1
|
Van Den Hoven P, Osterkamp J, Nerup N, Svendsen MBS, Vahrmeijer A, Van Der Vorst JR, Achiam MP. Quantitative perfusion assessment using indocyanine green during surgery - current applications and recommendations for future use. Langenbecks Arch Surg 2023; 408:67. [PMID: 36700999 PMCID: PMC9879827 DOI: 10.1007/s00423-023-02780-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/12/2022] [Indexed: 01/27/2023]
Abstract
PURPOSE Incorrect assessment of tissue perfusion carries a significant risk of complications in surgery. The use of near-infrared (NIR) fluorescence imaging with Indocyanine Green (ICG) presents a possible solution. However, only through quantification of the fluorescence signal can an objective and reproducible evaluation of tissue perfusion be obtained. This narrative review aims to provide an overview of the available quantification methods for perfusion assessment using ICG NIR fluorescence imaging and to present an overview of current clinically utilized software implementations. METHODS PubMed was searched for clinical studies on the quantification of ICG NIR fluorescence imaging to assess tissue perfusion. Data on the utilized camera systems and performed methods of quantification were collected. RESULTS Eleven software programs for quantifying tissue perfusion using ICG NIR fluorescence imaging were identified. Five of the 11 programs have been described in three or more clinical studies, including Flow® 800, ROIs Software, IC Calc, SPY-Q™, and the Quest Research Framework®. In addition, applying normalization to fluorescence intensity analysis was described for two software programs. CONCLUSION Several systems or software solutions provide a quantification of ICG fluorescence; however, intraoperative applications are scarce and quantification methods vary abundantly. In the widespread search for reliable quantification of perfusion with ICG NIR fluorescence imaging, standardization of quantification methods and data acquisition is essential.
Collapse
Affiliation(s)
- P Van Den Hoven
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
| | - J Osterkamp
- Department of Surgery and Transplantation, Copenhagen University Hospital Rigshospitalet, The Capital Region of Denmark, Copenhagen, Denmark
| | - N Nerup
- Department of Surgery and Transplantation, Copenhagen University Hospital Rigshospitalet, The Capital Region of Denmark, Copenhagen, Denmark
| | - M B S Svendsen
- CAMES Engineering, Copenhagen Academy for Medical Education and Simulation, Centre for Human Resources and Education, The Capital Region of Denmark, Copenhagen, Denmark
| | - Alexander Vahrmeijer
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - J R Van Der Vorst
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - M P Achiam
- Department of Surgery and Transplantation, Copenhagen University Hospital Rigshospitalet, The Capital Region of Denmark, Copenhagen, Denmark
| |
Collapse
|
2
|
Van Den Hoven P, Tange F, Van Der Valk J, Nerup N, Putter H, Van Rijswijk C, Van Schaik J, Schepers A, Vahrmeijer A, Hamming J, Van Der Vorst J. Normalization of Time-Intensity Curves for Quantification of Foot Perfusion Using Near-Infrared Fluorescence Imaging With Indocyanine Green. J Endovasc Ther 2022; 30:364-371. [PMID: 35236169 DOI: 10.1177/15266028221081085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) is gaining popularity for the quantification of tissue perfusion, including foot perfusion in patients with lower extremity arterial disease (LEAD). However, the absolute fluorescence intensity is influenced by patient-and system-related factors limiting reliable and valid quantification. To enhance the quality of quantitative perfusion assessment using ICG NIR fluorescence imaging, normalization of the measured time-intensity curves seems useful. MATERIALS AND METHODS In this cohort study, the effect of normalization on 2 aspects of ICG NIR fluorescence imaging in assessment of foot perfusion was measured: the repeatability and the region selection. Following intravenous administration of ICG, the NIR fluorescence intensity in both feet was recorded for 10 mins using the Quest Spectrum platform®. The effect of normalization on repeatability was measured in the nontreated foot in patients undergoing unilateral revascularization preprocedural and postprocedural (repeatability group). The effect of normalization on region selection was performed in patients without LEAD (region selection group). Absolute and normalized time-intensity curves were compared. RESULTS Successful ICG NIR fluorescence imaging was performed in 54 patients (repeatability group, n = 38; region selection group, n = 16). For the repeatability group, normalization of the time-intensity curves displayed a comparable inflow pattern for repeated measurements. For the region selection group, the maximum fluorescence intensity (Imax) demonstrated significant differences between the 3 measured regions of the foot (P = .002). Following normalization, the time-intensity curves in both feet were comparable for all 3 regions. CONCLUSION This study shows the effect of normalization of time-intensity curves on both the repeatability and region selection in ICG NIR fluorescence imaging. The significant difference between absolute parameters in various regions of the foot demonstrates the limitation of absolute intensity in interpreting tissue perfusion. Therefore, normalization and standardization of camera settings are essential steps toward reliable and valid quantification of tissue perfusion using ICG NIR fluorescence imaging.
