Reconstructive and Aesthetic Surgeries on the Female Genitalia. Guideline of the DGGG, DGPRÄC, OEGGG and SGGG (S2k-Level, AWMF Registry No. 009/019, May 2022).

Aim This official guideline was coordinated and published by the German Society for Gynaecology and Obstetrics (DGGG), the German Society for Plastic, Reconstructive and Aesthetic Surgery (DGPRÄC), the Austrian Society for Gynaecology and Obstetrics (OEGGG), and the Swiss Society for Gynaecology and Obstetrics (SGGG). The guideline aims to provide a consensus-based overview of reconstructive and aesthetic surgeries on female genitalia based on an evaluation of the relevant literature. Methods This S2k-guideline was developed by representative members from different medical professions on behalf of the guidelines commission of the DGGG, DGPRÄC, OEGGG and SGGG using a structured consensus process. Recommendations Statements and recommendations on the epidemiology, aetiology, classification, symptoms, diagnosis, and treatment of acquired changes of the external genitalia are presented and special situations are discussed.

Factors associated with an increased risk of SARS-CoV-2 infection in healthcare workers in aerosol-generating disciplines.

BACKGROUND: Healthcare workers (HCWs) are at a high risk of SARS-CoV-2 infection due to exposure to potentially infectious material, especially during aerosol-generating procedures (AGP). We aimed to investigate risk factors for SARS-CoV-2 infection among HCWs in medical disciplines with AGP. METHODS: A nationwide questionnaire-based study in private practices and hospital settings was conducted between 12/16/2020 and 01/24/2021. Data on SARS-CoV-2 infections among HCWs and potential risk factors of infection were investigated. RESULTS: 2070 healthcare facilities with 25113 employees were included in the study. The overall infection rate among HCWs was 4.7%. Multivariate analysis showed that regions with higher incidence rates had a significantly increased risk of infection. Furthermore, hospital setting and HCWs in gastrointestinal endoscopy (GIE) had more than double the risk of infection (OR 2.63; 95% CI 2.50-2.82, p<0.01 and OR 2.35; 95% CI 2.25-2.50, p<0.01). For medical facilities who treated confirmed SARS-CoV-2 cases, there was a tendency towards higher risk of infection (OR 1.39; 95% CI 1.11-1.63, p=0.068). CONCLUSION: Both factors within and outside medical facilities appear to be associated with an increased risk of infection among HCWs. Therefore, GIE and healthcare delivery setting were related to increased infection rates. Regions with higher SARS-CoV-2 incidence rates were also significantly associated with increased risk of infection.

SARS-CoV-2 Vaccination Rate and SARS-CoV-2 Infection of Health Care Workers in Aerosol-Generating Medical Disciplines.

Healthcare workers (HCW) who perform aerosol-generating procedures (AGP) are at high risk of SARS-CoV-2 infection. Data on infection rates and vaccination are limited. A nationwide, cross-sectional study focusing on AGP-related specialties was conducted between 3 May 2021 and 14 June 2021. Vaccination rates among HCW, perception of infection risk, and infection rates were analyzed, focusing on the comparison of gastrointestinal endoscopy (GIE) and other AGP-related specialties (NON-GIE), from the beginning of the pandemic until the time point of the study. Infections rates among HCW developed similarly to the general population during the course of the pandemic, however, with significantly higher infections rates among the GIE specialty. The perceived risk of infection was distributed similarly among HCW in GIE and NON-GIE (91.7%, CI: 88.6−94.4 vs. 85.8%, CI: 82.4−89.0; p < 0.01) with strongest perceived threats posed by AGPs (90.8%) and close patient contact (70.1%). The very high vaccination rate (100−80%) among physicians was reported at 83.5%, being significantly more frequently reported than among nurses (56.4%, p < 0.01). GIE had more often stated very high vaccination rate compared with NON-GIE (76.1% vs. 65.3%, p < 0.01). A significantly higher rate of GIE was reported to have fewer concerns regarding infection risk after vaccination than NON-GIE (92.0% vs. 80.3%, p < 0.01).

