Daisuke Sagara

Quantitative Lymph Imaging for Assessment of Lymph Function using Indocyanine Green Fluorescence Lymphography

OBJECTIVES A new diagnostic imaging technique that can assess lymph function is needed as a screening test in daily practice. This study assessed the use of indocyanine green (ICG) fluorescence lymphography in subjects without leg oedema. METHODS 0.3ml of ICG (0.5 %) was injected subcutaneously at the dorsum of the foot. Subsequently, the movement of ICG dye from the injection site to the groin was traced by visualizing its fluorescence signal with an infrared light camera. The time for the dye to reach the knee and groin were measured (Transit time to knee: TT(K), Transit time to groin: TT(G)). TT(G) was measured while standing, lying at a supine position, standing with massage, and sitting while using a cycle ergometer exercise at an intensity of 50W at 50rpm in ten healthy volunteers at intervals of 14 days. RESULTS Mean TT(G) during standing was 357+/-289 and 653+/-564 seconds for the right and left legs respectively. Compared to TT(G) in the standing position, all other conditions shortened TT(G). In another seventeen subjects without leg oedema, we compared transit time obtained with ICG fluorescence lymphography to that with dynamic lymphoscintigraphy. A significant correlation between transit time measured with ICG lymphography and dynamic lymphoscintigraphy was identified (r(2)=0.64, p<0.01). CONCLUSIONS ICG fluorescence lymphography has the potential to become an alternative lymphatic imaging technique to assess lymph function.

A novel method of measuring human lymphatic pumping using indocyanine green fluorescence lymphography.

OBJECTIVES Lymph transportation through the body is partly controlled by the intrinsic pumping of lymphatic vessels. Although an understanding of this process is important for medical application, little is currently known because it is difficult to measure. Here, we introduce an easy, safe, and cost-effective technique for measuring lymphatic pumping in leg superficial lymphatic vessels. Readings obtained with this technique were compared with values obtained with dynamic lymphoscintigraphy. Differences in lymphatic pumping between healthy volunteers and patients with lymphedema were also investigated. METHODS Indocyanine green (ICG) fluorescence lymphography was performed by subcutaneously injecting 0.3 mL of ICG (0.5%) into the dorsum of the foot. Real-time fluorescence images of lymph propulsion were obtained with an infrared-light camera system with the individual supine or sitting. A custom-made transparent sphygmomanometer cuff was wrapped around the lower leg and connected to a standard mercury sphygmomanometer. The cuff was inflated to 60 mm Hg and then gradually deflated at 5-minute intervals to lower the pressure by 10-mm Hg steps until the fluorescence contrast agent exceeded the upper border of the cuff, indicating that the lymphatic contraction had overcome the cuff pressure. Lymph pumping pressure (P(pump)) was defined as the value of the cuff pressure when the contrast agent exceeded the upper border of the cuff. We measured P(pump) among healthy volunteers who maintained a supine position and compared these values with measurements obtained from lymphoscintigraphy. P(pump) values while sitting were also compared between 30 legs from healthy volunteers and 30 legs from lymphedematous patients. RESULTS Among healthy, supine participants, P(pump) was 25.2 ± 16.7 mm Hg (mean ± standard deviation [SD]) when measured by ICG fluorescence lymphography. These values were significantly correlated with values taken using dynamic lymphoscintigraphy (r(2) = 0.54, p < .01), while 2 SDs of the mean were approximately 20 mm Hg, suggesting a substantial disagreement between the two methods (Bland-Altman plots). In the comparison of seated measurements, readings for healthy participants (P(pump) = 29.3 ± 16.0) were higher than those for lymphedematous participants (13.2 ± 14.9). CONCLUSION ICG fluorescence is an accurate-as well as a safe, easy, and economical-method of measuring lymphatic pumping. Therefore, it may develop as a vital tool for diagnosing lymphatic malfunctions even when they are only in their formative stages. Studies that use this technique may increase our knowledge of the lymphatic system as a whole, allowing us to develop better treatments for lymphatic disorders.

