Ординатура / Офтальмология / Английские материалы / Strabismus Surgery and Its Complications_Coats, Olitsky_2007

This chapter will discuss the general medicolegal aspects involved in the care of the strabismus surgery patient. The goal of this discussion is to provide the strabismus surgeon a basic understanding of the medicolegal duties and implications involved in the surgical care of the strabismus patient. While some aspects of this discussion are pertinent to the general care of any medical patient, it is not the goal of this chapter to provide a detailed overview of this subject. Furthermore, this chapter should not be thought of as a legal reference with regard to this subject matter. More detailed information regarding this subject may be found in legal textbooks [1].

32.1 Informed Consent

Initiation of a surgical procedure usually involves providing and obtaining informed consent from the patient or legal guardian. Informed consent is a legal concept. It provides that a patient has the right to know and understand the potential risks, benefits, and alternatives to a proposed surgical procedure. A patient’s consent is based on information that a reasonable healthcare provider would give to a reasonable patient under the same or similar circumstances in a similar practice of medicine. The basis of informed consent is that the physician has an obligation to disclose to his/her patient sufficient information that will allow the patient to evaluate a proposed surgical procedure before agreeing to submit to it. Based upon this, informed consent requires that a patient has an understanding of that procedure for which he or she has consented. A patient who authorizes a procedure but does not understand what he or she has consented to has not been given effective informed consent. It should be noted, however, that while a patient may understand at the time consent is given, it is not uncommon for patients to later forget what they have learned during the consent process.

It is of paramount importance in the informed consent process that the patient adequately understands the risks, benefits, and alternatives to the procedure being proposed. The surgeon should disclose any and all risks that a reasonable person would consider important in order to decide whether or not to undergo the treatment suggested. The surgeon does not need to disclose every conceivable risk, but must discuss those risks

that a reasonable patient would expect to be informed about in order to make an adequately informed decision. In some states, law has codified specific risks of a given procedure that must be disclosed. When attempting to decide if a patient has been given adequate preoperative information, the courts generally utilize “objective” or “subjective” tests to determine if the patient would have refused treatment had the physician provided adequate information. Using an “objective test,” the plaintiff would need to prove that a reasonable person would not have undergone the procedure if he or she had been properly informed. The “subjective test” examines whether the specific “individual patient” would have chosen to proceed with the proposed procedure if given full information. In most cases the objective standard is used and it generally protects the physician from the testimony of a patient who may claim that he/she would not have consented to the procedure if fully informed of the risks by the surgeon solely to win an award. The scope of the surgeon’s duty to disclose the known risks of a procedure are measured against a reasonable medical practitioner in the same field of medicine and what he/she would have disclosed under the same or similar circumstances. Because the reasonable medical practitioner only exists in theory, the plaintiff must generally establish this standard through the use of an expert medical witness at the time of a trial.

32.2 Written Consent

A written consent provides proof of a patient’s desire to proceed with a planned surgical procedure. Because the written consent is meant to provide evidence of proper informed consent, it should be incorporated into the medical record. Properly documented informed consent should include all of the elements shown in the Table 32.1.

Often the surgical consent is worded in fairly general terms and should include language that a layperson can understand. It may not specifically outline in writing each of the abovementioned details. If these specific elements are not documented in the written surgical consent itself, we recommend documenting them and/or the fact that they were discussed in the office and/or hospital medical record. The general surgical consent form will document the patient’s desire to proceed

