Combined bone and soft-tissue augmentation surgery in temporo-orbital contour reconstruction

Temporal hollowing due to temporal muscle atrophy after standard skull base surgery is common. Various techniques have been previously described to correct the disfiguring defect. Most often reconstruction is performed using freehand molded polymethylmethacrylate cement. This method and material are insufficient in terms of aesthetic results and implant characteristics. We herein propose reconstruction of such defects with a polyetheretherketone (PEEK)-based patient-specific implant (PSI) including soft-tissue augmentation to preserve normal facial topography. We describe a patient who presented with a large temporo-orbital hemangioma that had been repaired with polymethylmethacrylate 25 years earlier. Because of a toxic skin atrophy fistula, followed by infection and meningitis, this initial implant had to be removed. The large, disfiguring temporo-orbital defect was reconstructed with a PEEK-based PSI. The lateral orbital wall and the temporal muscle atrophy were augmented with computer-aided design and surface modeling techniques. The operative procedure to implant and adopt the reconstructed PEEK-based PSI was simple, and an excellent cosmetic outcome was achieved. The postoperative clinical course was uneventful over a 5-year follow-up period. Polyetheretherketone-based combined bony and soft contour remodeling is a feasible and effective method for cranioplasty including combined bone and soft-tissue reconstruction of temporo-orbital defects. Manual reconstruction of this cosmetically delicate area carries an exceptional risk of disfiguring results. Augmentation surgery in this anatomic location needs accurate PSIs to achieve satisfactory cosmetic results. The cosmetic outcome achieved in this case is superior compared with previously reported techniques.

Line focusing for soft x-ray laser-plasma lasing

A computational study of line-focus generation was done using a self-written ray-tracing code and compared to experimental data. Two line-focusing geometries were compared, i.e., either exploiting the sagittal astigmatism of a tilted spherical mirror or using the spherical aberration of an off-axis- illuminated spherical mirror. Line focusing by means of astigmatism or spherical aberration showed identical results as expected for the equivalence of the two frames of reference. The variation of the incidence angle on the target affects the line-focus length, which affects the amplification length such that as long as the irradiance is above the amplification threshold, it is advantageous to have a longer line focus. The amplification threshold is physically dependent on operating parameters and plasma-column conditions and in the present study addresses four possible cases.

Treatment of soft tissue recessions at titanium implants using a resorbable collagen matrix: a pilot study

OBJECTIVES: To histologically assess the effectiveness of a porcine-derived collagen matrix (CM) and a subepithelial connective tissue graft (CTG) for the coverage of single mucosal recessions at osseointegrated dental implants. MATERIALS AND METHODS: Chronic-type mucosal Miller Class I-like recessions (mean clinical defect height: 0.67 ± 0.33-1.16 ± 0.19 mm) were established at the buccal aspect of titanium implants with platform switch in six beagle dogs. The defects were randomly allocated to either (1) coronally advanced flap surgery (CAF) + CM, (2) CAF + CTG or (3) CAF alone. At 12 weeks, histomorphometrical measurements were made (e.g.) between the implant shoulder (IS) and the mucosal margin (PM) and IS and the outer contour of the adjacent soft tissue (mucosal thickness [MT]). RESULTS: All treatment procedures investigated were associated with an almost complete soft tissue coverage of the defect area (i.e. coronal positioning of PM relative to IS). Mean IS-PM and MT values tended to be increased in both CAF + CM (1.04 ± 0.74 mm/0.71 ± 0.55 mm) and CAF + CTG (0.88 ± 1.23 mm/0.62 ± 0.66 mm) groups when compared with CAF (0.16 ± 0.28 mm/0.34 ± 0.23 mm) alone. These differences, however, did not reach statistical significance. CONCLUSIONS: Within the limits of this pilot study, it was concluded that all treatment procedures investigated were effective in covering soft tissue recessions at titanium implants.

