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OBJECTIVES: The clinical success of orthodontic miniplates depends on the stability of the miniscrews used for fixation. For good stability, it is essential that the application site provides enough bone of good quality. This study was performed to analyze the amount of bone available for orthodontic miniplates in the zygomatic process of the maxilla. METHODS: We examined 51 dental CT scans (Somatom Plus 4; Siemens, Erlangen, Germany) obtained from 51 fully dentate adult patients (mean age 24.0 ± 8.1 years; 27 male and 24 female) prior to third molar surgery. The amount of bone in the zygomatic process region at the level of the first molar root tips and at several other cranial levels as far as 15 mm from the root tips was measured RESULTS: Bone thickness at the root tip level averaged 4.1 ± 1.0 mm; the lowest value measured at this level in any of the patients was 2.7 mm. Bone thickness averaged 8.3 ± 1.0 mm at 15 mm cranial to the root tips; 6.9 mm was the lowest value. CONCLUSION: The zygomatic process appears to provide sufficient bone to accommodate screws for miniplate fixation. While some patients may possess a borderline amount of bone at more caudal levels, lack of volume is not a problem near the zygomatic bone.

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OBJECTIVES: The maxillary bone below the frontal process is used for orthodontic anchorage; indications have included skeletally anchored protraction of the maxilla for treating Class III malocclusions or the intrusion of teeth in patients with a deep bite. This study was conducted to assess the condition of bone before cortically implanting miniplates in that area of the maxilla. PATIENTS AND METHODS: A total of 51 thin-sliced computed tomography scans of 51 fully-dentate adult patients (mean age 24.0 ± 8.1 years; 27 men and 24 women) obtained prior to third-molar osteotomy were evaluated. Study parameters included total bone thickness, thickness of the facial cortical plate, and width of the nasal maxillary buttress. All these parameters were measured at different vertical levels. RESULTS: The bone volume adjacent to the piriform aperture was most pronounced at the basal level and decreased progressively toward more cranial levels. The basal bone structure had a mean total thickness of 7.8 mm, facial cortical plate thickness of 1.9 mm, and nasal maxillary buttress width of 9.2 mm. At 16 mm cranial to the aperture base, these values fell to 5.6 mm, 1.3 mm, and 5.8 mm, respectively. CONCLUSION: These bone measurements suggest that screws 7 mm in length can be inserted at the base level of the piriform aperture and screws 5 mm long at the cranial end of the bone.

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Severe fungal infections remain a significant cause of morbidity and mortality in neutropenic patients undergoing dose-intensive chemotherapy for malignant diseases. Chronic disseminated candidiasis (CDC) is a life-threatening complication in neutropenic patients because of the lack of responsive hematopoietic precursor cells. Resolution of Candida organ lesions after hematopoietic reconstitution may take months. Here, we report the case of a 19-year-old neutropenic woman with relapsed acute myelogenous leukemia and candidiasis of liver, spleen, and kidneys. Antifungal treatment was initiated using fluconazole and caspofungin but was changed to itraconazole and caspofungin. Despite elevated C-reactive protein (CRP) levels and detectable Candida organ lesions, antileukemic therapy was restarted with interleukin 2 at the same time as antimicrobial treatment. Eight weeks after the start of interleukin therapy, CRP levels and organ lesions were decreased significantly irrespective of continuing neutropenia. This case report describes the successful treatment of CDC during neutropenia using combination antifungal therapy and suggests controlled studies to establish optimal therapeutic strategies.

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INTRODUCTION: A two-step procedure is suggested to reduce the overall operative risk in patients with colorectal cancer and large synchronous liver metastases, which demand an extended right hemihepatectomy for R0 resection. METHODS: The clinical course and volumetric evaluation of the liver is described in three patients in whom preliminary ligation of the right branch of the portal vein was performed at the time of colon resection. RESULTS: The size of the left lateral lobes increased by 9.9%, 13.7%, and 4.9% of total liver volume, respectively. At the same time, the noninfiltrated part of the right lobes shrunk by 36.7%, 36%, and 6% ukereas metastatic growth was 26.8%, 22.3%, and 12%. After 7 weeks, extended right hemihepatectomy could be performed in all three patients without signs of hepatic insufficiency, yielding R0 resection. CONCLUSION: Can reduce the risk for extended right hemihepatectomy in selected patients with synchronous colorectal liver metastases.

