Surgical management of duodenal injuries in children

BACKGROUND: The goal of this study was to review current injury characteristics, severity, intervention, and outcome of duodenal injuries from a single, pediatric trauma facility. METHODS: A retrospective review was performed of duodenal injuries in children less than 16 years of age from 1990 to 2000. RESULTS: Twelve children had duodenal injuries as a result of blunt abdominal trauma. Six injuries were the result of motor vehicle crashes. Nonaccidental trauma (2) and contact injury (4) provided the remaining cases. Diagnosis was achieved by abdominal computed tomography. Severity of duodenal injury included grade I (1), II (8), and III (3). Seven patients had associated visceral or neurologic injuries. Average Injury Severity Score was 18. Duodenal repair was required in 9 of the 10 patients explored. Treatment included observation (3); primary repair, alone, (2) or with proximal decompression (4); and pyloric exclusion with gastrojejunostomy (3). Exclusion techniques had fewer complications (0% vs 57%) and fewer hospital days (19 vs 23). CONCLUSIONS: Blunt abdominal trauma remains the most prevalent mechanism for pediatric duodenal injuries. Patients undergoing pyloric exclusion for severe duodenal trauma had a lesser morbidity and a shorter hospital stay in this small series. Pyloric exclusion remains an alternative for the treatment of severe duodenal injuries in selected children.     

Initial in vivo results of the new Medtronic Advantage(TM) bileaflet valve in aortic position and comparison to the SJM

The present study investigated the Medtronic Advantage (MA) bileaflet valve in an animal model and compared the results to the St. Jude Medical (SJM) valve. Systolic performance and coronary artery flow in different orientations were studied.A rotation device holding either a MA or SJM aortic valve size 23 mm was implanted into eight pigs. Transvalvular pressure gradients and ventricular dimensions were investigated with the valves in different orientations. Coronary artery flow was measured at normal and high cardiac output.Orientation significantly influenced the hemodynamic performance of both valves. The best results for both valves were obtained with one orifice proximal to the right cusp. Pressure gradients and ventricular dimensions of the MA corresponded to the SJM. Coronary artery flow was higher for the MA.The systolic performance of the new MA bileaflet valve was similar to the SJM. During diastole, the MA showed significantly higher LAD coronary flow.     

Diagnostic accuracy of ultrasound, 18F-FDG-PET/CT,and fused 18F-FDG-PET-MR images with DWI for the detection of cervical lymph node metastases of HNSCC

Objective

This study aimed to compare ¹⁸F-fluorodesoxyglucose positron emission tomography/MRI (¹⁸F-FDG-PET-MRI) fusion images, including diffusion-weighted imaging (DWI), ¹⁸F-FDG-PET/CT, and ultrasound (US) regarding their performance in nodal staging of patients with head and neck squamous cell carcinoma (HNSCC).

Materials and methods

Eighteen patients prospectively underwent ultrasound examination, ¹⁸F-FDG- PET/CT, and MRI before oral tumor resection and bilateral neck dissection. PET data sets were fused with contrast-enhanced T1-weighted MR images. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for nodal detection were calculated for all the imaging modalities. Furthermore, the accuracy of the correct N-staging was calculated for all methods. Detailed histopathology served as the standard of reference.

Results

The sensitivity, specificity, PPV, NPV, and accuracy for detection of lymph node metastases were 63, 99, 86, 96, and 95 % for ultrasound; 30, 97, 56, 92, and 90 % for ¹⁸F-FDG-PET/CT; 52, 96, 59, 94, and 91 % for ¹⁸F-FDG-PET-MRI; and 53, 97, 67, 95, and 92 % for ¹⁸F-FDG-PET-MRI plus DWI, respectively. There was no significant difference in the diagnostic accuracy for lymph node metastasis detection between ¹⁸F-FDG-PET-MRI and ¹⁸F-FDG-PET/CT (p?=?0.839) and between ¹⁸F-FDG-PET-MRI plus DWI and ¹⁸F-FDG-PET/CT (p?=?0.286), respectively. US was significantly more accurate than ¹⁸F-FDG-PET/CT (p?=?0.009), whereas no significant difference was seen between ¹⁸F-FDG-PET-MRI and US (p?=?0.223) or ¹⁸F-FDG-PET-MRI plus DWI and US (p?=?0.115). The nodal stage was correctly rated by ¹⁸F-FDG-PET-MRI in eight patients, ¹⁸F-FDG-PET-MRI plus DWI in nine patients, US in 12 patients, and ¹⁸F-FDG-PET/CT in five out of 18 patients.

Conclusion

Software-based fusion of ¹⁸F-FDG-PET-MRI and ¹⁸F-FDG-PET-MRI plus DWI may not increase nodal detection and N-staging performance in patients with oral malignancies compared to US and ¹⁸F-FDG-PET/CT.

Clinical relevance

Surgical staging of cervical lymph nodes will not be replaced even by advanced imaging modalities in the near future.     

Pediatric pancreatic trauma: predictors of nonoperative management failure and associated outcomes

Background

Nonoperative management (NOM) is an accepted treatment of pediatric solid organ injuries and is typically successful. Blunt pancreatic trauma tends to require operative intervention more frequently. We sought to identify predictors of failure of NOM and compare the outcome of operative management against NOM.

Methods

A retrospective analysis was performed from January 1993 to December 2002 of all children with blunt pancreatic injuries from the trauma registries of 7 designated level 1 pediatric trauma centers. Failure of NOM was defined as the need for intraabdominal operative intervention. Injuries were graded I to V, and ductal injury was defined as grades III to V. Parameters included mechanism of injury, injury severity score (ISS), organ grade, Glasgow Coma Scale score, and outcome. Data were analyzed by Fisher exact test and Mann-Whitney U test, with mean values ± SD and significance of P < .05.

