LYMPHATIC ANASTOMOSIS DEVICES AND METHODS
20220354499 · 2022-11-10
Assignee
Inventors
Cpc classification
A61B34/20
HUMAN NECESSITIES
A61B2090/3983
HUMAN NECESSITIES
A61B2034/107
HUMAN NECESSITIES
A61B90/14
HUMAN NECESSITIES
A61B17/11
HUMAN NECESSITIES
A61B2034/108
HUMAN NECESSITIES
A61B2090/3966
HUMAN NECESSITIES
A61B90/30
HUMAN NECESSITIES
International classification
Abstract
Preferred embodiments relate to devices for performing a lymphovenous bypass procedure. A first ring is secured to tissue connected to at least one lymphatic channel of a patient and a second ring is attached to a vein of the patient. An end of the lymphatic channel that extends through the first ring is inserted into an open end of the vein and the rings are connected together to establish fluid flow from the lymphatic channel into the vein.
Claims
1-39. (canceled)
40. A method of performing a lymphovenous bypass surgical procedure comprising: inserting a lymphatic channel coupling device into a surgical opening of a patient; attaching a first coupling device element to tissue that includes a lymphatic channel of a patient; attaching a second coupling device element to a vein of the patient; coupling the lymphatic channel to the vein; and connecting the first coupling device element to the second coupling device element to thereby couple the lymphatic channel to the vein.
41. The method of claim 40 further comprising inserting a plurality of lymphatic channels into the vein of the patient.
42. The method of claim 40 wherein attaching the first coupling device element to tissue further comprises inserting pins on a ring of the first coupling device element into the tissue.
43. The method of claim 40, wherein the lymphatic channel has a smaller diameter then the vein and intercepts the vein by extending a distance into the vein.
44. The method of claim 40, further comprising attaching a plurality of lymphatic channels that are positioned within surrounding tissue to the first coupling device.
45. The method of claim 40, further comprising imaging a region of a patient to generate image data and mapping lymphatic channels in the region.
46. The method of claim 45 further comprising selecting one or more lymphatic channels for a bypass procedure from the mapped image data.
47. The method of claim 40, further comprising inserting the plurality of channels to a depth of at least 1 mm inside the vein.
48. The method of claim 40, further comprising coupling at least 3 lymphatic channels into a single vein.
49. The method of claim 40, further comprising inserting the lymphatic channel to a sidewall of a vein with a vein tributary.
50. The method of claim 40, further comprising measuring a flow of the lymph fluid into the vein or a vein tributary.
51. The method of claim 40, further comprising imaging the coupling of the lymphatic channel into the vein or a vein tributary.
52. The method of claim 40, wherein pins or prongs latch the first coupling element to the second coupling element.
53. The method of claim 40, wherein the lymphatic channel coupling device connects a first lymphatic vessel to a first vein, the method further comprising connecting a second lymphatic vessel to a second vein with a second lymphovenous bypass device.
54. The method of claim 40, wherein the device is implanted into an arm of a patient to treat lymphedema.
55. The method of claim 40, wherein the device is implanted into a leg of a patient.
56. The method of claim 40, further comprising connecting the first coupling element to the second coupling element with a connector.
57. The method of claim 56 wherein the connector comprises a housing that encloses a junction in the vein, the lymphatic channels delivering lymph fluid into the vein at the junction.
58. The method of claim 56 wherein the connector comprises a plurality of pins or prongs.
59. The method of claim 40, further comprising a valve that contacts the vein to constrict flow within the vein.
60. The method of claim 40, further comprising robotically performing one or more steps of the method wherein a plurality of robotic arms holding a corresponding plurality of microsurgical tools grasp at least one of the first coupling element and the second coupling element to connect the elements for implantation into a patient.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE DRAWINGS
[0028] Preferred embodiments of the invention utilize a device for coupling one or more lymphatic channels to the vein of a patient's circulatory system. Shown in
[0029] The components in
[0030] Components of the device can be made using biocompatible materials such as silicone, polyurethane, polytetrafluoroethylene (PTFE), polyesther, polyethylene, polyamide, polyetheretherketone (PEEK), polypropylene, Mylar, Kevlar, polyisoprene, polyolefin, or combinations thereof.