Analysis of 3D Soft Tissue Changes After 1- and 2-Jaw Orthognathic Surgery in Mandibular Prognathism Patients

Purpose Orthognathic surgery has the objective of altering facial balance to achieve esthetic results in patients who have severe disharmony of the jaws. The purpose was to quantify the soft tissue changes after orthognathic surgery, as well as to assess the differences in 3D soft tissue changes in the middle and lower third of the face between the 1- and 2-jaw surgery groups, in mandibular prognathism patients. Materials and Methods We assessed soft tissue changes of patients who have been diagnosed with mandibular prognathism and received either isolated mandibular surgery or bimaxillary surgery. The quantitative surface displacement was assessed by superimposing preoperative and postoperative volumetric images. An observer measured a surface-distance value that is shown as a contour line. Differences between the groups were determined by the Mann-Whitney U test. The Spearman correlation coefficient was used to evaluate a potential correlation between patients' surgical and cephalometric variables and soft tissue changes after orthognathic surgery in each group. Results There were significant differences in the middle third of the face between the 1- and 2-jaw surgery groups. Soft tissues in the lower third of the face changed in both surgery groups, but not significantly. The correlation patterns were more evident in the lower third of the face. Conclusion The overall soft tissue changes of the midfacial area were more evident in the 2-jaw surgery group. In 2-jaw surgery, significant changes would be expected in the midfacial area, but caution should be exercised in patients who have a wide alar base.

High-grade supraclavicular soft tissue sarcoma as secondary malignancy after successful treatment of acute myeloid leukemia: case report and literature review

It is well known that the treatment protocols for hematopoetic neoplasms carry a high risk of long-term oncogenicity. However, few reports have been published of sarcomas as secondary malignancies. An unusual case report of a soft tissue sarcoma appearing as a secondary cancer is presented, with a review of the published data. The present report involves a soft tissue sarcoma of the neck that occurred 18 years after curative treatment of acute myeloid leukemia by induction chemotherapy and bone marrow transplantation. Consecutive graft-versus-host disease affected the cervical skin. Soft tissue sarcomas appearing as secondary tumors are rare in oncology. The presented case describes the appearance of a sarcoma 18 years after curative treatment of acute myeloid leukemia. This is only the second case of this type reported in published studies.

Graph-Based Multi-Surface Segmentation of OCT Data Using Trained Hard and Soft Constraints

Optical coherence tomography (OCT) is a well-established image modality in ophthalmology and used daily in the clinic. Automatic evaluation of such datasets requires an accurate segmentation of the retinal cell layers. However, due to the naturally low signal to noise ratio and the resulting bad image quality, this task remains challenging. We propose an automatic graph-based multi-surface segmentation algorithm that internally uses soft constraints to add prior information from a learned model. This improves the accuracy of the segmentation and increase the robustness to noise. Furthermore, we show that the graph size can be greatly reduced by applying a smart segmentation scheme. This allows the segmentation to be computed in seconds instead of minutes, without deteriorating the segmentation accuracy, making it ideal for a clinical setup. An extensive evaluation on 20 OCT datasets of healthy eyes was performed and showed a mean unsigned segmentation error of 3.05 ±0.54 μm over all datasets when compared to the average observer, which is lower than the inter-observer variability. Similar performance was measured for the task of drusen segmentation, demonstrating the usefulness of using soft constraints as a tool to deal with pathologies.

Treatment of advanced soft-tissue sarcomas using a combined strategy of high-dose ifosfamide, high-dose doxorubicin and salvage therapies

