Concordant dynamic changes of global network properties in the frontoparietal and limbic compartments: An EEG study.

INTRODUCTION: Despite its complexity, deciphering nodal interaction is imperative to understanding a neural network. Network interaction is an even more complicated topic that must be addressed. This study aimed to examine the relationship between the brain waves of two canonical brain structures, i.e., the frontoparietal and limbic compartments, during a resting state. METHODS: Electroencephalography (EEG) of 51 subjects in eye-closed condition was analyzed, and the eLORETA method was applied to convert the signals from the scalp to the brain. By way of community detection, representative neural nodes and the associated mean activities were retrieved. Total and lagged coherences were computed to indicate functional connectivity between those neural nodes. Two global network properties were elucidated based on the connectivity measures, i.e., global efficiency and mean functional connectivity strength. The temporal correlation of the global network indices between the two studied networks was explored. RESULTS: It was found that there was a significant trend of positive correlation across the four metrics (lagged vs. total coherence x global efficiency vs. average connectivity). In other words, when the neural interaction in the FP network was stronger, so did that in the limbic network, and vice versa. Notably, the above interaction was not spectrally specific and only existed at a finer temporal scale (under hundreds of milliseconds level). CONCLUSION: The concordant change in network properties indicates an intricate balance between FP and LM compartments. Possible mechanisms and implications for the findings are discussed.

Breast Density Legislation: Discussion of Patient Utilization and Subsequent Direct Financial Ramifications for Insurance Providers.

Now that New Jersey has become the 14th state in the United States to enact legislation regarding dense breast screening, its patients are eligible to receive screening breast sonography coverage from their insurance carriers. This law is intended to improve breast cancer detection in patients with dense breasts and create awareness of unique issues that come with dense breast tissue, while reinforcing already present efforts to reduce the incidence of and morbidity related to the diagnosis of breast cancer. The aim of this study was to examine data from months preceding the effective date of this legislation in a community hospital setting and compare these data with data from months immediately after, and 6 months after, its enactment to present patient participation data and estimate the legislation's direct financial ramifications. Detractors of this type of legislation worry about overburdening the health care system with an influx of patients. Although there is a lack of present studies confirming this suspicion in other states with dense breast legislation, this study confirms a large increase in patient utilization after enactment, showing a minimum relative increase of 176.90% and a maximum relative increase of 335.56% in patient utilization of screening breast sonography. The investigators further include an estimation of an increased direct cost for insurers of $4,910,899.18 to $9,848,897.96 for a given month.

Embolization of isolated lumbar artery injuries in trauma patients.

PURPOSE: The purpose of the study was to evaluate the angiographic findings and results of embolotherapy in the management of lumbar artery trauma. METHODS: All patients with lumbar artery injury who underwent angiography and percutaneous embolization in a state trauma center within a 10-year period were retrospectively reviewed. Radiological information and procedural reports were reviewed to assess immediate angiographic findings and embolization results. Long-term clinical outcome was obtained by communication with the trauma physicians as well as with chart review. RESULTS: In a 10-year period, 255 trauma patients underwent abdominal aortography. Eleven of these patients (three women and eight men) suffered a lumbar artery injury. Angiography demonstrated active extravasation (in nine) and/or pseudoaneurysm (in four). Successful selective embolization of abnormal vessel(s) was performed in all patients. Coils were used in six patients, particles in one and gelfoam in five patients. Complications included one retroperitoneal abscess, which was treated successfully. One patient returned for embolization of an adjacent lumbar artery due to late pseudoaneurysm formation. CONCLUSIONS: In hemodynamically stable patients, selective embolization is a safe and effective method for immediate control of active extravasation, as well as to prevent future hemorrhage from an injured lumbar artery.

Angiographic findings and embolotherapy in renal arterial trauma.

PURPOSE: To evaluate the angiographic findings and embolotherapy in the management of traumatic renal arterial injury. METHODS: This is a retrospective review of 22 patients with renal trauma who underwent arteriography and percutaneous embolization from December 1995 to January 2002. Medical records, imaging studies and procedural reports were reviewed to assess the type of injury, arteriographic findings and immediate embolization results. Long-term clinical outcome was obtained by communication with the trauma physicians and by clinical chart review. RESULTS: Arteriography was performed in 125 patients admitted to a State Trauma Center with suspected internal bleeding. Renal arterial injury was documented in 22 and was the result of a motor-vehicle accident (10), auto-pedestrian accident (1), gunshot (4) or stab wounds (6) and a fall (1). Percutaneous renal arterial embolization was undertaken in 22 of 125 (18%) patients to treat extravasation (11), arterial pedicle rupture (5), abnormal arteriovenous (3) or arteriocalyceal (2) communication and pseudoaneurysm (3). One of the pseudoaneurysms and one of the arteriovenous fistulae were found in addition to extravasation. All 22 patients (16 men, 6 women) were hemodynamically stable, or controlled during arteriography and embolotherapy. Selective and/or superselective embolization of the abnormal vessels was performed using coils in 9 patients, microcoils in 9 patients and Gelfoam pledgets in 3 patients. In one patient Gelfoam pledgets mixed with polyvinyl alcohol (PVA) particles were used for embolization. Immediate angiographic evidence of hemostasis was demonstrated in all cases. Two initial technical failures were treated with repeat arteriography and embolization. There was no procedure-related death. There was no non-target embolization. One episode of renal abscess after embolization was treated by nephrectomy and 3 patients underwent elective post-embolization nephrectomy to prevent infection. Follow-up ranged from 1 month to 7 years (mean 31 months). No procedure-related or delayed onset of renal insufficiency occurred. CONCLUSION: In hemodynamically stable and controlled patients selective and superselective embolization is a safe and effective method for the management of renal vascular injury.

