspoon
Table 2.15.2 Approaches to TKP vitrectomy. AS anterior segment surgeon, PS posterior segment surgeon
Single surgeon |
Teamwork: AS and PS |
Advantage Surgical decisions, which could otherwise fall under the competence of the other surgeon, are easier to make
Less time is wasted as there is no need to repeatedly switch between AS and PS
The responsibility for a surgical problem is easy to determine
The experience gained from the case is complete3
DisadvanSurgery is long and exhausting; it tage requires hours of uninterrupted con-
centration and brings many difficult challenges
The PS is less knowledgeable about all aspects of PK than an AS would be
All pathologies, whether in the anterior or posterior segment, receive expert treatment
Both surgeons have a “break” during the operation
Occasionally, decisions would need to be made by the other surgeon, who may not be readily available
Conflicts regarding certain maneuvers may arise as the other surgeon would prefer a different solution
The overall time of surgery may be longer
3 If two surgeons are involved, neither is likely to stay in the OR throughout the entire procedure; thus, neither gains from the knowledge of the other surgeon.
the retinal problems. It is the condition of the macula that primarily determines the functional success.
A corneal graft that subsequently becomes opaque can usually be replaced; conversely, damage to the postequatorial retina (e.g., detachment with severe PVR) often cannot be reversed.
2.15 Injury Involving the Entire Globe |
411 |
2.15.3.1.2The Procedure
The surgical steps are summarized in Table 2.15.3.
Table 2.15.3 A brief overview of the surgical steps during TKP vitrectomy
Procedure |
Comment |
Surgeona |
Designing the |
All factors, such as history, evaluation results, equip- |
PS, or PS |
surgical plan |
ment availability, patient desire, etc., must be carefully |
and AS |
|
weighed; if two teams are involved, a mutually agree- |
|
|
able plan and a clear understanding of “who does |
|
|
what, when, and how” must be established |
|
Placement of |
3 mm from the limbus; a long cannula4 should be |
PS |
the pars plana |
used; the infusion should not be turned on until the |
|
infusion |
position of its tip is verified (see Chap. 2.9) |
|
Preparation of |
This can alternatively be done later; if done at this |
PS |
the working |
stage, the sclerotomies should be plugged until |
|
sclerotomies |
vitrectomy commences. As in almost all cases, the two |
|
|
incisions should be ~170º apart to allow for maximum |
|
|
intraocular maneuverability. It is advisable to consider |
|
|
using a bimanual technique: a fourth sclerotomy may |
|
|
have to be prepared for the independent light source. |
|
|
The exact location for this sclerotomy is best deter- |
|
|
mined after the initial intraocular examination |
|
Placement of a |
Its use is highly recommended to provide stability dur- |
PS or AS |
Flieringa ring |
ing the corneal maneuvers. The size must be carefully |
|
|
selected to avoid interference with the sclerotomies, |
|
|
and it must be securely fixed to the sclera, not to the |
|
|
conjunctiva |
|
Selection of the |
The diameter of the trephine for the corneal bed |
AS |
keratome of |
should be either 1/4 mm larger than or equal to the di- |
|
proper size |
ameter of the TKP. This allows easy TKP placement yet |
|
|
prevents leakage during vitrectomy. A relatively large |
|
|
button is advised: if the PK needs to be repeated later, |
|
|
this should be smaller than the size of the first one |
|
a If a “team”, rather than a single surgeon, performs the operation; otherwise, as mentioned above, a posterior segment specialist should be the surgeon
4 6 or even 7 mm
412 Ferenc Kuhn, Robert Morris, C. Douglas Witherspoon
Table 2.15.3 (continued) A brief overview of the surgical steps during TKP vitrectomy
Procedure |
Comment |
Surgeona |
Removal of the |
The standard PK rules are followed |
AS |
button |
|
|
Suture fixation of |
If the Eckhard model is used, the number and type of |
AS |
the TKP |
sutures are entirely at the surgeon’s discretion. The |
|
|
Landers model has six predetermined holes; however, |
|
|
two (instead of six) limbus-parallel sutures, partial |
|
|
thickness in the cornea, suffice: each suture encom- |
|
|
