Modified maxillomandibular advancement surgery for the treatment of obstructive sleep apnoea: a scoping review.

Modified maxillomandibular advancement (MMMA) has been proposed as an alternative to the classic maxillomandibular advancement (MMA) in East and Southeast Asian populations in which bimaxillary protrusion is a prevalent trait. The key difference between MMMA and MMA is the inclusion of anterior segmental osteotomies to reduce the protrusion of the perioral region. The aim of this scoping review was to identify the variations in MMMA and treatment outcomes. A search was conducted in the PubMed, Embase, and Cochrane electronic databases for articles published up to January 2023. Ten articles were included in this review. Three variations of MMMA have been reported in the literature. Treatment outcomes have mostly been favourable for all of these variations. Mandibular advancement of >10 mm and a greater than 50% reduction in the apnoea-hypopnoea index (AHI) have been well reported. Improvements in other outcome measures, such as enlargement of the airway dimension on computed tomography and the Epworth Sleepiness Scale score, have also been shown. Despite additional surgical procedures, complications have been uncommon and mostly minor in nature. It is necessary to be cognizant of MMMA and its variations when providing sleep surgery for East and Southeast Asian patients, tailoring this to the patient's profile and needs.

Placing the maxilla in the most aesthetic sagittal position: validation of several reference lines in relation to the forehead shape.

The ideal sagittal position of the maxilla is highly subjective in orthognathic surgical treatment planning. There is no consensus on an analysis to predict the ideal sagittal position of the maxilla. The objective of this study was to determine the preferred maxillary position in relation to the forehead shape, in the Southern Chinese population. The maxilla position of eight patients was simulated based on Steiner's analysis (SA), glabella vertical (GV), Andrews' Element II (AE2), and the Barcelona reference (BR). The simulations were then used in an electronic survey, where respondents ranked the images for each patient from to 1-4 (most to least attractive). A total of 128 responses were collected from dental professionals and laypersons. The most preferred to the least preferred simulation was as follows (mean rank scores for the male and female patients in parenthesis): BR (males 2.06; females 1.98), GV (males 2.11; females 2.21), SA (males 2.59; females 2.40), and AE2 (males 3.24; females 3.41). There was no significant difference in the results according to the sex, age group, or profession of the respondents. The Barcelona reference and glabella vertical are useful in predicting the ideal maxillary position in patients with a flat forehead, and the Barcelona reference is the most preferred in patients with a rounded forehead.

The role of anterior segmental osteotomies in orthognathic surgery for protrusive faces in a Southeast Asian population: 10-year retrospective data of 51 patients treated in a single centre.

Bimaxillary protrusion is a dentofacial deformity common in the East Asian population. It is often difficult to decide between orthodontic and surgical retraction to treat patients with bimaxillary protrusion, especially if surgery to correct skeletal base discrepancies is also required. The objective of this study was to investigate the treatment outcomes of surgical versus orthodontic retraction in patients with bimaxillary protrusion undergoing orthognathic surgery. A retrospective cohort study was conducted, where the medical records and radiographs of 51 patients with bimaxillary protrusion who had an anterior segmental osteotomy concomitant with orthognathic surgery were examined. Patients who had bimaxillary anterior segmental osteotomies were more likely to achieve an inter-incisal angle of 135 ± 5° at the end of treatment, when compared to patients who had orthodontic retraction (P < 0.01). The total treatment duration of patients who had bimaxillary anterior segmental osteotomies was significantly shorter as compared to that of the patients who only had these osteotomies in the maxilla (P < 0.001) or mandible (P = 0.012). Complications and permanent long-term sequelae following anterior segmental osteotomies were uncommon. It is concluded that bimaxillary anterior segmental osteotomies are a viable alternative for patients with concomitant bimaxillary protrusion and skeletal base discrepancies. This allows for a significantly shorter treatment time and greater correction of inter-incisal angles, without a significant increase in complications.