Collapse
Affiliation(s)
- Pim Van Den Hoven
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Floris Tange
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Jurrian Van Der Valk
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Nikolaj Nerup
- Department of Surgical Gastroenterology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Hein Putter
- Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands
| | - Catharina Van Rijswijk
- Department of Interventional Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan Van Schaik
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Abbey Schepers
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Alexander Vahrmeijer
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Jaap Hamming
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Joost Van Der Vorst
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
3
|
Van Den Hoven P, Goncalves LN, Quax PHA, Van Rijswijk CSP, Van Schaik J, Schepers A, Vahrmeijer AL, Hamming JF, Van Der Vorst JR. Perfusion Patterns in Patients with Chronic Limb-Threatening Ischemia versus Control Patients Using Near-Infrared Fluorescence Imaging with Indocyanine Green. Biomedicines 2021; 9:biomedicines9101417. [PMID: 34680534 PMCID: PMC8533354 DOI: 10.3390/biomedicines9101417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/04/2021] [Accepted: 10/06/2021] [Indexed: 01/01/2023] Open
Abstract
In assessing the severity of lower extremity arterial disease (LEAD), physicians rely on clinical judgements supported by conventional measurements of macrovascular blood flow. However, current diagnostic techniques provide no information about regional tissue perfusion and are of limited value in patients with chronic limb-threatening ischemia (CLTI). Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has been used extensively in perfusion studies and is a possible modality for tissue perfusion measurement in patients with CLTI. In this prospective cohort study, ICG NIR fluorescence imaging was performed in patients with CLTI and control patients using the Quest Spectrum Platform® (Middenmeer, The Netherlands). The time–intensity curves were analyzed using the Quest Research Framework. Fourteen parameters were extracted. Successful ICG NIR fluorescence imaging was performed in 19 patients with CLTI and in 16 control patients. The time to maximum intensity (seconds) was lower for CLTI patients (90.5 vs. 143.3, p = 0.002). For the inflow parameters, the maximum slope, the normalized maximum slope and the ingress rate were all significantly higher in the CLTI group. The inflow parameters observed in patients with CLTI were superior to the control group. Possible explanations for the increased inflow include damage to the regulatory mechanisms of the microcirculation, arterial stiffness, and transcapillary leakage.
Collapse
Affiliation(s)
- Pim Van Den Hoven
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Lauren N. Goncalves
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Paulus H. A. Quax
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | | | - Jan Van Schaik
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Abbey Schepers
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Alexander L. Vahrmeijer
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Jaap F. Hamming
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
| | - Joost R. Van Der Vorst
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (P.V.D.H.); (L.N.G.); (P.H.A.Q.); (J.V.S.); (A.S.); (A.L.V.); (J.F.H.)
- Correspondence: ; Tel.: +31-71-529-9143
| |
Collapse
|
4
|
Van den Hoven P, S Weller F, Van De Bent M, Goncalves LN, Ruig M, D Van Den Berg S, Ooms S, Mieog J, Ea Van De Bogt K, Van Schaik J, Schepers A, Vahrmeijer AL, Hamming JF, Van Der Vorst JR. Near-infrared fluorescence imaging with indocyanine green for quantification of changes in tissue perfusion following revascularization. Vascular 2021; 30:867-873. [PMID: 34320878 DOI: 10.1177/17085381211032826] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES Current diagnostic modalities for patients with peripheral artery disease (PAD) mainly focus on the macrovascular level. For assessment of tissue perfusion, near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) seems promising. In this prospective cohort study, ICG NIR fluorescence imaging was performed pre- and post-revascularization to assess changes in foot perfusion. METHODS ICG NIR fluorescence imaging was performed in 36 patients with PAD pre- and post-intervention. After intravenous bolus injection of 0.1 mg/kg ICG, the camera registered the NIR fluorescence intensity over time on the dorsum of the feet for 15 min using the Quest Spectrum Platform®. Time-intensity curves were plotted for three regions of interest (ROI): (1) the dorsum of the foot, (2) the forefoot, and (3) the hallux. Time-intensity curves were normalized for maximum fluorescence intensity. Extracted parameters were the maximum slope, area under the curve (AUC) for the ingress, and the AUC for the egress. The non-treated contralateral leg was used as a control group. RESULTS Successful revascularization was performed in 32 patients. There was a significant increase for the maximum slope and AUC egress in all three ROIs. The most significant difference was seen for the maximum slope in ROI 3 (3.7%/s to 6.6%/s, p < 0.001). In the control group, no significant differences were seen for the maximum slope and AUC egress in all ROIs. CONCLUSIONS This study shows the potential of ICG NIR fluorescence imaging in assessing the effect of revascularization procedures on foot perfusion. Future studies should focus on the use of this technique in predicting favorable outcome of revascularization procedures.
