Surgical Recanalization Research Articles

Cerebral perfusion changes in patients with internal carotid artery stenoses after surgical revascularization

Changes of cerebral perfusion and the condition of collateral blood supply in patients with internal carotid artery stenoses may have a prognostic value for effective blood flow restoration after revascularization of the internal carotid arteries (ICAs). To determine the patterns of cerebral perfusion changes in patients with ICA stenoses before and after surgical treatment, a clinical CT perfusion study of 41 patients with moderate to severe ICA stenoses was performed. Perfusion CT (PCT) had been conducted in 17 patients with moderate ICA stenoses (50–69%) and in 24 patients with severe ICA stenoses (70–99%) 3 times: before intervention (balloon angioplasty with stenting or carotid endarterectomy), on the 3rd to 7th day, and within 1 to 3 months after surgery. Scanning was performed at the level of the basal ganglia and semioval centers. In patients without ICA stenosis (control group of 39 individuals), PCT was conducted once. We found that surgical recanalization of the ICA leads to normalization of the cerebral blood flow parameters in the perfusion area of the middle cranial artery, as evidenced by a decrease of MTT and CBV and an increase of CBF to values comparable to those in the control group. However, blood flow restoration in the anterior and posterior watershed areas, which are known to be mostly affected under chronic hypoperfusion conditions, was observed only in patients with a complete circle of Willis (CW) and moderate ICA stenosis. Therefore, severe stenosis (>70%) and the incomplete CW are the prognostic factors for inadequate blood flow restoration after revascularization in patients with ICA stenoses.

Image-Guided Sharp Recanalization of a Benign J Pouch Anastomotic Occlusion Facilitates Surgical Repair

A 27-year-old man with a 9-year history of ulcerative colitis who had undergone total proctocolectomy with construction of a continent pouch in 2008 presented 1 year later with occlusion of the ileal pouch–anal anastomosis precluding ileostomy closure. An attempt at surgical reconstruction at an outside hospital failed, and the patient was informed that he would have a permanent stoma. A further attempt at blind surgical recanalization of the occlusion risked sphincter damage and was deferred. In 2010, reconstruction was performed using a hybrid approach combining image-guided sharp recanalization of the occluded anastomosis with positioning of a large-diameter Foley balloon catheter across the recanalized segment, followed by immediate surgical revision of the J pouch. Ileostomy closure was performed 1 month later. Continence was preserved. Surgical repair preceded by sharp recanalization with positioning of a balloon catheter across the occluding membrane may safely regain durable patency in a chronically occluded ileal pouch–anal anastomosis.

Acute extracranial occlusion of the internal carotid artery: emergent surgery remains a viable option

Acute symptomatic occlusion of extracranial internal carotid artery (eICA) can lead to a critical and potentially devastating stroke associated with high morbidity and mortality. Optimal treatment remains unclear. We analyzed our institutional experience with emergent surgical recanalization of acutely occluded eICA. Retrospective analysis of hospital records, surgical reports, imaging studies and outpatient records. Final outcome was assessed according to modified Rankin Scale (mRS). Between January 2010 and September 2013, 22 patients underwent emergent surgical recanalization. There were 17 men and five women, mean age 65.4years (range 37-85). Mean admission National Institute of Health Stroke Scale (NIHSS) was 12 (range 6-21). All patients had evidence of salvageable penumbra on perfusion computed tomography. Tandem intracranial lesion was present in nine patients. Surgical recanalization was successful in 16 patients (72.7%). Twenty-four hours after surgery, 17 patients (77.2%) improved by a minimum of 1 point on NIHSS, 14 patients (63.6%) improved by three and more points; two patients deteriorated by two and five points, the latter treated initially with systemic thrombolysis due to intracranial hemorrhage. No other intracranial hematoma was observed. During 30days following surgery, two patients died (9% mortality rate) due to severity of initial stroke. On discharge, four patients were classified as mRS 0, five patients as mRS 1, five patients as mRS 2 and six patients as mRS 4. Favorable recovery (mRS 0-2) was achieved in 14 patients (63.6%). No change in mRS was observed at threemonths. Our results suggest that emergent surgical desobliteration of occluded eICA can lead to favorable recovery in a majority of patients. Patient selection based on penumbra imaging is crucial. Given the popularity and simplicity of carotid endarterectomy, the procedure should by no means be abandoned in the treatment of acute eICA occlusion.

