Pulmonary sarcoidosis in a 14-year-old boy diagnosed by low-dose CT-guided transthoracic lung biopsy

Pulmonary sarcoidosis is a rare disease in the pediatric age group, characterized by the presence of epitheloid-cell granulomas. In stage 3 sarcoidosis, pulmonary infiltrates without hilar lymphadenopathy occur. Definitive diagnosis requires a histopathological specimen, which might be difficult to obtain by transbronchial biopsy. Multidetector computed tomography (MDCT)-guided transthoracic lung biopsy (TLB) is a well-established procedure in adults, but has only rarely been applied in children.A 14-year-old boy was admitted to hospital for evaluation of a chronic systemic disease with severe pulmonary manifestation. All investigations, including bronchosopy and bronchoalveolar lavage with microbiological and virological testing, had been negative. MDCT-guided TLB was performed on a 16-section scanner with a low-dose protocol (single slices, 120 kV, 20 mAs), using a 16-gauge biopsy device. The total effective dose was 0.4 mSv for the biopsy procedure. Histopathological examination revealed multiple epitheloid-cell granulomas with giant cells in the absence of microbiological or virological abnormalities. A diagnosis of stage 3 pulmonary sarcoidosis was made and systemic anti-inflammatory therapy was administered, which led to complete remission within weeks. MDCT-guided TLB can be a valuable instrument in assessing pulmonary manifestations of pediatric sarcoidosis, enabling precise histopathological diagnosis and adequate therapy. The use of low-dose protocols can substantially reduce radiation exposure without relevant loss of image information. MDCT-guided lung biopsy should be considered prior to open-lung surgery in selected patients with unclear pulmonary disease.

Initiale Ergebnisse der Schulter-MRT in Außenrotation bei primärer Schulterluxation und nach Ruhigstellung in Außenrotation

PURPOSE

A change in the strategy for treating primary anterior traumatic dislocation of the shoulder has occurred. To date, brief fixation of internal rotation via a Gilchrist bandage has been used. Depending on the patient's age, a redislocation is seen in up to 90 % of cases. This is due to healing of the internally rotated labrum-ligament tear in an incorrect position. In the case of external rotation of the humerus, better repositioning of the labrum ligament complex is achieved. Using MRI of the shoulder in external rotation, the extent of the improved labrum-ligament adjustment can be documented, and the indication of immobilization of the shoulder in external rotation can be derived. The aim of this investigation is to describe the degree of position changing of the labrum-ligament tear in internal und external rotation.

MATERIALS AND METHODS

10 patients (9 male, 1 female, mean age 30.4 years, range 15 - 43 years) with a primary anterior dislocation of the shoulder without hyper laxity of the contra lateral side and labrum-ligament lesion substantiated by MRI were investigated using a standard shoulder MRI protocol (PD-TSE axial fs, PD-TSE coronar fs, T2-TSE sagittal, T1-TSE coronar) by an axial PD-TSE sequence in internal and external rotation. The dislocation and separation of the anterior labrum-ligament complex were measured. The shoulders were immobilized in 10 degrees external rotation for 3 weeks. After 6 weeks a shoulder MRI in internal rotation was performed.

RESULTS

In all patients there was a significantly better position of the labrum-ligament complex of the inferior rim in external rotation, because of the tension of the ventral capsule and the subscapular muscle. In the initial investigation, the separation of the labrum-ligament complex in internal rotation was 0.44 +/- 0.27 mm and the dislocation was 0.45 +/- 0.33 mm. In external rotation the separation was 0.01 +/- 0.19 mm and the dislocation was - 0.08 +/- 0.28 mm. After 6 weeks of immobilization in 10 degrees external rotation, the separation of the labrum was - 0.10 +/- 0.14 mm and the dislocation was - 0.23 +/- 0.21 mm.

CONCLUSION

In anterior labrum-ligament tears, the axial MRI of the shoulder in external rotation demonstrates a more physiologic position of the glenoid. This may indicate an immobilization of the shoulder in external rotation, which results in a more anatomical healing of the glenoidal tear. Thus, in the case of labrum-ligament tears, MRI in external rotation is becoming indispensable.