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The purpose of this study is to compare triphasic helical CT and fast MRI with respect to detection, characterization and staging of suspected renal masses. To achieve this triphasic helical CT (plain, corticonephrographic and tubulonephrographic phase) and MRI with fast T(1) weighted and T(2) weighted sequences were performed in 29 patients with a suspected renal lesion. Image quality, lesion characterization and lesion extent were assessed for both methods in all patients. The acquisition phase for CT and the image sequence for MRI offering the best image quality and best diagnostic information regarding renal parenchyma, renal vessels, detection of enlarged lymph nodes, and other abdominal organs were determined. Histologically confirmed renal cell carcinomas (n=18) were staged based on the Robson classification. Quantitative data were obtained from operator-defined regions of interest (ROIs) in all acquisition phases (CT) and all image sequences (MRI). For most criteria the rating of image quality for helical CT was generally higher as compared with fast MRI. CT and MRI detected all 24 histologically proven masses, while no false positive solid tumour was diagnosed with both imaging modalities. All three acquisition phases in CT and all applied image sequences in MRI were regarded as necessary in order to gain important diagnostic information. Altogether, 12 of 18 renal cell carcinomas (67%) were correctly staged by CT and MRI. Helical CT and fast MRI allow the correct detection and characterization of suspicious renal lesions. Both imaging modalities can be recommended for clinical routine application. Although the correct histological staging of renal cancer remains difficult for both imaging methods, both are excellent in providing the critical staging information needed before surgery. Helical CT offers a significantly shorter acquisition time to cover the entire abdomen.

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Dislocated radial head fractures of the type Mason II are usually treated with screws and buttress plates. The implants are generally removed at a later date. Biodegradable implants can be applied successfully for the reduction of small radial head fractures subject to shearing forces and slight loads. The implants are completely absorbed once the fracture has healed, making a second operation for the removal of the implant unnecessary. The Polypin C-Pin is made of poly(L, DL-lactide) mixed with 10% beta-tricalcium phosphate to ensure controlled, slow degradation with no significant side effects. This new Polypin C fixation pin was clinically tested on 35 patients with radial head fractures (CCF 21B2.1 and 21B2.2) from 31.10.1996 until 1.4.2002. A total of 34 of the patients (97.1%) underwent a clinical and conventional radiological follow-up examination after an average of 38.2 months. In 29 cases a CT was also carried out. Between 18 and 24 months, two cases of grade 1 osteolysis were observed around the pin head. No trace of osteolysis was observed at the final examination in either case. According to the Broberg score, an average of 96 out of a possible 100 points were attained at the final examination (31 excellent, 2 good, 1 unsatisfactory). After a period of 24 months, the pins were no longer visible on a conventional x-ray. A CT evaluation showed a density similar to that of spongioid bone in the original pin cavities after 3 years. These excellent clinical results prove that the Polypin C is a good method to treat dislocated radial head fractures.

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BACKGROUND: Resection as the only potential cure for colorectal liver metastasis is limited by the size and the intrahepatic localization of lesions. Radiofrequency ablation (RFA) may extend the limitations of surgery. PATIENTS AND METHODS: 23 consecutive patients suffering from a total of 128 colorectal liver metastases were treated by resection and intraoperative RFA. All of these patients were irresectable by standard surgery due to volume and distribution of the lesions. 17 patients were treated by chemotherapy before RFA, with only 1 patient showing partial regression of liver metastases. In 12 lesions a new 3D navigation tool was used, that allows a virtual overlay of the RFA probe in real-time. RESULTS: 60 metastases were resected, 68 metastases were treated by RFA. There was no mortality, and complications occurred in 4 patients only (1??temporary encephalopathy, 3x cholangitis). Local tumor control according to CT scan was achieved by RFA in 93% of lesions up to 30 mm diameter (n = 45) and in 44% of lesions larger than 30 mm (n = 23). All ablations using the navigation tool were successful. After a mean follow-up of 8 +/- 5 months 12 patients are free of disease, 8 patients have either recurrent or new metastases, and 3 patients died of progressive disease. The estimated median survival time is 18 months (95% confidence interval 13-22 months). CONCLUSIONS: Intraoperative RFA of colorectal liver metastases in combination with hepatic resection is safe. Up to a lesion size of 30 mm a reliable treatment with RFA is possible. The navigation aid increases the reproducibility of the procedure.

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The report describes a rare case of an iatrogenic arteriovenous fistula of the vertebral artery to the vertebral vein which arose after insertion of a central venous catheter via the jugular vein. We give special attention to the role of colour duplex sonography in the primary diagnosis of such fistulas. As can be seen from published reports with this non-invasive examination, the diagnosis of fistulas could not be established in all cases, where an abnormal communication between the vessels was later revealed by angiography. The most probable reason is the particular feature of the anatomical course of the vertebral artery which in its middle third is protected in a bony canal through the foramina transversaria of the cervical vertebrae and can be only partially visualised by sonography. Consequently only fistulas in the visible parts of the artery can be detected by sonography. In our case the most important criteria of duplex sonography for an arteriovenous fistula were fulfilled and the diagnosis was confirmed by angiography. This procedure with primary use of colour duplex sonography and additional clarification of uncertain findings by angiography, seems to be reasonable if the symptoms are compatible with the diagnosis of an arteriovenous fistula of the neck vessels.

