Efficacy of intraoperative wireless ultrasonography for uterine incision among patients with adherence findings in placenta previa.

AIM: We evaluated the effectiveness of intraoperative wireless ultrasonography in determining the location of uterine incision during cesarean delivery in patients with placenta previa who have sonographic adherence findings in order to assess intraoperative blood loss and maternal morbidity. METHODS: A prospective study using wireless sonography, including 15 patients with previa, was conducted among women with singleton pregnancies who delivered by cesarean section between August 1, 2017, and August 30, 2019. Retrospective study for the control group included 32 patients with placenta previa who underwent cesarean section between January 1, 2016, and July 31, 2017, without wireless sonography. Patients with previa who had adherence findings in prenatal sonography were included in both groups. Logistic regression was used to identify the association between massive intraoperative bleeding loss and use of wireless ultrasound sonography. RESULTS: Intraoperative blood loss was significantly reduced in the study group compared to that in the control group (P = 0.009). The hospital stay was significantly shorter in the study group compared to the control group (5 days vs 6 days, P < 0.001). The use of intraoperative wireless sonography (P = 0.01) had a significant association with massive intraoperative hemorrhage in multivariable analysis. CONCLUSION: Our study is the first study to apply a wireless ultrasound sonography device in women with placenta previa during cesarean section to examine maternal morbidity. This latest wireless ultrasound sonography device is advantageous for uterine incision guidance in women with placenta previa and improves maternal morbidity by reducing intraoperative hemorrhage.

Remedial operations for failed endovascular therapy of 32 renal artery stenoses in 24 children.

BACKGROUND: Percutaneous transluminal angioplasty (PTA) for the treatment of pediatric renovascular hypertension (RVH) in contemporary practice is accompanied with ill-defined complications. This study examines the mode of pediatric renal PTA failures and the results of their surgical management. METHODS: Twenty-four children underwent remedial operations at the University of Michigan from 1996 to 2014 for failures of renal PTA. Their clinical courses were retrospectively reviewed and results analyzed. RESULTS: Renal PTA of 32 arteries, including 13 with stenting, was performed for severe RVH in 12 boys and 12 girls, having a mean age of 9.3 years. Developmental ostial stenoses affected 22 children. PTA failures included: 27 restenoses and five thromboses. Remedial operations included: 13 renal artery-aortic reimplantations, one segmental renal artery-main renal artery reimplantation, ten aortorenal bypasses, one arterioplasty, one iliorenal bypass, and six nephrectomies for unreconstructable arteries; the latter all in children younger than 10 years. Follow-up averaged 2.1 years. Postoperatively, hypertension was cured, improved, or unchanged in 25, 54, and 21 %, respectively. There was no perioperative renal failure or mortality. CONCLUSIONS: Renal PTA for the treatment of pediatric RVH due to ostial disease may be complicated by failures requiring complex remedial operations or nephrectomy, the latter usually affecting younger children.

Image-guided intervention in management of complications of portal hypertension: more than TIPS for success.

Management of clinically important sequelae of portal hypertension, such as variceal bleeding and ascites, may involve a combination of medical, endoscopic, surgical, and interventional approaches and procedures. Although clinically significant esophageal and rectal varices are typically visible endoscopically, ectopic varices may require multiplanar portal venous phase computed tomography or magnetic resonance imaging for diagnosis. A detailed understanding of individual vascular anatomy, flow dynamics, and patient-related factors such as cardiac and hepatic status is necessary for appropriate treatment selection in patients with complicated portal hypertension. The hepatic venous pressure gradient is the key indirect measurement of portal venous pressure. Transjugular intrahepatic portosystemic shunt (TIPS) placement is regarded as the archetypal intervention for treating complicated portal hypertension by reducing portal pressure. Various modifications, such as direct portocaval shunt, may be used in patients with challenging vascular anatomy. A subset of patients with obstructed hepatic venous outflow or portal venous inflow should be considered for recanalization. Splenic artery embolization may be considered for reduction of portal pressure in selected patients, particularly when hypersplenism or splenic vein occlusion is a prominent feature. Gastric and ectopic varices may bleed even when the portal pressure is low, and balloon-occluded retrograde transvenous obliteration (BRTO) in such patients may lead to equal or improved outcome compared with TIPS placement. BRTO is not limited by poor hepatic reserve or encephalopathy; however, it does not reduce portal pressure and may aggravate esophageal varices. Interventional radiology plays an important role in maintaining the patency of surgically created portosystemic shunts, and it remains at the forefront of new approaches in shunt design and placement. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.335125166/-/DC1.