Mitochondrial phylogeny of African wood mice, genus Hylomyscus (Rodentia, Muridae): implications for their taxonomy and biogeography

This paper investigates the usefulness of two mitochondrial genes (16S rRNA and cytochrome b) to solve taxonomical difficulties within the genus Hylomyscus and to infer its evolutionary history. Both genes proved to be suitable molecular markers for diagnosis of Hylomyscus species. Nevertheless the resolving powers of these two genes differ, and with both markers (either analyzed singly or in combination), some nodes remain unresolved. This is probably related to the fact that the species emerged during a rapid diversification event that occurred 2-6 Myr ago (4-5 Myr ago for most divergence events). Our molecular data support the recognition of an "aeta" group, while the "alleni" and "parvus" groups are not fully supported. Based on tree topology and genetic divergence, two taxa generally recognized as subspecies should be elevated at the species level (H. simus and H. cf kaimosae). H. stella populations exhibit ancient haplotype segregation that may represent currently unrecognized allopatric species. The existence of cryptic species within H. parvus is questioned. Finally, three potentially new species may occur in West Central Africa. The Congo and Oubangui Rivers, as well as the Volta and Niger Rivers and/or the Dahomey gap could have formed effective barriers to Hylomyscus species dispersal, favoring their speciation in allopatry. The pronounced shifts in African climate during the late Pliocene and Miocene, which resulted in major changes in the distribution and composition of the vegetation, could have promoted speciation within the genus (refuge theory). Future reports should focus on the geographic distribution of Hylomyscus species in order to get a better understanding of the evolutionary history of the genus.

Anwendung der 16-Zeilen-Mehrdetektor-CT in der Initialdiagnostik beim Polytrauma: Eine Zeitanalyse

PURPOSE

Description and time analysis of a 16-row MDCT protocol in the evaluation of multiple trauma patients considering transport, time of scanning, patient positioning, image reconstruction, and image interpretation.

MATERIALS AND METHODS

Between May and December 2004, 60 multiple trauma patients underwent 16-row MDCT (Sensation, Siemens, Erlangen, Germany). The protocol included serial scanning of the head, spiral scanning of the cervical spine and contrast-enhanced spiral scanning of the thorax/abdomen with multiplanar reformations (MPR) of the thoracic/lumbar spine and the pelvis. All time intervals including transport, patient positioning, scanning, duration of MPR, total time in the examination room, and time to first and final image interpretation were prospectively evaluated. Furthermore, patient characteristics, trauma profiles, and mortality rates were recorded.

RESULTS

46 male and 14 female patients (mean age 43.6 years) were enrolled in the study. Time analysis of 16-row MDCT revealed the following results (mean time standard deviation): Emergency room treatment and transport 19.2 +/- 6.7 min, patient positioning 16.5 +/- 6.5 min, scan duration 8.0 +/- 3.3 min, total time in examination room 24.5 +/- 7.2 min, image reconstruction including MPR 32.0 +/- 16.4 min, and time of first (16.4 +/- 4.7 min) and final image interpretation (82.5 +/- 30.4 min). Trauma profiles revealed thoracic injuries in 35/60 patients (58.3 %), head injuries in 23/60 patients (38.3 %), abdominal injuries in 15/60 patients (25.0 %), injuries of the cervical (9/60 patients, 15.0 %), thoracic (12/60 patients, 20.0 %), and lumbar spine (19/60 patients, 31.7 %), pelvic injuries in 13/60 patients (21.7 %), and injuries of extremities in 39/60 patients (65.0 %). The mortality rate was 21.7 %.

CONCLUSION

MDCT provides fast and all-inclusive imaging of multiple trauma patients. With the use of 16-row MDCT technology scanning times of 8 minutes are realistic and first image interpretation can be performed 16 minutes after arrival of the patient in the examination room and 35 minutes after admission in the emergency room, respectively. The duration of all procedures done in the examination room is strongly influenced by positioning maneuvers, whereas final image interpretation depends on image reconstructions including MPR. Beside technical improvements, these circumstances provide the potential to further accelerate the diagnostic process in multiple trauma victims.

Stent-Implantationsplanung bei tumor-assoziierter, brochoskopisch nicht passierbarer Trachealstenose - Eine Indikation für die virtuelle CT-Bronchoskopie

We report about a male 50-year-old patient with known non-small cell lung cancer and tumor-associated stenosis of the right main bronchus already treated with Neodym-YAG-laser coagulation. Eight months later the patient was readmitted to hospital and revealed complete occlusion of the right main bronchus and subtotal stenosis of the distal trachea and the left main bronchus. Conventional tracheobronchoscopy failed to visualize the post-stenotic parts of the left main bronchus due to the length and degree of stenosis. Multidetector-CT-generated virtual tracheobronchoscopy was able to demonstrate complete intraluminal tumor extent thus making precise pre-interventional measurements for stent implantation possible. Furthermore, post-interventional re-evaluation by virtual tracheobronchoscopy confirmed correct position and patency of the stent located within the distal trachea and the left main bronchus. Our case report demonstrates a non-invasive and easy approach for evaluating the tracheobronchial system in a patient with tumor-associated airway stenosis including the possibility for viewing beyond post-stenotic segments.