Identification of the disorder being treated

Disclosure of the surgical procedure to which the patient is consenting

Relevant risks and possible adverse consequences of the surgical procedure

An indication that the patient understands

the nature of the proposed treatment and the alternatives

with a planned surgical procedure based upon an informed consent. The medical record will allow specific documentation regarding each of the elements of the informed consent that was given and obtained. The risks of a specific surgical procedure may be applicable only to the individual strabismus surgery being performed. However, some general risks inherent to many strabismus surgical procedures may be appropriate for documentation in the medical record. In general, we discuss the risk of underand overcorrection, the possible need for additional treatments and/or strabismus surgery, uncorrectable diplopia, infection, loss of vision, loss of the eye, and possible anesthetic complications which may include death. Likewise, general alternatives should also be discussed. Most commonly these alternatives include observation alone in appropriate cases, prism glasses if the deviation is small, and occlusion of one eye to avoid diplopia. In selected cases, consideration of botulinum toxin injection, orthoptic exercises, patching and glasses may be included as alternatives. Each of these alternatives may have its own specific advantages and risks of potential undesirable outcomes as well. We like to think of this process as documenting a request for surgery rather than consent for a surgical procedure. In other words, it should be clear from the medical documentation that the patient or parent is requesting a surgical procedure after discussing the risks, alternatives and benefits of that specific procedure and not simply consenting to the procedure as a suggestion given to them by the surgeon.

Under most circumstances, and almost universally true regarding strabismus surgery, consent of the patient is required before treatment. When the patient is legally incompetent to provide consent, the consent must be obtained from a person who is empowered to consent on the patient’s behalf. The majority of strabismus procedures are performed on children. In general, children (minors) are not considered legally competent to provide consent. Consent must be obtained from the child’s parent or legal guardian. In some circumstances a minor may provide for their own consent. These situations may include cases where the minor is married or otherwise emancipated. Specific rules in this regard vary from state to state. When a question arises regarding the competency of a patient who needs surgery, or if there is uncertainty regarding the person who may legally provide consent, it may be best to discuss the situation with an attorney.

32.3 Medical Malpractice

is a civil or personal wrongdoing. A wrongdoing can be intentional and due to negligence. For wrongdoing to be considered intentional, it must not only be committed intenbut the person performing the act must realize to some that harm could result. An intentional wrongdoing also violates another person’s interest. A negligent wrongdoes not require that an act is committed. A wrongdoing include failure to act when the person, in the case of medi-

cal malpractice a physician, had a duty to act.

32.4 Intentional Torts

32.4.1 Battery

Battery is the intentional touching of another person in an impermissible manner, without the person’s consent. Battery is an intentional act that violates the physical security of another person. It may occur even if the receiver of the battery is not aware that the offense has been committed. Battery may occur when a wrong-site surgery takes place or when a surgical procedure is performed in the absence of a properly obtained surgical consent. Other egregious examples of battery might include imprinting the initials of the surgeon in the retina with a laser or otherwise engaging in improper conduct during surgery.

32.5 Unintentional Torts

Negligence is an unintentional wrongdoing. It consists of an unintentional commission or omission of an act that a reasonable person would have done or not done under the same or similar circumstance. Surgical negligence consisting of a commission of an act might include performing a surgical procedure without a patient’s consent, or performing a procedure on the wrong patient or on the wrong body part. These acts would also be considered battery. Negligence is conduct caused by carelessness, which departs from a standard of care. Surgical malpractice may occur when a professional performing surgery commits an act of negligence. The forms of negligence include:

Malfeasance: execution of an unlawful or improper act

Misfeasance: improper performance of an act

Nonfeasance: failure to act when there is a duty to act.

There are two degrees of negligence:

Ordinary negligence: failure to do what a reasonable person would or would not do

Gross negligence: intentional omission of care that would have been proper to provide.

32.5.1 Elements of Negligence

In order for negligence to exist, the following four elements must be present: (1) duty to care, (2) breach of duty, (3) injury,

(4) causation. All four elements must be present in order for a patient to recover damages suffered as a consequence of a negligent act. Duty to care requires the existence of a relationship between the surgeon and patient. A duty exists based in part on the request for surgery form (consent form) reviewed and signed between the patient and operating surgeon prior to surgery.