Collapse
Affiliation(s)
- Pim Van den Hoven
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Floris S Weller
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Merel Van De Bent
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Lauren N Goncalves
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Melissa Ruig
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Simen D Van Den Berg
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Sophie Ooms
- Department of Vascular Surgery, Haga Ziekenhuis, The Hague, The Netherlands
| | - Jsd Mieog
- Department of Surgical Oncology, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Koen Ea Van De Bogt
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Jan Van Schaik
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Abbey Schepers
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Alex L Vahrmeijer
- Department of Surgical Oncology, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Jaap F Hamming
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| | - Joost R Van Der Vorst
- Department of Vascular Surgery, 4501Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
5
|
Goncalves LN, van den Hoven P, van Schaik J, Leeuwenburgh L, Hendricks CHF, Verduijn PS, van der Bogt KEA, van Rijswijk CSP, Schepers A, Vahrmeijer AL, Hamming JF, van der Vorst JR. Perfusion Parameters in Near-Infrared Fluorescence Imaging with Indocyanine Green: A Systematic Review of the Literature. Life (Basel) 2021; 11:life11050433. [PMID: 34064948 PMCID: PMC8151115 DOI: 10.3390/life11050433] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/01/2021] [Accepted: 05/05/2021] [Indexed: 01/16/2023] Open
Abstract
(1) Background: Near-infrared fluorescence imaging is a technique capable of assessing tissue perfusion and has been adopted in various fields including plastic surgery, vascular surgery, coronary arterial disease, and gastrointestinal surgery. While the usefulness of this technique has been broadly explored, there is a large variety in the calculation of perfusion parameters. In this systematic review, we aim to provide a detailed overview of current perfusion parameters, and determine the perfusion parameters with the most potential for application in near-infrared fluorescence imaging. (2) Methods: A comprehensive search of the literature was performed in Pubmed, Embase, Medline, and Cochrane Review. We included all clinical studies referencing near-infrared perfusion parameters. (3) Results: A total of 1511 articles were found, of which, 113 were suitable for review, with a final selection of 59 articles. Near-infrared fluorescence imaging parameters are heterogeneous in their correlation to perfusion. Time-related parameters appear superior to absolute intensity parameters in a clinical setting. (4) Conclusions: This literature review demonstrates the variety of parameters selected for the quantification of perfusion in near-infrared fluorescence imaging.
Collapse
|
6
|
Interpretation of Near-Infrared Imaging in Acute and Chronic Wound Care. Diagnostics (Basel) 2021; 11:diagnostics11050778. [PMID: 33925990 PMCID: PMC8144992 DOI: 10.3390/diagnostics11050778] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 11/16/2022] Open
Abstract
Vascular assessment is a critical component of wound care. Current routine noninvasive vascular studies have limitations which can give a false sense of security of the presence of adequate perfusion for healing. Near-infrared imaging modalities can serve as an additional diagnostic assessment of wounds in which adequate perfusion is a concern. Correct interpretation of near-infrared images obtained is critical as subtleties that exist in the acute and chronic wound population goes beyond the interpretation that increased signal is consistent with adequate perfusion for healing. The objective of this paper is to educate providers on the correct interpretation of this point-of-care imaging modality in day-to-day wound-care practice to guide clinical decision-making for rapid wound resolution.
Collapse
|
7
|
Teso D, Sommerset J, Dally M, Feliciano B, Vea Y, Jones RK. Pedal Acceleration Time (PAT): A Novel Predictor of Limb Salvage. Ann Vasc Surg 2021; 75:189-193. [PMID: 33823258 DOI: 10.1016/j.avsg.2021.02.038] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/22/2021] [Accepted: 02/09/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND In the setting of Peripheral Arterial Disease (PAD), pedal arch interrogation by ultrasound has not been well described. Patients with noncompressible vessels and/or open wounds of the foot may preclude the use of ankle-brachial indices, toe pressure measurements, or TcPO2, respectively. We propose that pedal artery interrogations with Pedal Acceleration Time (PAT) can be a predictor for limb salvage in patients with Chronic Limb-Threatening Ischemia (CLTI). METHODS A retrospective review of a prospectively kept database was performed from 2018 to 2019. Patients with pending amputation due to severe infection (WIFI infection class 2 and 3) were excluded from the study. We identified 73 limbs with CLTI that fit the inclusion criteria. Data included WIFI classification, age, gender, cardiovascular risk factors, PAT, ABI, and TBI when reliable, were collected. PAT measurements were categorized into 4 classifications; 1 (40-120 msec), 2 (121-180 msec), 3 (181-224 msec), and 4 (Greater than 225 msec). Statistical analyses were performed. RESULTS Seventy-three limbs with CLTI were included in our study. All patients underwent arterial revascularization with either percutaneous technique or arterial bypass. Limb salvage was achieved in 59 (81%) of the 73 limbs. All 59 limbs had a 2-classification improvement in their PAT following interventions. A total of 14 (19%) limbs without improvement in their PAT underwent above ankle level amputations. An improvement in PAT classes to class 1 or 2 is associated with limb salvage. CONCLUSIONS Patients with noncompressible ankle pressures or nonobtainable toe pressures poses a challenge in the complete assessment of WIFI classification. Our group has shown that PAT can be used in the scoring system for severity of ischemia in conjunction with current WIFI classification. Our data suggests that limb salvage correlates with post procedure PAT in category 1 and 2. Therefore we propose that PAT be added as part of the WIFI classification.