Imaging Mass Spectrometry Reveals Unique Lipid Distribution in Primary Varicose Veins

BACKGROUND The lipid metabolism of varicose veins (VVs) remains unknown. To elucidate the pathogenesis of VV, we utilized the novel technique of imaging mass spectrometry (IMS). MATERIALS AND METHODS We obtained VV tissues from 10 limbs of 10 VV patients who underwent great saphenous vein stripping. As control vein samples, we harvested segmental vein tissues from 6 limbs of 6 patients with peripheral artery occlusive disease who underwent infra-inguinal bypass with reversed saphenous vein grafting. To identify the localisation of lipid molecules in the VV tissues, we performed matrix-assisted laser desorption/ionization IMS (MALDI-IMS). We also performed MS/MS analyses to identify the structure of each molecule. RESULTS We obtained mass spectra directly from control vein tissues and VV tissues and found a unique localisation of lipid molecules in the VV tissues. We localised lysophosphatidylcholine (LPC) (1-acyl 16:0), phosphatidylcholine (PC) (1-acyl 36:4) and sphingomyelin (SM) (d18:1/16:0) at the site of the VV valve. CONCLUSION MALDI-IMS revealed the distribution of various lipid molecules in normal veins and VVs both. Accumulation of LPC (1-acyl 16:0), PC (1-acyl 36:4) and SM (d18:1/16:0) in the VV tissues suggested that inflammation associated with abnormal lipid metabolism may contribute to the development of VV.

Impaired lymphatic function recovered after great saphenous vein stripping in patients with varicose vein: Venodynamic and lymphodynamic results

OBJECTIVES Venodynamics and lymphodynamics may interact as an inseparable and mutually dependent dual outflow system. This study investigated the effect of surgical treatment on lower limb lymph flow in patients with varicose veins. METHODS Thirty-nine patients with varicose veins in the lower limb (28 patients with unilateral limb, 11 patients with bilateral limb), who demonstrated great saphenous vein reflux, were investigated with air-plethysmography and indocyanine green (ICG) fluorescence lymphography before surgical treatment and 6 months later. Fifteen healthy volunteers participated in this study as a control. With air-plethysmography, venous volume (VV) and venous filling time were measured. Venous filling index (VFI) was calculated. For ICG lymphography, 0.3 mL of ICG (0.5%) was subcutaneously injected at the dorsum of the foot. After the injection, fluorescent image of ICG dye was traced on real-time video images using a near-infrared camera system. The interval until the dye reached the knee was measured (transit time [TT]) in a standing position, which was previously demonstrated to correlate with the interval measured using dynamic isotope lymphoscintigraphy. RESULTS In CEAP clinical stage venous disease, TT in patients with C4 approximately 6 and C2 approximately 3 was significantly longer than that in the control group (587 +/- 97 seconds, 484 +/- 82 seconds, 252 +/- 29 seconds, respectively, mean +/- SD, P < .01). Among all limbs with varicose veins, there were correlations between TT and VV (Pearson r = 0.31, P < .01), between TT and VFI (Pearson r = 0.48, P < .01). All patients underwent great saphenous vein stripping. Six months later, the venous clinical severity score significantly improved with significant reductions in both VV and VFI values. TT 6 months postoperatively was also significantly shorter than that before surgical treatment (501 +/- 67 seconds, 340 +/- 38 seconds, respectively, mean +/- SD, P < .01). CONCLUSIONS Varicose veins could affect lymphatic function and delay lymphatic flow in the lower limbs. Derangement of lymph flow may correlate with the severity of clinical venous disease and/or the magnitude of venous reflux, which could be reversible with surgical treatment of venous incompetence.

Bile leak test by indocyanine green fluorescence images after hepatectomy

Bile leak remains a serious complication after hepatectomy. The conventional leak test by intrabiliary injection of normal saline solution is not sensitive. The authors present a new bile leak test using indocyanine green (ICG) fluorescence. After hepatic transection, ICG solution (.05 mg/mL) was intrabiliarily injected through a transcystic tube under distal common bile duct clamping, and fluorescent images were visualized using an infrared camera system. The ICG leak test was performed in 27 patients undergoing hepatectomy without biliary reconstruction. Bile leaks were intraoperatively found in 8 patients and fixed, resulting in no postoperative leaks. There was no adverse reaction to ICG. In contrast, postoperative bile leaks occurred in 2 of 32 patients who received the conventional leak test with normal saline solution between April 2007 and March 2008. The new bile leak test by ICG fluorography is useful to prevent postoperative bile leak.

Laparoscopic Nephrectomy, Ex Vivo Repair, and Autotransplantation for a Renal Artery Aneurysm : Report of a Case

A 57-year-old woman was hospitalized with a left renal artery aneurysm (RAA). The aneurysm measured 35 mm in diameter and was located at the renal artery bifurcation. We performed a laparoscopic nephrectomy using a retroperitoneal approach and performed an ex vivo repair of the renal artery. The reconstructed kidney was then autotransplanted at the left iliac fossa. The patients postoperative course was uneventful. A laparoscopic nephrectomy and ex vivo repair are both considered to be effective for treating complex RAA.