The duty to care exists not only as a responsibility to provide care but also to provide care in an acceptable manner. This is often defined as the standard of care. In recent rulings, the courts have been less likely to rely on a community standard and more likely to apply a national standard when making a determination about the standard of care. For a breach of duty to exist, there must be a deviation from the standard of care. An expert witness generally provides interpretation of the standard of care at the time of trial. An injury must take place for a defendant surgeon to be considered liable. A surgeon may be negligent but may not be held responsible for damages if an injury does not occur. However, the definition of injury is not limited to a physical harm. It may also include loss of income or reputation as well as compensation for emotional distress, pain, and suffering. Likewise, the occurrence of an injury does not itself establish the presence of negligence. Harm or injury may occur secondary to an unavoidable complication, which did not represent a deviation from the standard of care. Finally, the fourth element necessary to establish a case of negligence requires that there is a causal connection between the surgeon’s negligent action and the resulting damages suffered by the patient.

32.6 The Medical Record

The medical record provides an archive of information if a question arises regarding the medical care provided to a patient. For this reason, it is important to document the basic content of both the examinations and the discussions that take place between the physician and patient. It should be recognized, however, that the medical record only represents a thumbnail sketch of examination findings, discussions, and recommendations. Its primary purpose is to support ongoing care of the patient and to act as a mechanism of communication to other physicians and medical personnel. While tampering with a medical record may send a wrong signal to a jury,

it is permissible to alter a medical record when new information is obtained or if a mistake made in an earlier patient encounter is recognized. If a circumstance occurs where a change or addendum is needed in the medical record, the existing note should not be destroyed or erased. A single line should be drawn through the statement(s) needing to be changed so that the prior information is still legible. A new statement should then be entered. Optimally, the change should be dated and signed/initialed by the person making the change. In an electronic medical record environment, these elements are generally automated and while a record can be amended, it is generally not possible to remove information from the record once the record has been electronically signed. It should be remembered that it is often easier to explain why a detail may have been left out of the medical record erroneously than to add or alter information once its absence is considered potentially damaging.

32.7 The Unhappy Patient

Even the most experienced and most thoughtful strabismus surgeon will eventually encounter a patient who is unhappy with his/her services. An occasional patient may even threaten legal action. Often the source of unhappiness is an unexpected or undesirable surgical outcome. Preoperative planning and discussions with the patient can help to reduce the risk of an unwanted outcome and can help to reduce the patient’s distress when an unwanted outcome occurs. Surprise over a bad outcome may be more likely to be associated with a decision to pursue medicolegal action than is the bad outcome itself [2]. It has been our experience that most patients who experience an undesirable outcome or adverse event appreciate a surgeon who is both sympathetic and honest with them. They also recognize when someone has tried their best to correct the problem, even if this means referring the patient to another doctor who may have more experience in dealing with the problem. In contrast, if the patient perceives their surgeon to be uninterested, uncaring, defensive and/or dishonest, they are much less likely to be tolerant of an unwanted outcome.

References

1.Pozgar G (2004) Legal aspects of health care administration, 9th edn. Jones and Bartlett, Boston, Mass.

2.Bettman J (1990) Seven hundred medicolegal cases in ophthalmology.. Ophthalmology 97:1379–1384

A

A-pattern, offsetting horizontal rectus muscles for  96

Aberrant regeneration of oculomotor nerve, surgical considerations  261–262

Abscess; subconjunctival  197, 230

– treatment of  230

AC/A ratio, high, treatment of with posterior fixation sutures  156–157

Access,surgical and palpebral fissures  1 Accessory Muscle  273–274 Accommodative esotropia

–bifocals and  166

–optical treatment of  165

–surgical indications  165

Accommodative esotropia, bifocals and  166 Accommodative paralysis; after inferior oblique surgery  200 Actions of the extraocular muscles  24–26