Having determined in a phase I study the maximum tolerated dose of high-dose ifosfamide combined with high-dose doxorubicin, we now report the long-term results of a phase II trial in advanced soft-tissue sarcomas. Forty-six patients with locally advanced or metastatic soft-tissue sarcomas were included, with age <60 years and all except one in good performance status (0 or 1). The chemotherapy treatment consisted of ifosfamide 10 g m(-2) (continuous infusion for 5 days), doxorubicin 30 mg m(-2) day(-1) x 3 (total dose 90 mg m(-2)), mesna and granulocyte-colony stimulating factor. Cycles were repeated every 21 days. A median of 4 (1-6) cycles per patient was administered. Twenty-two patients responded to therapy, including three complete responders and 19 partial responders for an overall response rate of 48% (95% CI: 33-63%). The response rate was not different between localised and metastatic diseases or between histological types, but was higher in grade 3 tumours. Median overall survival was 19 months. Salvage therapies (surgery and/or radiotherapy) were performed in 43% of patients and found to be the most significant predictor for favourable survival (exploratory multivariate analysis). Haematological toxicity was severe, including grade > or =3 neutropenia in 59%, thrombopenia in 39% and anaemia in 27% of cycles. Three patients experienced grade 3 neurotoxicity and one patient died of septic shock. This high-dose regimen is toxic but nonetheless feasible in multicentre settings in non elderly patients with good performance status. A high response rate was obtained. Prolonged survival was mainly a function of salvage therapies.

Should 3K zoom function be used for detection of pneumothorax in cesium iodide/amorphous silicon flat-panel detector radiographs presented on 1K-matrix soft copies?

The purpose of the study was to evaluate observer performance in the detection of pneumothorax with cesium iodide and amorphous silicon flat-panel detector radiography (CsI/a-Si FDR) presented as 1K and 3K soft-copy images. Forty patients with and 40 patients without pneumothorax diagnosed on previous and subsequent digital storage phosphor radiography (SPR, gold standard) had follow-up chest radiographs with CsI/a-Si FDR. Four observers confirmed or excluded the diagnosis of pneumothorax according to a five-point scale first on the 1K soft-copy image and then with help of 3K zoom function (1K monitor). Receiver operating characteristic (ROC) analysis was performed for each modality (1K and 3K). The area under the curve (AUC) values for each observer were 0.7815, 0.7779, 0.7946 and 0.7066 with 1K-matrix soft copies and 0.8123, 0.7997, 0.8078 and 0.7522 with 3K zoom. Overall detection of pneumothorax was better with 3K zoom. Differences between the two display methods were not statistically significant in 3 of 4 observers (p-values between 0.13 and 0.44; observer 4: p = 0.02). The detection of pneumothorax with 3K zoom is better than with 1K soft copy but not at a statistically significant level. Differences between both display methods may be subtle. Still, our results indicate that 3K zoom should be employed in clinical practice.

Soft tissue profile changes following mandibular advancement and setback surgery an average of 12 years postoperatively

PURPOSE: The aim of this study was to assess long-term changes in position of soft tissue landmarks following mandibular advancement and setback surgery. MATERIALS AND METHODS: Twenty-seven patients (14 women, 13 men; mean age, 36 years) who had undergone either mandibular advancement (15 patients) or setback surgery (12 patients), were available for a long-term follow-up an average of 12 years postoperatively. In all of these cases, lateral cephalometric radiographs taken immediately before operation, at 1 week, 14 months, and 12 years postoperatively, were studied. RESULTS: During the 14 months postoperatively, soft tissue chin and mentolabial fold followed its underlying hard tissue in all patients. A continuous skeletal relapse was observable 12 years after mandibular advancement, but soft tissue chin moved more in an anterior direction. After mandibular setback, soft and hard tissue landmarks remained almost unchanged. Over the entire observation period, a thickening of soft tissue at pogonion was generally seen, and particularly a thickening of the whole chin in the setback group. All patients showed a significant lengthening and thinning of the upper lip. In all except 2 males, the patient's body weight increased markedly. CONCLUSION: In contrast to the immediate postoperative stage, soft tissue changes observed an average of 12 years after the primary operation do not directly follow the movements of the underlying skeletal structure. The soft tissue profile changes observed over such a long term seem to be influenced not only by the underlying skeletal structure but also by other factors such as weight gain and aging process.

Cervical soft tissue imaging using a mobile CBCT scanner with a flat panel detector in comparison with corresponding CT and MRI data sets

OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner.