Therapeutic coil embolization of dominant shunt in hepatopulmonary syndrome enhances post-liver transplant respiratory recovery.

Coil embolization of the atypical enlarged pulmonary artery/arteriole with visible shunting may improve hypoxemia in patients with hepatopulmonary syndrome (HPS). When used selectively in cases with large shunts, either pre- or post-liver transplantation (LT), it can aid an early recovery and reduce morbidity. We present a case where a large intrapulmonary shunt was embolized preoperatively to improve hypoxemia associated with HPS and enhance post-operative recovery.

Onco-reconstructive supermicrosurgery.

Supermicrosurgery is sophisticated microsurgical technique, which allows dissection and anastomosis of blood/lymphatic vessels and nerves with external diameter of 0.5 mm or smaller. With increasing attention to quality of life of cancer survivors, less invasive and functionally-better oncological reconstruction using supermicrosurgical techniques is warranted. Unlike conventional free flap reconstruction, supermicrosurgical free flaps can be elevated from anywhere using innominate vessels with diameter of 0.1 mm or larger, allowing patient-oriented least invasive reconstruction. Since lymphatic vessels can be anastomosed, lymphatic reconstruction is possible with supermicrosurgery, which plays an important role in management of cancer-related lymphedema. Supermicrosurgeons can harvest vascularized tissues such as skin, fat, fascia, tendon, ligament, bone, muscle, and nerve separately, and reconstruct complicated defects with three-dimensionally-inset multi-component tissue transfer.

Aspirin treatment does not increase microhemorrhage size in young or aged mice.

Microhemorrhages are common in the aging brain and are thought to contribute to cognitive decline and the development of neurodegenerative diseases, such as Alzheimer's disease. Chronic aspirin therapy is widespread in older individuals and decreases the risk of coronary artery occlusions and stroke. There remains a concern that such aspirin usage may prolong bleeding after a vessel rupture in the brain, leading to larger bleeds that cause more damage to the surrounding tissue. Here, we aimed to understand the influence of aspirin usage on the size of cortical microhemorrhages and explored the impact of age. We used femtosecond laser ablation to rupture arterioles in the cortex of both young (2-5 months old) and aged (18-29 months old) mice dosed on aspirin in their drinking water and measured the extent of penetration of both red blood cells and blood plasma into the surrounding tissue. We found no difference in microhemorrhage size for both young and aged mice dosed on aspirin, as compared to controls (hematoma diameter = 104 +/- 39 (97 +/- 38) µm in controls and 109 +/- 25 (101 +/- 28) µm in aspirin-treated young (aged) mice; mean +/- SD). In contrast, young mice treated with intravenous heparin had an increased hematoma diameter of 136 +/- 44 µm. These data suggest that aspirin does not increase the size of microhemorrhages, supporting the safety of aspirin usage.

Pseudoaneurysm associated with arteriovenous fistula involving a superficial breast arteriole after vacuum-assisted removal of a benign mass: A case report.

RATIONALE: Pseudoaneurysm (PA) with associated arteriovenous fistula (AVF) is most often secondary to vascular catheterization, percutaneous biopsy, surgery, or trauma. PA-AVF occurs mainly in large or median arterial territories but rarely in the superficial arterioles of the breast. PATIENT CONCERNS: A 30-year-old woman underwent vacuum-assisted removal of breast fibroadenomas under ultrasonic guidance. On the follow-up visit, the patient complained of a painful enlarging lump in her left breast. DIAGNOSES: An iatrogenic breast PA-AVF was diagnosed. INTERVENTIONS: The patient was treated with surgical excision and ligation under local anesthesia. OUTCOMES: At the 1-month follow-up, the wound was found to have healed well, and breast PA-AVF was eradicated. LESSONS: Vacuum-assisted removal has been the first-line intervention for benign mass resection because of minimal invasion, but the risk of serious vascular complications remains. Careful duplex ultrasound examination prior to the procedure is highly recommended.

Enhanced coronary arteriolar contraction to vasopressin in patients with diabetes after cardiac surgery.

OBJECTIVE: Cardioplegic arrest (CP) and cardiopulmonary bypass (CPB) are associated with vasomotor dysfunction of coronary arterioles in patients with diabetes (DM) undergoing cardiac surgery. We hypothesized that DM may up-regulate vasopressin receptor expression and alter the contractile response of coronary arterioles to vasopressin in the setting of CP/CPB. METHODS: Right atrial tissue samples of patients with DM and without (ND) (n = 8 in each group) undergoing cardiac surgery were harvested before and after CP/CPB. The isolated coronary arterioles (80-150 µm) dissected from the harvested right atrial tissue samples were cannulated and pressurized (40 mm Hg) in a no-flow state. The changes in diameter were measured with video microscopy. The protein expression/localization of vasopressin 1A receptors (V1A) and vasopressin 1B receptors (V1B) in the atrial tissue were measured by immune-blotting and immunohistochemistry. RESULTS: The pre-CP/CPB contractile responses of the coronary arterioles to vasopressin were significantly increased post-CP/CPB in both the ND and DM groups. This effect was more pronounced in the vessels from patients in the DM group than that of vessels from patients in the ND group (P < .05). Vasopressin-induced contractile response of the coronary arterioles was inhibited in the presence of the specific V1A antagonist SR 49059 (10-7 M) in both ND and DM vessels (P < .05). The post-CP/CPB protein levels of V1A were significantly increased compared with pre-CP/CPB values in both the ND and DM groups (P < .05), whereas this increase was greater in DM than that of ND (P < .05). Immunohistochemistry staining further indicates that V1B were mainly expressed in the myocardium but not in vascular smooth muscle. CONCLUSIONS: CP/CPB and DM are both associated with up-regulation in V1 receptor expression/localization in human myocardium. Vasopressin may induce coronary arteriolar constriction via V1A. This alteration may lead to increased coronary arteriolar spasm in patients with DM undergoing CP/CPB and cardiac surgery.

Isolation and Cannulation of Cerebral Parenchymal Arterioles.

Intracerebral parenchymal arterioles (PAs), which include parenchymal arterioles, penetrating arterioles and pre-capillary arterioles, are high resistance blood vessels branching out from pial arteries and arterioles and diving into the brain parenchyma. Individual PA perfuse a discrete cylindrical territory of the parenchyma and the neurons contained within. These arterioles are a central player in the regulation of cerebral blood flow both globally (cerebrovascular autoregulation) and locally (functional hyperemia). PAs are part of the neurovascular unit, a structure that matches regional blood flow to metabolic activity within the brain and also includes neurons, interneurons, and astrocytes. Perfusion through PAs is directly linked to the activity of neurons in that particular territory and increases in neuronal metabolism lead to an augmentation in local perfusion caused by dilation of the feed PA. Regulation of PAs differs from that of better-characterized pial arteries. Pressure-induced vasoconstriction is greater in PAs and vasodilatory mechanisms vary. In addition, PAs do not receive extrinsic innervation from perivascular nerves - innervation is intrinsic and indirect in nature through contact with astrocytic endfeet. Thus, data regarding contractile regulation accumulated by studies using pial arteries does not directly translate to understanding PA function. Further, it remains undetermined how pathological states, such as hypertension and diabetes, affect PA structure and reactivity. This knowledge gap is in part a consequence of the technical difficulties pertaining to PA isolation and cannulation. In this manuscript we present a protocol for isolation and cannulation of rodent PAs. Further, we show examples of experiments that can be performed with these arterioles, including agonist-induced constriction and myogenic reactivity. Although the focus of this manuscript is on PA cannulation and pressure myography, isolated PAs can also be used for biochemical, biophysical, molecular, and imaging studies.

Clinical Application of an Original Vascular Anastomosis: A Clinical Multicenter Study.

PURPOSE: Vascular anastomosis is the most important technical step required for the possibility of free tissue transfer, and mismatch of the donor and recipient vessel size is the most common surgical challenge. As recent reports have described a new method (Ren anastomosis) to resolve this challenge, the goal of this study was to assess these newly described microvascular anastomosis methods. PATIENTS AND METHODS: The study was conducted at 2 institutes in China in different periods. Patients were recruited from the Second Xiangya Hospital between February and May 2013 and from the Shanghai Ninth People's Hospital between March and May 2015. All patients who participated in this study needed free flaps for oral and maxillofacial defects. Patients were divided into the experimental group and the control group. In the experimental group, isometric double-notch end-in-end microvascular anastomosis (Ren anastomosis) was performed, whereas end-to-end anastomosis was performed in the control group. Statistical differences were assessed by use of χ2 and t tests. RESULTS: A total of 148 patients (108 men and 40 women) were treated over the course of this study. There was a statistically significant difference (P < .001) in the operation time for the microscopic artery anastomosis between the experimental group (70 cases; 5.6 ± 1.8 minutes) and the control group (78 cases; 14.6 ± 3.7 minutes). In each group, 1 case of artery compromise was observed. CONCLUSIONS: The Ren anastomosis was time-saving, straightforward, efficient, and easy to learn, with a high patency rate.