Oncoplastic breast consortium recommendations for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy.

AIM: Demand for nipple- and skin- sparing mastectomy (NSM/SSM) with immediate breast reconstruction (BR) has increased at the same time as indications for post-mastectomy radiation therapy (PMRT) have broadened. The aim of the Oncoplastic Breast Consortium initiative was to address relevant questions arising with this clinically challenging scenario. METHODS: A large global panel of oncologic, oncoplastic and reconstructive breast surgeons, patient advocates and radiation oncologists developed recommendations for clinical practice in an iterative process based on the principles of Delphi methodology. RESULTS: The panel agreed that surgical technique for NSM/SSM should not be formally modified when PMRT is planned with preference for autologous over implant-based BR due to lower risk of long-term complications and support for immediate and delayed-immediate reconstructive approaches. Nevertheless, it was strongly believed that PMRT is not an absolute contraindication for implant-based or other types of BR, but no specific recommendations regarding implant positioning, use of mesh or timing were made due to absence of high-quality evidence. The panel endorsed use of patient-reported outcomes in clinical practice. It was acknowledged that the shape and size of reconstructed breasts can hinder radiotherapy planning and attention to details of PMRT techniques is important in determining aesthetic outcomes after immediate BR. CONCLUSIONS: The panel endorsed the need for prospective, ideally randomised phase III studies and for surgical and radiation oncology teams to work together for determination of optimal sequencing and techniques for PMRT for each patient in the context of BR.

Full-Thickness Tumor Resection of Oral Cancer Involving the Facial Skin-Microsurgical Reconstruction of Extensive Defects after Radical Treatment of Advanced Squamous Cell Carcinoma.

Advanced tumors of the head and neck are challenging for the treatment specialist due to the need to synergize oncological and functional requirements. Free flap reconstruction has been established as the standard of care for defects following tumor resection. However, depending on the affected anatomic subsite, advanced tumors may impose specific difficulties regarding reconstruction, especially when full-thickness resection is required. This study aimed to evaluate reconstructive strategies and oncological outcomes in patients with full-thickness resection of the oral cavity. A total of 33 patients with extensive defects due to squamous cell carcinoma of the oral cavity were identified. Indications, reconstructive procedures, and clinical outcome were evaluated. Thirty-two patients (97%) presented locally advanced tumors (T3/T4). Complete tumor resection was achieved in 26 patients (78.8%). The anterolateral thigh flap was the most frequently used flap (47.1%), and the primary flap success rate was 84.8%. The cohort demonstrated a good local control rate and moderate overall and progression-free survival rates. Most patients regained full competence regarding oral alimentation and speech. Full-thickness tumor resections of the head and neck area may be necessary due to advanced tumors in critical anatomic areas. In many cases, radical surgical treatment leads to good oncological results. Free flap reconstruction has been shown to be a suitable option for extensive defects in aesthetically challenging regions.

Occurrence of cervical lymph node metastasis of maxillary squamous cell carcinoma - A monocentric study of 171 patients.

INTRODUCTION: Fewer than 5% of oral squamous cell carcinomas (SCC) are presented in the maxilla. The absence of cervical lymph node metastasis (LNM) is one of the main positive prognostic factors. This single-centre study analysed the cervical lymph node metastasis behaviour in patients with oral SCC of the upper jaw and serves as a basis for a cervical lymph node treatment suggestion. MATERIAL AND METHODS: The retrospective study includes 171 patients with isolated SCC of the maxilla. In addition to tumour resection, 83% of the patients underwent a selective neck dissection (ND). The data of cervical metastasis, TNM-status, tumour grade, tumour location as well as nicotine and alcohol behaviour were statistically analysed. RESULTS: The average rate of cervical metastasis was 44% in total. Tumour stage significantly affected risk for cervical metastasis (T1 = 6%, T2 = 41%, T3 = 60% and T4 = 60%) (p < 0.01). Development of cervical LNM was seemingly influenced by male gender. DISCUSSION: This study postulates a high rate of cervical metastasis of maxillary SCC. Risk for metastasis is mainly determined by the tumour stage. Alcohol and nicotine abuse have a negative impact on cervical LNM. CONCLUSION: Reviewing recent literature underlined by the illustrated data, we put up for discussion the treatment of SCC of the maxilla as similar to therapy protocols for SCC of the oral cavity. This would include an ipsilateral ND even in low tumour stage and in T4 staged tumours on both sides. However, prospective multicentre studies are needed to verify and recommend these therapy assumptions.