Histopathologic evaluation of tissue extracted on the radiofrequency probe after ablation of liver tumors: preliminary findings.

OBJECTIVE: Our aim was to evaluate the histologic characteristics of tissue extracted on the probe immediately after radiofrequency ablation of malignant tumors in the liver. MATERIALS AND METHODS: From April to December 2001, 20 radiofrequency ablations were performed in 19 patients with primary (n = 17) and metastatic (n = 2) liver masses. Track ablation according to device protocol was performed after each ablation. Tissue was adherent to the probe after all radiofrequency probe passes. All pieces of tissue found on the probe were collected and preserved in formalin. RESULTS: Tissue was examined by the study pathologist. In eight (40%) of 20 specimens, coagulation necrosis was present. In five (25%) of 20 specimens, possibly nonviable tissue was extracted, although some cell characteristics were identified. In seven (35%) of 20 specimens with hepatocellular carcinoma, possibly viable tissue was found. Five specimens were identified as hepatocellular carcinoma, and two, as cirrhotic nodules. CONCLUSION: Histopathologic evaluation of the tissue extracted on the radiofrequency probe after ablation is feasible. This study showed that coagulation necrosis was clearly present in at least 40% of the patients, which proves that nonviable tissue can be seen immediately after ablation. Whether this pathologic finding has prognostic value is not known.

CT evaluation of an anterior urethral tear.

A retrograde urethrogram is usually performed to evaluate the urethra in patients with suspected urethral injuries. A computed tomography (CT) scan is performed after the retrograde urethrogram to evaluate for further intrabdominal injuries. We present a case in which a CT scan performed after a retrograde urethrogram in a trauma patient identified a urethral tear.

Prospective validation of computed tomographic screening of the thoracolumbar spine in trauma.

OBJECTIVE: Concern for thoracolumbar spine (TLS) injuries after major trauma mandates immobilization pending radiographic evaluation. Current protocols use standard posteroanterior and lateral radiographs of the thoracolumbar spine (XR/TLS), but many patients also undergo abdominal or thoracic computed tomographic (CT) scanning. We sought to evaluate whether helical truncal CT scanning performed to evaluate visceral trauma images the spine as well as dedicated XR/TLS. METHODS: We prospectively studied 222 consecutive patients sustaining high-risk trauma requiring TLS screening because of clinical findings or altered mentation. The chest, abdomen, and pelvis were imaged with one intravenous contrast infusion. All patients had CT scan of the chest, abdomen, and pelvis (CT/CAP) and XR/TLS. Initial radiologic diagnoses were compared with the discharge diagnosis of acute fractures confirmed by thin-cut CT scan and/or clinical examination of the patient when alert. RESULTS: Of 222 patients studied, 215 were fully evaluated. Thirty-six (17%) had acute TLS fractures. The accuracy of CT/CAP for TLS fractures was 99% (95% confidence interval [CI], 96-100%). The accuracy of XR/TLS was 87% (95% CI, 82-92%). Sensitivity, specificity, and positive and negative predictive values were better for CT/CAP than for XR/TLS. CT/CAP found acute fractures XR/TLS missed, and correctly classified old fractures XR/TLS read as "possibly" acute. The total XR/TLS misclassification rate was 12.6% (95% CI, 8.4-19%); for CT/CAP it was 1.4% (95% CI, 0.3-3.3%). No fractures were missed by CT/CAP. No unstable fracture was missed by either technique. CONCLUSION: CT/CAP diagnoses TLS fractures more accurately than XR/TLS. Neither misses unstable fractures, but CT scanning finds small fractures that benefit by treatment and identifies chronic disease better. CT screening is far faster and shortens time to removal of spine precautions. CT scan-based diagnosis does not result in greater radiation exposure and improves resource use. Screening the TLS on truncal helical CT scanning performed for the evaluation of visceral injuries is more accurate than TLS imaging by standard radiography. CT/CAP should replace plain radiographs in high-risk trauma patients who require screening.

Percutaneous treatment of complications occurring during hemodialysis graft recanalization.

