Term
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Definition
| one of the most useful and most commonly used diagnostic agents (stains) in ophthalmology and optometry |
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Term
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Definition
| a synthetic organic compound available as a dark orange/yellow water- soluble dibasic dye of xanthine series |
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Term
| Available Forms of Sodium Fluorescein |
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Definition
• Can be applied to eye
• Topically in form of solution
• By Fluorescein-impregnated filter paper strips • Injectable form for IV use |
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Term
| Assessment of Ocular Surface Integrity |
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Definition
w sodium fluorescein
• Frequently used to detect lesions of ocular surface owing to its high degree of ionization, it neither penetrates the intact corneal epithelium nor forms a firm bond with any vital tissue
• Instillation of dye in cul-de-sac allows determination of corneal and conjunctival lesions such as abrasions, ulcers, and edema, and aids in detection of foreign bodies
• Epithelial defect appears as vivid green fluorescence |
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Term
| How Does Staining Take Place? |
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Definition
-Any break in epithelium
-Penetration of Fluorescein in adjoining Bowman’s and stromal layer
-Dye makes contact with an alkaline interstitial fluid
-Fluid turns bright green owing to its PH indicator properties and depending on extent of lesion |
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Term
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Definition
| staining of corneal infiltrate |
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Term
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Definition
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Term
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Definition
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Term
| Intravenous Indication Fluorescein Angiography |
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Definition
• About 10 ml of a 5% solution injected in antecubital vein
• The dye normally appears in central retinal artery in
10–15 seconds
• Shows retinal blood vessels in high contrast
• Nonvascularized, pigmented retinal and subretinal lesions appear as dark areas against the green fluorescing background
• Proven helpful in diagnosis of a variety of pathological conditions of fundus, various macular lesions, choroidopathy, diabetic retinopathy, etc. |
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Term
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Definition
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Term
| Contamination of Fluorescein |
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Definition
-serious risk
• Even greater than that encountered with the majority of other eye drops
• As these individual drops are liable to become infected with bacteria and, at the same time, are frequently used on damaged tissue that is prone to infection, very great care must be taken in their use
• Pseudomonas aeruginosa—most dangerous microorganism with which fluorescein eye drops are inclined to become invaded
- Phenylmercuric acetate or nitrate 0.002%
• Best bactericide for preserving fluorescein drops, and this is effective
against Pseudomonas, given adequate contact time
- However, the safest method is sterile single-dose units or sterile fluorescein-impregnated paper strips; both are readily available and to be highly recommended |
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Term
| conclusion about fluroscein |
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Definition
• Fluorescein stain is a very useful diagnostic agent in ophthalmic clinical practice and has many applications.
• The use of diagnostic dyes represents one of the most efficient, objective, noninvasive, and directly visible means we have of identifying and tracking ocular structures at the cellular level.
• Every PA must understand the proper use of its clinical application, contraindication, and side effects in clinical use. |
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Term
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Definition
- 70% caused by viruses
• Accompany common cold (mild symptoms) • Adenoviruses, EBV, HSV, coxsackie A
- Bacterial
• Strep. pyogenes (Beta strep group A)
• Important to treat to prevent rheumatic fever
• Other causes less common
• Diagnosis—rapid strep test and throat culture • Newer test—PCR |
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Term
| Viral vs. Bacterial Pharyngitis |
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Definition
Strep- Marked pharyngeal pain/difficulty swallowing, High fever, Thick exudate covering tonsils and posterior pharynx, Lack of cough
Viral- Presents as part of clinical picture of common cold or flu, Low-grade fever, fatigue, myalgias, Exudate uncommon, May have cough as part of cold or flu |
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Term
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Definition
And you can see here in the top photo, these particular hemorrhaging and the redness, there's really no exudate there.
And look at all this white pus on these tonsils. That is a true-- and the swelling. That is a true bacterial pharyngitis. The top photo is, if I had to-- if that was my patient, I'd say you most likely have a viral pharyngitis.