Simultaneous cardio-cerebral infarction: a meta-analysis.

BACKGROUND/INTRODUCTION: Cardio-cerebral infarction (CCI), which involves the simultaneous occurrence of acute ischaemic stroke and acute myocardial infarction, has a reported incidence of 0.0009%. Treatment of CCI presents a dilemma to physicians as both conditions are time critical. Despite the need for standardized treatment protocols, published data are sparse. AIM: We aimed to summarize the reported cardio-cerebral infarction cases in the literature. DESIGN: Meta-analysis. METHODS: Four databases, Pubmed, Embase, Scopus and Google Scholar were searched until 25 August 2020. A title and abstract sieve, full-text review and extraction of data were conducted independently by three authors. RESULTS: A total of 44 cases of CCI were identified from 37 case reports and series; 15 patients (34.1%) were treated using percutaneous coronary intervention (PCI) with stent, 8 patients (18.2%) were treated with a PCI without stent, 10 patients (22.7%) were treated via a cerebral vessel thrombectomy and 8 patients (18.2%) were treated via a thrombectomy of a coronary vessel. For medications, 20 patients (45.5%) were treated with thrombolytics, 10 patients (22.7%) were treated with anticoagulants, 8 patients (18.2%) were treated with antiplatelets and 11 patients (25.0%) were treated with anticoagulants and antiplatelets. Of 44 patients, 10 patients died, and 9 of those were due to cardiac causes. Among the 44 patients, days to death was observed to be a median of 2.0 days (interquartile range (IQR): 1.5, 4.0). The modified Rankin Score was measured in nine patients, with a median score of 2.0 (IQR: 1.0, 2.5) being reported. DISCUSSION/CONCLUSION: The condition of CCI has substantial morbidity and mortality, and further studies are needed to examine the optimal diagnostic and treatment strategies of these patients.

Healthcare workers acquired COVID-19 disease from patients? An investigation by phylogenomics.

The increasing number of coronavirus disease 2019 (COVID-19) cases in the community has posed a significant epidemic pressure on healthcare settings. When healthcare workers (HCWs) acquire COVID-19, contact tracing and epidemiological investigation might not be adequate for determining the source of transmission. Here, we report a phylogenetic investigation involving two infected HCWs and nine patients to determine whether patient-to-HCW transmission had occurred in a hospital without a previous COVID-19 outbreak. This is the first study to apply phylogenomics to investigate suspected nosocomial transmission in a region with low prevalence of COVID-19. Our results do not support the occurrence of direct patient-to-HCW transmission.

Changes in bite force after orthognathic surgical correction of mandibular prognathism: a systematic review.

Patients requesting treatment for mandibular prognathism seek functional and aesthetic improvements. Improvements in bite force and efficiency are generally used as measures of better function. It is unclear what effect the surgical correction of mandibular prognathism will have on the patient's occlusal forces. The literature was searched using medical subject heading (MeSH) and key word terms 'bite force', 'osteotomy', 'orthognathic surgery', and 'prognathism'. A total of 17 articles were included in this review. These included a total of 697 patients, who ranged in age from 15 to 44 years. Male patients outnumbered female patients in only one study. Five hundred and thirty-two patients underwent bilateral sagittal split osteotomy, 108 patients underwent intraoral vertical ramus osteotomy, and 24 patients underwent extraoral vertical ramus osteotomy (approach unspecified). In general, masticatory efficiency at 3 months after surgery was greater than that found pre-surgically; the increase was significant at 6 months after surgery. The occlusal contact area and points tended to increase from 3 months after surgery, and there was a significant increase at 12 months after surgery. Occlusal forces, although improved, will be lower in corrected prognathic patients than in normognathic patients even at 2 years after surgery.

Autoimmune encephalitis.