Cerebral perfusion changes in patients with carotid artery stenosis after surgical revascularization

Assessment of cerebral perfusion and collateral circulation in patients with carotid stenosis might have prognostic value for effective blood flow restoration after carotid revascularization. To evaluate the changes of cerebral perfusion we studied 41 patients with moderate and severe carotid stenosis before and after surgical or endovascular treatment. Perfusion CT at the level of basal ganglia was performed in 17 patients with moderate (50–69%) and 24 patients with severe (70–99%) carotid stenosis for 3 times: before intervention (transluminal angioplasty with stenting or carotid endarterectomy), 3 to 7 days and 1 to 3 months after treatment. Additionally, single CT perfusion study was done in 39 patients without carotid stenosis (control group). We found that surgical recanalization of internal carotid artery may aid restoring cerebral blood flow characteristics in the MCA area to the levels similar to those in control group (namely, decrease of MTT and CBV and increase of CBF). However, in anterior and posterior watershed zones, which are known to be the most vulnerable by chronic hypoperfusion, blood flow normalization was seen only in patients with complete circle of Willis and with moderate carotid stenosis.Thus, prognostic factors for inadequate blood flow restoration in patients with carotid artery stenosis after revascularization include severe stenosis (>70%) and incomplete circle of Willis.

Renaissance of Surgical Recanalization for Proximal Fallopian Tubal Occlusion: Falloposcopic Tuboplasty as a Promising Therapeutic Option in Tubal Infertility

Study Objective To assess the clinical effectiveness of falloposcopic tuboplasty in tubal infertility. Design Retrospective cohort study (Canadian Task Force classification II-3). Setting Infertility clinic. Patients Three hundred forty-five infertile patients (≥2y) with a diagnosis of proximal tubal occlusion, either bilateral or unilateral, between January 2005 and January 2011. Intervention Falloposcopic tuboplasty. Measurements and Main Results Medical records for 345 patients with a diagnosis of proximal tubal occlusion were reviewed. Of the 345 patients, 304 underwent falloposcopic tuboplasty, with successful recanalization achieved in 248 patients (81.6%). Ninety-one of the 304 patients (29.9%) became pregnant. Of these, 18 patients (19.8%) miscarried, and 4 (4.4%) had ectopic pregnancies in the recanalized tube. At 1-, 3-, 6-, and 9-month follow-up, the cumulative probability of conception was 23.1%, 50.6%, 73.6%, and 82.4%, respectively. Related complications included postsurgical infection (0.3%), perforation of the fallopian tube (1.3%), and accidental breakage of the catheter (4.9%) or the falloposcope (1.3%). Conclusions Falloposcopic tuboplasty is safe and effective for treatment of tubal infertility. The pregnancy rate after falloposcopic tuboplasty is comparable to that after in vitro fertilization, which suggests that it can be an alternative to in vitro fertilization in women with tubal infertility.

The Role of Surgical Therapy for Pulmonary Vein Atresia in Childhood

The outcome for children with pulmonary vein atresia has been historically poor. This report describes clinical outcomes after surgical treatment of primary and secondary pulmonary vein atresia. All patients undergoing surgery for pulmonary vein atresia at Children's Hospital Boston from 1 January 2005 to 1 January 2009 were identified. The data available for analysis included demographic characteristics, findings based on cardiac catheterization and other imaging, clinical information, operative surgical intervention, and pulmonary vein histology. The study-specific information included the calculated number of atretic pulmonary veins as well as surgical interventions performed during the study period. The study end points included successful relief of pulmonary vein atresia, recurrence of pulmonary atresia or stenosis, overall pulmonary vein disease progression, and patient survival. A total of 16 patients with one or more pulmonary vein atresias were identified in the cardiac surgery registry database. Of these 16 patients, 5 had primary pulmonary atresia, and 11 had secondary atresia after repair of anomalous pulmonary venous drainage. Surgical recanalization of atretic pulmonary veins was achieved for more than 80% of the patients. At the most recent follow-up assessment, 7 (44%) of the 16 patients had recurrence of atresia. Five of the patients had development of new atresia in other previously healthy pulmonary veins. The median follow-up period was 4 months for primary and 17 months for secondary pulmonary vein atresia. The three main predictors of pulmonary vein disease progression after surgery were the presence of underlying lung disease (P = 0.036), prematurity (P = 0.035), and a history of recurrent pulmonary vein atresia. The overall mortality rate for the patients with primary or secondary pulmonary vein atresia was 56% at the most recent follow-up assessment (100% for the patients with primary vein atresia and 36% for the patients with secondary vein atresia). Surgical recanalization of pulmonary vein atresia is possible, but prognosis remains poor. Recurrence of atresia can take place as early as a few months in the presence of underlying lung disease, prematurity, or history of recurrent pulmonary vein atresia. Further research is needed to identify mechanisms for attaining and sustaining pulmonary vein patency after surgery.