A system for context-aware intraoperative augmented reality in dental implant surgery.

PURPOSE: Large volumes of information in the OR are ignored by surgeons when the amount outpaces human mental processing abilities. We developed an augmented reality (AR) system for dental implant surgery that acts as an automatic information filter, selectively displaying only relevant information. The purpose is to reduce information overflow and offer intuitive image guidance. The system was evaluated in a pig cadaver experiment. METHODS: Information filtering is implemented via rule-based situation interpretation with description logics. The interpretation is based on intraoperative distances measurement between anatomical structures and the dental drill with optical tracking. For AR, a head-mounted display is used, which was calibrated with a novel method based on SPAAM. To adapt to surgeon specific preferences, we offer two alternative display formats: one with static and another with contact analog AR. RESULTS: The system made the surgery easier and showed ergonomical benefits, as assessed by a questionnaire. All relevant phases were recognized reliably. The new calibration showed significant improvements, while the deviation of the realized implants was <2.5 mm. CONCLUSION: The system allowed the surgeon to fully concentrate on the surgery itself. It offered greater flexibility since the surgeon received all relevant information, but was free to deviate from it. Accuracy of the realized implants remains an open issue and part of future work.

Prognostic relevance of induced and spontaneous apoptosis of disseminated tumor cells in primary breast cancer patients.

BACKGROUND: An imbalance between cell proliferation and programmed cell death can result in tumor growth. Although most systemic cytotoxic agents induce apoptosis in tumor cells, a high apoptotic rate in primary breast cancer correlates with poor prognosis. The aim of this study was to investigate the incidence and the prognostic significance of apoptotic disseminated tumor cells (DTC) in the bone marrow (BM) of breast cancer patients who either underwent primary surgery or primary systemic chemotherapy (PST). METHODS: A total of 383 primary breast cancer patients with viable DTC in the BM were included into this study. Eighty-five patients were initially treated with primary systemic chemotherapy whereas 298 patients underwent surgery first. Detection of apoptotic DTC were performed by immunocytochemistry using the M30 antibody which detects a neo-epitope expressed after caspase cleavage of cytokeratin 18 during early apoptosis. The median follow up was 44 months (range 10-88 months). RESULTS: Eighty-two of 298 (27%) primary operated patients and 41 of 85 (48%) patients treated with primary systemic systemic therapy had additional apoptotic DTC (M30 positive). In the neoadjuvant group M30-positive patients were less likely to suffer relapse than those without apoptotic DTC (7% vs. 23% of the events, p=0.049). In contrast, the detection of apoptotic DTC in patients treated by primary surgery was significantly associated with poor overall survival (5% vs. 12% of the events, p=0.008). CONCLUSIONS: Apoptotic DTC can be detected in breast cancer patients before and after systemic treatment. The presence of apoptotic DTC in patients with PST may be induced by the cytotoxic agents. Thus, both spontaneous and chemotherapy-induced apoptosis may have different prognostic significance.

Disseminated tumor cells as a monitoring tool for adjuvant therapy in patients with primary breast cancer.

