18F-Fluorodeoxyglucose Positron-Emission Tomography (PET) Can Be Used to Assess Inflammation Non-invasively in Crohn’s Disease

Background

Differential therapy requires repeated diagnostic assessment for mapping and monitoring of disease activity in Crohn’s disease (CD).

Purpose

The purpose of this prospective study was to evaluate the accuracy of ¹⁸F-fluorodexyglucose positron-emission tomography (FDG-PET) for non-invasive assessment of disease activity in CD.

Methods

Forty-three patients with CD underwent ileocolonoscopy and hydromagnetic resonance imaging (hydro-MRI) as reference standards. In addition, FDG-PET was performed and correlated with clinical data, hydro-MRI, and endoscopy findings. Diagnostic accuracy was determined for all methods.

Results

Two-hundred and forty-one bowel segments could be analyzed by all methods. Of 80 endoscopically inflamed segments in CD, FDG-PET detected 72 and hydro-MRI 53 segments. Overall sensitivity was 90 % (FDG-PET) versus 66 % (hydro-MRI), and specificity was 92.6 % versus 99 %. In the proximal ileum, hydro-MRI revealed inflammation in eight out of 49 patients and FDG-PET, also, detected all of these inflamed segments. Seventeen stenoses could be identified in 43 CD patients. With regard to assessment as inflammatory or fibrotic stenosis, there was good concordance between colonoscopy, hydro-MRI, and FDG-PET. In one case only, the nature of the stenosis was assessed differently. In contrast with leukocyte numbers and CDAI, there was significant correlation of FDG-PET activity with C-reactive protein and CDEIS levels (P = 0.019 and P = 0.007, respectively).

Conclusion

FDG-PET is able to detect mucosal inflammation in CD with high sensitivity and specificity and to enable proper assessment of inflammatory activity in stenoses. FDG-PET is, thus, a promising non-invasive technique for clinical management of CD.     

Associations of reactive hyperemia index and intravascular ultrasound-assessed coronary plaque morphology in patients with coronary artery disease

Although reactive hyperemia index (RHI) predicts future coronary events, associations with intravascular ultrasound (IVUS)-assessed coronary plaque structure have not been reported. This study therefore investigated associations between RHI and IVUS-assessed coronary plaques. In 362 patients RHI was measured by noninvasive peripheral arterial tonometry and coronary plaque components (fibrous, fibrofatty, necrotic core, and dense calcium) were identified by IVUS in 594 vessel segments of the left anterior descending, circumflex, and/or right coronary arteries. RHI values <1.67 were considered abnormal. Analysis of variance was used to detect independent associations between RHI and plaque composition. Patients with an abnormal RHI had greater plaque burden (41% vs 39% in patients with normal RHI, p = 0.047). Compared to patients with normal RHI, plaque of patients with abnormal RHI had more necrotic core (21% vs 17%, p <0.001) and dense calcium (19% vs 15%, p <0.001) and less fibrous (49% vs 54%, p <0.001) and fibrofatty (11% vs 14%, p = 0.002) tissue. After adjustment for age, gender, cardiovascular risk factors, and drug therapy, abnormal RHI remained significantly associated with fibrous (F ratio 14.79, p <0.001), fibrofatty (F ratio 5.66, p = 0.018), necrotic core (F ratio 14.47, p <0.001), and dense calcium (F ratio 10.80, p = 0.001) volumes. In conclusion, coronary artery plaques of patients with abnormal RHI had a larger proportion of necrotic core and dense calcium. The association of an abnormal RHI with a plaque structure that is more prone to rupture may explain why these patients exhibit a greater risk of coronary events.     