passes two holes [8]. The use of 8-0 nylon sutures is |
|
|
recommended |
|
Anterior segment |
Removal of blood, iris, and pupillary membranes, |
AS |
reconstruction as |
injured lens, even IOL if deemed necessary; freeing |
|
needed |
the angle, etc. If the pupil is narrow, adrenalin drops |
|
|
can be instilled directly or iris retractors can be used |
|
|
(see Chap. 2.9). The time the eye is open should be |
|
|
minimized to reduce the ECH risk; the iris diaphragm |
|
|
must not be reconstructed at this point to allow |
|
|
unhindered view of the posterior segment |
|
Placement of an |
This is unavoidable if the pars plana infusion cannula’s |
PS |
AC infusion |
position could not be reliably verified; once it is, the |
|
|
AC maintainer can be removed |
|
Vitreoretinal |
All necessary and possible steps must be taken to |
AS |
surgery (see |
achieve retinal attachment, including silicone oil |
|
Chaps. 2.4−2.9 |
tamponade. Freeing the ciliary body from mem- |
|
and 2.10−2.14 for |
branes and reattaching it if it is detached are crucial. |
|
details) |
If silicone oil is injected,5 this should be done either |
|
|
at the conclusion of vitrectomy once the AC has been |
|
|
filled with viscoelastics6, or the BSS−air−silicone oil |
|
|
exchanges are performed after the corneal graft is |
|
|
in place. In either case, the sclerotomies are only |
|
|
plugged, not sutured, and the infusion cannula also |
|
|
remains in place |
|
5 Which is the vast majority of the cases
6 The AS is asked not to irrigate in the AC with BSS after this point.
|
2.15 Injury Involving the Entire Globe |
413 |
|
Table 2.15.3 (continued) A brief overview of the surgical steps during TKP vitrectomy |
|
||
Procedure |
Comment |
Surgeona |
|
Removal of |
The sutures are cut, the AC is rechecked for depth, |
AS or PS |
|
the TKP and |
fresh bleeding, fibrinous membranes, etc. An IOL |
|
|
completing |
may be implanted in those exceptional cases when |
|
|
reconstruction |
the retina was not detached and silicone oil is not |
|
|
of the anterior |
injected. If silicone oil is used, the viscoelastics should |
|
|
segment |
be either left behind7 or replaced with air, not BSS.8 |
|
|
|
The iris diaphragm should be reconstituted if the |
|
|
|
pupil is mydriatic and sufficient amount of the iris is |
|
|
|
left. If the iris needs to be sutured, the pupil must not |
|
|
|
be made too small so that it does not interfere with |
|
|
|
postoperative inspection of the retina or hinder any |
|
|
|
future posterior segment surgery |
|
|
Grafting |
The standard PK rules are followed. The graft diameter |
AS |
|
|
should be 0.5 or 0.75 mm larger than the trephined |
|
|
|
button’s diameter |
|
|
Final check on |
To determine whether any additional manipulation |
PS or AS |
|
the posterior |
needs to be made (e.g., adjusting the silicone oil level, |
|
|
segment |
removal of fresh hemorrhage) |
|
|
Closure of the |
The infusion cannula is finally removed and all scle- |
PS |
|
sclerotomies |
rotomies are closed |
|
|
Removal of the |
Alternatively, this may precede the closure of the |
PS or AS |
|
Flieringa ring |
sclerotomies |
|
|
7 In which the IOP must be very closely monitored during the first few postoperative days
8 If air is left in the AC in an aphakic eye with silicone oil implantation, the patient should not be in a face-down position for a few days to prevent silicone oil prolapse.
414 Ferenc Kuhn, Robert Morris, C. Douglas Witherspoon
2.15.3.1.3 Outcomes
With regard to outcome:
•In the vast majority of the cases, the donor cornea is not rejected and remains clear. In one large study with long-term follow-up, the graft remained clear at 1 year in 65% of eyes [7]. Another large study with an average follow-up of 25 months showed that the retina was attached and the graft remained clear in 73% of eyes.
•Postoperative graft failure may or may not be caused by the fact that the transplantation was done on an acutely injured eye, but the potential risk of graft failure must not serve as a justification for not performing timely TKP vitrectomy.
•Risks for graft failure include silicone oil implantation, multiple surgeries, and retinal detachment [7]. The TKP vitrectomy offers reasonable hope to achieve functional improvement for eyes with NLP vision [4, 12] or endophthalmitis [9].