Results

Pancreatic injuries were present in 173 (9.2%) of 1823 patients. Of these, 43 (26.0% [43/173]) required an operation. Valid morbidity data was obtained in 118 of 173 patients. ISS was significantly higher in all patients treated operatively. Patients with an injury of grade III to V failed NOM more frequently than all patients with pancreatic injury (P =.0169). Length of stay was longer, and the incidence of pseudocysts, drainage procedures, and pancreatitis was higher in NOM patients, although not significant.

Conclusions

Patients with pancreatic injuries had a NOM failure rate of 26.0%. ISS and injury grades III to V were predictors of NOM failure. Patients with pancreatic ductal injury require more aggressive management.     

Main branch stenosis following aortic valve replacement

Three patients developed left main stem stenosis within some months after aortic valve replacement. In all of them diagnosis was confirmed by angiography and bypass surgery was performed successfully. Left main stem stenosis is a rare complication of aortic valve replacement and is due to cannulation and perfusion of the coronary arteries. The mechanism is probably injury of the vessel wall due to the perfusion-catheter, followed by intimal hyperplasia. A similar mechanism is assumed for restenosis after transluminal coronary angioplasty.     

Rupture of the spleen by penetration of pancreatic pseudocysts

2 patients with known chronic recurrent pancreatitis and proven pancreatic pseudocysts in the tail of the pancreas developed a pseudocystic invasion of the spleen followed by tryptic erosion of it. This complication, previously seldom reported, occurred twice in one year, the diagnosis being achieved by CT.     

Intrarenal Doppler ultrasonography: which vessel should be investigated?

The aim of our study was to determine whether the site of intrarenal Doppler measurement influences diagnosis of renal artery stenosis. In an experimental test, three sheep with variable degrees of renal artery stenosis were investigated. In each animal, the resistive index from renal segmental arteries correlated better with mean pressure gradient (r = 0.85, 0.71, 0.85) and had lower standard deviation (s = 0.02 to 0.05) than resistive index from interlobar arteries (r = 0.48, 0.54, 0.61) (s = 0.03 to 0.11). In two animals the difference was significant (correlation: P < or = 0.01, P = 0.13, P < or = 0.05; standard deviation: P < or = 0.01, P < or = 0.34, P < or = 0.05). For detecting renal artery stenosis, vessels within the renal sinus should be used for Doppler sampling.     

Physiological effects of chronic and acute application of N-methyl-D-aspartate and 5-amino-phosphonovaleric acid to the optic tectum of Rana pipiens frogs.

Visually elicited activity contributes to the formation of orderly connections in the optic tectum of frogs. Glutamate receptors of the N-methyl-D-aspartate class participate in this process. Blocking those receptors interferes with activity-dependent refinement of maps in normal frogs and of ocular dominance bands in surgically produced animals with three eyes. Chronic application of N-methyl-D-aspartate sharpens the bands. The possibility that 5-amino-phosphonovaleric acid depresses tectal responsiveness was motivation for studying the effects of 5-amino-phosphonovaleric acid and N-methyl-D-aspartate applied both chronically and acutely. We evaluated tectal responsiveness to visual input by presenting flashes of light to one eye and recording responses in the ipsilateral tectal lobe. This method reveals the output of the tectal cells contralateral to the stimulated eye. These cells project via the nucleus isthmi to the opposite tectal lobe. We also mapped the receptive field dimensions of the crossed isthmotectal axons. Our results show that acute topical application of 500 microM or 1 mM N-methyl-D-aspartate dramatically increases spontaneous activity, while 100 microM N-methyl-D-aspartate causes little change. Chronic treatment with N-methyl-D-aspartate at a low dose (estimated to be in the micromolar range) shown to influence retinotectal mapping, reduces response latencies but produces no statistically significant changes in tectal cell firing rates or receptive field size. Acute application of 5-amino-phosphonovaleric acid produces complex results: 10 microM produces no changes in firing, 100 microM 5-amino-phosphonovaleric acid decreases firing, and doses of 500-100 microM increase the firing.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemmung des Carrageenan-induzierten entzündlichen Rattenpfotenödems durch systemische Applikation von Rattenfibrinogen und -fibrinopeptiden

Summary The acute inflammatory rat paw oedema induced by subplantar injection of carrageenan was significantly inhibited by intraperitoneal injection of rat fibrinogen, intraperitoneal and intracardial injection of fibrinopeptides A and B. In contrast the fibrin split products derived from plasmin digestion proved to be ineffective.

     

Renal factors in juvenile hypertension

Summary Essential hypertension in infancy, once believed to occur rarely if ever, is now increasingly recognized as a potential precursor of essential hypertension in adulthood. The mechanisms responsible for hypertension in childhood and adolescence are only beginning to be delineated. Renal factors assumed to be operative in juvenile hypertension are involving either volume control (by renal regulation of sodium-chloride and water balance) or vasoactive substances like the kallikrein-kinin, the renin-angiotensin and the prostaglandin system and other less well defined hormones. There is a close interrelationship of all these hormones with each other as well as a close linking of these vasoactive compounds to the renal regulation of sodium-chloride and water balance, thus interfering with a major environmental factor necessary for the development of essential hypertension. At present, data are insufficient to delineate a single hormone or a single hemodynamic abnormality as the only primary factor in juvenile hypertension. Further research into the pathomechanisms responsible for the elevation of blood pressure at its very beginning will improve our understanding of hypertension and possibly benefit its management by early intervention.Supported by Deutsche Forschungsgemeinschaft