Histological evaluation of healing after transalveolar maxillary sinus augmentation with bioglass and autogenous bone

Objectives: The aim was to evaluate histologically the outcome of a bioglass and autogenous bone (at 1 : 1 ratio) composite implantation for transalveolar sinus augmentation. Methods: In 31 patients, during implant installation ca. 4 months after sinus augmentation, biopsies were harvested through the transalveolar osteotomy by means of a trephine bur and non‐decalcified sections through the long axis of the cylinder were produced. After a strict selection process, taking into account the presurgical residual bone height and biopsy length, 8 and 15 biopsies representing the new tissues formed inside the sinus and the transalveolar osteotomy, respectively, qualified for analysis. The tissue fractions occupied by newly formed bone (mineralized tissue+bone marrow), soft connective tissue, residual biomaterial+empty spaces, and debris inside the sinus cavity or the transalveolar osteotomy were estimated. Results: Bone and connective tissue fraction in the newly formed tissues inside the sinus cavity averaged 23.4 ± 13.2% and 54.1 ± 23.5%, respectively. Residual biomaterial, empty spaces, and debris averaged 1.9 ± 3.5%, 10.5 ± 6.3%, and 8.4 ± 14.5%, respectively. In the transalveolar osteotomy, bone and connective tissue fraction averaged 41.6 ± 14.3% and 46.1 ± 13%, respectively, while the amount of residual biomaterial, empty spaces, and debris was 2.8 ± 5%, 4.7 ± 1.9%, and 3.2 ± 2.6%, respectively. Statistically significant differences between the sinus cavity and the transalveolar osteotomy were found only for bone and empty spaces' values (P=0.02 and 0.04, respectively). Conclusion: Sinus augmentation with a bioglass and autogenous bone composite is compatible with bone formation that, in a short distance from the floor of the sinus, shows similar density as that reported previously for other commonly used bone substitutes. New bone fraction inside the transalveolar osteotomy was almost twice as much as in the sinus cavity, while the amount of residual biomaterial was much less than that inside the sinus. To cite this article :
Stavropoulos A, Sima C, Sima A, Nyengaard J, Karring T, Sculean A. Histological evaluation of healing after transalveolar maxillary sinus augmentation with bioglass and autogenous bone.
Clin. Oral Impl. Res. 23 , 2012; 125–131.
doi: 10.1111/j.1600‐0501.2011.02161.x     

Craniofacial fibrous dysplasia (CFD) of the maxilla in an 11-year old boy: A case report

We present the case of a surgically treated 11-year old boy with a diagnosis of craniomaxillofacial fibrous dysplasia (CFD) in the maxillary sinus. When first seen in the outpatient clinic of our department he had minimal symptoms. After initial radiological diagnostics by computed tomography scans (CT-scans) the patient was treated operatively by radical excision of the tumor. The radiographs showed the typical intramedullary located and well-defined lesions, which eroded the cortical bone with the typical appearance of fibrous dysplasia. The histopathology showed the typical curved extending fibrous trabeculae in C, O and Y-shape which were embedded in a moderately cellular morphologically inconspicuous stroma, confirming the initial suspicion of fibrous dysplasia of the maxillary bone. Cone beam tomography was a valuable tool in determining the re-ossification of bone at the affected side. Local resection can be curative in limited disease.     

Incidence of maxillary sinusitis and oro-antral fistulae in bisphosphonate-related osteonecrosis of the jaw

ObjectiveBisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side-effect of bisphosphonate therapy. In the majority of cases BRONJ occurs in the mandible. As a consequence a detailed investigation of BRONJ of the maxilla and in particular of involvement of the maxillary sinus has largely so far been neglected. The aim of this study was to analyse the frequency of maxillary sinusitis and oro-antral fistulae in BRONJ of the maxilla.Subjects and methodsA retrospective multicentre analysis was carried out in three Departments of Oral and Maxillofacial Surgery focussing on patients suffering from BRONJ in the maxilla. The role of involvement of the maxillary sinus, in particular sinusitis and oro-antral fistula, was analysed.ResultsOut of a total of 170 patients suffering from BRONJ 53 cases (31.2%) with involvement of the maxilla were identified. At least one sign of maxillary sinusitis was present in 43.6% (23/53) and an oro-antral fistula in the course of the disease was detected in 35.8% (19/53) of those patients. The mean length of time of bisphosphonate intake was 36.16 ± 16.32 months. Zoledronate was most frequently associated (60.4%) with symptoms, followed by the combination of Zoledronate/Ibandronate (13.2%), and Zoledronate/Pamidronate or Pamidronate alone (both 7.5%).ConclusionMaxillary sinusitis and oro-antral fistulae are associated with a BRONJ manifestation in the upper jaw in approximately 44%. The involvement of the maxillary sinus should be given special attention and three-dimensional imaging modalities might be necessary, not only to evaluate the extent of necrosis, but also to exclude involvement of the maxillary sinus.     