But since we never really know for sure, we're going to do further testing. |
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Term
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Definition
• Member of herpes family
• Causes infectious mononucleosis
• Transmitted by salvia, incubation period 5–15 days
• Peak age 14–18
• Signs/symptoms
- Fever, pharyngitis, malaise, lymphadenopathy (posterior cervical), rash, splenomegaly
• Labs
- Atypical lymphocytes |
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Term
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Definition
• Use to detect IgM class heterophile antibody
• Antibodies detected can be caused by conditions other than IM (rare), such as:
• Hepatitis, rubella, leukemia, RA, lymphoma • Sensitivity is 85%, and specificity is 100% |
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Term
| EBV-associated antigens testing |
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Definition
- Viral capsid antigen
• IgM—appears early and disappears in 4–6 weeks • IgG—peaks in 2–4 weeks, declines slightly, but
persists for the rest of patient’s life
- EBV nuclear antigen
• Appears 2–4 months after onset of symptoms and persists for the rest of the patient’s life |
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Term
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Definition
Antibody
Time of Appearance
Persistence
% of IM Patients With Ab
VCA-IgM
At presentation
1–2 months
100%
VCA-IgG
At presentation
Lifelong
100%
EBNA
3–6 weeks
Lifelong
100%
VCA: viral capsid antigen
EBNA: Epstein-Barr nuclear antigen
VCA-IgM is the best indicator of primary infection. Presence of VCA-IgG and EBNA indicates past infection. |
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Term
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Definition
Local invasion—exotoxin release
-Pharyngitis—“strep throat”
• Risk of untreated patient—rheumatic fever
• Cannot diagnose with Gram stain!!!
-Scarlet fever—red rash from erythrogenic toxin
Characteristics
-Catalase negative, beta hemolytic
-Lancefield Group A cell wall antigen
-Never normal flora, always a pathogen
-Disease caused by
• Local invasion, exotoxin release
• Delayed antibody-mediated disease |
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Term
| Laryngotracheobronchitis (Croup) |
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Definition
- General
• Viral infection of the glottic and subglottic
region
- Epidemiology
• Disease of childhood ages7–36months • Very few cases over age 6
- Etiology
• Parainfluenza virus most common
- Clinical findings
• Inspiratory stridor, barking cough
• Retractions
- Laboratory findings
• Neck X-ray(typically not needed) • Steeple sign • Differentiate from epiglottitis with lateral X-ray |
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Term
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Definition
• Generally due to
H. influenzae (type B)
• Culture by direct swab
• Acute epiglottitis is an emergency due to difficulty breathing— intubate and treat with antibiotics
• Development of HiB vaccine has drastically reduced cases |
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Term
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Definition
| Laryngotracheobronchitis (Croup) |
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Term
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Definition
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Term
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Definition
• Usually occurs in setting of viral URI
• Common causes are Strep. pneumoniae and
H. influenzae (not type B)
• Specimen collection by direct sinus sampling or
nasal culture of sinus ostium
• Usually treated empirically, although plain radiographs of the sinuses may show opacification, air-fluid levels, or mucosal thickening of >4 mm. |
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Term
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Definition
• A: AIR-FILLED SPACES • SINUSES
• B: BONES
• FRACTURES, LYTIC LESIONS
• B: BLOOD
• SUBARACHNOID, SUBDURAL, EPIDURAL,
INTRAVENTRICULAR, INTRAPARENCHYMAL
• B: BRAIN
• INFARCTION, INFECTION, EDEMA, MASSES, SHIFT
• C: CSF SPACES
• ELEVATED ICP, ATROPHY, HYDROCEPHALUS, EDEMA |
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Term
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Definition
Normal air-filled spaces in brain window: A—maxillary sinuses
B—mastoid air cells
C—ethmoid sinuses
D—sphenoid sinuses E—frontal sinuses |
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Term
| Air-Filled Spaces Look for |
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Definition
• Air-fluid level
• May represent occult facial fracture
• Sinus mucosal thickening
• Polyps |
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Term
| Specialty Studies, CT face |
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Definition
• Thinner slices than head CT
• Get if concern for facial bone fractures
• Look for entrapment of extraocular muscles in orbit fracture |
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Term
| Specialty Studies, CT orbits |
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Definition
• Evaluation for foreign body
• Must have high index of suspicion if mechanism in place (i.e., hammering metal on metal) |
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