In Vivo Wall Shear Stress Distribution in the Carotid Artery

Background— The purpose of this study was to analyze the in vivo distribution of absolute wall shear stress (WSS abs ) and oscillatory shear index (OSI) in the carotid bifurcation and to evaluate its dependence on bifurcation geometry, the presence of internal carotid artery (ICA) stenosis, and recanalization therapy. Methods and Results— Time-resolved 3D blood flow was acquired with flow-sensitive 4D MRI in 64 normal carotid bifurcations and 17 carotid arteries with moderate ICA stenosis (48±6%) or after surgical recanalization. Among 64 normal arteries, atherogenic wall parameters were consistently concentrated in proximal bulb regions of the common (CCA) and internal (ICA) carotid arteries. The fraction of the carotid bulb exposed to atherosclerosis-prone wall parameters (low WSS abs below and high OSI above group-defined 20% and 10% thresholds) was correlated with the individual bifurcation geometry. Multiple regressions revealed significant ( P <0.01) relationships (β, 0.44 to 0.48) between the areas with atherosclerosis-prone wall parameters and the d ICA /d CCA diameter ratio. The size of regions exposed to high OSI demonstrated highly significant ( P ≤0.01) relationships with all analyzed geometry parameters (d ICA /d CCA β, 0.48; tortuosity β, ≤−0.56; bifurcation angle β, ≥0.47). Moderate ICA stenosis altered the distribution of wall parameters (45%/61% reduction of individually low WSS abs /high OSI in the proximal ICA), which were relocated to segments distal to the arterial stenosis. WSS abs /OSI topology after recanalization was similar compared with the normal wall parameter distribution. Conclusions— Flow-sensitive 4D MRI identified alterations in the segmental in vivo WSS distribution associated with atherosclerotic disease, surgical therapy, and individual bifurcation geometry and could be a valuable technique to assess the individual risk of flow-mediated atherosclerosis and carotid plaque progression.

Disseminated intravascular coagulation with acutely-thrombosed popliteal aneurysm.

Disseminated intravascular coagulation (DIC) is an extremely rare complication of acute thrombosis in popliteal aneurysms and makes it difficult to restore the blood flow with thrombolytic therapy or surgical repair. A 75-year-old man with a history of hypertension presented to the emergency department with complaints of right leg pain and bleeding tendency over a 5-day period. The laboratory findings and multislice computed tomography were suggestive of overt DIC caused by acute thrombosis in the right popliteal aneurysm. Successfully treated with medication, he could discharge without surgical or thrombolytic recanalization of the aneurysm.

Stent-Assisted Recanalisation of Acute Occlusive Arteries in Patients with Acute Limb Ischaemia