Collapse
Affiliation(s)
- Desarom Teso
- PeaceHealth Southwest Medical Center, Vancouver, WA; Elson S. Floyd College of Medicine, Washington State University, Pullman, WA.
| | - Jill Sommerset
- PeaceHealth Southwest Medical Center, Vancouver, WA; Elson S. Floyd College of Medicine, Washington State University, Pullman, WA
| | | | - Beejay Feliciano
- PeaceHealth Southwest Medical Center, Vancouver, WA; Elson S. Floyd College of Medicine, Washington State University, Pullman, WA
| | - Yolanda Vea
- PeaceHealth Southwest Medical Center, Vancouver, WA; Elson S. Floyd College of Medicine, Washington State University, Pullman, WA
| | - Riyad Karmy Jones
- PeaceHealth Southwest Medical Center, Vancouver, WA; Elson S. Floyd College of Medicine, Washington State University, Pullman, WA
| |
Collapse
|
8
|
Herraiz-Adillo Á, Cavero-Redondo I, Álvarez-Bueno C, Pozuelo-Carrascosa DP, Solera-Martínez M. The accuracy of toe brachial index and ankle brachial index in the diagnosis of lower limb peripheral arterial disease: A systematic review and meta-analysis. Atherosclerosis 2020; 315:81-92. [DOI: 10.1016/j.atherosclerosis.2020.09.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/05/2020] [Accepted: 09/24/2020] [Indexed: 12/24/2022]
|
9
|
Poredos P. Involvement of microcirculation in critical ischemia: how to identify it? INT ANGIOL 2020; 39:492-499. [PMID: 32594670 DOI: 10.23736/s0392-9590.20.04428-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Critical limb ischemia represents the most severe pattern of peripheral arterial disease (PAD) associated with the high risk of major amputation, cardiovascular events and death. The diagnosis and management of critical limb ischemia (CLI) is often challenging. Systolic ankle and toe pressure measurements are considered to be the basic techniques for the identification of PAD. However, they provide rough insight into the dependent local tissue perfusion. Furthermore, those techniques do not enable investigation of microcirculation which has crucial role in the pathogenesis of CLI. Some patients with mild deterioration of macrocirculation develop CLI if microcirculation is affected. Investigation of perfusion on macro- and local microcirculatory level enables more effective treatment: revascularization of the angiosome-related artery. The technologies capable of assessing limb tissue oxygenation or perfusion on microcirculatory level enable direct assessment of distant tissue oxygenation. Transcutaneous oxygen tension (TcPO2) measurement which was introduced in clinical practice represents one of the objective criteria for the diagnosis of CLI. Main weakness of this technique as well as laser Doppler flow measurement is low penetrance from the skin surface. Measurement of tissue blood flow on microcirculatory level can be performed with indocyanine green fluorescent imaging (ICG), contrast-enhanced magnetic resonance and vital microscopy. ICG is promising method which provides excellent informative image of tissue perfusion. However, it offers little quantitative information. Investigation of microcirculation in patients with CLI is of outmost importance because it enables insight in local tissue perfusion and oxygenation, which represents the basis of identification of most ischemic regions and provide more successful angiosome related revascularization of an affected artery.
Collapse
Affiliation(s)
- Pavel Poredos
- Department of Vascular Disease, University Medical Centre Ljubljana (UMCL), Ljubljana, Slovenia - .,Department of Advanced Cardiopulmonary Therapies and Transplantation, University of Texas Health Science Center at Houston, Houston, TX, USA -
| |
Collapse
|
10
|
Abstract
Peripheral arterial disease (PAD) affects many individuals worldwide and is associated with increased morbidity and mortality. Controversy exists on whether or not to screen asymptomatic patients. Further complicating this is that many patients with a chronic lower extremity wound are often asymptomatic. PAD and traditional noninvasive vascular studies may be inaccurate in providing a correct diagnosis. A review of current and novel vascular assessment modalities along with their benefits and limitations are presented here. A combination of these vascular assessments may help improve accuracy in diagnosis, providing timely care to those patients in need.
