Percutaneous Biliary Interventions: Inside and Outside the Box: Role of Interventional Radiology in Children with Biliary and Gallbladder Diseases

Biliary and gallbladder diseases in infants and children often present unique diagnostic and therapeutic challenges that require a fundamental understanding of notable biliary diseases and anatomical variations. Surgical and endoscopic approaches that are often the gold standard in adult biliary treatment may be technically challenging and are associated with a high morbidity that may warrant a multidisciplinary treatment approach. This article will provide a comprehensive overview of the biliary conditions where interventional radiology can play a vital role in the diagnosis, management, and treatment. Differences in approach or technique between children and adults will be highlighted.     

Tacrolimus-associated hypomagnesemia in renal transplant recipients

BACKGROUND: Since hypomagnesemia occurs frequently in tacrolimus treated patients, we studied the correlation between renal magnesium wasting and tacrolimus blood levels in renal transplant patients. METHODS: Serum magnesium, fractional excretion of magnesium (FEMg), and 24-hour urinary excretion of magnesium were measured in 41 transplant patients and 10 healthy volunteers for correlation with tacrolimus level. RESULTS: Of tacrolimus-treated patients, 43% displayed hypomagnesemia. FEMg (7.42+/-3.59% versus 1.88+/-0.43%) and 24-hour urinary excretion (112.36+/-51.43 mg/dL versus 6.7+/-2.79 mg/dL) were significantly higher among tacrolimus-treated patients than controls. Magnesium replacement did not influence FEMg or 24-hour urinary magnesium excretion. Tacrolimus level was the best predictor of 24-hour urinary magnesium excretion and FEMg. Serum magnesium levels correlated inversely with tacrolimus concentrations and creatinine clearance. CONCLUSION: Hypomagnesemia in renal transplant recipients results from renal magnesium wasting. Tacrolimus levels and renal function impact on the excess renal magnesium excretion. Studies of longer duration are warranted to assess the long-term effects of this early posttransplant hypomagnesemia.     

Hemodynamic stability during 17 years of the Carpentier-Edwards aortic pericardial bioprosthesis

BACKGROUND: Long-term stability of the hemodynamic performance of commercially available Carpentier-Edwards stented bovine pericardial aortic bioprostheses (Perimount RSR) is unknown. To anticipate the fate of this bioprosthesis, we examined its hemodynamic performance up to 17 years using echocardiographic studies in a Premarket Approval cohort. METHODS: Of 267 patients at four institutions in the Premarket Approval cohort, 85 had a total of 168 echocardiographic studies during a 17-year period of yearly follow-up examinations. These were reviewed and quantified in a core echocardiographic facility. Longitudinal data analysis was used to account for repeated, censored data. RESULTS: Mean transvalvular gradient was inversely related to prosthesis size (p = 0.01), and possibly (p = 0.06) increased somewhat during the first 10 years of follow-up, then stabilized. Effective orifice area was larger in larger valve sizes (p = 0.01), declined somewhat during the first 10 years, and then began to increase again. Ejection fraction declined minimally (p = 0.2). In contrast to the rather stable hemodynamics, aortic regurgitation steadily increased from none to 1 to 2+ (p = 0.005), but rarely (< 10% at 17 years) progressed to 3+ or 4+. CONCLUSIONS: The Carpentier-Edwards aortic pericardial bioprosthesis can be anticipated to have an acceptable long-term transvalvular gradient and effective orifice size that will change trivially up to 17 years after implantation. Mild aortic regurgitation will develop progressively. This anticipated hemodynamic resilience supports continued clinical use of the Perimount Carpentier-Edwards bovine pericardial stented bioprosthesis.     

Cannulation of the axillary artery with a side graft reduces morbidity

BACKGROUND: The axillary artery is our preferred arterial cannulation site when the ascending aorta cannot be cannulated. Previously, we cannulated the artery directly; now we use a side graft. The purposes of this study were to (1) investigate cannulation-related morbidity and (2) determine whether use of a side graft reduces it. METHODS: From January 1993 to January 2001, 392 patients underwent 399 axillary artery cannulations. Indications included calcified ascending aorta (129, 32%), ascending aortic aneurysm (115, 29%), type I aortic dissection (85, 21%), cardiac reoperation (70, 18%), and calcified femoral artery (26, 6%). The axillary artery was cannulated directly in 212 (53%) and with a side graft in 187 (47%). Comparisons of cannulation-related morbidity between the direct cannulation and side graft groups were made overall and after both adjusting and matching for propensity score. RESULTS: Cannulation-related morbidity was infrequent, with brachial plexus injury in 7 (1.8%), axillary artery damage in 7 (1.8%), aortic dissection in 3 (0.8%), and arm ischemia in 3 (0.8%). Only 4 of 187 (2.1%) occurred in the side graft group, versus 16 of 212 (7.0%) with direct cannulation (p = 0.03). After propensity adjustment, the odds ratio for reduction of risk of cannulation-related morbidity with use of a side graft was 0.15 (p = 0.002). CONCLUSIONS: Use of the axillary artery as inflow for cardiopulmonary bypass is associated with low morbidity. However, cannulation with a side graft was associated with less cannulation-related morbidity than direct cannulation. Routine use of a side graft is recommended whenever axillary artery cannulation is indicated.     