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We report Neocosmospora vasinfecta infection following chemotherapy for acute nonlymphocytic leukemia. N. vasinfecta, a plant pathogen, was identified by culture and genetic sequencing. Susceptibility testing revealed in vitro resistance for common antifungals.

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Percutaneous dilational tracheotomy (PDT) and conventional tracheostomy are still competing methods to provide an airway for intensive care patients requiring assisted ventilation. Tracheal stenosis is a late complication for any tracheostomy and long-term intubation. However, late complications in PDT have not been extensively studied. This article is the first to report on total atresia of the subglottic larynx and cervical trachea after PDT. The dimension of the lesion is visualized by three-dimensional reconstructed CT scan. The etiology of this condition is discussed.

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BACKGROUND: Despite the availability of antibiotics deep neck space infections with anaerobic germs (Ludwig's angina) still carry the potential for significant morbidity and mortality with delayed treatment. Usually, odontogenic infections with involvement of the submandibular space are the source of deep neck space infections in adults, whereas in the pediatric population the most common cause is acute tonsillitis with involvement of the peritonsillar space. During the second half of this century intravenous drug abusers appeared as a new group of patients at risk for deep neck space infections. When peripheral veins sclerosis the addicts feel it necessary to either inject subcutaneously or use the major vessels of the neck and groin. Intravenous drug abusers injecting the major vessels of the neck risk delayed diagnosis because of dissimulation of their injection practices. Dangerous complications of deep neck space infections may be the result. CASE: We report a clinical case with delayed diagnosis and fatal outcome. CONCLUSION: Intravenous drug abuse is a rare cause for deep neck space infections but should be considered when swelling of the neck soft tissue of uncertain cause is presented. The search for the diagnose should not keep from taking quick therapeutic steps.

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RATIONALE AND OBJECTIVES: Enhancement characteristics of a nonionic, dimeric, isotonic contrast medium (iodixanol [Visipaque]) were compared with a nonionic, monomeric contrast medium (ioversol [Optiray]) of the same iodine concentration in spiral computed tomography angiography (CTA) of the abdominal aorta. METHODS: Spiral CTA was performed in 78 patients referred for suspected renal artery stenosis (n = 35) and abdominal aortic aneurysm (n = 43). A test bolus was used to time the scan delay, and all patients were injected with 150 ml contrast medium (320 mgI/ml) of either iodixanol (n = 40) or ioversol (n = 38). Contrast enhancement was measured in the aorta, renal arteries, and renal parenchyma. RESULTS: All mean aortic enhancement was slightly higher with iodixanol than ioversol, measured at three different levels (celiac trunk 315 Hounsfield units [HU] versus 300 HU, renal arteries 325 HU versus 312 HU, aortic bifurcation 276 HU versus 266 HU). However, none of them were statistically significant (e.g., P = 0.26 at the celiac trunk level). Similar results were observed in renal artery and parenchyma enhancements. CONCLUSIONS: Iodixanol and ioversol had similar enhancement characteristics in the early arterial phase. Both substances were well tolerated and seem to be well suited for spiral CTA.

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PURPOSE: To investigate the normal sequential MR-pattern of uncomplicated fracture healing within the first 6 weeks. METHODS: In 8 patients with distal radius fracture, 4 by 4 with and without intraarticular fracture, MR examinations were performed 3-4 days after the onset of fracture and after 1, 2, 3, 4, 5 and 6 weeks using the following techniques: T1-weighted spin echo, T2-weighted spin echo, T2 proton density weighted, STIR (short inversion time inversion recovery), T2-weighted turbo spin-echo and fast field echo (FFE, gradient echo). Sequential examinations were analysed regarding 1) the appearance of fracture line, 2) development of bone marrow signal, and 3) signal changes in surrounding soft tissue. Maximum contrast of bone marrow and soft tissue was measured. RESULTS: The fracture line in bone marrow was best detectable in FFE- and T2-weighted spin ech images during the first week and in T2-weighted fast spin echo and proton density-weighted images from the 2nd to 4th week. Beginning in the 5th-6th week an increase of signal intensity in the fracture gap was typical in all sequences except for T1-weighted spin echo. The contrast maximum of bone marrow and soft tissue, best detectable in STIR- and T2-weighted spin echo images, occurred in the 1st-2nd week. CONCLUSIONS: MRI shows a typical time-depending pattern of the fracture line, surrounding bone marrow and soft tissue in normal fracture healing. The degree of injury influences the development of signal changes.

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We describe the case of a young woman with pain on turning her head attributable to a malformation of the hyoid bone. Diagnosis was established using spiral computed tomography with the patient's neck in the position of greatest discomfort and with 3-dimensional reconstruction of the hyoid bone. Prior conventional radiography and magnetic resonance imaging did not aid in finding a diagnosis. After surgical removal of both greater cornua of the hyoid bone there was a complete relief of symptoms.

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