2.15.3.1.4Eyes with Irreparable Anterior segment Damage
The TKP is useful in eyes with combined anteriorand posterior segment trauma to allow vitreoretinal surgery to be performed in a timely manner. If the cornea does not to remain clear because of major anterior segment ischemia, a permanent keratoprosthesis can be implanted instead of repeated PK procedures.
Permanent keratoprostheses (see Chap. 3.1) are well tolerated long term, offering vision in otherwise hopeless situations; the device even allows carrying out subsequent vitrectomy procedures [2, 6, 11]. It is crucial, however, to perform the initial TKP vitrectomy early, before the retina suffers irreversible damage.
Careful anterior segment reconstruction, however, may alleviate the need for PK or the permanent keratoprosthesis (Fig. 2.5.4).
DO:
•carefully consider whether EAV or TKP vitrectomy is more beneficial for eyes with severe combined anterior and posterior segment trauma; if the corneal opacity is not likely to resolve within a few weeks or months, perform TKP vitrectomy
•do meticulous surgery based on a well-designed plan; this is especially important if two surgeons operate and it is questionable which surgeon should perform which maneuvers and at what time during the operation
•try to accomplish all surgical goals in a single operation; conditions may be unfavorable for another major procedure in the next few days or weeks
DON’T:
•delay vitrectomy or perform suboptimal vitrectomy because of reduced corneal clarity; the window of opportunity to address a serious retinal condition is very narrow
•use too small a graft; if regrafting is necessary, the new button should be smaller than the previous one
Summary
Severe posterior segment trauma and a coexisting corneal injury incompatible with intraoperative visualization of the retina should not serve as justification for abandoning the eye. Both EAV and TKP vitrectomy
offer surgery without dangerous compromise on timing or completeness. The TKP allows virtually instantaneous visual rehabilitation due to corneal grafting.
References
[1]Eckardt C (1987) A new temporary keratoprosthesis for pars plana vitrectomy. Retina 7: 34−37
[2]Jahne MG (2000) 25 years Cardona keratoprosthesis after severe chemical eye burns: long-term outcome of 4 eyes. Klin Monatsbl Augenheilkd 216: 191−196
[3]Langefeld S, Kompa S, Redbrake C, Brenman K, Kirchhof B, Schrage NF (2000) Aachen keratoprosthesis as temporary implant for combined vitreoretinal surgery
416 Ferenc Kuhn, Robert Morris, C. Douglas Witherspoon
and keratoplasty: report on 10 clinical applications. Graefe’s Arch Clin Exp Ophthalmol 238: 722−726
[4]Morris R, Kuhn F, Witherspoon CD (1998) Management of the recently injured eye with no light perception vision. In: Alfaro V, Liggett P (eds) Vitrectomy in the management of the injured globe. Lippincott Raven, Philadelphia, pp 113−125
[5]Park S, Marcus D, Duker J, Pesavento R, Topping P, Frederick A, D’Amico D (1995) Posterior segment complications after vitrectomy for macular hole. Ophthalmology 102: 775−781
[6]Ray S, Khan BF, Dohlman CH, D’Amico DJ (2002) Management of vitreoretinal complications in eyes with permanent keratoprosthesis. Arch Ophthalmol 120: 559−566
[7]Roter S, Szurman P, Hermes S, Thumann G, Bartz-Schmidt K, Kirchhof B (2003) Outcome of combined penetrating keratoplasty with vitreoretinal surgery for management of severe ocular injuries. Retina 23: 48−56
[8]Smith RJ, Bhavsar AR (1998) Simplified technique for suturing a temporary keratoprosthesis for pars plana vitrectomy. Am J Ophthalmol 125: 251−252
[9]Steiner M, Steinhorst UH, Winter R (1996) Temporary keratoprosthesis, vitrectomy and autokeratoplasty in endophthalmitis treatment. Ophthalmologe 93: 729−731 [in German]
[10]Toth CA, Landers MB III (1993) A new wide-field temporary keratoprosthesis. Retina 13: 353−355
[11]Fischern T von, Langefeld S, Yuan L, Volcker N, Reim M, Kirchhof B, Schrage NF (1998) Development of a surface modified silicone-keratoprosthesis with scleral fixation. Acta Chir Hung 37: 219−225
[12]Yan H, Cui J, Zhang J, Chen S, Xu Y (2006) Penetrating keratoplasty combined with vitreoretinal surgery for severe ocular injury with blood-stained cornea and no light perception. Ophthalmologica 220: 186−189
2.16 Ocular Trauma in Children
and in Elderly Patients
Ferenc Kuhn
2.16.1Introduction
Injuries occurring to children and elderly people have some unique features that deserve special attention. A brief overview of these distinctive features are provided below; otherwise, see the relevant chapters for more information.