–cinch knot technique  145

–general principles  141–142

–in children  141, 145

–indications  141

–lower eyelid retractors  260–261

–ripcord technique  145–149

– surgical modifications to facilitate  141

–timing of adjustment  141

–traction knot technique  145 Advancement of the eyelids after vertical rectus

resection  259 Agyrosis  200 Amyloidosis  198, 282 Anesthesia

–general anesthesia  48

– general anesthesia; induction of  48

–Intraoperative awareness  287

–preoperative medications  48

–retrobulbar and peribulbar  49

–sub-Tenon’s infusion  49

–topical  49

–topical, complications of  288

– topical; modification of surgical technique  50 Anesthesia awareness, unintentional  287 Aniseikonia, as cause of diplopia  293, 301

Anomalous head posture. see compensatory head posture Anomalous retinal correspondence  302

Anterior ciliary arteries  15

Anterior oblique anterior transposition procedure

–indications  113–114

–techniques  114–115

Anterior segment; blood supply  203–204

–botulinum, role of  206–207

–classification of  205

–clinical presentation  205

– development of collateral blood flow  204

–incidence  204

–prevention of  206–209

–risk factors  204–205

–staging of surgery  209

Awareness during anesthesia, unintentional  287 Axes of rotation  21–22

Axial length, impact on surgery  88

– overview of strabismus treatment success  161–162

–treatment of nystagmus  162–163 Brown syndrome

–acquired  280

Concurrent strabismus and non-strabismus surgery  231 Concurrent systemic illness at time of strabismus

–anatomy of  7

–button holes  198

–histology  7

–incision options  72–74

–landmarks, surgical  16, 67

–plica semilunaris conjunctiva  7

–structure  7

surgery  188

Corneal topography; changes after strabismus surgery  296 Corneal ulcer  186–188, 230

–and muscle complications  194

–etiology  194

–prevention  194–195

–treatment of  197

Cyst; sudoriferous  196

D

Dellen, corneal  185–186 Dellen, scleral  200–201

Denervation and extirpation of inferior oblique  113 Diagnostic positions of gaze  24

Diplopia, at risk patients  304

–closed head injury  304

–incomitant strabismus  304–305

–previous anti-suppression therapy  305

Dissociated strabismus and inferior oblique overaction,

Duction limitation, in infantile esotropia  176 Duction limitation, postoperative  291–292 Duction movements  22

– swan incision  84–85

Indications for strabismus treatment  32

–asthenopia  28

–asymptomatic patients  29

–compensatory head posture  29–30

–diplopia  28

–incomitant deviation  28

–miscellaneous  30

–nystagmus  30

–psychosocial considerations  31–32

–eyelid changes following  264

–Technique  113–115

Inferior oblique inclusion syndrome  255

Inferior oblique muscle

–actions of  25–26

–double – bellied  272

–surgical anatomy  18–19

–traction testing  71

Inferior oblique muscle, surgery on

– advancement of  116

– anterior and nasal transposition  115

–anterior transposition  113–115

–denervation and extirpation  113

–disinsertion  111

–dissection of fascia  107

–general principles   105

–graded recession  109

–inclusion syndrome  255–256

–isolating muscle  106–107

–mydriasys and paralysis of accommodation, post operative  200

–myectomy  112

–nasal myotomy  115

–recession  109

Inferior oblique muscle overaction, surgery for  108–115 Inferior oblique myotomy  112

Inferior rectus muscle

–actions of  24–25

–surgical anatomy  17 Informed consent  307

Infratarsal lower eyelid retractor lysis  261

Instruments; surgical

–Scobee muscle hook  62

–typical set up  58–60 Iris angiography  204

J

J-Deformity of rectus muscle  256 Jensen procedure  136–137

– Partial tendon transposition, of rectus muscles  136–138 Jensen procedure, vessel-sparing technique  137