Ultrasound-guided percutaneous release of the annular pulley in trigger digit

The purpose of this study was to describe and evaluate a new technique for ultrasound-guided percutaneous release of the annular pulley in trigger digit using a modified hypodermic needle. A total of 35 ultrasound-guided percutaneous releases were performed on 25 patients diagnosed and referred by hand surgeons in our institution over 16 months from October 2006. Inclusion criteria were as follows: adulthood, triggering present for at least 4 months, failure to respond to conservative management or steroid injections, no previous history of pulley release in the affected digit. Under ultrasound guidance, the affected pulley was released using a standard 19-gauge hypodermic needle bent at two points as the cutting device. Follow-up took place at 12 weeks and 6 months with improvement in triggering and clinically graded pain. At follow-up, no complications had occurred and all patients demonstrated improvement in their triggering, with complete resolution in 32 digits (91%), good improvement in 2 digits (6%) and some improvement in 1 digit (3%). This new technique uses a widely available and safe cutting device and is safe and can be used to provide definitive management for trigger finger, allowing the procedure to be performed in a variety of clinical settings.     

Impact of two different models on influenza and pneumococcal vaccination in hospitalized patients

OBJECTIVE: The Centers for Disease Control (CDC) recommends trivalent influenza (TIV) and pneumococcal (PPV) vaccination for eligible hospitalized patients. We conducted a retrospective study comparing two different methods of assessment and its impact on TIV and PPV vaccination in hospitalized patients. DESIGN: Two sequential models were compared in a community hospital for assessing patients' vaccination status and eligibility for TIV and PPV in an inpatient setting. In the first model (Model I), physicians were responsible for assessing eligibility and ordering TIV and/or PPV. In the second model (Model II), nurses were responsible for assessment and vaccination of eligible patients. Charts of hospitalized patients were randomly analyzed for completion rates of the assessment form, rate of vaccination, and documentation of the reason for not vaccinating eligible patients. RESULTS: A total of 138 charts were analyzed for Model I and 168 charts were analyzed for Model II. A significantly higher completion rate for assessment was noted for Model II compared with Model I (79.16% versus 34.78%, P < 0.001 for TIV; 72.02% versus 33.33%, P < 0.001 for PPV). Hospital vaccination rates were not significantly different between the two models for TIV (P = 0.625) and PPV (P = 0.689). A significant percentage of patients refused PPV in Model II [8.03% versus Model I at 3.2% (P = 0.04)]. CONCLUSION: A standing order protocol for assessing hospitalized patients' vaccination status by nursing staff and allowing them to vaccinate eligible patients without depending upon a physician order significantly improved the assessment compliance rate, but not the vaccination rates. Our findings suggest that a system-based method with nursing assessing the need for vaccination and a physician ordering the vaccination would probably have a higher potential for success.     

Defibrillation coil reversal: a rare cause of abnormal noise and inappropriate shocks

We report a rare case of inadvertent reversal of the defibrillator shock coils during generator change which then resulted in both intermittent, recurrent "noise" on both the rate sensing and the shock electrogram leads and multiple inappropriate shocks.     

Histological characterization and development of mesial surface sulci in the human brain at 13–15 gestational weeks through high-resolution histology

Cellular-level anatomical data from early fetal brain are sparse yet critical to the understanding of neurodevelopmental disorders. We characterize the organization of the human cerebral cortex between 13 and 15 gestational weeks using high-resolution whole-brain histological data sets complimented with multimodal imaging. We observed the heretofore underrecognized, reproducible presence of infolds on the mesial surface of the cerebral hemispheres. Of note at this stage, when most of the cerebrum is occupied by lateral ventricles and the corpus callosum is incompletely developed, we postulate that these mesial infolds represent the primordial stage of cingulate, callosal, and calcarine sulci, features of mesial cortical development. Our observations are based on the multimodal approach and further include histological three-dimensional reconstruction that highlights the importance of the plane of sectioning. We describe the laminar organization of the developing cortical mantle, including these infolds from the marginal to ventricular zone, with Nissl, hematoxylin and eosin, and glial fibrillary acidic protein (GFAP) immunohistochemistry. Despite the absence of major sulci on the dorsal surface, the boundaries among the orbital, frontal, parietal, and occipital cortex were very well demarcated, primarily by the cytoarchitecture differences in the organization of the subplate (SP) and intermediate zone (IZ) in these locations. The parietal region has the thickest cortical plate (CP), SP, and IZ, whereas the orbital region shows the thinnest CP and reveals an extra cell-sparse layer above the bilaminar SP. The subcortical structures show intensely GFAP-immunolabeled soma, absent in the cerebral mantle. Our findings establish a normative neurodevelopment baseline at the early stage.