[0031] The first coupling element can comprise a ring having a larger opening to accommodate a thickness of fatty tissue, such as visceral adipose tissue (containing lymphatic vessels with channels extending through the vessels to transport lymph fluid), to extend therethrough and surround the lymphatic tissue, which consequently does not contact the connector surfaces. Note that ring elements can have other shapes, such as an oval cross-section, or some other shape suitable for a specific anatomical placement in the patient. The outer surface is preferably smooth to avoid abrading adjacent tissue. Lymphatic vessels are thin walled tubular shaped tissue structures that are lined with endothelial cells and comprise smooth muscle that is connected to surrounding tissue with adventitia. Lymphatic capillaries are smaller, without the muscle and adventitia, and range in diameter from 15-75 microns. The larger lymphatic vessels have valves spaced along their length with fluid movement provided by peristalsis to move lymph fluid through the vessel under fluid pressure. Lymphatic collecting vessels have a diameter in a range of 100-200 microns. A vein of the vascular system can have a diameter of 1 mm or more and can be selected to receive two or more lymphatic channels for each vein selected. The present devices and methods can also be used to couple to one or more smaller tributary veins that feed into a larger vein. The inner surface of the central opening in an inner ring can be large enough to allow passage of the vein through the central opening such that the exposed end of the vein can be attached to the second connector. Thus, the second connector 120 can have the inner ring 124, with pins, prongs, or tissue anchors 125 that engage the tissue of the vein 129 that folds over the pins 125. The outer ring 122 has pin receiving regions 126 that receive and engage the ends of pins 102, for example, that protrude above the ring surface at an elevation sufficient to at least engage the tissue. Region 126 can be configured to snap together with at least some of the protruding elements or pins 102 from surface of ring 100 to provide a snap connector. A latching mechanism or other connector can be used to secure the coupling elements together. These features are illustrated in one or more of the figures described herein.
[0032] Note that ring element 124 can be elevated above the surface of ring 122 by one or more millimeters. Peripheral wall 121 can thus have a height of at least 1 mm. This can provide for the insertion of lymphatic channels 106 to be a depth of at least 1 mm into the vein 128, for example. Thus, the relative dimensions of the coupling elements can define a depth of insertion.
[0033] Shown in
[0034] The embodiments described herein can be encapsulated within an outer sheath 276 extending around the rings that are aligned along a common axis upon being connected together. The first coupling element or ring can be connected to the second coupling element with one or more connector elements. As described herein, connector elements such as pins, posts or prongs can be used. As shown in
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[0036] Shown schematically in
[0037] Dyes can be used to aid in visualization and mapping of the lymphatic system. Fluorescein isothiocyanate (FITC), for example, is excited in the visible spectrum and routinely used in the operating room. Neurosurgeons inject this dye intravenously and utilize microscopes equipped with filter technology to visualize tumors while maintaining life-like color of the surrounding tissues allowing for simultaneous magnification and tissue dissection. This is important for the lymphatic surgeon. Thus FITC can be used in the operating room for lymphatic mapping. Note, further that FITC has been utilized to perform a lymphovenous bypass (LVB) in the superficial tissues of the arm in a patient with chronic lymphedema. FITC is a safe and highly effective dye for lymphatic mapping and dissection in open surgical fields such as in the LYMPHA procedure.
[0038] Lymphedema repository data on all breast cancer patients that underwent the LYMPHA procedure included demographic information (age, body mass index [BMI]) and peri-operative data have been obtained (number of lymphatic channels visualized and bypassed, distance of channels from axillary vein, name of targeted vein, and adverse events).