Collapse
Affiliation(s)
- Jonathan F Arnold
- Mercy Healing Center, 701 10th Street Southeast, Cedar Rapids, IA 52403, USA.
| |
Collapse
|
11
|
van den Hoven P, Ooms S, van Manen L, van der Bogt KEA, van Schaik J, Hamming JF, Vahrmeijer AL, van der Vorst JR, Mieog JSD. A systematic review of the use of near-infrared fluorescence imaging in patients with peripheral artery disease. J Vasc Surg 2020; 70:286-297.e1. [PMID: 31230648 DOI: 10.1016/j.jvs.2018.11.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 11/19/2018] [Indexed: 01/18/2023]
Abstract
OBJECTIVE In the diagnosis of peripheral artery disease (PAD), the ankle-brachial index plays an important role. However, results of the ankle-brachial index are unreliable in patients with severe media sclerosis. Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) can provide information about tissue perfusion and has already been studied in oncologic, reconstructive, and cardiac surgery. For patients with PAD, this technique might give insight into skin perfusion and thereby guide treatment. We performed a systematic review of the literature on the use of NIR fluorescence imaging in patients with PAD. METHODS PubMed, MEDLINE, Embase, and Cochrane were searched for articles and abstracts on the application of NIR fluorescence imaging using ICG as fluorescent dye in patients with PAD. Our search strategy combined the terms "fluorescence," "ICG," or synonyms and "peripheral artery disease" or synonyms. The extracted data included fluorescence parameters and test characteristics for diagnosis of PAD. RESULTS Twenty-three articles were found eligible for this review using 18 different parameters for evaluation of the fluorescence signal intensity. NIR fluorescence imaging was used for four main indications: diagnosis, quality control in revascularization, guidance in amputation surgery, and visualization of vascular structures. For the diagnosis of PAD, NIR fluorescence imaging yields a sensitivity ranging from 67% to 100% and a specificity varying between 72% and 100%. Significant increases in multiple fluorescence parameters were found in comparing patients before and after revascularization. CONCLUSIONS NIR fluorescence imaging can be used for several indications in patients with PAD. NIR fluorescence imaging seems promising in diagnosis of PAD and guidance of surgeons in treatment, especially in patients in whom current diagnostic methods are not applicable. Further standardization is needed to reliably use this modality in patients with PAD.
Collapse
Affiliation(s)
- Pim van den Hoven
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Sophie Ooms
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Labrinus van Manen
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Jan van Schaik
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Jaap F Hamming
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - J Sven D Mieog
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
| |
Collapse
|
12
|
Evaluation of the Intraoperative Blood Flow of Pedicled Perforator Flaps Using Indocyanine Green-fluorescence Angiography. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2019; 7:e2462. [PMID: 31942410 PMCID: PMC6908407 DOI: 10.1097/gox.0000000000002462] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 07/23/2019] [Indexed: 11/27/2022]
Abstract
Although indocyanine-green fluorescence angiography (ICG-FA) has been established as a useful tool to assess perfusion in free tissue transfer, only few studies have applied this modality to pedicled perforator flaps. As both volume and reach of pedicled perforator flaps are limited and tip necrosis often equals complete flap failure, ICG-FA may help to detect hypoperfusion in pedicled flaps. Methods In 5 patients, soft tissue reconstruction was achieved with pedicled perforator flaps. ICG-FA was utilized intraoperatively to visualize flap perfusion. Results Three pedicled anterolateral thigh flap flaps and 2 propeller flaps were transferred. ICG-FA detected hypoperfusion in 2 flaps. No flap loss occurred; in 2 cases, prolonged wound healing was encountered. Conclusions ICG-FA confirmed clinical findings and reliably detected tissue areas with hypoperfusion. A clear cut-off point between nonvital tissue and such that stabilized in the following clinical course could not be found. ICG-FA is a promising technology which could also be used in pedicled perforator flaps.
Collapse
|
13
|
Ma KF, Kleiss SF, Schuurmann RCL, Bokkers RPH, Ünlü Ç, De Vries JPPM. A systematic review of diagnostic techniques to determine tissue perfusion in patients with peripheral arterial disease. Expert Rev Med Devices 2019; 16:697-710. [PMID: 31340684 DOI: 10.1080/17434440.2019.1644166] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Introduction: Peripheral arterial disease (PAD) may cause symptoms due to impaired tissue perfusion of the lower extremity. So far, assessment of PAD is mainly performed by determination of stenosis or occlusion in the large arteries and does not focus on microcirculation. Several diagnostic techniques have been recently introduced that may enable tissue perfusion measurements in the lower limb; however, most have not yet been implemented in clinical daily practice. This systematic review provides an overview of these diagnostic techniques and their ability to accurately detect PAD by peripheral tissue perfusion. Areas covered: A literature search was performed for articles that described a diagnostic technique to determine tissue perfusion in patients with known PAD compared with healthy controls. Expert opinion: So far, transcutaneous oxygen measurements are most often used to measure tissue oxygenation in PAD patients, but evidence seems too low to define this technique as a gold standard, and implementing this technique for home monitoring is difficult. New potentially suitable diagnostic tests should be non-invasive, contact-free, and quick. Further research is needed for all of these techniques before broad implementation in clinical use is justified, in hospital, and for home monitoring.