Isolation, screening and identification of Swine gut microbiota with ochratoxin a biodegradation ability.

The potential for ochratoxin A (OTA) degradation by swine intestinal microbiota was assessed in the current study. Intestinal content that was collected aseptically from swine was spiked with 100 ppb OTA and incubated for 6 and 12 h at 39°C. An OTA assay was conducted using the incubated samples, and it was found that 20% of the OTA toxin was detoxified, indicating the presence of microbes capable of OTA degradation. Twenty-eight bacterial species were isolated anaerobically in M 98-5 media and 45 bacterial species were isolated using nutrient broth aerobically. Screening results showed that one anaerobic bacterial isolate, named MM11, detoxified more than 75% of OTA in liquid media. Furthermore, 1.0 ppm OTA was degraded completely after 24 h incubation on a solid 'corn' substrate. The bacterium was identified by 16S rDNA sequencing as having 97% sequence similarity with Eubacterium biforme. The isolation of an OTA-degrading bacterium from the swine natural flora is of great importance for OTA biodegradation and may be a valuable potential source for OTA-degradation enzymes in industrial applications.

Surgical removal of a Günther Tulip filter with symptomatic caval penetration after unsuccessful percutaneous retrieval.

We report a case involving the surgical removal of a Günther Tulip filter with symptomatic caval penetration after an unsuccessful attempt at percutaneous retrieval in a 32-year-old man with recurrent deep vein thrombosis. He presented with acute right flank pain a day after the attempted retrieval of the filter. An abdominal radiograph before surgical removal of the filter showed tilting and splaying of the filter, which was suggestive of caval penetration. Contrast-enhanced computerized tomography confirmed caval penetration of the filter legs into the retroperitoneal space, right renal vein, and duodenum associated with a small retroperitoneal fluid collection. Surgical removal of the filter by a transperitoneal approach resulted in resolution of the flank pain.

Retrievability of optional inferior vena cava filters with caudal migration and caval penetration: report of three cases.

The present report describes the safe retrieval of caudally migrated optional inferior vena cava (IVC) filters with significant IVC penetration. Three patients had optional IVC filters placed for deep vein thrombosis/pulmonary emboli and contraindications for anticoagulation. Subsequent imaging showed caudal migration and penetration of the filter legs through the IVC wall. All filters were removed without major complications. One patient experienced abdominal pain after filter removal, which required no treatment. Caudal migration of optional filters with IVC wall penetration by the filter legs may be more common with new filter designs in which the secondary and primary struts are separated.

The Günther-Tulip retrievable filter: a method for assessing tilting of the filter.

PURPOSE: Tilting of the Günther-Tulip filter may be responsible for failure or difficulty to retrieve. Assessment of the filter tilt can be difficult when only AP imaging is available. This study is performed in vitro to develop a simple method to assess the Günther-Tulip filter for tilting. MATERIALS AND METHODS: A model consisting of a plastic tube was used to simulate vena cava. A Günther-Tulip filter was placed centred or tilted within the tube at various positions and radiograms were taken in AP, lateral, and craniocaudally angled projections. The images were analysed to determine the actual degree of tilt, the distance between the limb hooks on AP radiograms and the craniocaudal angulation degree needed to align the limb hooks linearly. RESULTS: When the filter was centred or tilted laterally, all limb hooks of the filter were aligned linearly on AP radiograms. When the filter was tilted in AP or oblique direction, linear alignment of the limb hooks was lost and the ventral and dorsal limb hooks showed separation on AP projection. The amount of separation and the craniocaudal angles to align the filter hooks corresponded to actual tilt angles. CONCLUSION: Loss of linear alignment of limb hooks in AP radiograms may suggest the presence of tilt in the AP plane. Significant separation of limb hooks should be alarming for significant filter tilt, and further evaluation of the filter position by CT scan or lateral cavogram should be obtained prior to planning of the retrieval.

Carbon dioxide in angiography to reduce the risk of contrast-induced nephropathy.