The presence of disseminated tumor cells (DTC) in the bone marrow (BM) of early breast cancer patients at initial surgery as well as during follow-up predicts an unfavorable outcome. This study aimed to assess whether adjuvant systemic therapy has the ability to eradicate DTC and to determine the clinical impact of DTC-persistence. Between 12 and 24 months after an initial BM aspiration during primary surgery (BMA1) a second and third bone marrow aspiration (BMA2 and BMA3, respectively) was performed. DTC were identified by immunocytochemistry (pancytokeratin antibody A45-B/B3) and cytomorphology. A total of 190 patients who were DTC-positive at BMA1 were eligible for this retrospective analysis. DTC persisted in 35 of 190 (19 %) patients at BMA2 and in 11 of 71 (16 %) patients at BMA3. DTC-persistence at BMA3 was significantly lower in patients that received adjuvant endocrine therapy (p = 0.017). At BMA2, DTC-positive patients were at an increased risk of disease recurrence (HR: 4.17, 95 % CI: 1.51-11.50, p = 0.003) and death (HR: 5.02, 95 % CI: 1.156-21.83, p = 0.031). At BMA3, the presence of DTC was associated with shorter disease free survival (HR: 3.20, 95 % CI: 1.05-9.78, p = 0.010). In conclusion, a majority of initially DTC-positive primary breast cancer patients turned negative during adjuvant treatment. As DTC-persistence predicted an adverse outcome, serial DTC-determination can identify patients that will probably benefit from additional or a switch of adjuvant therapy.

The value of ultrasound-assisted pinned resorbable osteosynthesis for cranial vault remodelling in craniosynostosis.

Resorbable osteosynthesis is a widespread tool in craniofacial surgery, however only a limited number of studies have focused on ultrasound-assisted pinned resorbable systems in the treatment of craniosynostosis. Thirty-eight children with various types of craniosynostosis including scaphocephaly, trigonocephaly, anterior and posterior plagiocephaly were treated using the Sonic Welding resorbable osteosynthesis system. All patients were evaluated for operation time, stability of the surgical results, rate of local infections and visibility or palpability of the osteosynthesis material in the follow-up ranging from 15 to 21 month. Mean operation time was not significantly higher compared to conventional osteosynthesis material and all remodelled cranial vaults showed immediate stability. Only one patient showed signs of an inflammatory skin reaction, which recovered spontaneously. The number of palpable or visible plates, respectively, increased during the first months with a maximum at 12 months (34 (89%) plates palpable, 26 (68%) plates visible). After this time point, the number decreased continuously until the end of the follow-up period at 21 months when 3 (20%) plates were palpable, 0 (0%) plates were visible). Ultrasound-assisted pinned resorbable systems seem to be a promising tool in craniofacial surgery providing a timesaving and stable osteosynthesis. An initial swelling of the plates during the first 12 months before the complete degradation might result in a palpable and visible bulge.

Bilateral coronal and sagittal synostosis in X-linked hypophosphatemic rickets: a case report.

Craniosynostosis can be gene-linked, or caused by metabolic diseases, such as rickets, which results from a deficiency or impaired metabolism of vitamin D, magnesium, phosphorus or calcium leading to hypomineralization of the bone. X-linked dominant hypophosphatemic rickets (XLHR) is the most prevalent genetic type of hypophosphatemic rickets and is caused by germ line mutations in the PHEX-gene. In XLHR, only few case reports of craniosynostosis were described. Here, we present a clinical report of an 18 months old child with XLHR and bilateral coronal and sagittal synostosis who was treated by subtotal cranial vault remodelling with fronto-orbital advancement and right-angled Z-osteotomies. As a consequence of the child's diminished bone regeneration capacity, surgery that is performed after the age of 1 year requires more extensive craniectomy, multiple osteotomies and rigid fixation for calvarial vault remodelling to prevent extensive bone defects.

Is 1,25-dihydroxyvitamin D3 receptor expression a potential Achilles' heel of CD44+ oral squamous cell carcinoma cells?