Over the past decade, the clinical spectrum of autoimmune encephalitis has expanded with the emergence of several new clinicopathological entities. In particular, autoimmune encephalitis has recently been described in association with antibodies to surface receptors and ion channels on neurological tissues. Greater clinician awareness has resulted in autoimmune encephalitis being increasingly recognised in patients with unexplained neurological and psychiatric symptoms and signs. The clinical spectrum of presentations, as well as our understanding of disease mechanisms and treatment regimens, is rapidly developing. An understanding of these conditions is important to all subspecialties of Internal Medicine, including neurology and clinical immunology, psychiatry, intensive care and rehabilitation medicine. This review provides a contemporary overview of the aetiology, investigations and treatment of the most recently described autoimmune encephalitides.

Three decades of sea water abstraction by Kapar power plant (Malaysia): What impacts on tropical zooplankton community?

Zooplankton samples collected before (1985-86) and after (2013-14) the establishment of Kapar power station (KPS) were examined to test the hypothesis that increased sea surface temperature (SST) and other water quality changes have altered the zooplankton community structure. Elevated SST and reduced pH were detected between before and after impact pairs, with the greatest impact at the station closest to KPS. Present PAHs and heavy metal concentrations are unlikely causal factors. Water parameter changes did not affect diversity but community structure of the zooplankton. Tolerant small crustaceans, salps and larvaceans likely benefited from elevated temperature, reduced pH and shift to a more significant microbial loop exacerbated by eutrophication, while large crustaceans were more vulnerable to such changes. It is predicted that any further rise in SST will remove more large-bodied crustacean zooplankton, the preferred food for fish larvae and other meroplankton, with grave consequences to fishery production.

Lymph node characterization in vivo using endoscopic ultrasound spectrum analysis with electronic array echo endoscopes.

Our purpose was to demonstrate the use of radiofrequency spectral analysis to distinguish between benign and malignant lymph nodes with data obtained using electronic array echo endoscopes, as we have done previously using mechanical echo endoscopes. In a prospective study, images were obtained from eight patients with benign-appearing lymph nodes and 11 with malignant lymph nodes, as verified by fine-needle aspiration. Midband fit, slope, intercept, correlation coefficient, and root-mean-square (RMS) deviation from a linear regression of the calibrated power spectra were determined and compared between the groups. Significant differences were observable for mean midband fit, intercept, and RMS deviation (t test P < 0.05). For benign (n = 16) vs. malignant (n = 12) lymph nodes, midband fit and RMS deviation provided classification with 89 % accuracy and area under receiver operating characteristic (ROC) curve of 0.95 based on linear discriminant analysis. We concluded that the mean spectral parameters of the backscattered signals from electronic array echo endoscopy can provide a noninvasive method to quantitatively discriminate between benign and malignant lymph nodes.

Effect of replacement of mandibular defects with a modular endoprosthesis on bone mineral density in a monkey model.

The effect of mandibular modular endoprostheses on bone mineral density (BMD) in the stem regions was studied. Modular endoprostheses were inserted into standardized mandibular condyle or body defects in 16 Macaca fascicularis. Each group of eight monkeys was divided into two groups, one killed at 3 months, the other at 6 months post-surgery. The mandibles were harvested, sectioned and scanned with a micro-computed tomography scanner. The reconstructed slices, made at a right angles to the long axis of the prosthesis, were analysed using software to calculate BMD in regions of interest buccal, lingual and inferior to the stems of the endoprosthesis. Measurements of the contralateral sides of three monkeys that underwent a similar procedure were used as control/baseline BMD. BMD for the condyle replacement group did not differ significantly from the control group. At 6 months, BMD decreased slightly; significant only at the inferior region. BMD for the body replacement group was significantly lower in all regions compared with control and condyle replacement groups probably because of connection screw loosening and infection. Loss of BMD in the peri-implant region of a modular endoprosthesis for mandibular replacement is minimal up to 6 months postoperatively, provided the device remains stable and well-fixed.

Review of biomechanical models used in studying the biomechanics of reconstructed mandibles.

