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71.

Clinical/methodical issue

Imaging plays an essential role in the therapeutic management of cancer of unknown primary (CUP) patients for localizing the primary tumor, for the identification of tumor entities for which a dedicated therapy regimen is available and for the characterization of clinicopathological subentities that direct the subsequent diagnostic and therapeutic strategy.

Standard radiological methods

Modalities include conventional x-ray, computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound as well as positron emission tomography (PET)-CT and MRI-PET.

Performance

In whole body imaging CT has a high sensitivity for tumor entities which frequently present as a metastasized cancer illness. According to the current literature CT is diagnostic in 86% of patients with pancreatic carcinoma, in 36% of patients with colon carcinoma and in 74% of patients with lung carcinoma. Additionally a meta-analysis showed that for patients with squamous cell carcinoma and cervical lymph node metastases a positive diagnosis was possible in 22% of the cases using CT, in 36% using MRI and in 28-57% using 18F-fluorodeoxyglucose PET-CT (18F-FDG PET-CT). In addition, MRI plays an important role in the localization of primary occult tumors (e.g. breast and prostate) because of its high soft tissue contrast and options for functional imaging.

Achievements

At the beginning of the diagnostic algorithm stands the search for a possible primary tumor and CT of the neck, thorax and abdomen is most frequently used for whole body staging. Subsequent organ-specific imaging examinations follow, e.g. mammography in women with axillary lymphadenopathy. For histological and immunohistochemical characterization of tumor tissue, imaging is also applied to identify the most accessible and representative tumor manifestation for biopsy. Tumor biopsy may be guided by CT, MRI or ultrasound and MRI also plays a central role in the localization of primary occult tumors because of superior soft tissue contrast and options for functional imaging (perfusion, diffusion), e.g. investigation of breast carcinoma or prostate carcinoma.

Practical recommendations

Whole body staging stands at the beginning of the diagnostic algorithm in CUP syndrome to localize a potential primary tumor. Clinically, contrast-enhanced CT of the neck, thorax and abdomen is frequently applied; however, many studies have demonstrated augmented sensitivity of 18F-FDG PET-CT for the detection of primary tumors and metastatic tumor manifestations.  相似文献   
72.
Correct histopathologic diagnosis is essential for adequate treatment of soft tissue sarcomas. Due to the disorder’s rarity, multitude of subgroups, sometimes varying histopathologic appearance, and occasionally inadequate biopsy specimens, diagnosis and grading are challenging. The records of 603 patients with soft tissue tumors of the extremities were reviewed concerning mismatches in primary and definite diagnoses relating to entity, evaluation of primary or recurrent tumor specimens, and the diagnosing pathology institution. For second opinions we referred to the Institute of Pathology of the Ruhr University at the Bergmannsheil Hospital in Bochum, Germany, and to the Pathology Institute of the University of Jena, also in Germany. Liposarcoma and malignant fibrous histiocytoma were the most often diagnosed subgroups at 24% and 22.6%, respectively. In the eight most frequent sarcoma types, malignant peripheral nerve sheath tumors and leiomyosarcoma had the highest rates of false primary diagnosis, 78.4% and 74.2% of cases, respectively. The diagnostic error ratio for nonspecialized pathologists in practice, community hospital pathologists, and academic medical centers was over 60%. For optimal treatment of soft tissue sarcomas, we suggest obtaining expert second opinion to ensure adequate surgical therapy and precise indications for radiation and chemotherapy.  相似文献   
73.

Objective

Lower extremity injuries make up a substantial proportion of the injuries in multiply injured patients. The aim of this systematic literature analysis was to give an overview of the levels of evidence for different management strategies in the first operative phase after long-bone injuries of the lower extremity in multiply injured patients to enable, in the presence of adequate evidence, the development of clinical management corridors or, if the evidence was found to be inadequate, to document the necessity for scientific proof.