Collapse
Affiliation(s)
- Kirsten F Ma
- a Department of Surgery, Division of Vascular Surgery, University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| | - Simone F Kleiss
- a Department of Surgery, Division of Vascular Surgery, University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| | - Richte C L Schuurmann
- a Department of Surgery, Division of Vascular Surgery, University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| | - Reinoud P H Bokkers
- b Department of Vascular Surgery, Noordwest Hospital Group , Alkmaar , The Netherlands
| | - Çagdas Ünlü
- c Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| | - Jean-Paul P M De Vries
- a Department of Surgery, Division of Vascular Surgery, University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| |
Collapse
|
14
|
Abstract
The accurate assessment of peripheral perfusion is a critical step in caring for a diabetic patient with active ulceration. This article guides the provider through diagnostic and therapeutic options. The perfusion assessment begins with a physical examination and augmented using noninvasive tests. Although some of these tests can be performed at the bedside, often a dedicated vascular laboratory is required. Additional cross-sectional imaging studies or formal angiography should be performed as well. These tools aid in the creation of the best therapeutic plan, which aims to restore perfusion and allow for rapid wound healing via open or endovascular means.
Collapse
Affiliation(s)
- Michael Cyrus Siah
- Department of Vascular Surgery, MedStar Washington Hospital Center, 106 Iriving Street Northwest POB North 3150, Washington, DC 20010, USA
| | - Steven Abramowitz
- Department of Vascular Surgery, MedStar Washington Hospital Center, 106 Iriving Street Northwest POB North 3150, Washington, DC 20010, USA.
| |
Collapse
|
15
|
Abstract
UNLABELLED Heel ulcerations are a significant burden of care in both hospital and long-term care settings. The presence of peripheral arterial disease as a contributing factor to delayed healing is often not recognized, resulting in prolonged healing and high patient morbidity and mortality. Formal vascular evaluation and intervention is often not performed as these patients can have palpable pedal pulses while having localized ischemia of the heel. As routine noninvasive vascular studies can be affected by medial calcinosis and collateralization and do not specifically assess tissue perfusion to the heel, a false sense of security of adequate perfusion for healing can result. Indocyanine green fluorescence angiography (ICGFA) allows for real-time visualization and objective assessment of site specific tissue perfusion not limited by the factors that can make routine noninvasive vascular studies unreliable or unobtainable. A retrospective medical record review of a subset of patients with chronic heel ulceration from a prospective institutional review board-approved study in which serial ICGFA was performed during their treatment course was performed. ICGFA was able to identify local heel ischemia and expedite vascular intervention. ICGFA should be considered as an additional vascular study in patients presenting with chronic, nonhealing heel ulcerations. LEVELS OF EVIDENCE Level IV: Diagnostic, Case series.
Collapse
Affiliation(s)
- Valerie S Marmolejo
- University Place, Washington (VSM)
- Great River Wound and Hyperbaric Medicine Clinic, Great River Medical Center, West Burlington, Iowa (JFA)
| | - Jonathan F Arnold
- University Place, Washington (VSM)
- Great River Wound and Hyperbaric Medicine Clinic, Great River Medical Center, West Burlington, Iowa (JFA)
| |
Collapse
|
16
|
Nakamura M, Igari K, Toyofuku T, Kudo T, Inoue Y, Uetake H. The evaluation of contralateral foot circulation after unilateral revascularization procedures using indocyanine green angiography. Sci Rep 2017; 7:16171. [PMID: 29170484 PMCID: PMC5700981 DOI: 10.1038/s41598-017-16527-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 11/13/2017] [Indexed: 11/21/2022] Open
Abstract
The aim of the present study is to assess the effects of unilateral revascularization on the contralateral foot circulation using indocyanine green (ICG). From January 2016 to April 2016, a total of twenty-one patients were included in this study. The patients underwent elective unilateral revascularization at our institution and we evaluated the feet circulation by indocyanine green angiography (ICGA) tests preoperatively and postoperatively. The ICGA parameters included the magnitude of intensity from the onset of ICG to the maximum intensity (Imax), the time from the onset of ICG to the maximum intensity (Tmax), and the time required to reach the half maximum intensity from the onset of ICG (T1/2). There were significant differences in the treated limb Tmax (P = 0.016) and T1/2 (P = 0.013) values and in the contralateral limb Tmax (P = 0.013), and T1/2 (P < 0.001) values on the perioperative ICGA tests. These results reflect the increase in skin perfusion in the treated limb and the decrease in skin perfusion in the contralateral limb. Unilateral revascularization decreases contralateral foot circulation. The preoperative contralateral lesion should be evaluated when revascularization is performed.