In the 1970s, Hawkins pioneered the intra-arterial use of carbon dioxide gas for high-risk patients who were allergic to iodinated contrast material and for those with renal failure. With the advent of digital subtraction angiography in 1980, reliable imaging of "low-density" CO(2) contrast agent became available. Subsequently, with the addition of high-resolution of digital subtraction angiography, stacking software (adding multiple images), tilting tables and a reliable, user-friendly delivery system, CO(2) imaging has become nearly comparable to and, in some cases, superior to that of iodinated contrast media. It is the only safe contrast agent for patients in renal failure, which is extremely important in view of the increasing incidence of diabetes and complexities of interventional procedures. The low viscosity of CO(2) not only improves the sensitivities of several diagnostic procedures but may afford advantages for several interventional procedures.

False-positive "Cavernous Transformation" secondary to lymphatic filling in parenchymal hepatic CO(2) injection for portal vein visualization in TIPS procedures.

PURPOSE: To determine the frequency and potential importance of findings initially interpreted as portal vein occlusion with "cavernous transformation" at transjugular intrahepatic portosystemic shunt (TIPS) placement with hepatic parenchymal CO(2) injection. MATERIALS AND METHODS: One hundred forty-seven patients underwent hepatic parenchymal CO(2) injections in the setting of fine-needle CO(2) TIPS procedures. Hepatic parenchymal CO(2) injections were retrospectively reviewed for findings suggestive of cavernous transformation in which direct portal venography confirmed portal vein patency. Direct portography was performed by injecting CO(2) via the fine needle/guide wire complex or a 5-F catheter in a branch of the intrahepatic portal vein. RESULTS: Hepatic lymphatic vessels mimicked cavernous transformation of the portal vein in 29 of the 147 patients (19.7%). One patient with portal vein occlusion showed profuse lymphatic filling without filling the extrahepatic portal vein. Hepatic parenchymal CO(2) injections safely permitted targeting of the portal vein in all patients. CONCLUSIONS: During fine-needle CO(2) TIPS procedures, what was believed to represent reversed flow of hilar collateral vessels represented hepatic lymphatic vessels. Despite the lack of visualization of the portal vein in nearly one-fifth of patients, targeting of the portal vein was facilitated by the fact the hepatic lymphatic vessels showed a periportal distribution. The high incidence of hepatic lymphatic filling suggestive of cavernous transformation necessitates direct portography or wedged hepatic venography to verify portal vein patency before the procedure is aborted.

Increased cell-free DNA concentrations in patients with obstructive sleep apnea.

AIM: Blood concentrations of cell-free DNA, which is considered to be released during apoptosis, are elevated under some pathological conditions such as cardiovascular disease and cancer. The association between obstructive sleep apnea (OSA) and cell-free DNA concentrations has not been reported so far. The purpose of the present study was to examine the association between OSA and plasma DNA concentrations. METHODS: A case-control study was conducted using a total of 164 men aged 39-67 years, who were free of coronary heart disease and cancer. Laboratory-based overnight polysomnography was performed for all participants. RESULTS: On the basis of polysomnography, patients with an apnea-hypopnea index (AHI) = 5-30 events/h were defined as having mild-moderate OSA (n = 33) and those with >30 events/h were defined as having severe OSA (n = 49). All 82 controls had AHI < 5 events/h. Plasma DNA concentrations from all participants were analyzed for the beta-globin gene using fluorescence-based real-time polymerase chain reaction. Patients with severe OSA had significantly higher plasma DNA concentrations than persons with mild-moderate OSA and those without OSA (P < 0.05). AHI was significantly associated with body mass index (P < 0.001), hypertension (P < 0.001), and plasma DNA concentration (P < 0.05). CONCLUSION: After taking into account hypertension and other potential risk factors, persons with high plasma DNA concentrations (>8 microg/L) had approximately fourfold higher odds of OSA than those with low DNA levels. Further data are warranted to confirm the association for men and to evaluate the association for women.

The role of radiologic studies in the evaluation and management of primary hyperaldosteronism.

