Visualization of the basement membrane zone of the bladder by optical coherence tomography: feasibility of noninvasive evaluation of tumor invasion.
OBJECTIVE
Imaging techniques with high resolution are evolving rapidly for medical applications and may substitute invasive diagnostic techniques. The use of ultrahigh resolution optical coherence tomography (UHR-OCT) to image healthy and morphologically altered bladder tissue with virtual histology is evaluated ex vivo to define parameters necessary for future, diagnostically relevant in vivo systems. Here, special focus is on the visualization of the basement membrane zone.


METHODS
Optical coherence tomography examinations were performed by using a modified commercial OCT system comprising a Ti:sapphire femtosecond laser to support an enhanced resolution of 3 microm axial x 10 microm lateral. Tomograms of 142 fresh human bladder tissue samples from cystectomies, radical prostatectomies, and transurethral tumor resections were recorded and referenced to histologic sections using standard hematoxylin and eosin staining.


RESULTS
OCT of normal bladder mucosa allows for a clear differentiation of urothelium and lamina propria. The basement membrane zone is identified as a narrow, low-scattering band between these layers. This allows for reliable exclusion of invasion. Healthy urothelial tissue, carcinoma in situ, and transitional cell carcinoma can be differentiated using this imaging technique. Sensitivity of UHR-OCT for malignant bladder tissue could be determined to be 83.8%, and specificity to be 78.1%.


CONCLUSIONS
UHR-OCT is considered promising in the attempt to strive for fluorescence cystoscopy-guided virtual histology as a means of supporting therapeutic decisions for bladder neoplasia.
Hermes
Barbara
B
Institute of Pathology, University Hospital RWTH Aachen, Aachen, Germany.
Spöler
Felix
F
Naami
Amjad
A
Bornemann
Jörg
J
Först
Michael
M
Grosse
Joachim
J
Jakse
Gerhard
G
Knüchel
Ruth
R
D000537:Aluminum Oxide; D001485:Basement Membrane / Q000473:pathology*; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000473:pathology; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007834:Lasers; D009092:Mucous Membrane / Q000473:pathology; D009361:Neoplasm Invasiveness; D012680:Sensitivity and Specificity; D014025:Titanium; D041623:Tomography, Optical Coherence / Q000379:methods*; D001743:Urinary Bladder / Q000473:pathology*; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000473:pathology; D019459:Urothelium / Q000378:metabolism / Q000473:pathology
D014025:Titanium; D000537:Aluminum Oxide