[0039] In an exemplary procedure (see Spiguel et al. “Fluorescein Isothiocynate: A Novel Application for Lymphatic Surgery”, Annals of Plastic Surgery, Volume 78 (2017), the entire contents of which is incorporated herein by reference), prior to the ALND, 2 cc of a modified 2% fluorescein solution are injected intradermally and along the muscle fascia of the ipsilateral upper arm, for example. The solution can be modified from the stock AK-FLUOR 10% (Akorn Inc, Lake Forest, IL) solution by diluting 2 cc with 7.5 cc of normal saline and 0.5 cc of AlbuRx5 (CSL Behring Inc, King of Prussia, PA). The ALND is performed with attention to preserving a superficial accessory vein tributary which longitudinally traverses the level I lymph nodes. The superior dissection of the level I axillary contents along the axillary vein is performed with identification of the accessory vein tributary which is typically found anterior to the thoracodorsal neurovascular bundle. The vein is then dissected free from the level I axillary contents and clipped distally to provide maximal length. Completion of the level I and II ALND is then performed.
[0040] Following completion of the axillary dissection, for example, a Pentero 900D Microscope (Carl Zeiss Inc, Germany) equipped with the YELLOW 560 package, can be utilized to identify and map the divided lymphatic channels draining the arm. The harvested vein is prepared per standard microsurgical techniques. Utilizing existing techniques, a surgeon, using 9-0 nylon suture, places a “U” stitch to capture the anterior wall of the vein and parachute in the lymphatic channels chosen for bypass. 10-0 nylon can then be utilized to suture the wall of the vein to the perilymphatic tissue. Channels not bypassed are clipped. Lymphatic flow filling the vein can be visualized with the filter activated one hour after anastomosis.
[0041] However, in accordance with selected embodiments, the surgeon, instead of suturing, will attached the perilymphatic tissue to a first connecting element and attach the vein to a second connecting element, insert the exposed ends of the lymphatic channels into the opening at the vein and connect these components to securely complete the anastomosis or intussusception of lymphatic channels into the vein.
[0042] As noted in the study by Spiguel, et al, thirteen patients underwent LYMPHA with intra-operative FITC lymphatic imaging from March to September 2015. Average patient age was 50 years with a mean BMI of 28. On average, 3.4 divided lymphatic channels (range 1-8) were identified at an average distance of 2.72 cm (range 0.25-5 cm) caudal to the axillary vein. 1.7 channels were bypassed per patient (0-4). Anastomoses were performed to the accessory branch of the axillary vein and or to a lateral branch. LYMPHA added an average of 67 minutes (45-120 minutes) to the oncologic procedure in these examples.
[0043] Thus, FITC is a safe and effective dye for the LYMPHA technique. In comparison to ICG and blue dye, FITC has many advantages. FITC does not permanently stain surrounding tissues, as opposed to ICG and blue dyes, which facilitates dissection of the lymphatic channels. The primary advantage of FITC over ICG in lymphatic surgery, for example, is the ability to allow for simultaneous visualization and dissection of lymphatic channels as FITC is excited in the visible spectrum making it a dye to be used in open surgical fields.
[0044] Diagnosed breast cancer patients can have a lymphedema evaluation pre-operatively. Each evaluation, pre-operatively and post-operatively, can include three components: (1) evaluation by a certified lymphedema therapist for signs and symptoms of BCRL, (2) circumferential measurements, and (3) bioimpedance spectroscopy. Lymphedema can be defined as having signs/symptoms of BCRL and one positive objective measure and can be transient or extend beyond 6 months, for example. Demographics (age, BMI, prior radiation or chemotherapy), cancer treatment characteristics (chemotherapy, type of radiation treatment, and surgical management), and physical therapy evaluations (circumferential measurements, bioimpedance spectroscopy data, follow-up) can be included in the analysis.
[0045] An ALND procedure includes resection of axillary level I and II nodes. Patients undergoing an ALND can undergo identification of divided lymphatics with FITC and subsequently re-route those channels into a preserved axillary vein tributary.
[0046] Demographics and potential risk factors for development of lymphedema such as age, body mass index, clinical stage, radiotherapy, and chemotherapy were reviewed. Similarly, patients who underwent the LYMPHA technique were compared to those who only had ALND.
[0047] All p-values were computed using the Fisher Exact Test or two-tailed t-test, as appropriate. Computations were done in the R language for statistical computing, version 3.3.2. A power analysis can be performed using SAS with the Fischer's Exact Conditional Test, for example. This utilized a set control percentage of 0.40 based on our institutional data. As previously noted, the incidence of lymphedema after simultaneous lymphovenous bypass was 0.04. Conservatively, in evaluating this procedure the power can be set at 0.8.