Collapse
Affiliation(s)
- Masahiro Nakamura
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
| | - Kimihiro Igari
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Takahiro Toyofuku
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Toshifumi Kudo
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Yoshinori Inoue
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Hiroyuki Uetake
- Department of Surgical Specialties, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| |
Collapse
|
17
|
Li WW, Carter MJ, Mashiach E, Guthrie SD. Vascular assessment of wound healing: a clinical review. Int Wound J 2017; 14:460-469. [PMID: 27374428 PMCID: PMC7950183 DOI: 10.1111/iwj.12622] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 04/28/2016] [Indexed: 12/17/2022] Open
Abstract
Although macrovascular screening of patients with chronic wounds, particularly in the lower extremities, is accepted as part of clinical practice guidelines, microvascular investigation is less commonly used for a variety of reasons. This can be an issue because most patients with macrovascular disease also develop concomitant microvascular dysfunction. Part of the reason for less comprehensive microvascular screening has been the lack of suitable imaging techniques that can quantify microvascular dysfunction in connection with non-healing chronic wounds. This is changing with the introduction of fluorescence microangiography. The objective of this review is to examine macro- and microvascular disease, the strengths and limitations of the approaches used and to highlight the importance of microvascular angiography in the context of wound healing.
Collapse
|
18
|
Microcirculation Evaluated by Intraoperative Fluorescence Angiography after Tibial Bypass Surgery. Ann Vasc Surg 2017; 40:190-197. [DOI: 10.1016/j.avsg.2016.07.084] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/22/2016] [Accepted: 07/06/2016] [Indexed: 01/31/2023]
|
19
|
Abstract
Critical limb ischemia (CLI), the most advanced form of peripheral artery disease, is associated with significant morbidity, mortality, and health care resource utilization. It is also associated with physical, as well as psychosocial, consequences such as amputation and depression. Importantly, after a major amputation, patients are at heightened risk of amputation on the contralateral leg. However, despite the technological advances to manage CLI with minimally invasive technologies, this condition often remains untreated, with significant disparities in revascularization and amputation rates according to race, socioeconomic status, and geographic region. Care remains disparate across medical specialties in this rapidly evolving field. Many challenges persist, including appropriate reimbursement for treating complex patients with difficult anatomy. This paper provides a comprehensive summary that includes diagnostic assessment and analysis, endovascular versus open surgical treatment, regenerative and adjunctive therapies, and other important aspects of CLI.
Collapse
|
20
|
Rundback JH, Armstrong EJ, Contos B, Iida O, Jacobs D, Jaff MR, Matsumoto AH, Mills JL, Montero-Baker M, Pena C, Tallian A, Uematsu M, Wilkins LR, Shishehbor MH. Key Concepts in Critical Limb Ischemia: Selected Proceedings from the 2015 Vascular Interventional Advances Meeting. Ann Vasc Surg 2016; 38:191-205. [PMID: 27569717 DOI: 10.1016/j.avsg.2016.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/01/2016] [Accepted: 08/03/2016] [Indexed: 01/28/2023]
Abstract
Over 500,000 patients each year are diagnosed with critical limb ischemia (CLI), the most severe form of peripheral artery disease. CLI portends a grim prognosis; half the patients die from a cardiovascular cause within 5 years, a rate that is 5 times higher than a matched population without CLI. In 2014, the Centers for Medicare and Medicaid Services paid approximately $3.6 billion for claims submitted by hospitals for inpatient and outpatient care delivered to patients with CLI. Although significant advances in diagnosis, treatment, and follow-up of patients with CLI have been made, many challenges remain. In this article, we summarize selected presentations from the 2015 Vascular Interventional Advances Conference related to the modern demographics, diagnosis, and management of patients with CLI.
Collapse
Affiliation(s)
- John H Rundback
- Interventional Institute, Holy Name Medical Center, Teaneck, NJ.