2.16.2Pediatric Injuries
2.16.2.1General
•The younger the child, the more different the injury’s characteristics are from those occurring in the adult population. This is compounded by the eye’s different anatomy (see Sect. 2.16.2.6.1).
Children are at a higher risk of an eye injury than adults due to:
•Immature motor skills, paired with a tendency to imitate adult behavior
•Reduced “common sense” control over behavior and emotions
•Strong motivation from peer pressure and natural curiosity to “just do it”
In this chapter, children are defined as those under 19 and elderly as those 60 years of age or older.
The author is greatly indebted to JM Rohrbach, Tübingen, Germany for his invaluable contributions to this chapter.
418 Ferenc Kuhn
•Increased levels of male hormones in adolescent boys.
•The child usually has a long life expectancy; permanent visual loss therefore represents a greater burden for individual, family, and society.
•Amblyopia is a major concern in the appropriate age group; every effort should be made to restore the normal anatomy and the eye’s refractive power as early as possible, and to instigate anti-amblyopia (orthoptic) treatment as necessary. The threat of amblyopia is somewhat smaller in children who are myopic since they have relatively preserved near vision.
•Posttraumatic stress disorder is common in children and may require professional help to treat [50].
2.16.2.2 History
With regard to history:
•Wearing a white coat during the examination may be frightful to the child; wearing “civilian” clothes is recommended instead.
•Explaining what is going to happen and that the examination will be painless is much more important in children than in adults.
•The child may refuse to cooperate with the ophthalmologist’s efforts to elicit exactly how the injury occurred. The child may be afraid of the parent’s retribution (e.g., because abuse has occurred; see Chap. 3.3) or of punishment for an illegal activity . To escape responsibility or accountability, the child may give no information, false information, or even fabricated information [40]. The reliability of history is greatly enhanced if a witness can be identified.
•Injuries that rarely occur in adults, such as an animal bite to the face and eyes (Fig. 1.1.5), are much more common in children. Such injuries have systemic implications, which must not be neglected.
Typically, under 7 years.
Throughout this chapter, the “parent” may be a legal guardian or a caretaker.
i.e., fighting with a sibling.
Unless, of course, the witness is the adult responsible for the injury.
e.g., tetanus or rabies prophylaxis.
2.16 Ocular Trauma in Children and Elderly Patients |
419 |
2.16.2.3 Epidemiology and Prevention
With regard to epidemiology and prevention:
•Children suffer 27−52% of all ocular trauma [18, 26, 39], a disproportionate rate. One-quarter of open globe injuries occurred in children in one study [16].
•Up to a third of persons hospitalized for trauma in the U.S. are children [30, 46, 59], with a hospitalization rate of 9 per 100,000 persons per year among those aged 20 years or less [8].
•Injury is the leading cause of monocular blindness in children [28].
•In a population-based report from the U.S., the estimated incidence rate of ocular trauma for those under 16 years of age was 15 per 100,000 persons per year [53].
•The risk of eye injury is measurably increased for children from a socioeconomically challenged population [13].
•Injuries to children (and to the elderly) are especially common at the home (39% and 59% in the USEIR, respectively). In one study, 15 cases of eye injury caused by pointed door handles were treated at a single facility over a 2-year period [10]. The trauma was very severe: the rate of optic nerve evulsion reached 93%.
•In developing countries, children are disproportionally represented among those injured. An unpublished study from Mali found that 40% of all eye injury cases involved children. The most common activity was play.10 One-third of the injured children did not arrive at the ER within 24 h.
•Needle injury is surprisingly frequent among children: in one study 1% of all pediatric cataracts undergoing surgery were caused by a needle [42]. Of the 42 eyes, 29% developed endophthalmitis; the rate reached 50% if the object was a hypodermic needle.
The data are from the USEIR unless otherwise indicated.
KF Sylla, Bamako, Mali
10 Included using sharp needles that women use to plait their hair.