To assess the efficacy of stent-assisted recanalisation for acute limb ischaemia in patients considered unfit for thrombolysis or in patients with failed surgical recanalisation. Fifteen patients with acute limb ischaemia, treated with stent implantation, were analysed retrospectively. The reasons for acute limb ischaemia were a cardiogenic embolism (n=3), a traumatic injury (n=3), acute in situ thrombosis with atherosclerosis (n=6), immediate graft thrombosis (n=2), or a delayed thrombotic occlusion after a thrombin injection in the pseudoaneurysm (n=1). This study examined the technical and clinical outcomes of the procedures, including complications during the procedural and follow-up periods. Stent-assisted recanalisation was technically successful and provided immediate recanalisation in all patients (15/15 patients, 100%) and reduced or eliminated the clinical symptoms in 12 patients (12/15 patients, 80%). Two patients died of multi-organ failure related to reperfusion injury, and one patient with a crash injury underwent a below-the-knee amputation as a result of wound necrosis despite recanalisation of the occluded bypass graft. Stent-assisted recanalisation has a high technical success rate with good clinical results as a bailout procedure for the management of acute limb ischaemia in patients, considered unfit for thrombolysis or in patients with failed surgical recanalisation.

Rescue microsurgery in coil herniation causing thromboembolic occlusion of parent artery

Malpositioned coils can provoke abrupt occlusion of the parent vessels and/or neighboring branches causing stroke during coil embolization (CE) of intracranial aneurysms. The authors describe a series of cases in which urgent surgical recanalization of the vessels clogged with herniated or migrated coils rescued the patients. A total of six patients with aneurysms who underwent surgical management for parent artery occlusion linked with inadvertent coil herniation were selected. Their medical-surgical records and operative video recordings were reviewed retrospectively. There were five females and one male whose ages ranged from 44 to 59 years. Occluded vessels associated with CE were three A2 segments of the anterior cerebral artery (ACA), two M2 segments of the middle cerebral artery (MCA) and one superior cerebellar artery (SCA). Surgical management included securing control of both the proximal and distal parent artery, making small openings, safe removal of coils, thorough cleaning of debris and thrombus, and subsequent closure of the opening, which was successful in five of patients and resulted in excellent clinical outcome. However, in the SCA case, surgical retrieval of coils failed due to technical difficulties and yielded untoward results. This report demonstrates that timely surgical intervention could be considered as a safe and effective option to solve serious thromboembolic complications of CE associated with herniated coils.

Primary Stent Placement of an Acute Occlusion in the Iliac Arteries of Patients with Acute Limb Ischemia

Purpose: To assess the efficacy of stent-assisted recanalization for the management of acute limb ischemia (ALI) after a failed surgical revascularization in patients with acute iliac arterial occlusion and considered unfit for a thrombolysis. Materials and Methods: The data on 6 patients with acute limb ischemia due to iliac arterial occlusion, and treated with stent implantation between November 2005 and March 2008, was analyzed retrospectively. The reasons for ALI in the patients analyzed included acute thrombosis related to a traumatic injury (n=3), acute in-situ thrombosis with pre-existing atherosclerotic stenosis (n=2), and cardiogenic embolism (n=1). A preprocedural CT angiography and conventional angiography revealed an occlusion at the iliac artery. This study examined the clinical data, technical and clinical outcome of the procedure, and complications related to the procedure or follow-up period for each patient. Results: Primary stenting was technically successful in all patients, thus resulting in the reduction or elimination of clinical symptoms in the 5 patients observed. One patient expired due to multi-organ failure related to a reperfusion injury. The other five patients showed good clinical results without symptom recurrence and normal duplex USG or CT angiographic findings during the 3-15 month follow-up period. Conclusion: A stent-assisted recanalization is an effective treatment for patients with ALI, which are considered unfit for thrombolysis and surgical recanalization.

Combined endovascular and surgical recanalization after central venous catheter-related obstructions

Central venous occlusion in children is a challenging problem that can occur after a central venous catheter insertion. Long-term catheter-related complications include sepsis and venous thrombosis with consequent loss of central access. We describe 2 cases of children younger than 1 year who were dependent on a central venous catheter for total parenteral nutrition. They developed a chronic extensive obstruction of the right and left brachiocephalic veins with a superior vena cava syndrome. The patients' survival was dependent on the restoration of central venous access until the planned intestinal transplantation could be performed. Retrograde recanalization of the superior vena cava was successfully achieved using a pathway created under general anesthesia from the femoral vein to, respectively, the right thyroid vein and the right subclavian vein.