A relevant in vitro rat model for the evaluation of blood-brain barrier translocation of nanoparticles

Poly(MePEG2000cyanoacrylate-co-hexadecylcyanoacrylate) (PEG-PHDCA) nanoparticles have demonstrated their capacity to reach the rat central nervous system after intravenous injection. For insight into the transport of colloidal systems across the blood-brain barrier (BBB), we developed a relevant in vitro rat BBB model consisting of a coculture of rat brain endothelial cells (RBECs) and rat astrocytes. The RBECs used in our model displayed and retained structural characteristics of brain endothelial cells, such as expression of P-glycoprotein, occludin and ZO-1, and immunofluorescence studies showed the specific localization of occludin and ZO1. The high values of transendothelial electrical resistance and low permeability coefficients of marker molecules demonstrated the functionality of this model. The comparative passage of polyhexadecylcyanoacrylate and PEG-PHDCA nanoparticles through this model was investigated, showing a higher passage of PEGylated nanoparticles, presumably by endocytosis. This result was confirmed by confocal microscopy. Thanks to a good in vitro/in vivo correlation, this rat BBB model will help in understanding the mechanisms of nanoparticle translocation and in designing new types of colloidal carriers as brain delivery systems.

[Feasibilities and bounds of diagnostic radiology in case of back pain]

Chronic monotone back pain is no pressing indication for radiographic procedures, but chronic progressive or symptomatic back pain should be investigated by radiographic means. Beneath conventional radiology and computed tomography (CT) magnetic resonance imaging (MRI) has become a more method of standard in these cases. The radiographic investigation of back pain is shown in cases of discal and vertebral degeneration and spondylitis. Typical signs and differential diagnosis are demonstrated. After demonstration of radiological means. After introduction and valuation of radiological means, as conventional radiography, CT, MRI, myelography and scintigraphy, it is entered into degenerative changes and degenerative diseases of vertebra endplates and vertebra bodies as a reason of pain. Reasons of spinal stenosis are discussed. In case of inflammatory changes, bacterial inflammation of vertebrae and intervertebral joints are represented. Changes of spondylodiscitis/spondylitis are opposed to inflammatory changes of Morbus Bechterew and Morbus Scheuermann.

[Prospective randomized trial of a modified standard multislice CT protocol for the evaluation of multiple trauma patients]

PURPOSE

To evaluate whether modification of a standard multislice CT (MSCT) protocol might improve the diagnostic work flow in patients with multiple trauma without relevant loss of image quality.

MATERIALS AND METHODS

Between September 2002 and September 2003, 80 multiple trauma patients underwent 4-slice CT encompassing head, thorax, abdomen/pelvis and spine. All patients were randomly assigned to either protocol A or B: Protocol A included serial scanning of the head (collimation 1 mm, 350/380 mAs/120 kV) and spiral scans of thorax, abdomen/pelvis and spine (collimation 2.5 mm, 220 mAs/120 kV) with gantry angulation and arm elevation; protocol B included spiral scanning of all body regions (collimation 2.5 mm, 300/150 mAs/120 kV) without gantry angulation or arm elevation. Time intervals, radiation exposure and results of the initial and final analysis were documented.

RESULTS

In the investigated 64 male and 16 female patients (mean age 41.7 years), 88.7 % of the 407 pathologic findings were correctly identified on the initial images. Protocol B revealed a significant decrease in scan time (6.4 vs. 16.8 min., p < 0.001), time in the CT examination room (22.9 vs. 32.8 min.; p < 0.001), time until initial (25.3 vs. 35.8 min.; p < 0.001) and final image analysis (93.7 vs. 112.9 min; p < 0.005). No significant difference was found for patient transport time and image reconstruction time. Protocol B has a significantly lower effective radiation dose compared to protocol A (10.2 vs. 12.7 mSv, p < 0.001).

CONCLUSIONS

Applying a modified MSCT protocol without gantry angulation and arm elevation can significantly decrease radiation exposure and examination time in multiple trauma patients without relevant loss of diagnostic image information and, consequently, has the potential of improving the diagnostic process and prognosis in multiple trauma patients.