Intravitreal bevacizumab and feeder vessel laser treatment for a posteriorly located retinal capillary hemangioma.

Retinal capillary hemangioma (RCH) is strongly associated with von Hippel-Lindau (VHL) disease. Treatment of this sight-threatening condition is often unsatisfactory despite multiple treatment options available. We here describe an interesting case of a 50-year-old male with RCH located in the perifoveal region of the left eye. Subretinal bleed, exudation, and macular edema resulted in progressive deterioration of visual acuity. Fundus photography, fluorescein angiography, and optical coherence tomography (OCT) were used to serially monitor the lesion. After ruling out systemic lesions of VHL disease, the patient was subjected to direct laser photocoagulation of the lesion which resulted in further loss in vision with increase in bleed and exudation. Subsequently, the patient was given 2 monthly intravitreal injections of bevacizumab followed by laser photocoagulation of feeder arteriole. This combination therapy resulted in resolution of exudation, bleed, and macular edema with improvement in visual acuity. Thus, vision-threatening RCH may be safely and effectively treated by means of a combination therapy comprising of intravitreal bevacizumab and feeder vessel treatment.

The efficiency of endoclips in maintaining the gastrointestinal bleeding-related Dieulafoy's lesion.

BACKGROUND: Dieulafoy's lesion (DL) is a relatively uncommon medical condition characterized by a large tortuous arteriole in the submucosa of any part of gastrointestinal (GI) tract wall that bleeds via erosion likely caused in the submucosal surface by protrusion of the pulsatile arteriole. Compared with other endoscopic hemostatic techniques, clipping alone for DL is limited. AIMS: The aim of the present case series study is to identify common clinical and endoscopic features, rates of occurrence, to review the outcome of endoscopic management of upper GI tract DL, and to illustrate the use and the efficiency of endoclips in maintaining the GI bleeding due to DL. PATIENTS AND METHODS: This case series was conducted at Department of Gastroenterology, Diskapi Yildirim Beyazit Educational and Research Hospital. The patients who were admitted to the emergency department of Diskapi Yildirim Beyazit Educational and Research Hospital underwent gastrointestinal system (GIS) endoscopy between 2008 and 2013 and were assessed retrospectively. Five cases of GI bleeding related to DL were given endoscopic treatment with hemoclip application. Clinical data, endoscopic findings, and the effects of the therapy were evaluated. RESULTS: The median number of endoscopic hemoclips application in first endoscopy was 4 (2-9). Rebleeding developed in all patients who had hemoclips applied. Re-endoscopy was performed in three of these patients, which controlled the bleeding. Two patients were transferred to surgery. CONCLUSIONS: Combination of endoscopic injection and mechanical therapies seems a suitable method for maintaining upper GIS bleeding due to DL. Also, further studies are needed to better define the best endoscopic approach for the treatment of DL.

Pial microvascular responses induced by transient bilateral common carotid artery occlusion in Zucker rats.

This study was aimed to assess the in vivo geometric and functional characteristics of lean Zucker (ZL) and obese Zucker rat (ZO) pial microvascular networks and to evaluate the vascular responses to cerebral hypoperfusion-reperfusion. Rat pial microcirculation was observed by fluorescence microscopy through a closed cranial window. Bilateral common carotid artery occlusion (BCCAO) lasted 30 min and reperfusion 60 min. Arterioles were classified according to Strahler's ordering scheme. Arteriolar diameter was determined by computer assisted-method as well as permeability increase, leukocyte adhesion and perfused capillary length. Neuronal damage was evaluated by TTC staining. ZO rats did not show order 5 vessels; ZO pial arterioles showed high asymmetry in the largest vessels and reduced number of branchings compared with those detected in ZL and Wistar rats. BCCAO and reperfusion caused more severe microvascular damages in ZO compared with ZL and Wistar rats. Vascular responses to acetylcholine and papaverine in ZO rats were significantly reduced compared with Wistar and ZL rats under baseline condition and at the end of reperfusion. Moreover, ZO rats showed more pronounced lesion in the cortex and striatum. Obesity and hyperglycemia could increase vascular remodeling in cerebral networks, with elevated risk of adverse outcome after brain hypoperfusion-reperfusion.

Murine spinotrapezius model to assess the impact of arteriolar ligation on microvascular function and remodeling.