Primary Infrainguinal Subintimal Angioplasty in Diabetic Patients

The aim of this study was to prospectively evaluate technical and clinical results of infrainguinal subintimal angioplasty in a series of diabetic patients with limb-threatening ischemia. From July 2003 to December 2007, 60 consecutive diabetic patients (M/F = 41/19; mean age, 69.4 +/- 9.4 years) with Fontaine stage IV critical limb ischemia, not suitable for surgical recanalization, underwent primary infrainguinal subintimal angioplasty. The technical success, perioperative morbidity and mortality, and clinical success (defined by ulcer healing) were evaluated. Kaplan-Meier life-table analysis was obtained for cumulative clinical success, limb salvage, and survival rates. The procedure was technically successful in 55 of 60 (91.7%) patients; in 5 cases we were not able to achieve a reentry. Periprocedural mortality was 5% (3 patients); three patients (5%) required major amputation periprocedurally. Mean follow-up was 23 months (range, 0-48 months). On an intention-to-treat basis, the limb salvage rate was 93.3% (56/60 patients); ulcer healing was observed in 45 of 60 (75%) patients and it was significantly (p < 0.05) associated with serum creatinine and HbA1c levels, diabetes duration, and infrapopliteal recanalization. One- and three-year cumulative survival rates were 91.5% and 83.1%, respectively; serum creatinine levels, patient age, and clinical success were significant predictors of survival. In conclusion, infrainguinal primary subintimal angioplasty is a safe and effective treatment in diabetic patients with limb-threatening ischemia not suitable for surgical recanalization. This procedure is aimed to create a "temporary bypass" that facilitates ulcer healing.

Perfusion Computed Tomography–Guided Subacute Endovascular Reperfusion in a Patient with Carotid Occlusion

Most patients with symptomatic internal carotid artery occlusion have a single minor or major hemispheric stroke. A minority of patients have ipsilateral retinal ischemia, recurrent strokes, or transient ischemic attacks. Whereas spontaneous carotid recanalization is rare, acute surgical recanalization has been attempted, with mixed results. Recently, acute endovascular recanalization has been performed and described as feasible and relatively safe. We describe a patient with symptom recurrence related to hemodynamic factors after occlusion of the carotid artery who was successfully treated 14 days after symptom onset.

Management of macular edema in branch retinal vein occlusion with sheathotomy and recombinant tissue plasminogen activator.

The common adventitial sheath that surrounds the retinal venule and arteriole at the crossing site plays a crucial role in branch retinal vein occlusion (BRVO). The purpose of this study was to report the surgical recanalization of the occluded vein using a bimanual technique and recombinant tissue plasminogen activator (tPA) and its effect on final visual acuity. Arteriovenous sheathotomy was performed, using a bimanual technique, followed by fluid-air exchange and injection of 25 mg of recombinant tPA over the area of the occluded vein. Intraoperative sectioning of the common arteriovenous sheath was achieved in all 40 patients. Thrombus release was observed in 11 cases (27.5%) and was correlated with early surgery (P < 0.001) and better final visual recovery (P < 0.06). Optical coherence tomography showed macular thickness that decreased by greater than 40% in 31 patients (77.5%) compared with preoperatively, and correlated to postoperative visual acuity (P < 0.001). The mean visual acuity increased from 20/100 to 20/40, with 70% of patients gaining three or more lines of visual acuity (Pearson 0.378, P = 0.016). Surgical venous decompression and injection of recombinant tPA may effectively manage macular edema secondary to BRVO, thus improving anatomic and visual outcome. Early surgical intervention may obtain maximum final visual recovery.

Recanalizing therapies in acute stroke

Systemic thrombolysis with rt-PA within 3 hours after symptom onset has developed into a standard therapy for acute stroke patients. Recombinant t-PA is now licensed in Europe for this indication. Within 3 to 6 hours, no general therapeutic standard has been established yet. Currently, the available data are in favor of intra-arterial thrombolysis for patients with proximal occlusions of the middle cerebral artery. Systemic thrombolysis is not generally recommended in this time window, but is used in some centers for selected patients. In addition to thrombolysis and new strategies to improve thrombolysis (including patient selection with MRI), several interventional and surgical recanalization techniques are discussed.