K

Keratitis, filamentary  188

Knapp transportation procedure  136

L

Laboratory testing; pre anesthesia  47

Laser photocoagulation, after eye wall perforation  218 Lashes; isolation of  57

Lateral canthotomy technique  248 Lateral rectus muscle

–actions of  24–25

–surgical anatomy  16

Lid splitting procedure for surgical access to superior rectus  276

Lights on/off test for dragged-fovea diplopia syndrome  300–301

Limbal incisions

–advantages/disadvantages  79

–closure of  81, 190–191

–conjunctiva, recession of  82

– dissection of fascia  80

–locations of  80

–modified  82

–technique  80 Listing’s plane  21–22 Locking suture bites  238

Loss of vision. see Vision loss, as complication of surgery Lost rectus muscles

–classification of  233

– clinical presentation and diagnosis  238–239

–following non-strabismus surgery  238

–intraoperative loss  239–240

–Lost rectus muscles  241–242

–neuroimaging and  241–242

Measurement artifacts, during recession surgery

–prism position  177–178 Medial rectus muscle

–actions of  24, 25

–surgical anatomy  16 Medical record, the  309

Monocular diplopia, etiology  173

Muscle malposition after resection, correction of  101

Mydriasis, after inferior oblque surgery  200 Myectomy; inferior oblique  111–112

Myectomy of inferior oblique, Spontaneous reattachment after  109

Myopexy, retroequatorial  156

Myopia associated strabismus; etiology & treatment of  154–156, 280–281

Myotomy; inferior oblique  112

N

Nausea and vomiting; post operative  51, 286–287

Needles; surgical

–choice of  62–63

–design features  62–63

–ideal characteristics  62–63 Neglect, elements of  309 Neo-synephrine. see phenylephrine

Neuroimaging, and strabismus  11, 12, 241–242, 270

–prism therapy  168–169

–refractive correction  165–166 Nystagmus

–Anderson procedure  30

–four-muscle recession  30

–Kestenbaum procedure  30

O

Oblique muscle overaction, surgery for. see specific muscle Ocular respiratory reflex  53

Oculocardiac reflex

–adjustable sutures and  53

–neural pathway  52

–prevention  52

–risk factors  52

Oculomotor nerve, aberrant regeneration, surgical considerations  261

Oculomotor nerve, functions  15

Oculomotor nerve, neurovascular bundle  113, 115 Oculomotor nerve paralysis, surgery for

–periosteal flap procedure  151–152

–recession and periosteal fixation of lateral rectus to orbital

Operating room lay out  58

Orbital decompression; as treatment for retrobulbar hemorrhage  248

Orbital fat, relationship to posterior Tenon’s capsule  253 Orbital fractures, occult  279

Orthoptic therapy  167–168

Over correction, after surgery  161–162, 291–292 Overmunus lens therapy for exodeviations  166

P

Pain; post operative

–management of  53–54

–severity of  54 Palpebral fissures

–and surgical access  3

–down-slanting  4

–upslanting  4

Partial tendon transposition, of rectus muscles

– four-fifths transposition, vessel sparing  135

–Hummelsheim procedure  135

–Hummelsheim procedure, augmented  135–136 Perforation; scleral

–clinical evidence of  217–218

–cryotherapy, complications of  218

–definitions  211

–hemorrhage and  218–219

–incidence  211–212

–prevention  219–220

– prevention; special surgical techniques  214

–retinal detachement and  218

–risk factors  212, 214–216

–prevention of  189–190

–treatment of  190–191

Pole test, after hooking rectus muscle  76

Posterior fixation suture

–indications for  156

–mechanism of action  156

–scleral perforation and  216

–techniques  156–157

Posterior fixation sutures, using pulley fixation  216

Postoperative care considerations

–antibotic administration  43

–patient instructions; adult  45

–patient intructions; child  43

–timing of follow-up  43 Povidone-iodine preparation  57 Pre operative management errors

–paralytic strabismus; unrecognized  174

–prism use errors: see prisms, for measureing strabismus  177

–restriction; unrecognized  174

–torsion, unrecognize  175

–undetected prism  292–293

Preoperative patient preparation  57 Preparation for surgery  41–42 Preseptal cellulites  227–229, 265

Prism, spectacle induced in anisometropia, calculation of  293

Prism, spectacle induced measurement of  178–180 Prism; spectacle-induced  178–180

