Overview
The CytoCam-IDF microcirculation camera is the latest generation handheld video microscope for visualization of microcirculatory alterations, based on Incident Darkfield technology. The Cytocam-IDF imaging technique may be seen as the technological successor of the Sidestream Darkfield Imaging (SDF) technique, which has been used in more than 300 papers on microcirculatory measurements.
The Braedius CytoCam is a system for the real-time observation of the human microcirculation. The handheld video microscope platform supports the medical professional to better understand the microcirculatory condition caused by a disease as well as the effects and effectiveness of an applied therapy.
The CytoCam is a novel lightweight handheld video microscope.
The
optical system has been designed for the purpose of microcirculation
imaging. It is based on a a set of high resolution lenses with a
magnification factor x4 and provides an optical resolution of more than
300 lines/mm which is a 50 % improvement over earlier devices and
provides a significant improvement on image quality
The probe incorporates Incident Dark Field (IDF) illumination, based on the work of Sherman and Cook [1].
It uses 12 Green LEDS with high brightness. The LED’s are controlled by a control unit which generates a pulse with a duration of 2 ms. The control unit synchronizes the pulse with the clock signal of the sensor exposure. This short light pulse and the short exposure result in sharper contours of fast moving RBCs.
The camera is fully digital and contains a high-resolution sensor with a pixel size of 1,4 micron. As it is used in binning mode the effective pixel size is 2,8 micron, resulting in a 3.5 megapixel frame size. The combination of a 4x optical magnification with the sensor image area provides a 1,55 x 1,16 mm field of view, which is almost twice as large as the field of view of earlier devices.
Additionally, a completely new feature is the quantitative focusing mechanism. This feature uses a linear motor drive, which positions the sensor within 2 microns. Furthermore, it significantly eases the focusing problem. Once the focus depth for a specific patient has been established repeated measurements can be made without the need for subsequent focus adjustments, which significantly reduces the measurement time allowing serial measurements to be easily made.
The CytoCam is a pen like device and is held as such. The low weight of the device (120 gram) minimizes pressure artifact problems that were present in the earlier heavy devices.
The camera is connected to a device controller based on a medical grade computer or a suitable portable device such as laptop or tablet, which is used for image storage. The device controller connects to the camera with a USB3 based camera adapter with a dedicated microprocessor for controlling the camera.
[1] Sherman H, Klausner S, Cook WA (1971)Incident dark-field illumination: a new method for microcirculatory study. Angiology;22(5):295-303.
Intended use
This product is intended to be used for visualisation of micro-circulation in tissue in:
- orifices of the human body which may be non-invasively accessed
- cutaneous surfaces
All other uses are not allowed unless under the following conditions
- the purpose of the usage as device in a research study approved by an academic institution
- the device has been scrutinised and approved by the safety authorities of the institution
- the measurement protocol has been approved by the medical ethical committee of the institution
the measurement has been explained to the study subject and his agreement has been obtained
Limitations
It must be clear that the CytoCam system does not give any advise or direction how to treat a patient. The physician will remain responsible for choosing a specific therapy and to monitor the progress of the condition of the patient, but it very well can support the physician to take better decisions. As such it is a complementary tool to guide therapy.
Application research
Research is being done on the use of the microcirculaion assessment as a tool with potential applications in several areas, including:
- Critical Care Medicine
- Abdominal / Cardiac Surgery
- Urogynaecology
- Cardiology
- ECMO
- LVAD placement
Optional Analysis software for research purposes
Additional software can be used to analyze the images and determine well known microcirculatory parameters such as:
- Total Vessel Density (TVD)
- Perfused Vessel Density (PVD)
- Flow velocity by use of Space Time Diagrams
- Microcirculatory Flow Index (MFI)
The analysis software may be used on a separate system for off-line analysis.