The effect of current used bone substitution materials and platelet-rich plasma on periosteal cells by ectopic site implantation: An in-vivo pilot study

The aim of this study was to investigate de novo bone formation following ectopic site implantation of bone substitutes covered by periosteum, with and without the application of autologous platelet-rich plasma (PRP). Twenty-four weeks after subcutaneous implantation of various bone substitutes (bovine hydroxyapatite (bHAP), phycogenic hydroxyapatite (pHAP), and bioglass (BG)) in 35 mini-pigs, bone regeneration rates were compared microradiographically and histologically. Without PRP, bHAP showed a mean de novo bone formation of 32.41% ± 29.99, in contrast to the other substitute materials where no mineralization could be detected. In combination with PRP, in the bHAP (63.61% ± 12.98; p ± 0.03) and pHAP (34.37 ± 29.38; p = 0.015) group, significantly higher de novo bone formation was ascertained than without PRP. No ossification could be detected in the BG group. In conclusion, bHAP and pHAP bone substitutes in combination with PRP showed a significant positive effect on periosteal cells by de novo bone formation after ectopic, subcutaneous, low-vascular site implantation.     

Current trends and future perspectives of bone substitute materials – From space holders to innovative biomaterials

An autologous bone graft is still the ideal material for the repair of craniofacial defects, but its availability is limited and harvesting can be associated with complications. Bone replacement materials as an alternative have a long history of success. With increasing technological advances the spectrum of grafting materials has broadened to allografts, xenografts, and synthetic materials, providing material specific advantages. A large number of bone-graft substitutes are available including allograft bone preparations such as demineralized bone matrix and calcium-based materials. More and more replacement materials consist of one or more components: an osteoconductive matrix, which supports the ingrowth of new bone; and osteoinductive proteins, which sustain mitogenesis of undifferentiated cells; and osteogenic cells (osteoblasts or osteoblast precursors), which are capable of forming bone in the proper environment. All substitutes can either replace autologous bone or expand an existing amount of autologous bone graft.Because an understanding of the properties of each material enables individual treatment concepts this review presents an overview of the principles of bone replacement, the types of graft materials available, and considers future perspectives. Bone substitutes are undergoing a change from a simple replacement material to an individually created composite biomaterial with osteoinductive properties to enable enhanced defect bridging.     

Early release of interalveolar synechiae under general anesthesia through fiberscopic nasal intubation

This article presents a treatment strategy for early release of interalveolar synechiae, aiming to facilitate early oral feeding and prevent temporomandibular joint ankylosis.The treatment results of 2 patients with van der Woude syndrome were retrospectively studied. Both patients underwent early surgical release of interalveolar synechiae under general anesthesia through fiberscopic nasal intubation. The 2 patients were treated at the ages of 6 and 14 days, respectively. The interincisival distances increased from 5 and 6 mm preoperatively to 11 and 10 mm immediately after surgery. This was increased further to 25 and 20 mm at long-term follow-up (6 and 24 months).In conclusion, synechiae between the upper and lower jaws can be safely treated at a very early age under general anesthesia with fiberscopic nasotracheal intubation. The purpose of early intervention in these cases is to facilitate oral feeding and prevent temporomandibular joint ankylosis.