Diagnostic Techniques Flashcards
Objective
Information that can be measured or
perceived by the investigating clinician;
i.e. signs
e.g. temperature, size , color, duration,
consistency, surface contour, etc…
Subjective
Patient’s own interpretation of a clinical
circumstance; i.e., symptoms
Relies on neurologic and psychologic
experiences
e.g. patient awareness of presence of a
lesion, pain intensity, pain quality
(stabbing, burning, shocking, etc…),
temperature, etc…
Differential Diagnosis
* Orderly sequential approach
* Gathering and analyzing data
* Knowledge and experience enable
recognition of abnormal findings
* …
Include and/or exclude disease processes
based on an educated assessment of the
process
Gather and analyze data
– History
– Clinical findings
(2)
– Lab data
- Specific/unique signs
- Specific/unique symptoms
Differential Diagnosis
* Be aware of characteristic (2)
radiographic
appearances
clinical
manifestations
- Be aware of characteristic manifestations
(3)
– Age
– Gender
– location
Clinical Description
* single vs multiple, (aka systemic)
* location
* relative proximity to adjacent structures
* size in dimension (mm)
* outline - (2)
* color –(4)
* consistency – (3)
* intensity –(5)
* base and surface
well-demarcated vs diffuse
red, white, mixed, pigmented
firm, flaccid, compressible
mild, moderate, intense, striated, lacy
- surface – (5)
smooth, corrugated, eroded, raised,
depressed
- base – (4)
pedunculated, sessile, nodular, dome-shape
Diascopy
compressing tissue with a glass slide to
determine vascular nature of a lesion
Palpation
feel and press a lesion
to yield information
about texture,
consistency,
temperature and
function
Probing
- palpation with an
instrument - instruments include
perio probe, caries
explorer, needle tip, etc.
Percussion
- striking tissues with
fingers or an
instrument and
listening to resulting
pressure changes in
the tissues - eg. tooth ankylosis
Aspiration
- withdrawl of fluids
from a body cavity - E.g., needle aspiration
of cysts, vascular
tumors, purulent
swellings, etc
Auscultation
- listening for sounds
within the body
Diagnostic Lab Tests
for Oral Lesions
(3)
- Biopsy
- Immunofluorescence
- Exfoliative Cytology
- Biopsy -
(4)
Incisional
Excisional
Aspirational
Needle
I. BIOPSY INDICATIONS
(3)
- Lesion with > 14 day duration
- Unusual location
- Unusual appearance
Suspicion of neoplasia
(7)
– Induration
–Fixation
– Chronicity
– Lymphadenophathy
– Unexplained leukoplakia
–Persistent erythroplasia
–Persistent ulceration
III. BIOPSY INDICATIONS
* Any — tissue
* Confirm diagnosis of —
excised
systemic disease
Needle Biopsy
aka
(2)
Fine Needle Aspiration (FNA)
Fine Needle Aspiration and Cytology (FNAC)
Needle Biopsy
Indications
(3)
- To determine the cause of tissue
enlargement. - To distinguish between benign and
malignant processes. - To stage metastatic cancer
Needle Biopsy
Limitations
(3)
- More technique sensitive with
additional preservatives and lab
processing - does not localize cells to affected
tissues - appositional information to
adjacent tissues is lost
ORAL EXFOLIATIVE
CYTOLOGY
* Indications
(5)
– Innocuous lesion
–Suspicious lesion with negative biopsy
–Patient refuses biopsy
–Follow-up of treated malignancy
– Lesion where patient is a poor risk for
surgery
ORAL EXFOLIATIVE
CYTOLOGY
* Contraindications
(4)
– Keratotic or crusty mucosa
– Red, vesicular or velvety mucosa
– Submucosal swelling with normal mucosa
– Suspicion of malignancy
CULTURE AND SENSITIVITY
TESTING
* Indications
(3)
– Life threatening infection
– Unsuccessful previous antibiotic therapy
– Immunosuppressed patient
CULTURE AND SENSITIVITY
TESTING
* Limited use in dentistry
(2)
– Difficult for anaerobic conditions
–Turnover time too long; best to attempt
trial therapies of certain antibiotics as
results may occur quicker than the time
interval of the test
oral cancer screening aids
* Assist in the detection of…
* Non-invasively assesses the — of a mucosal abnormality
early potentially
malignant mucosal changes that are difficult to
discern by visual inspection alone
malignant
potential
Tissue Autofluorescence Imaging
* Increase the ability to distinguish the —
* High sensitivity but low specificity in
distinguishing (2)
* High sensitivity and specificity in identifying
areas of (2) that
extends beyond the clinically evident lesion
lesional mucosa and healthy mucosa
premalignant and chronic inflammatory lesions
dysplasia and invasive cancer
❑ Refractory index of tissue drives this
– We see
– Blue light of the scope =
– UV =
500-600 nm
400-460 nm
<400 nm
Many endogenous fluorescing products:
(7)
tryptophan, porphyrins, collagen, elastin,
flavins, NADH, fluorophores
Epithelial fluoresencing compounds:
– FAD (flavin adenine dinucleotide)
excites at — nm
– NADH (nicotinamide adenine dinucleotide)
excites at — nm
515
450