This study looked at computer and physical biomodels used to study the biomechanical performance of mandibular reconstruction, reviews the literature and explains the strengths and limitations of the models. Electronic databases (Pubmed, Medline) were searched. 17 articles were selected. Computer biomodels can be divided into virtual biomodels (mainly used for clinical diagnosis and treatment planning) and computational models (e.g. finite element analysis), they can predict areas most likely to fail based on internal stress distribution and areas of maximum stress concentration. Physical biomodels include: rapid prototyping, animal bone, human cadaveric bone, and bone substitute models. Physical models allow testing on a gross level to give fatigue performance and fracture strength. The use of bone substitutes allows a more consistent specimen size and a reduction in sample size. Some commercially available products can replicate the material properties of bone. The use of any biomodel depends on the question being asked: the bending strength of a reconstruction plate would necessitate a three point bending test; the biomechanical performance of a new method of reconstruction (e.g. the mandibular modular endoprosthesis) would necessitate finite element analysis to predict areas of likely failure and also a physical biomodel to look at fatigue failure.

Biomechanics of mandibular reconstruction: a review.

Knowledge of the biomechanics of the mandible allows the surgeon to understand the forces acting on the mandible during function and the resulting deformation that can occur. This allows the appropriate selection and placement of osteosynthesis plates to neutralize these forces. Many methods have been proposed for mandibular reconstruction, each of which has strengths and weaknesses. Most papers evaluating these techniques have focused on survival rates and the quality of the grafted bones, and there have been few studies of the biomechanics (stress distribution and strength) of the various types of reconstructed mandibles. This paper reviews the biomechanics of the mandible and the various methods of reconstruction reported in past studies.

Distribution of integron-associated trimethoprim-sulfamethoxazole resistance determinants among Escherichia coli from humans and food-producing animals.

AIMS: To compare the distribution of integrons and trimethoprim-sulfamethoxazole resistance genes among Escherichia coli isolates from humans and food-producing animals. METHODS AND RESULTS: A collection of 174 multidrug-resistant E. coli isolates obtained from faecal samples of food-producing animals (n = 64) and humans (n = 59), and patients with urinary tract infections (n = 51) in Hong Kong during 2002-2004 were studied. The strains were analysed for their phylogenetic groups, the presence of sul genes (sul1 and sul2), integrons (intl1 and intl2) and class 1 integron-associated dfr cassette genes by PCR, restriction enzyme analysis and sequencing. Integrons were identified in 110 (63.2%) isolates. The prevalence of integrons was significantly different according to the specimen sources (animal faecal 84.4%, human faecal 67.8% and human urinary 31.4%) and phylogenetic groups (B1 80.8%, A 77.6%, D 54.1% and B2 11.5%). Faecal isolates (both human and animal) are more likely to belong to group A and B1. In contrast, most urinary isolates were either groups B2 and D. Among dfr containing isolates, dfrA1 and dfrA12 were almost exclusively found in strains of phylogenetic groups A and B1; and were present in animal and human faecal isolates. In contrast, dfrA17 was found in both faecal and urinary isolates and comprised strains from all phylogenetic groups. The sul1 and sul2 genes were equally prevalent among the isolates irrespective of the specimen source and phylogenetic group status. Pulsed-field gel electrophoresis analysis of isolates with identical cassette genes showed that they were genetically diverse. CONCLUSIONS: More animal faecal isolates carry class 1 integrons than human faecal and human urinary isolates, and the distribution of phylogenetic groups is common across animal and human faecal isolates but different from human urinary isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: Commensal isolates from food-producing animals are an important reservoir for integrons carrying antibiotic resistance genes.

Automatic semantic annotation of real-world web images.