Methods

Clinical trials were systematically collected (Medline, Cochrane and hand searches) and classified into evidence levels (EL 1 to 5 according to the Oxford system).

Results

The necessity for primary or secondary definitive osteosynthesis of femur/tibia shaft fractures is still a matter of discussion. Intramedullary nailing is the preferred operative procedure for definitive treatment of femur shaft fractures. Stabilization of proximal and distal femur and tibia fractures is predominantly based on expert opinion. According to the literature, perioperative antibiotic prophylaxis is essential in fracture treatment.

Conclusion

Numerous comparative studies (EL 2) dealing with management strategies in the first operative phase after long-bone injuries of the lower extremity in multiply injured patients are available, but there are only a few randomized studies. Based on the available data, it is possible to develop a rational therapy for this patient population.  相似文献   
74.
Rupture of the Achilles tendon is typically associated with sportive activities with increasing tendency; it occurs most commonly in the third to fourth decade of life with a male-to-female ratio of 5–10:1. Ruptures are caused predominantly by a sudden, unexpected overextension of the tendon while direct trauma is less frequent. The recommended treatment of the injury remains controversial. In Germany, due to the good functional results, the open surgical repair represents the standard therapy since many years. The open suture technique offers the advantage of a lower re-rupture rate but is associated with the risk of wound-related complications including infection. By percutaneous suture techniques a significant decrease in the rate of infections and complications in wound healing could be achieved by minimal-access with reduced soft tissue trauma; on the other hand an increased rate of lesions of the sural nerve is reported. Dynamic imaging assessment of ultrasound or MRI allows a more accurate localisation of the ruptured ends of the tendons which is the prerequisite for the non-operative primary functional treatment of Achilles tendon ruptures. This conservative treatment regime is recommended when adaptation of the ends of the ruptured tendon is possible in 20° plantar flexion of the foot. Moreover, the desired level of daily activity and the patients’ degree of compliance has to be considered. Operative management should be avoided in the elderly patient or patients with risk factors like immunosuppressive therapy, diabetes mellitus, steroid use or failure to comply.  相似文献   
75.
Since the introduction of intraoperative echocardiography into clinical practice in the 1970’s its use and utility in the perioperative period has become increasingly more evident. Especially in patients undergoing cardiac surgical procedures intraoperative echocardiography has gained great diagnostic importance. Intraoperative transesophageal echocardiography (TEE) and epiaortic ultrasound are two important and complementing diagnostic modalities in this patient population. The clinical information obtained with intraoperative TEE in certain cases might have a direct impact on surgical decision-making and therefore may positively influence patient outcome. In patients undergoing non-cardiac surgical procedures, TEE can be a valuable tool in high-risk patients, in patients experiencing hemodynamic instability or in those suffering intraoperative cardiac arrest. Intraoperative TEE might allow a primary diagnosis of the underlying etiology and facilitate the institution of further therapeutic interventions. In addition TEE can be performed during ongoing cardiopulmonary resuscitation and does not interfere with patient management. This review introduces the clinician to the current evidence of the impact of intraoperative echocardiography on intraoperative surgical decisions during surgical procedures. It helps the clinician to identify indications and realize the potential applications of intraoperative echocardiography.  相似文献   
76.
Relevant changes have occurred in disaster management in Germany due to legal alterations and the introduction of the diagnosis-related groups (DRG) system. This has resulted in a reduction in bed capacities and an increase in bed utilization. In addition to the preclinical deployment strategy the provisional aspects of disaster medicine with the problem of the emergency service/hospital interface will be described. A suggestion for a solution for optimization of patient allocation in mass disasters or catastrophes will be demonstrated with the catastrophe network of the German Society for Trauma Surgery (DGU).  相似文献   
77.

Objectives

The use of inhibitors of phosphodiesterase (PDE) isoenzymes 1 and 5 to treat overactive bladder has been suggested. To further evaluate the significance of PDE isoenzymes in detrusor smooth muscle relaxation, we investigated the effects of selective PDE inhibitors on the tension induced by carbachol of isolated human detrusor tissue. Using immunohistochemical methods, the expression of PDE1, PDE4, and PDE5 in human detrusor was also investigated.