The aim of this study was to analyse the expression of 1,25-dihydroxyvitamin D3 receptor (VDR) in oral cancers are squamous cell carcinomas (OSCC) to evaluate whether oral tissue may be a new potential target for biologically active 1,25-(OH)2D3 or its analogues. Expression of VDR was analysed in OSCC specimen (n=191) and cancer cell lines (BICR3, BICR56) by immunohistochemistry, real-time polymerase chain reaction (RT-PCR) analysis, and Western blotting. Scanned images were digitally analysed using ImageJ and the immunomembrane plug-in. VDR expression on protein level was correlated with proliferation marker Ki-67, clinical characteristics and impact on survival. VDR was co-labelled with CD44 and Ki-67 in double labeling experiments. Expression subgroups were identified by receiver operating characteristics (ROC) analysis. Low VDR expression was significantly associated with recurrence of the tumour. Multivariate analysis demonstrated low VDR expression as an independent prognostic factor (p=0.0005). Immunohistochemical double staining revealed VDR expression by CD44+ cancer cells. An inverse correlation of VDR+ expressing cancer cells with Ki-67 has been found, which was indicated by immunofluorescence double labeling. VDR specificity was confirmed by Western blot and RT-PCR analysis. For the first time, our study provides evidence that decreased VDR expression in OSCC might be associated with tumour relapse. Tumour cells of a putative CD44+ cancer stem cell compartment express VDR indicating a potential Achilles' heel for the treatment of OSCC although, our results do not allow any conclusion on the function of VDR. Adjuvant chemoprevention by using 1,25-(OH)2D3 or its analogues can be a successful tool targeting adjuvant residual tumour cells and will likely help therapeutic optimization for cancer patients in the clinic. However, this hypothesis requires further in vitro and in vivo studies.

Proximal segment positioning with high oblique sagittal split osteotomy: indications and limits of intraoperative mobile cone-beam computerized tomography.

OBJECTIVE: The purpose of this study was to evaluate the indications and limits for intraoperative proximal segment positioning control by mobile cone-beam computerized tomography (CBCT). STUDY DESIGN: For mandible osteotomy in orthognathic surgery, the high oblique sagittal split osteotomy (HSSO) is our standard procedure. In 22 patients, positioning control of the proximal segment was performed during and after surgery to check this alternative osteotomy technique. RESULTS: The mean intercondylar distance increased 0.31 mm in all patients. No significant change of the condyle positions was found in the axial and coronal planes. In the sagittal plane a significant change was found. In 1 case, revision was required because of a lateral shifting of the condyles. CONCLUSIONS: Intraoperative positioning control with CBCT is an effective and reliable method to avoid condyle malpositions. Only minor position changes occur when using HSSO in orthognathic surgery, without compromising temporomandibular joint function postoperatively.

Prognostic value of histamine H1 receptor expression in oral squamous cell carcinoma.

OBJECTIVES: Overexpression of the histamine H1 receptor (H1R) has been described in a variety of tumor models, but experience in oral squamous cell carcinomas (OSCC) is not available. Current adjuvant treatment options for OSCC can be improved by the identification of new targets of therapy. Herein, we evaluated H1R expression in a large patient cohort of OSCC. MATERIALS AND METHODS: H1R immunoexpression was evaluated in 191 cases of OSCC and two OSCC cell lines BICR56 and BICR3. Scanned images were digitally analyzed using ImageJ and the immunomembrane plug-in. The combined score of computer-assisted semiquantitative analysis was correlated with manually counted percentages of tumor cells by Kendall's tau (т) correlation coefficient. Disease-free survival times were estimated using the Kaplan-Meier method and were compared by using the log-rank test. Multivariate analyses were performed using the Cox proportional hazards model. RESULTS: H1R was rarely expressed in OSCC but significantly related with advanced tumor stages (n = 21/191, mean expression 63.5% of cancer cells in positive tumor samples, 95% confidence interval of the mean 53.5 to 73.6%, p = 0.006). Following univariate analysis, patients with H1R expression showed a significant poorer prognosis (p = 0.0004). Multivariate analysis revealed H1R expression as an independent prognostic factor (p = 0.0164). Expression of H1R in cancer cell lines was confirmed by specific staining of OSCC cell lines BICR56 and BICR3. CONCLUSION: This is the first study focusing on H1R expression showing a significant poorer DFS rate in the H1R+ patient cohort. Based on these data, H1R activation may promote carcinogenesis in OSCC. CLINICAL RELEVANCE: Investigation of H1R regulation and its antagonists shows a clear rationale for future supportive anticancer therapies in OSCCs.