Rekanalisierende Behandlung des akuten Schlaganfalls

ZusammenfassungDie systemische Thrombolyse der akuten zerebralen Ischämie mit rt-PA im 3-Stunden-Zeitfenster entwickelte sich in den vergangenen Jahren zur Standardtherapie. Seit Ende 2002 besteht eine europaweite Zulassung für diese Indikation. Für das 3- bis 6-Stunden-Zeitfenster gibt es bislang noch keine allgemein akzeptierte Behandlungsstrategie. Die Datenlage ist am günstigsten für die intraarterielle Thrombolyse, vorausgesetzt es liegt ein proximaler Verschluss der Arteria cerebri media vor. Eine systemische Thrombolyse jenseits der ersten 3 Stunden wird nicht generell empfohlen, aber in einzelnen Zentren bei ausgewählten Patienten durchgeführt. Neben Thrombolyseverfahren im engeren Sinne und neuen Ansätzen zur Optimierung thrombolytischer Therapie (z. B. Patientenauswahl mittels MRT) werden einzelne neuroradiologisch-interventionelle und chirurgische Rekanalisierungsmethoden diskutiert.

Correlation between radiotherapy and suture fistulas following colo-anal anastomosis for carcinoma of the rectum evaluation of 152 consecutive patients.

The aim of this study was to evaluate the prevalence of suture fistulas and their possible correlation with adjuvant therapy in patients who underwent colo-anal anastomosis and J pouch reconstruction with a protective colostomy. The reliability of the radiological screening and monitoring program was also verified. One hundred and fifty-two consecutive patients were evaluated radiologically with water-soluble radio-opaque contrast enema before surgery for closure of the protective colostomy. Fifty-seven patients were treated with surgery alone (group A) and 95 patients received adjuvant treatment (group B). A total of 54 fistulas were seen: 17 in group A (28.9% of patients in group A) and 37 in group B (38.9% of patients in group B). Six fistulas involved the rectovaginal septum. All fistulas were managed medically. The time to resolution was 30 days in 76.4% of patients in group A and about 50 days in 82% of patients in group B. Rectovaginal fistulas always took much longer to heal in both groups and failed to heal in two of the four cases in group B. Two factors appear to contribute to the high prevalence of fistulas in this series: extension of radiological screening to all operated patients and adjuvant radiotherapy. However, the postoperative course was not compromised by radiotherapy in that these fistulas resolved with medical treatment alone, although healing took longer. The incidence of rectovaginal fistulas was substantially the same in the two groups, but two of the four occurring in group B did not heal. Postoperative monitoring with water-soluble contrast enema appears to be the diagnostic procedure of choice because it is well tolerated, non-invasive and a reliable aid in planning surgical bowel recanalization since no false negative cases were detected clinically after closure of the colostomy.

Emergency surgical recanalisation of A1 segment occluded by a Guglielmi detachable coil

We describe a case of A1 segment occlusion caused by a tangled Guglielmi detachable coil (GDC) during an endovascular treatment for a ruptured anterior communicating aneurysm. Immediate surgical recanalisation of the occluded artery and clipping of the aneurysm rescued the patient. This case demonstrates that an emergency surgical team, as well as an operating room, should be available during any complicated intra-aneurysmal procedure, so that timely surgical intervention could be carried out without delay.

Diagnostic approach of pulmonary embolism by spiral angioscanner

Spiral volumetric computerized tomography (CT) allows the exploration of the whole chest during a single contrast injection and breath-hold. For the diagnosis of central pulmonary embolisms, the sensibility is between 78 and 98% and the specificity between 86 and 94% depending on the direct visualization of the endoluminal defect. Detection of intercurrent parenchymal pathologies or of non-obstructive arterial thrombi explain some false positive or inconclusive results of the ventilation-perfusion scintigraphy. Sub-segmental thrombi are less easily detected and sensibility for both central and sub-segmental embolisms is only 63%, explaining some rare false negatives of the CT on isolated sub-segmental embolisms. Chronic thrombi are outlying and contiguous with the arterial wall. They are associated with arterial stenosis, cut-off and loops and an oligemic mosaic pattern of the parenchyma. CT allows pre-operative staging before surgical recanalization and the intra-venous injection does not interfere with the arterial pressure. CT is a non-invasive, reliable and easily available technique which clearly plays an important role in the diagnosis of pulmonary embolism.