Prism; unrecognized in spectacles  180–182 Prisms, for measuring strabismus

–prism orientation errors  176 Prisms and anisometropia  293 Prism therapy

–calculating oblique prism  168–169

–prescription tips  169

Pseudo-strabismus

–pseudo-esotropia  5

–pseudo-exotropia  6

–pseudo-hypertropia  6 Pseudoduction deficits  176–177

Ptosis, postoperative, as complication of surgery  259–261, 263

Ptosis, post operative, related to corticosteroids use  263

–function of  11

–heterotopic and strabismus  272–273

–rectus muscle paths  10

–structure of  10–11

Pyogenic granuloma  193

R

Recession, inferior oblique  109

Recession, rectus muscle without scleral sutures  214 Recession; inferior oblique, graded recessions  109 Recession of superior oblique tendon  128 Recession of the conjunctiva  82

Recession surgery, rectus muscles

–general principles  87

–hang-back technique  92–95

–hemi-hang back technique  95–96

–techniques, standard  89–92

–without scleral sutures  214 Record keeping  309

Rectus muscle procedures

–free tenotomy  96

–marginal tenotomy/myotomy  153–154

–recession surgery  87–97

–resection surgery  99–102

–transposition procedures  131–138

–tucking procedures  102–103

Recuts muscles

–abnormal insertions  273–274

–actions  24

–anatomy of  12

– head or toe maneuver, to confirm surgical isolation of

–recession procedures  87–97

–resection procedures  99–103

–dual suture technique  101

–general principles  99

–resection clamp technique  102

–tucking procedures  102–103

Restrictive strabismus, undiagnosed preoperative  39

Retraction of the conjunctiva, after surgery  191 Retraction of upper eyelids after superior rectus

recession  259

Retrobulbar anesthesia, complications of  287–288 Retrobulbar hemorrhage  248

Retrobulbar hemorrhage, treatment of  248 Retroequatorial myopexy  156

S

Scarring between Tenon’s capsule and conjunctiva  256 Sclera, thin, suggested surgical modifications  282 Scleral buckle, strabismus following

–etiology  277–278

–hydrogel explants and  279

Silcone expander, for superior oblique tendon  127–128 Sixth cranial nerve. see abducens nerve

Skin preparation; pre operative  57 Slipped rectus muscles

–clinical presentation  233–235

–etiology  233

–neuroimaging appearance  234

–prevention of  237–238

–repair of  237

–signs of  235

–step test  235

Spiral of Tillaux  12

Split rectus muscle, inadvertent  76

Spring back test for lost and slipped muscles  71, 234–235 Staging of surgery, in patients at risk for anterior segment

ischemia  209

Step test for slipped muscles  235

Strabismus with nystagmus; treatment of  174

Sub-Tenon’s infusion of anesthetic  49

Sub-Tenon’s infusion of anesthetic, complications of  248

–posterior tenotomy/tenectomy  128–129

–recession  128

– silicone expander of superior oblique tendon  127–128

–tenectomy  126

–tenotomy  126

–tenotomy, guarded  126

–surgical anatomy  18

–tendon laxity  71

–traction testing of  69–72

Superior oblique muscle overaction, surgery for  124–129 Superior oblique tendon transposition  138–139 Superior rectus muscle;

–actions  24–25

–surgical anatomy  17–18

–surgical dose  37, 38

–torsional diplopia  39

– which eye to operate  36 Sutures

–absorable  63–64

–collagen  63–64

–ideal characteristics  63

–mono and multi-filament  63

–nonabsorbable  64

–synthetic  64

Swan incision  84–86

Systemic illness at time of strabismus surgery  230–231

T

Tenon’s capsule

–episcleral (sub-Tenon’s) space  9

–function  9–10

Tenon’s capsule, prolapse of, postoperative  193 Tenotomy, free, of rectus muscles  96 Tenotomy/tenectomy of superior oblique tendon  126 Tenotomy/tenectomy of superior oblique tendon,

guarded  126