| | - Ehrin J Armstrong
- Department of Vascular Surgery, VA Eastern Colorado Healthcare System and University of Colorado, Denver, CO
| | | | - Osamu Iida
- Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Japan
| | - Donald Jacobs
- Department of Surgery, Saint Louis University School of Medicine, St. Louis, MO
| | - Michael R Jaff
- Department of Vascular Medicine, Massachusetts General Hospital, Boston, MA
| | - Alan H Matsumoto
- Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, VA
| | - Joseph L Mills
- Division of Vascular Surgery and Endovascular Therapy, Baylor College of Medicine, Houston, TX
| | - Miguel Montero-Baker
- Division of Vascular Surgery and Endovascular Therapy, Baylor College of Medicine, Houston, TX
| | - Constantino Pena
- Miami Cardiac and Vascular Institute, Baptist Hospital of Miami, Miami, FL
| | | | - Masaaki Uematsu
- Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Japan
| | - Luke R Wilkins
- Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, VA
| | - Mehdi H Shishehbor
- Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH
| |
Collapse
|
21
|
Kumagai Y, Ishiguro T, Sobajima J, Fukuchi M, Ishibashi K, Mochiki E, Kawano T, Ishida H. Factors Affecting Blood Flow at the Tip of the Reconstructed Gastric Tube During Esophagectomy: A Study Using Indocyanine Green Fluorescence Angiography. Int Surg 2016; 101:381-389. [DOI: 10.9738/intsurg-d-15-00194.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Abstract
The objective of this study was to clarify the factors affecting blood flow at the tip of the gastric tube during esophagectomy using indocyanine green (ICG) fluorescence angiography. The time until enhancement of the gastric tube tip determined using ICG fluorescence imaging is a useful indicator of blood flow, and has been shown not to differ significantly according to the connection status of the right or left gastroepiploic artery. Using ICG fluorescence imaging, the time until enhancement of the gastric tube tip was measured in 50 patients undergoing esophagectomy. Blood flow at the gastric tube tip was compared between 2 groups of patients: those in whom a connecting vessel from the left gastro-epiploic artery to the short gastric artery (l-s GA) was present and those in whom it was absent. The factors affecting blood flow to the gastric tube tip were also investigated using univariate and multivariate logistic regression analysis. The median time taken for the gastric tube tip to show enhancement with ICG was significantly shorter in the group with an l-s GA connection (P = 0.02). Multivariate analysis showed that the absence of an l-s GA connection (P = 0.04) and presence of arteriosclerosis-related disease (P = 0.02) were significant independent factors that delayed blood flow to the gastric tube. It is essential to preserve the whole vessel arcade of the greater curvature to achieve good perfusion of the gastric tube with blood. The presence of arteriosclerosis-related disease is a major factor affecting the safety of anastomosis during gastric tube reconstruction.
Collapse
Affiliation(s)
- Youichi Kumagai
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Toru Ishiguro
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Jun Sobajima
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Minoru Fukuchi
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Keiichiro Ishibashi
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Erito Mochiki
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Tatsuyuki Kawano
- Department of Surgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hideyuki Ishida
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| |
Collapse
|
22
|
Colvard B, Itoga NK, Hitchner E, Sun Q, Long B, Lee G, Chandra V, Zhou W. SPY technology as an adjunctive measure for lower extremity perfusion. J Vasc Surg 2016; 64:195-201. [PMID: 26994959 DOI: 10.1016/j.jvs.2016.01.039] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 01/23/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Lack of a reliable outcome measure often leads to excessive or insufficient interventions for critical limb ischemia (CLI). SPY technology (Novadaq Technologies Inc, Bonita Springs, Fla), widely adapted by plastic and general surgeons, uses laser-assisted fluorescence angiography (LAFA) to assess tissue perfusion. We sought to determine the role of SPY as an alternative, perhaps more reliable outcome measure for vascular interventions. METHODS All patients undergoing elective or urgent revascularization for claudication and CLI were prospectively recruited from June 2012 to August 2014. LAFA using SPY technology was performed before and after revascularization procedures under a standard Institutional Review Board-approved protocol. Quantitative measures of perfusion at plantar surfaces were analyzed and compared with ankle-brachial index. RESULTS A total of 93 patients with claudication or CLI underwent LAFA before and after a revascularization procedure in the study period. The mean preoperative ankle-brachial index increased from 0.60 to 0.84 (P < .001) after a revascularization procedure. Plantar perfusion as measured by LAFA also improved significantly after intervention. Ingress, defined as the rate at which fluorescence intensity increases on the plantar surface during LAFA, increased from 7.1 to 12.4 units/s (P < .001). Peak perfusion, defined as the difference between the baseline and the peak of fluorescence intensity, increased from 97.1 and 143.9 units (P < .001). Egress, defined as the rate at which intensity diminishes after reaching peak perfusion, increased from 1.0 to 1.9 units/s (P = .035). Procedure-related digital embolization was also observed in several patients despite lack of an angiographic finding. CONCLUSIONS This is the largest prospective study evaluating SPY technology in peripheral vascular interventions. Our study shows that SPY is a valuable tool in visualizing real-time procedural outcomes and providing additionally useful information on regional tissue perfusion. Further investigation is warranted to standardize outpatient use and to determine threshold values that predict wound healing.
Collapse
Affiliation(s)
- Benjamin Colvard
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif
| | - Nathan K Itoga
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif
| | - Elizabeth Hitchner
- Section of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif
| | - Qingfeng Sun
- Department of Vascular Surgery, The First Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Becky Long
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif; Section of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif
| | - George Lee
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif; Section of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif
| | - Venita Chandra
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif
| | - Wei Zhou
- Division of Vascular Surgery, Stanford University, Palo Alto, Calif; Section of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif.
| |
Collapse
|