FIELD

Disclosed embodiments are related to medical imaging devices and their methods of use.

BACKGROUND

There are over one million cancer surgeries per year performed in the United States and nearly 40% of them miss resecting the entire tumor according to the National Cancer Institute Surveillance Epidemiology and End Results report. For example in breast cancer lumpectomies, failure to remove all of the cancer cells during the primary surgery (positive margins) occurs approximately 50% of the time and requires second surgeries. Residual cancer in the surgical bed is a leading risk factor for local tumor recurrence, reduced survival rates and increased likelihood of metastases. In addition, final histopathology of the resected tumor misses 25% of the residual cancer left in the surgical bed, which must be addressed with adjuvant medical therapy (e.g. radiotherapy or chemotherapy). This poor performance of pathology is primarily due to a sampling error since only a small fraction of the entire resection is analyzed.

In a typical solid tumor resection, the surgeon removes the bulk of the tumor and sends it to pathology. The pathologist then samples the bulk tumor in a few locations and images a stained section under a microscope to determine if the surgeon has completely removed all of cancer cells from the patient. Should the pathologist find a portion of the stained sample with cancer cells bordering ink (a diagnostic known in the medical realm as “positive margin”), the surgeon may be instructed to resect more tissue. However this pathology exercise is a time intensive procedure and often takes days for final results to be sent to the physician. Should a pathology report requiring additional resection return after the patient has completed the initial surgery, this may require the surgeon to perform a second surgery.

In addition to determining clean margins, some surgeries involving the removal of cancerous tissue adjacent to vital tissue structures, such as neurovascular bundles, require precise localization of abnormal tissue to remove the necessary amount of abnormal tissue while avoiding these vital tissue structures as much as possible. Surgeries that require such precise, real-time localization, may include ovarian cancer debulking, brain cancer resection, sarcoma resection, open prostate tumor resection, esophageal cancer resection, and open colo-rectal tumor resection, among others. In the case of ovarian cancer debulking, survival rates correlate directly with the amount of residual cancer left in the wound. A patient is deemed “optimally” debulked if no tumor features larger than 1 cm remain at the end of surgery. With ovarian cancer debulking surgery, 83% of the time, cancer remains in the patient, and of those cases, 50% require reexcision surgeries.

Recent advances have been made for in situ observation of residual cancer cells in a tumor resection bed. See, for example, U.S. Patent Application publication numbers 2009/0299196, 2011/0100471 and 2012/0150164, the disclosures of which are incorporated herein by reference in their entirety. The present application is directed to a hand-held device and related technology for performing such in situ observation of residual cancer cells in a tumor resection bed.

SUMMARY

In one embodiment, a handheld medical imaging device may include a photosensitive detector comprising a plurality of pixels and a rigid imaging tip optically associated with the photosensitive detector. The rigid imaging tip may include a distal end defining a focal plane at a fixed focal distance relative to the photosensitive detector, and the distal end of the rigid imaging tip may be constructed to be placed in contact with tissue and maintain the tissue at the focal plane.

In another embodiment, a hand held medical imaging device may include an imaging device body and a rigid imaging tip distally extending from the imaging device body. A distal end of the rigid imaging tip may define a focal plane with a field of view with a lateral dimension between about 10 mm to 50 mm inclusively. The rigid imaging tip may also include a proximal portion and a distal portion that is angled by about 25° to 65° inclusively relative to the proximal portion. A length of the distal angled portion may be between about 10 mm to 65 mm, and an optical axis may pass through the rigid imaging tip from the distal end of the rigid imaging tip to the proximal end of the rigid imaging tip.

In yet another embodiment, a hand held medical imaging device may include a photosensitive detector comprising a plurality of pixels and a rigid imaging tip optically associated with the photosensitive detector. The rigid imaging tip may include a distal end defining a focal plane relative to the photosensitive detector, and the distal end of the rigid imaging tip may be open. The rigid imaging tip may include at least one opening on a side of the rigid imaging tip that is sized and shaped to provide surgical access to the distal end of the rigid imaging tip.

In another embodiment, a hand held medical imaging device may include a rigid imaging tip including a proximal portion and a distal portion including a distal end. The distal end may include an opening to provide access to a surgical bed and one or more supports extending between the proximal portion and the distal portion. A photosensitive detector may be optically associated with the opening located in the distal end of the rigid imaging tip.

In yet another embodiment, a handheld medical imaging device may include a rigid imaging tip including a distal end defining a field of view and a photosensitive detector optically associated with the rigid imaging tip. A first illumination source may be adapted and arranged to provide light with a first wavelength to the distal end of the rigid imaging tip. A second illumination source may also be adapted and arranged to provide light with a second wavelength to the distal end of the rigid imaging tip. The first wavelength and the second wavelength may be different. Additionally, the first illumination source and the second illumination source may be adapted to alternatingly pulse.

In another embodiment, a handheld medical imaging device may include a rigid imaging tip including a distal end defining a focal plane with a field of view. A photosensitive detector may be optically associated with the rigid imaging tip and an aperture may be located between the photosensitive detector and the rigid imaging tip. The aperture may have a diameter between about 5 mm to 15 mm inclusively. The handheld medical imaging device may also include a first illumination source adapted and arranged to provide between about 10 mW/cm2to 200 mW/cm2of light at the focal plane, wherein the light has a first wavelength between about 300 nm to 1,000 nm.

In yet another embodiment, a method for identifying abnormal tissue may include: providing a first light comprising a first excitation wavelength to a surgical bed; collecting a fluorescence signal from the surgical bed using a photosensitive detector; comparing the fluorescence signal to an abnormal tissue threshold to identify abnormal tissue; and indicating one or more locations of the identified abnormal tissue on a screen.

In another embodiment, a method for identifying abnormal tissue may include: illuminating a surgical bed with a first light comprising a first excitation wavelength of a imaging agent using a first illumination source; illuminating the surgical bed with a second light comprising a second wavelength different from the first excitation wavelength using a second illumination source; and collecting a signal from the surgical bed using a photosensitive detector.

In yet another embodiment, a method for identifying abnormal tissue may include: illuminating the surgical bed with ambient light; illuminating a surgical bed with a first light comprising a first excitation wavelength of an imaging agent by pulsing a first illumination source; collecting a first signal from the surgical bed corresponding to ambient light using a photosensitive detector including a plurality of pixels; and collecting a second signal from the surgical bed corresponding to ambient light and a pulse of the first illumination source.

It should be appreciated that the foregoing concepts, and additional concepts discussed below, may be arranged in any suitable combination, as the present disclosure is not limited in this respect. Further, other advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments when considered in conjunction with the accompanying figures.