[0048] In a study conducted by Hahamoff et al (“A Lymphatic Surveillance Program for Breast Cancer Patients Reveals the Promise of Surgical Prevention”, Journal of Surgical Research, 2017, 10.008, the entire contents of which is incorporated here by reference) 177 patients presented for a pre-operative lymphedema evaluation and 87 patients (49%) participated in the program over the period. 45% (67/145) of patients undergoing sentinel lymph node (SLN) biopsy and 64% (18/28) of patients undergoing ALND participated in the program and had an average age of 60 (range 32-83) and BMI 30 (range 17-46). 40% underwent a mastectomy and 21% underwent an ALND. 18% received neoadjuvant chemotherapy and 24% received RLNR. Most patients in this example did not undergo any reconstruction (62%).
[0049] The single most significant risk factor for the development of lymphedema was an ALND (p<0.001). Undergoing mastectomy (p=0.02), adjuvant chemotherapy (p=0.03), and RLNR (p=0.05) were also associated with lymphedema development. A trend towards lymphedema development and clinical stage III disease (p=0.10) was also noted.
TABLE-US-00001 TABLE 1 Advantages and disadvantages of the two most commonly used fluorophores in lymphatic surgery (Blue Dye and ICG) in comparison to FITC. Dye Advantages Disadvantages Blue Dye Technical Technical ✓Visualized through Binoculars XNo Depth of Penetration (Live Surgery) XPermanent Staining ✓No Specialized Equipment Necessary Safety XAdverse Reactions Skin Necrosis (Methylene Blue) Anaphylaxis (Isosulfan Blue) XCross Reactivity Sulfa Drugs (Isosulfan Blue) SSRI (Methylene Blue) ICG Technical Technical ✓Depth of penetration = 20 mm XUnable to visualize through binoculars (No Live Surgery) Safety XPermanent staining ✓No adverse reactions (dermal) XRequires Specialized Equipment ✓No cross-reactivities FITC Technical Technical ✓Visualized Through Binoculars XRequires Specialized Equipment (Live Surgery) ✓Depth of penetration = 5 mm ✓No permanent staining Safety ✓No adverse reactions (dermal) ✓No cross reactiveties
[0050] All patients who developed lymphedema were initially diagnosed either during treatment or within six months of the completion of their cancer therapy. Therefore, all patients were initially diagnosed with transient lymphedema. The average time to diagnosis after the surgical procedure was 4.7 months. One patient in the SLN biopsy group developed transient and then persistent lymphedema ( 1/67 or 1.5%). Of five patients who developed transient lymphedema after undergoing an ALND without the LYMPHA procedure, one patient's symptoms and objective measures completely resolved and four patients' symptoms persisted and they developed lymphedema ( 4/10 or 40%). Of these four patients, three were diagnosed with lymphedema based on changes in symptoms with associated changes in circumferential measurements and bioimpedance spectroscopy. The fourth patient was diagnosed based on symptoms and changes in circumferential measurements alone. Of the 17 patients who underwent the LYMPHA procedure during the period, only eight participated in our surveillance program. One patient in the ALND+LYMPHA group developed transient lymphedema which was persistent but still within six months of the completion of adjuvant radiation therapy (⅛ or 12.5%). This patient's diagnosis was based on changes in symptoms and bioimpedance without change in circumferential measurements. The only significant difference between the two groups undergoing ALND with or without LYMPHA was the follow-up period of 15 months versus 20 months (p<0.03), respectively.
[0051] In a comparison of patients who underwent ALND with or without LYMPHA versus those lost to follow-up in order to identify any potential confounding factors or bias, the only difference between groups noted is that participants who underwent LYMPHA were 10 years older than those patients lost to follow-up (59 vs 49, p=0.04).