The murine spinotrapezius is a thin, superficial skeletal support muscle that extends from T3 to L4, and is easily accessible via dorsal skin incision. Its unique anatomy makes the spinotrapezius useful for investigation of ischemic injury and subsequent microvascular remodeling. Here, we demonstrate an arteriolar ligation model in the murine spinotrapezius muscle that was developed by our research team and previously published(1-3). For certain vulnerable mouse strains, such as the Balb/c mouse, this ligation surgery reliably creates skeletal muscle ischemia and serves as a platform for investigating therapies that stimulate revascularization. Methods of assessment are also demonstrated, including the use of intravital and confocal microscopy. The spinotrapezius is well suited to such imaging studies due to its accessibility (superficial dorsal anatomy) and relative thinness (60-200 µm). The spinotrapezius muscle can be mounted en face, facilitating imaging of whole-muscle microvascular networks without histological sectioning. We describe the use of intravital microscopy to acquire metrics following a functional vasodilation procedure; specifically, the increase in arterilar diameter as a result of muscle contraction. We also demonstrate the procedures for harvesting and fixing the tissues, a necessary precursor to immunostaining studies and the use of confocal microscopy.

A clinical analysis on microvascular decompression surgery in a series of 3000 cases.

OBJECTIVE: Despite the microvascular decompression (MVD) has become a definitive treatment for trigeminal neuralgia (TN) and hemifacial spasm (HFS), not all of the patients have been cured completely so far and this sort of operation is still with risk because of the critical operative area. In order to refine this surgery, we investigated thousands MVDs. METHODS: Among 3000 consecutive cases of MVDs have been performed in our department, 2601 were those with typical TN or HFS, who were then enrolled in this investigation. They were retrospectively analyzed with emphasis on the correlation between surgical findings and postoperative outcomes. The differences between TN and HFS cases were compared. The strategy of each surgical process of MVD was addressed. RESULTS: Postoperatively, the pain free or spasm cease occurred immediately in 88.3%. The symptoms improved at some degree in 7.2%. The symptoms unimproved at all in 4.5%. Most of those with poor outcome underwent a redo MVD in the following days. Eventually, their symptoms were then improved in 98.7% of the reoperative patients. The majority reason of the failed surgery was that the neurovascular conflict located beyond REZ or the offending veins were missed for TN, while the exact offending artery (arteriole) was missed for HFS as it located far more medially than expected. CONCLUSION: A prompt recognition of the conflict site leads to a successful MVD. To facilitate the approach, the craniotomy should be lateral enough to the sigmoid sinus. The whole intracranial nerve root should be examined and veins or arterioles should not be ignored. For TN, all the vessels contacting the nerve should be detached. For HFS, the exposure should be medial enough to the pontomedullary sulcus.

Anti-thrombotic effects of selective estrogen receptor modulator tamoxifen.

Tamoxifen is a known anti-cancer drug and established estrogen receptor modulator. Few clinical studies have earlier implicated the drug in thrombotic complications attributable to lower anti-thrombin and protein S levels in plasma. However, action of tamoxifen on platelet signalling machinery has not been elucidated in detail. In the present report we show that tamoxifen is endowed with significant inhibitory property against human platelet aggregation. From a series of in vivo and in vitro studies tamoxifen was found to inhibit almost all platelet functions, prolong tail bleeding time in mouse and profoundly prevent thrombus formation at injured arterial wall in mice, as well as on collagen matrix perfused with platelet-rich plasma under arterial shear against the vehicle dimethylsulfoxide (DMSO). These findings strongly suggest that tamoxifen significantly downregulates platelet responses and holds potential as a promising anti-platelet/anti-thrombotic agent.

Preventing negative effects of smoking on microarterial anastomosis.

Although microsurgery has rapid expanded, problems related to microarterial anastomosis continue. Cigarette smoking is one of the major risks for anastomosis by increasing platelet adhesion, and its effects on endothelial cells. Aim of this article is to study the negative effects of cigarettes on microarterial anastomosis line, and to investigate the protective effects of recombinant human erythropoietin (rHuEPO).Ninety-six Sprague-Dawley male rats were divided into 3 groups: group 1 was the control. Rats in groups 2 and 3 were exposed to cigarette smoke starting 21 days prior to surgery for 3 times a day. In group 3, additional 150 IU/kg rHuEPO was given via subcutaneously every 48 hours after microvascular anastomosis, femoral arterial samples, and blood samples were taken for assessment at 1st, 3rd, 5th, and 7th day. Intimae/media ratios were calculated for morphologic analyses.On morphologic analysis of femoral arteries there were statistically significant differences for all 3 groups at 1st, 3rd, 5th, and 7th days (P < 0, 05). The group that made differences was group 2, according to one-way analysis of variance within 3 groups in all days.Smoking decreases endothelial cells healing and causes more thromboses. rHuEPO can prevent these negative effects of smoking.