Material and Methods

The expression of PDE1, PDE4, and PDE5 was evaluated by means of conventional immunohistochemistry (IHC). Using the organ bath technique, the effects of the PDE inhibitors vinpocetine, rolipram, sildenafil, tadalafil, and vardenafil on the tension induced by the muscarinic agonist carbachol (1 µM) were investigated.

Results

The tension induced by carbachol was dose-dependently reversed by the PDE inhibitors; the maximum reversal of tension ranged from 7% (tadalafil) to 34% (vardenafil). IHC revealed that the expression of PDE isoenzymes was limited to the smooth musculature of the detrusor. While there was prominent expression of PDE4 and PDE5, immunoreactions indicating the presence of PDE1 were less abundant.

Conclusion

Despite the fact that inhibitors of PDE1, PDE4, and PDE5 exerted only a weak relaxant response on detrusor strips precontracted by carbachol, our findings indicate that both the cAMP and cGMP pathways might be involved in the relaxation mechanism of human detrusor smooth muscle.  相似文献   
78.
Magnetic resonance imaging (MRI) has evolved as a powerful tool that has been applied more and more in recent years for the assessment of gastrointestinal structures, owing to its unsurpassed soft tissue contrast, lack of radiation exposure, and implementation of fast scanning techniques. As a virtual endoscopic technique, MR colography (MRC) makes it possible to image inflammatory processes and tumor disease of the large intestine with a high degree of accuracy. In this article we describe current techniques and applications of MRC and give an overview of clinical studies comparing MRC with other diagnostic procedures.  相似文献   
79.
Ankle sprains are one the most common injuries of the lower limb. Fractures, ligamentous lesions, and cartilaginous damage are often associated. Nevertheless the injury is often misjudged and concomitant chondral lesions are assessed late. In the case of a symptomatic osteocartilaginous lesion of the talus, which can be illustrated by MRI or X-ray, operative intervention is indicated. Methods such as microfracturing, mosaicplasty, and autologous chondrocyte transplantation (ACT) are in clinical use. The latter is well known and being established as the treatment of choice for large cartilage defects in the knee. Due to the good results in the knee and the technological improvements (three-dimensional tissue constructs seeded with autologous chondrocytes) this method is being increasingly applied for cartilage lesions of the talus. In contrast to the mosaicplasty donor site morbidity is low and the size of the defect is not a limiting factor. The current studies about ACT of the talus show a stable repair of the defect with mostly hyaline-like cartilage and high patient satisfaction. Therefore, the procedure can be recommended for lesions >1 cm2. Concomitant treatment of posttraumatic deformities (malalignment), ligamentous instabilities, and especially the reconstruction of bony defects are compulsory.  相似文献   
80.
Prostate cancer is one of the principal medical problems facing the male population in developed countries with an increasing need for sophisticated imaging techniques and risk-adapted treatment options. This article presents an overview of the current imaging procedures in the diagnosis of locally advanced prostate cancer. Apart from conventional gray-scale transrectal ultrasound (TRUS) as the most frequently used primary imaging modality we describe computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). CT and MRI not only allow assessment of prostate anatomy but also a specific evaluation of the pelvic region. Color-coded and contrast-enhanced ultrasound, real-time elastography, dynamic contrast enhancement in MR imaging, diffusion imaging, and MR spectroscopy may lead to a clinically relevant improvement in the diagnosis of prostate cancer. While bone scintigraphy with (99m)Tc-bisphosphonates is still the method of choice in the evaluation of bone metastasis, whole-body MRI and PET using (18)F-NaF, (18)F-FDG, (11)C-choline, (11)C-acetate, and (18)F-choline as tracers achieve higher sensitivities.  相似文献   
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