[0052] With no cure to date for BCRL, recognition and prophylactic treatment for high-risk patients is an important consideration. The rate of lymphedema after ALND can be reduced from 40% to 12.5% after introduction of the LYMPHA approach in this example. Similarly, it is preferable to identify lymphedema in patients undergoing ALND within five months of their procedure. ALND, mastectomy, adjuvant chemotherapy, and RLNR were associated with the development of lymphedema.
[0053] A notable finding of the Hahamoff et al, study was the reduction in rate of lymphedema development from 40% to 12.5% in patients undergoing an ALND after the introduction of the LYMPHA technique.
[0054] Note that the patients who develop lymphedema presented initially with signs and symptoms either during treatment or within six months of the end of their cancer therapy. Of these patients, one patient's condition completely resolved. No patient, to date, has presented with lymphedema more than six months after the completion of cancer therapy. This finding underscores the value of surveillance in being able to detect early lymphedema which is especially important for high-risk patients as prompt detection and treatment can potentially slow the progression of disease.
[0055] ALND and RLNR are important risk factors for the development of lymphedema. There can be increased rate of lymphedema in patients undergoing mastectomy, and this can be explained by the indications for ALND. Specifically, patients with limited nodal involvement undergoing lumpectomy do not require an ALND while those undergoing mastectomy will undergo an ALND for the same extent of nodal involvement. Therefore, patients undergoing mastectomy receive more aggressive axillary management than those undergoing lumpectomy. There can be increased rates of lymphedema for patients who underwent adjuvant chemotherapy, which again, may be biased as those undergoing chemotherapy are more likely to have presented with more advanced disease initially. However, studies have linked specific chemotherapy regimens to the development of lymphedema. Lastly, as patients presenting for ALND have more advanced disease, it is not surprising that increased rates of lymphedema development were noted in those with clinical stage 3 disease.
[0056] While surgical prevention can aid in improving the quality of life in breast cancer survivors, development of our program did have its challenges. When SLNs were sent for permanent section and the patient returned to the operating room for an ALND at a later date, scheduling combination procedures between a breast and plastic surgeon were effective. However, when SLNs were sent for frozen section, the scheduling can be more erratic as a larger percentage of patients will never progress to ALND especially in light of recent trials challenging the need for ALND.
[0057] The present devices and methods for the treatment of lymphedema can change how metastatic disease to the axilla is treated. Given the significant morbidity of ALND, namely lymphedema, there is a distinct push away from ALND in early stage breast cancer in place of RLNR. However, with improved LYMPHA procedures and the promise of lower rates of lymphedema, the role of ALND in providing an improved method of loco-regional control can be enhanced.
[0058] A significant finding was that a decrease in lymphedema rates after the advent of LYMPHA are notable as the average time to diagnosis of lymphedema was 4.7 months following the surgical intervention. In this example, the total follow-up time in the ALND versus ALND+LYMPHA groups was 20 months and 15 months, respectively.
[0059] Offering LYMPHA with ALND together decreased the rate of lymphedema from 40% to 12.5%. Similarly, surveillance after surgery can provide early diagnosis and intervention by physical therapy. The significant risk factors for lymphedema development included ALND, RLNR, adjuvant chemotherapy, and mastectomy.
[0060] Note that breast surgeons often prefer to use a dual tracer method including both blue dye and technetium sulfur colloid for sentinel lymph node (SLN) identification. This is especially important in cases where neoadjuvant chemotherapy has previously been administered. Therefore, a different dye was sought for arm lymphatic mapping to differentiate staining from arm versus breast lymphatics. Thus, a combination of visualization procedures can be used. Shown in
[0061] The most common method of lymphatic vessel mapping currently in use is indocyanine green (ICG). However, the challenge with ICG is that the dye is near-infrared and therefore excited in the non-visible spectrum. This limits the usefulness of ICG for visualization and simultaneous dissection as the dye is displayed as a white signal on a black background and can not be concurrently visualized through the binoculars of a microscope.
[0062] Illustrated in
[0063] Illustrated in connection with
[0064] As shown in
[0065] It will be appreciated by those skilled in the art that modifications to, and variations of the above described device and methods can be made without departing from the inventive concepts disclosed herein. Accordingly, the disclosure should not be viewed as limited except as by the scope and spirit of the appended claims.