Amoebae in domestic water systems: resistance to disinfection treatments and implication in Legionella persistence

AIMS

Monitoring of microbial changes during and after application of various disinfection treatments in a model domestic water system.

METHODS AND RESULTS

A pilot-scale domestic water system consisting of seven galvanized steel re-circulation loops and copper dead legs was constructed. Culture techniques, confocal laser scanning microscopy after fluorescent in situ hybridization and viability staining with the BacLight LIVE/DEAD kit were used for planktonic and biofilm flora monitoring. Before starting the treatments, the system was highly contaminated with Legionella pneumophila and biofilm populations mainly consisted of beta-proteobacteria. In the water and the biofilm of the loops, continuous application of chlorine dioxide (0.5 mg l(-1)), or chlorine (2.5 mg l(-1)) were very effective in reducing the microbial flora, including L. pneumophila. Heterotrophic bacteria, although strongly reduced, were still detectable after ozone application (0.5 mg l(-1)), whereas with monochloramine (0.5 mg l(-1)) and copper-silver ionization (0.8/0.02 mg l(-1)), the contamination remained significantly higher. Monochloramine and copper-silver did not remove the biofilm. During copper-silver application, Legionella re-growth was observed. Only chlorine dioxide led to detectable effects in the dead leg. Amoebae could not be eliminated, and after interrupting the treatments, L. pneumophila quickly recovered their initial levels, in all cases.

CONCLUSIONS

Chlorine dioxide, applied as a continuous treatment, was identified in this study as the most efficient for controlling L. pneumophila in a domestic water system. Chlorine dioxide showed a longer residual activity, leading to improved performance in the dead leg. Amoebae resisted to all the treatments applied and probably acted as reservoirs for L. pneumophila, allowing a quick re-colonization of the system once the treatments were interrupted.

SIGNIFICANCE AND IMPACT OF THE STUDY

Control of microbial contamination requires maintenance of a constant disinfectant residual throughout the water system. Treatment strategies targeting free-living amoebae should lead to improved control of L. pneumophila. Such treatment strategies still have to be investigated.

[Visual cortex in the Tolosa-Hunt syndrome. Functional imaging for the detection of a psychogenic disorder--a case report]

Besides painful ophthalmoplegia, patients suffering from Tolosa-Hunt syndrome often present increasing loss of visual perception. The impairment of the optic nerve leads to a delay of the VEP (visual evoked potentials) responses. Using the method of magnetic resonance imaging (MRI), some patients present unspecific alterations in the vicinity of the optic nerve. However, both methods (VEP and MRI) are unsuitable to assess the effect of an impaired optic nerve function on neuronal processing in the visual cortex. We report one patient suffering from Tolosa-Hunt syndrome affecting the optic nerve. We used fMRI (functional magnetic resonance imaging) to show how this impairment of the optic nerve alters cortical processing of visual information. The activity of the unaffected visual cortex was bilaterally reduced when compared to healthy volunteers but greater that obtained from patients suffering from bilateral occipital infarction. Our results offer new opportunities to assess the efficiency of therapy in patients with increasing loss of visual perception due to the Tolosa-Hunt syndrome. Further studies are necessary to investigate, whether fMRI also provides the possibility to assess the efficiency of drug therapy on optic nerve function.

[Misdiagnosis of a Leiomyosarcoma of the inferior vena cava as a renal cell carcinoma]

Leiomyosarcoma of the vena cava inferior (VCI) is a rare mesenchymal malignant tumor of the retroperitoneum. About 200 cases have been described in the literature so far. Leiomyosarcomas may resemble other tumors including renal cell carcinoma, adrenal carcinoma, and hepatic adenoma. Thus, misinterpretation of a leiomyosarcoma of the VCI is a common problem. We present a 71-year-old female with a large subhepatic, retroperitoneal tumorous mass which was diagnosed to be a renal cell carcinoma by sonography and computed tomography. After application of magnetic resonance imaging and retrospective analysis of the CT scan, diagnosis could be revised. Laparotomy and en bloc resection of the tumor was performed; histopathological examination confirmed a leiomyosarcoma of the VCI. The postoperative course was unremarkable. Leiomyosarcoma of the VCI may resemble advanced stages of renal cell carcinoma. High-resolution imaging modalities (computed tomography, magnetic resonance imaging) are able to precisely evaluate the typical imaging characteristics of leiomyosarcomas, thus determining correct diagnosis in affected patients. This is essential for successful operative therapy.