INTRODUCTION/OBJECTIVE: To describe and evaluate percutaneous treatment methods of complications occurring during recanalization of thrombosed hemodialysis access grafts. METHODS AND MATERIALS: A retrospective review of 579 thrombosed hemodialysis access grafts revealed 48 complications occurring during urokinase thrombolysis (512) or mechanical thrombectomy (67). These include 12 venous or venous anastomotic ruptures not controlled by balloon tamponade, eight arterial emboli, 12 graft extravasations, seven small hematomas, four intragraft pseudointimal 'dissections', two incidents of pulmonary edema, one episode of intestinal angina, one procedural death, and one distant hematoma. RESULTS: Twelve cases of post angioplasty ruptures were treated with uncovered stents of which 10 resulted in graft salvage allowing successful hemodialysis. All arterial emboli were retrieved by Fogarty or embolectomy balloons. The 10/12 graft extravasations were successfully treated by digital compression while the procedure was completed and the graft flow was restored. Dissections were treated with prolonged Percutaneous Trasluminal Angioplasty (PTA) balloon inflation. Overall technical success was 39/48 (81%). Kaplan-Meier Primary and secondary patency rates were 72 and 78% at 30, 62 and 73% at 90 and 36 and 67% at 180 days, respectively. Secondary patency rates remained over 50% at 1 year. There were no additional complications caused by these maneuvers. DISCUSSIONS AND CONCLUSION: The majority of complications occurring during percutaneous thrombolysis/thrombectomy of thrombosed access grafts, can be treated at the same sitting allowing completion of the recanalization procedure and usage of the same access for hemodialysis.

Gossypiboma treated by colonoscopy.

Gossypibomas are an unusual postoperative complication and are reluctantly reported in the literature. In the past, the patient would require a laparotomy. More recently, they have been treated laparoscopically and percutaneously by interventional radiology. This is the first case report of a gossypiboma treated with colonoscopy. This may represent an addition treatment option for this complication.

Alteplase for hemodialysis access graft thrombolysis.

PURPOSE: To evaluate the efficacy and safety of alteplase, a recombinant tissue plasminogen activator, in hemodialysis access graft thrombolysis. MATERIALS AND METHODS: From November 1999 to May 2001, 68 episodes of occlusion in 50 grafts (in 49 patients) were included in the study. Occlusion was treated with pulse-spray (n = 41) or lyse-and-wait (n = 27) thrombolysis with use of alteplase. Balloon angioplasty of all identified stenoses was performed. The arterial plug was mobilized with the Fogarty maneuver. RESULTS: Procedural success was achieved in 64 of 68 episodes (94%) with a dose of 2-10 mg (mean = 4.13 mg) of alteplase, allowing successful hemodialysis within 24 hours. Failures (6%) were the result of PTA perforation (one of 68), nonnegotiable outflow occlusion (one of 68), delayed bleeding (one of 68), and balloon bursting and shearing becoming occlusive within the graft (one of 68). Primary and secondary patency rates were 72% and 87% at 30 days, 57% and 80% at 90 days, and 44% and 72% at 180 days, respectively. Arterial emboli (two of 68) were treated by Fogarty balloon retrieval and alteplase infusion locally over the course of 20 minutes. One of two PTA perforations was controlled by balloon tamponade. CONCLUSION: Alteplase can be used successfully for hemodialysis graft thrombolysis.

Transvenous transjugular renal core biopsy with a redesigned biopsy set including a blunt-tipped needle.

A novel 19-gauge, blunt-tipped, side cutting single throw, 70-cm long transjugular needle, specifically designed for transvenous kidney biopsy, was used in seven patients with high risk for bleeding. A mean of 4 device-passes (3-6) per patient resulted in a satisfactory specimen for pathological diagnosis. Immediate post-biopsy nonenhanced CT was performed to evaluate for bleeding at the biopsy site. All patients were observed for 2 hr after the procedure. No clinically significant immediate or late complication was noted.

Is coagulopathic liver disease a factor in spontaneous cerebral hemorrhage?

PURPOSE: Hepatic dysfunction is a common cause of thrombocytopenia and coagulopathy and has been reported as a causal factor in spontaneous intracranial hemorrhage. We attempt to define the prevalence of intracranial hemorrhage in patients with severe liver disease and coagulopathy. METHOD: We retrospectively reviewed the medical records, CT, and MRI acquired between January 1996 and August 1999 of patients with liver disease and a coagulopathy admitted for nontraumatic acute mental status changes. RESULTS: In 138 CT and MR scans performed on the 100 patients described above, no cases of spontaneous intracranial bleeding were detected. CONCLUSION: Contrary to past reports, we find no instance of spontaneous intracranial hemorrhage in patients with coagulopathic liver disease presenting with acute mental status changes. Therefore, unless associated with trauma, spontaneous intracranial hemorrhage in coagulopathic liver disease is very uncommon.

Virtual endoscopy for evaluation of tracheal laceration.

Rigid or fiberoptic endoscopy is performed to evaluate the trachea in a patient with suspected tracheal injury. We present a case in which CT virtual endoscopy identified a tracheal laceration not seen on axial or sagittal reformations. This case highlights the usefulness of this modality in the diagnosis and preoperative planning of tracheal injury.