Arterial reconstruction in a case of subintimal dissection of celiac arterial tributaries in living donor liver transplantation: a case report.

BACKGROUND: Hepatic arterial reconstruction is one of the critical issues in living donor liver transplantation (LDLT). Herein we have reported an LDLT case whose celiac arterial trunk tributaries were insufficient as host arteries because of extensive subintimal dissection proceeding to all tributaries of the celiac arterial trunk. PATIENTS AND METHODS: A 45-year-old woman with fulminant hepatic failure underwent LDLT. After reperfusion of the hepatic and portal veins, subintimal dissection of the recipient right and left hepatic arteries was found to extend to all tributaries of the celiac arterial trunk, preventing an anastomosis using the more proximal part of these arteries. Therefore, a jejunal arterial arcade of Roux-en-Y limb mobilized for biliary reconstruction was anastomosed to the donor left hepatic artery in end-to-end fashion. RESULTS: Arterial blood flow to the grafted liver was established successfully, and the patient's postoperative recovery was excellent. Postoperative computed tomography demonstrated sufficient hepatic arterial blood flow. The patient is doing well 4 years after transplantation. CONCLUSION: The method of hepatic graft arterialization described herein is an important option for LDLT recipients when tributaries of the celiac arterial trunk are insufficient as host arteries.

[From plastic surgery to space conquest. First microsurgical procedure and first surgical procedure in man during weightlessness]. / De la chirurgie plastique à la conquête spatiale. Première microchirurgie et première opération chez l'homme faites en apesanteur.

The authors present their experience of surgery in weightlessness conditions. Russians and Americans already focused on that subject but two questions were still unsolved: what was the limit of human skill in these extreme conditions and was it possible to operate a human under total safety? Between 2003 and 2007, using a 0G plane for our experiment, we focused on two goals: firstly, the conception of a microsurgical module to test complex microsurgical procedures in rats and secondly, the construction of a surgical workstation with specific air filtration device and define surgical and anaesthetic protocols to carry on a surgery in man. In September 2003, we succeeded to perform the microscopic report of a 0,5mm artery (which is the smallest we can suture in terrestrial conditions) by using seven stitches of 10 x 0 monofilament suture. The 27th of September 2007, we removed a lipoma from the forearm of a 47-year-old man. These experiments take place in a wide program of development of telesurgery controlled through satellite transmission with all forthcoming civil, military and humanitarian applications.

Dynamic indocyanine green angiography-guided focal thermal laser treatment of fibrotic choroidal neovascularization.

PURPOSE: Fibrotic choroidal neovascular membranes (CNV) are the end-stage outcomes of neovascular age-related macular degeneration (AMD). No treatment is currently available for fibrotic CNV. We investigated the role of focal thermal laser ablation of the perfusing afferent arteriole as determined by dynamic indocyanine green angiography (ICGA). METHODS: We conducted a retrospective study of 20 patients with fibrotic CNV associated with significant subretinal fluid or retinal edema, who also demonstrated well-defined perfusing arterioles by dynamic ICGA. Patients underwent focal thermal laser occlusion of the perfusing afferent arteriole. Six, 12 and 24 weeks post-treatment, eyes underwent repeat examination with optical coherence tomography (OCT) and visual acuity testing, and ICGA at 12 weeks. RESULTS: Therapeutic closure of the perfusing afferent arterioles was achieved in 17 of 20 eyes immediately post-treatment. All 17 of these eyes demonstrated significant resolution of retinal edema and subretinal fluid, as evidenced by OCT, which was dramatic in some cases. Seven eyes demonstrated an improvement in visual acuity of 1 line or more. While most eyes demonstrated reperfusion within 3 months, many lesions suggested reduced vascularity and flow. CONCLUSION: Eyes with fibrotic CNV and associated retinal edema often demonstrate well-defined vascularity of the fibrosis with discrete perfusing arterioles when imaged by dynamic ICGA. Thermal laser occlusion of these arterioles can result in resolution of subretinal fluid, and occasionally an improvement in vision. This represents a potential therapeutic intervention for an advanced stage of AMD currently regarded as stable.