Increased LDH5 expression is associated with lymph node metastasis and outcome in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) account for more than 90 % of all oral malignant lesions. Lactate dehydrogenase 5 (LDH5) has the highest efficiency among all other isoenzymes to catalyse pyruvate transformation to lactate and is significantly overexpressed in several different tumour entities. LDH5 overexpression confers an advantage on malignant cells, allows them to grow faster, and to metastasize. No data regarding LDH5 expression and OSCC outcome are available. Expression of LDH5 was analysed in OSCC specimen (n = 191) and cancer cell lines (BICR3, BICR56) by immunohistochemistry, real-time quantitative reverse transcription-PCR (RT-PCR) analysis, and western blotting. Scanned images were digitally analysed using ImageJ and the immunomembrane plug-in. LDH5 expression on protein level was correlated with clinicopathological characteristics and impact on survival. LDH5 was co-labelled with glucose transporter-1 (GLUT-1), Ki-67, and hypoxia inducible factor 1 (HIF-1α) in immunohistochemical double staining experiments. Expression subgroups were identified by receiver operating characteristics analysis. LDH5 expression was significantly associated with tumour progression, and recurrence of the tumour. Multivariate analysis demonstrated LDH5 expression as an independent prognostic factor (p < 0.0001). Immunohistochemical double staining experiments revealed LDH5 expression by cancer cells in association with glucose uptake (GLUT-1), proliferation (Ki-67), and hypoxia (HIF-1α). LDH5 specificity was confirmed by western blot and RT-PCR analysis. For the first time, this study provides evidence that LDH5 expression in OSCC might be associated with tumour formation and metastasis in a large patient cohort. Therefore, adjuvant therapies targeting glucose metabolism might be promising for therapy of OSCC.

Neurosensory alterations and function of the temporomandibular joint after high oblique sagittal split osteotomy: an alternative technique in orthognathic surgery.

The current most common technique for repositioning of the mandible, bilateral sagittal split osteotomy (BSSO), was first described by Obwegeser and Dal Pont in the early1960s, and has since been modified several times. However, there is always a risk of damaging the inferior alveolar nerve. We have studied 50 consecutive patients who had high oblique sagittal split osteotomy (HSSO) as an alternative to avoid damage to the nerve. The patients were evaluated for sensory alterations and function of the temporomandibular joint (TMJ). Healing of both wound and bone were complete and uneventful in all 50 patients. Mean (SD) sagittal movement of the mandible was 6.6 (2.9)mm and length of the osteotomy line was 11.0 (3.1)mm. No patient had either temporary or permanent alteration in sensitivity. Pinprick tests showed no significant changes between the preoperative and postoperative readings (p>0.16) or in the chronological results (p>0.23). No disorders of the TMJ developed. Mean (SD) mouth opening 6months postoperatively was 41.6 (8.6)mm. The lateral excursion increased postoperatively by 1.86mm to the left and by 0.76mm to the right. Protrusion increased by 0.66mm. HSSO is therefore a suitable alternative to BSSO as it avoids injury to the inferior alveolar nerve without compromising the TMJ. Ossification was uneventful though bony attachment was less than with the classic BSSO.

Magnetic resonance imaging in isolated sagittal synostosis.

Isolated fusion of the sagittal suture is the most prevalent form of craniosynostosis. Although the typical clinical appearance usually points the way to the right diagnosis, computed tomographic (CT) scans are still recommended as necessary tools for both the diagnosis of scaphocephaly and the preoperative planning. Because CT scans are accompanied by the biological effects of ionizing radiation, some authors have already postulated the use of magnetic resonance imaging (MRI) especially because MRI seems to be valuable for detecting intracranial anomalies compared with CT scans. Hence, we investigated the preoperative MRIs of 42 children with isolated sagittal synostosis to evaluate the frequency of brain anomalies and their therapeutic consequences.In our study, 10 patients (23.8%) showed pathologic MRI findings such as ventricular dilatation and hypoplastic corpus callosum, whereas 32 patients (76.2%) had an unremarkable MRI except a pathognomonic secondary deformation of the brain caused by the abnormally shaped skull, which was present in all patients. Seven patients showed clinically significant symptoms including papilledema or psychomotoric developmental delay; however, the clinical appearance was not predictive for pathologic MRI findings and vice versa.As the detection of brain anomalies had no influence on the surgical procedure or led to any additive therapy in our patients, we conclude that evaluation of possible pathologic brain findings does not legitimate the general use of MRI in clinically normal children with isolated sagittal synostosis.