BACKGROUND: Surgical treatment of primary hyperaldosteronism (PHA) requires demonstration of unilateral adrenal hypersecretion. Optimal methods for interpretation of imaging and invasive testing are still in development. METHODS: A retrospective review from 1996-2007 of 106 patients with PHA was undertaken. Patient demographics, biochemical studies, radiologic imaging, operative reports, and pathology were reviewed and comparisons made. Optimal ratios for adrenal vein sampling were tested with regard to sensitivity and specificity. Preoperative and postoperative medication requirements and blood pressures were compared among different treatment groups. RESULTS: Seventy-eight patients (62 surgically treated) met criteria for inclusion. Median arterial blood pressure at diagnosis was 150/86 mm Hg while taking 3 antihypertensive medications. 69.2% required potassium supplementation. Median aldosterone:renin ratio was 107.0. Forty-two AVS procedures changed the management of 15 patients (35.7%) when compared to CT results. AVS accuracy was 96.6 vs 88.9% for NP-59 scintigraphy. Operative patients remained on fewer antihypertensive medications (1 vs 3), and mean systolic pressure was lower (130 vs 146 mm Hg) compared with medically managed patients. CONCLUSION: When used together, pre-ACTH aldosterone ratios, normalized A/C:A/C ratios, ratios to define contralateral suppression, and post-ACTH stimulated values allowed for capture of episodically secreting tumors and subtle unilateral or bilateral hyperaldosteronism.

Transjugular intrahepatic portosystemic shunt prior to cardiac surgery with cardiopulmonary bypass in patients with cirrhosis and portal hypertension.

Because of the increased complications associated with cardiac surgery in patients with cirrhosis and portal hypertension, various preoperative preparations have been utilised. In order to reduce the bleeding risk by decompressing portosystemic collaterals and to correct the fluid shift, we performed transjugular intrahepatic portosystemic shunt (TIPS) in two patients with cirrhosis and portal hypertension prior to major cardiac surgery with cardiopulmonary bypass. Both patients had satisfactory surgical outcome with no bleeding complications. One patient developed hepatic encephalopathy which was managed medically. We believe that preoperative TIPS benefits the patient with cirrhosis and portal hypertension undergoing cardiac surgery by decreasing the major surgical complications through improvement of fluid imbalance and reduction of the bleeding risk. Because of the risks of TIPS, such as encephalopathy and liver failure, preoperative TIPS placement must be reserved for patients with fluid shift or high risk criteria of bleeding.

Portal hypertension and obstructive jaundice after hepatic interventions: report of two unusual complications.

We report two unusual complications after a transjugular intrahepatic portosystemic shunt and a biliary stent placement, respectively. One patient with cirrhosis and portal hypertension developed obstructive jaundice secondary to compression of the right hepatic duct by a stent graft placed in the transjugular intrahepatic portosystemic shunt. In another patient, biliary stents caused obstruction of the portal vein, resulting in symptomatic portal hypertension. An awareness of these possible complications is important for early diagnosis and appropriate treatment of such complications.

Pediatric renovascular hypertension: 132 primary and 30 secondary operations in 97 children.

PURPOSE: This study was undertaken to characterize the contemporary surgical treatment of pediatric renovascular hypertension. METHODS: A retrospective analysis was conducted of the clinical data of 97 consecutive pediatric patients (39 girls, 58 boys), aged from 3 months to 17 years, who underwent operation at the University of Michigan from 1963 to 2006. All but one patient had refractory hypertension not responsive to contemporary medical therapy. Developmental renal artery stenoses accounted for 80% of the renal artery disease, with inflammatory and other ill-defined stenoses encountered less frequently. Splanchnic arterial occlusive lesions affected 24% and abdominal aortic coarctations, 33%. RESULTS: Primary renal artery operations were undertaken 132 times. Procedures included resection beyond the stenosis and implantation into the aorta in 49, renal artery in 7, or superior mesenteric artery in 3; aortorenal and iliorenal bypasses with vein or iliac artery grafts in 40; focal arterioplasty in 10; resection with reanastomosis in 4; operative dilation in 4; splenorenal bypass in 2; and primary nephrectomy in 13 when arterial reconstructions proved impossible. Bilateral renal operations were done in 34 children, and 17 underwent celiac or superior mesenteric arterial reconstructions, including 15 at the time of the renal operation. Thirty patients underwent abdominal aortic reconstructions with patch aortoplasty (n = 19) or thoracoabdominal bypass (n = 11). Twenty-five of the aortic procedures were performed coincidently with the renal operations. Thirty secondary renal artery procedures were done in 19 patients, including nine nephrectomies. Hypertension was cured in 68 children (70%), improved in 26 (27%), and was unchanged in three (3%). Follow-up averaged 4.2 years. No patients required dialysis, and there were no operative deaths. CONCLUSION: Contemporary surgical treatment of pediatric renovascular hypertension emphasizes direct aortic implantation of the normal renal artery beyond its stenosis and single-staged concomitant splanchnic and aortic reconstructions when necessary. Benefits accompany carefully executed operative procedures in 97% of these children.