Ординатура / Офтальмология / Английские материалы / Step by Step Reading Pentacam Topography (Basics and Case Study Series)_Sinjab_2010

c h a p t e r 4

Examining the

Patient

52 Step by Step Reading Pentacam Topography

In the next chapters the case study will be presented very simply without mentioning all the data of the patient. That is because this book concentrates on the topography readings, but in our practice we should take care of every tiny data we obtain from the patient in order to give the patient his best chance and avoid any undesired complications, which might be due to our ignorance. For this reason, I am presenting in Table 4.1 a suggested evaluation sheet. It must be the basic but not the full for evaluation, i.e. you may add on what you feel is necessary. The sheet includes demographic information, ocular and systemic history and full ocular examination as follows.

OCULAR HISTORY

A patient’s ocular history helps to identify any potential postoperative problems that may arise and allows for adjustment, postponement, or cancellation of the procedure in question if necessary. We have to put in mind that when the patient is mono-ocular, he is not a candidate for any refractive surgery.

Previous Trauma

•Identification of any trauma in the cornea or other component of the visual axis that may alter corneal wound healing or potential visual outcome.

•Determination of condition, location, duration, and method of treatment (if possible).

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Previous Ocular Surgery

The identification and evaluation of a patient’s previous ocular surgery status is critical to the success of subsequent refractive surgery. Several situations must be considered.

•Artificial alteration of the refractive index secondary to faulty assumptions or calculations based on the IOL, scleral buckle, or other retinal procedures.

•Increased risk of retinal complications after surgical intervention.

•Difficulty obtaining proper suction and resultant flap complications.

FAMILY HISTORY

A thorough family history may elucidate potential contraindications or concerns with refractive surgery and long-term visual prognosis. A positive history of any of the following warrants further careful ocular evaluation prior to surgical intervention:

•Glaucoma

•Past history of high intraocular pressure after topical steroid application

•Corneal dystrophy or degeneration

•Untreated retinal pathology (e.g. retinal holes, tears, or detachment).

MEDICAL HISTORY

The preoperative systemic history should include questions related to several diseases and conditions, including pregnancy and lactation that may affect a surgical candidate’s suitability for surgery. The medical history should also include the followings:

Examining the Patient 57

Ocular Diseases

Pre-surgical assessment of refractive surgery candidates may reveal a history of several ocular diseases that precludes surgery or poses increased risk of intraoperative or postoperative complications such as:

•Corneal dystrophy

•Cataracts

•Keratoconus

•Iritis (must rule out preoperatively if visually symptomatic)

•Herpetic infection

•Corneal bacterial infection

•Retinal disease

•Significant lagophthalmos.

Vascular Diseases

Any vascular disease that compromises a person’s ocular performance or health is a contraindication for refractive surgery. Some are listed here:

•Malignant hypertension

•The controlled diabetes mellitus is a relative contraindication, otherwise it is contraindicated.

•Clotting or other blood disorders

Collagen Vascular Diseases

The severity of collagen vascular disease determines whether it needs to be evaluated before refractive surgery. Most patients with collagen vascular disease have very mild symptoms and use very little medication. If a patient rheumatoid-factor is positive and has severe collagen

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vascular disease, refractive procedures are contraindicated. Examples of collagen vascular disease are listed here:

•Systemic lupus erythematous

•Rheumatoid arthritis

•Scleroderma

•Fibromyalgia.

Inflammatory Disorders

Inflammatory disorders, such as those listed below, should be controlled and stable prior to refractive surgery:

•Multiple sclerosis

•Hyperthyroidism

•Crohn’s disease.

Infectious Diseases

An active infectious disease is generally a contraindication for refractive surgery:

•Viral

•Bacterial

•Fungal.

MEDICATIONS AND ALLERGIES

Certain drug therapies may be contraindicated or alter postoperative outcome in patients undergoing refractive surgery. Allergies must also be considered. We should pay attention to such drugs:

•Isotretinoin (Accutane; Hoffmann-La Roche Inc., Nutley, N]) [contraindicated in potential photorefractive keratectomy (PRK) patients because of increased risk of PRK haze]