Value of preoperative imaging in the diagnostics of isolated metopic suture synostosis: a risk-benefit analysis.

Radiographic evaluation including plain radiographies and computed tomographic (CT) scans are considered as a necessary tool for diagnosis of craniosynostosis. As recently concerns about harmful effects of ionising radiation in children have been raised, some authors have suggested the use of magnetic resonance imaging (MRI) as a helpful alternative in preoperative imaging of patients with isolated metopic synostosis. Besides confirming the diagnosis of trigonocephaly, MRI is the superior technique for the evaluation of underlying brain anomalies. However, if the benefit of preoperative imaging justifies possible side effects is still discussed controversially. Hence, this study investigated the value of preoperative imaging for the diagnosis of isolated synostosis of the metopic suture compared to a sole clinical examination. In a series of 63 cases with isolated metopic craniosynostosis operated at the Department of Oral and Maxillofacial Surgery, 48 (76.2%) patients received additional radiography or MRI investigation, while in 15 (23.8%) patients the diagnosis was based on clinical examinations only. In all patients, diagnosis was confirmed intra-operatively by a fused metopic suture. CT scans with three-dimensional reconstruction (12.5%) or plain radiographs (39.6%) did not provide any additional benefit for the diagnosis or the surgical treatment. In 23 patients (47.9%), MRI showed the typical soft-tissue alterations like triangular brain deformation in the frontal area. Besides these findings, no brain or other underlying anomalies were diagnosed which had required any additional treatment. The incidence of underlying brain abnormalities in isolated metopic synostosis seemed not to be different from that of the general population. As the characteristic clinical manifestations were sufficient for an accurate diagnosis of isolated metopic synostosis, and with respect to the biological effects of ionising radiation and risks of sedation especially in infants, preoperative imaging should be reduced to a minimum.

Image quality of two different mobile cone beam computed tomographs for maxillofacial surgery.

PURPOSE: We evaluated two mobile cone beam computed tomographs (mCBCT) comparing image quality with respect to radiation dosage. Image quality was analyzed by using different scanning modes. MATERIALS AND METHODS: The skulls of three human cadavers were scanned by use of conventional Computed Tomography (CT) as well as with two mobile cone beam computed tomographs (Siemens Arcadis Orbic 3D and Ziehm Vision Vario 3D). Six different acquisition modes with different radiation dosages were used. The axial views of all scans were evaluated by five medical doctors regarding image quality by identifying predefined anatomical structures of the skull. A five-point ranking scale was used. The inter-rater reliability was statistically depicted by Cohen's Kappa coefficient. A Wilcoxon signed rank test was used to evaluate the rater's results. For evaluating the signal-to-noise ratio (SNR) a Catphan 600 reference body with two different inlays was used. RESULTS: Comparing the mCBCTs, the image quality of the Siemens Arcadis Orbic 3D in high-dosage mode received the best score (median: 2.27). The inter-rater reliability was fair (Kappa=-0.030 to 0.328). The Wilcoxon test showed significant (p<0.05) different median rating values in 18 out of 21 imaging modes. The SNR was higher (better) in the high-dosage modes. CONCLUSION: Intra-operative 3D imaging by using mCBCT for maxillofacial surgery in low-dose mode acquisition is adequate in terms of signal-to-noise ratio and image quality. The image quality does not correlate in a linear manner with a higher radiation dosage. Surgeons using this technique should gather their own experience with the different acquisition modes.