As the number of web images is increasing at a rapid rate, searching them semantically presents a significant challenge. Many raw images are constantly uploaded with little meaningful direct annotations of semantic content, limiting their search and discovery. In this paper, we present a semantic annotation technique based on the use of image parametric dimensions and metadata. Using decision trees and rule induction, we develop a rule-based approach to formulate explicit annotations for images fully automatically, so that by the use of our method, semantic query such as " sunset by the sea in autumn in New York" can be answered and indexed purely by machine. Our system is evaluated quantitatively using more than 100,000 web images. Experimental results indicate that this approach is able to deliver highly competent performance, attaining good recall and precision rates of sometimes over 80%. This approach enables a new degree of semantic richness to be automatically associated with images which previously can only be performed manually.

Consensus guidelines on anti-beta 2 glycoprotein I testing and reporting.

Consensus guidelines on anti-beta 2 glycoprotein I (anti-beta2GPI) testing have been developed to help minimise laboratory variation in the performance and reporting of assays for these antibodies. These guidelines include minimum and optional recommendations for the following aspects of anti-beta2GPI testing and reporting: (1) isotype of anti-beta2GPI tested; (2) specimen type; (3) controls and assay precision; (4) calibrators; (5) patient samples; (6) rheumatoid factors and IgM anti-beta2GPI testing; (7) reporting of results; (8) cutoff values; and (9) interpretative comments. Issues related to inter-kit/assay standardisation and the manufacturing process of commercial anti-beta2GPI kits/assays have not been addressed in the current guidelines.

Alveolar haemorrhage in anti-glomerular basement membrane disease without detectable antibodies by conventional assays.

Anti-glomerular basement membrane (anti-GBM) disease represents the spectrum of disease attributable to circulating anti-GBM antibodies. While active anti-GBM disease in the absence of circulating anti-GBM antibodies has been described, it is considered rare with the use of current routinely available assays. We report four subjects with features consistent with active anti-GBM antibody disease without detectable antibodies by routinely available enzyme linked immunosorbent assay (ELISA) and immunoblot techniques. All were smokers who presented with diffuse alveolar haemorrhage, minimal renal involvement, and undetectable anti-GBM antibodies. Seronegative anti-GBM disease with predominant pulmonary involvement may be more common than previously appreciated and should be part of the differential diagnosis for otherwise unexplained diffuse alveolar haemorrhage. Renal biopsy with immunofluorescent studies should be considered in the diagnostic evaluation of such subjects, including those with idiopathic pulmonary haemosiderosis.

'Office-hour' ambulatory blood pressure monitoring is sufficient for blood pressure diagnosis.

We conducted this study to determine whether 'office hour', defined as time period from 0800 to 1800 hours, ambulatory blood pressure monitoring (ABPM) predicts daytime ('waking-hour') and 24-h ABPM results, and to examine the impact of sleep disturbance on ABPM and nocturnal dip. Eighty-four patients (mean age 49+/-18 years, 47 males) were studied. Systolic, diastolic and mean 4-, 6-, 8-, 'office-hour' as well as 'waking-hour' blood pressures (BPs) were obtained from 24-h ABPM readings. Of these, no statistical differences were found between 8-h and 'office-hour' systolic, diastolic and mean BPs compared to 'waking-hour' values. There was complete concordance between 'office-hour' and 'waking-hour' ABPM diagnosis based on British Hypertension Society definitions. Sleep disturbance was found in 22 patients (26%). Although nocturnal dip was not significantly different in either sleep-disturbed or non-disturbed patients, patients who reported sleep disturbance had significantly higher proportion of borderline/abnormal BP diagnosis compared to non-sleep-disturbed counterpart during both 'waking hour' and night time. In patients without sleep disturbance, there was complete concordance between 'office-hour', 'waking-hour' and 24-h ABPM diagnosis based on British Hypertension Society definitions. 'Office-hour' ABPM is predictive of 'waking-hour' and 24-h ambulatory BP readings. Sleep disturbance is common in patients undergoing the test, and significantly raises the BP readings. We therefore propose 'office-hour' ABPM as an accurate, reliable and comfortable method of continual non-invasive BP monitoring, and omitting routine night time BP monitoring.