The mLCI imaging modality is based on an interferometric optical sectioning technique similar to that used in Fourier-domain optical coherence tomography.22 mLCI measures depth-resolved reflectance profiles of a sample A-scan analogous to the acoustic reflection profiles commonly seen in ultrasound. It applies broadband light from a superluminescent diode (SLD, Superlum Diodes) with a bandwidth of 54.2 nm and a center wavelength of 837.5 nm. This provides a coherence length, or axial resolution, of 5.7 μm, enabling high-resolution measurements of thickness. The light from the SLD is split into eight channels (six are used) and six fiber optic couplers (AC Photonics). Each creates six parallel sample and reference arms for each interferometer. The parallel interferometers contain electromechanical fiber optic shutters to allow gating of each reference arm, for background subtraction during measurement. In the sample arms of the device, the six fiber optic cables are routed through a polyetheretherketone (PEEK, ZEUS, Inc.) sheath and into the common endoscopic probe, as shown in Fig. 1. A custom-imaging module was built and mounted to the distal end of the endoscope, leading the fluorescence measurement field by 20 mm and rotated 180 degrees. This imaging module acts to hold the fibers securely in place and enables imaging of six measurement spots on the surface of the vaginal epithelium through the polycarbonate tube.19,21 The light returned by the sample is recombined with the reference light by the aforementioned fiber optic couplers, and detected with a multichannel spectrometer (Avantes, Inc.). The spectrometer allows simultaneous detection of all six interference signals and operates at a rate of .19 Data are transferred via a USB 2.0 interface to a laptop computer, which provides automated control of the fiber optic switches for background subtraction and preliminary data analysis. The background-subtracted interference spectra are then converted from wavelength to wavenumber, resampled to restore linearity, and Fourier transformed to reveal A-scans, or depth scans, for the measurement position.19 A linear and rotational positional encoder system relays the axial and azimuthal coordinates of the endoscope to both systems, to enable co-registration between the two modalities.