Hemorrhagic Shock with Delayed Retroperitoneal Hemorrhage After Deployment of an Inferior Vena Cava Filter: Report of a Case

Although inferior vena cava (IVC) filter placement has demonstrated an excellent therapeutic efficacy in preventing pulmonary embolism, several filter-related complications have been reported. Among them, retroperitoneal hemorrhage due to IVC perforation is one of the most serious complications. We report herein a female patient who underwent TrapEase IVC filter placement with anticoagulation and thrombolytic therapy for treatment of pulmonary embolism, and later demonstrated hemorrhagic shock 5 days after filter placement. The patients blood pressure stabilized after the anticoagulant therapy was stopped and she received a blood transfusion. We should therefore carefully observe patients after IVC filter placement, particularly those receiving simultaneous anticoagulation therapy.

Intraperitoneal administration of hyperbarically oxygenated perfluorochemical enhances preservation of intestinal mucosa against ischemia/reperfusion injury.

ABSTRACT Perfluorochemicals (PFCs) have a high solubility for oxygen. We have previously demonstrated the effect of peritoneal lavage with oxygenated PFC (O2-PFC) on ameliorating ischemia/reperfusion (I/R)-induced intestinal ischemic damage in an animal model. In this study, we applied hyperbarically O2-PFC (HBO-PFC) to investigate whether a larger amount of oxygen carried by PFC could enhance the protective effect of O2-PFC during intestinal malperfusion. Rats were subjected to ischemia by clamping the superior mesenteric artery (SMA) for 90 min. The SMA was then declamped. Rats were divided into four groups. In group A, only anesthesia and abdominal incision were performed. In group B, SMA was clamped without O2-PFC. In group C, during the SMA clamp, 1 atm O2-PFC was injected into the abdominal cavity. In group D, 5 atm O2-PFC (HBO-PFC) was prepared using a custom-made hyperbaric oxygen tank and administered to the abdominal cavity during the SMA clamp. Ileal tissue adenosine triphosphate (ATP) levels 90 min after SMA declamping were determined using luciferase assay. To assess intestinal mucosal barrier function at 90 min after release of the SMA clip, everted gut sacs were prepared to measure the mucosal-to-serosal passage of fluorescein-conjugated dextran (FD4, molecular weight = 4 kDa). Thirty minutes after i.p. administraton, partial pressure of oxygen in HBO-PFC remained around 1000 mmHg, whereas partial pressure of oxygen in 1 atm O2-PFC decreased to around 400 mmHg. The intestinal tissue ATP was significantly preserved in group D. Moreover, the mucosal hyperpermeability of the gut sac after I/R was significantly ameliorated in group D. Hyperbarically oxygenated perfluorochemical might supply a larger amount of oxygen to ischemic tissue during SMA clamp, which protected the small intestine from I/R injury, possibly caused by the maintenance of tissue ATP levels during ischemia.

Automated Bedside Measurement of Penile Blood Flow Using Pulse-Volume Plethysmography

PurposeTo evaluate the efficiency of the form PWV/ABI (pulse wave velocity/ankle brachial pressure index) for measuring penile blood pressure (PBP) and the penile brachial pressure index (PBI).MethodsWe measured PBP and the PBI using both form PWV/ABI and Doppler ultrasonography in 40 men with surgical disorders.ResultsBy using pulse-volume recording, the form PWV/ABI can simultaneously measure PBP and bilateral brachial artery pressure, and calculate the PBI automatically. The data obtained showed strong correlations with those obtained by the conventional Doppler ultrasound technique. Moreover, measurements were completed within 5 min at the bedside and the data were stored in the devices memory.ConclusionThe form PWV/ABI is a useful tool for assessing pelvic hemodynamics and diagnosing vasculogenic impotence.

Two-stage Surgery for Endovascular Repair and Laparoscopic Colectomy for a Patient with Abdominal Aortic Aneurysm and Concomitant Colon Cancer: Report of a Case

Surgical management of abdominal aortic aneurysm (AAA) with concomitant malignancy remains controversial. Commercial availability of a stentgraft may change the treatment strategy for such patients. We present a case of AAA with concomitant colon cancer, in which two-stage surgery consisting of EVAR and subsequent laparoscopic colectomy was performed with an interval of six days. The patients postoperative course was uneventful. For high-risk patients, application of endovascular AAA repair and laparoscopic surgery may decrease the risk of surgical morbidity and mortality.