Test ID 4993 Electron Microscopy
Useful For
Identifying tumor
Diagnosing medical disorders such as storage diseases, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and primary ciliary dyskinesia
Testing Algorithm
For nontumorous renal specimens, see 70064 / Renal Pathology Consultation, Wet Tissue for Electron Microscopy.
For platelet disorders, see PTEM / Platelet Transmission Electron Microscopic Study.
For muscle specimens, see MPCT / Muscle Pathology Consultation.
For CADASIL genetic mutation testing on blood, contact Mayo Medical Laboratories.
Special Instructions
Method Name
Electron Microscopy
Reporting Name
Electron MicroscopySpecimen Type
VariesTissue source required for testing to be performed.
Forms:
1. Electron Microscopy Patient Information in Special Instructions
2. Electron Microscopy Procedures of Handling Specimens for Electron Microscopy in Special Instructions
3. If not ordering electronically, complete, print, and send a Pathology Test Request Form (T246) with the specimen (http://www.mayomedicallaboratories.com/it-mmfiles/pathology-request-form.pdf).
A completed Patient Information Sheet is required for all Electron Microscopy Consultations (see Special Instructions)
Collect specimen according to the instructions in Electron Microscopy Procedures of Handling Specimens for Electron Microscopy in Special Instructions. Do not place on ice, dry ice, or freeze.
Submit only 1 of the following specimen types:
Specimen Type: Fixed wet tissue
Container/Tube: Electron Microscopy Kit (Supply T660) or leak-proof container
Specimen Volume: Entire specimen
Additional Information: 70012 / Pathology Consultation may be added if deemed necessary by the reviewing pathologist.
Specimen Type: Whole blood (Neuronal Ceroid Lipofuscinosis-NCL only)
Container/Tube: Electron Microscopy Kit (Supply T660), green top (sodium heparin), or yellow top (ACD [solution B])
Specimen Volume: 5 mL
Collection Instructions: Do not transfer blood to other containers.
Additional Information: Specimen must arrive within 48 hours of draw.
Specimen Minimum Volume
Varies
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Varies | Ambient (preferred) | |
Refrigerated |
Clinical Information
Crucial diagnostic information for the study of human disease may be provided by transmission and scanning electron microscopy. Often information of a confirmatory nature or of educational value to the clinician and pathologist can be obtained by this procedure.
In recent years, the technology involved in electron microscopy has progressed to the point where methods have become standardized and the instrumentation routine. The electron microscope is a fundamental tool in medical diagnostic and cellular pathobiological investigations, because it is at this instrument's level of resolution that most structural correlations with function and metabolism are visible.
Reference Values
An interpretive report will be provided.
Cautions
Certain factors are necessary for interpretation of electron microscopic images as follows:
-Optimal fixation of viable and representative tissue is imperative.
-Tumor biopsies must be accompanied by a history, hematoxylin and eosin-stained slides, and a paraffin block.
-The tissue submitted must have been viable at the time of fixation.
-Selection of tissue representative of the lesion is essential.
Day(s) Performed
Monday through Friday; Varies
Report Available
4 daysPerforming Laboratory

Test Classification
This test uses a standard method. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
88348