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BACKGROUND: Lymphoma is one of the leading cancers in Saudi Arabia. Because there is a paucity of data about the prevalence of lymphomas in Saudi Arabia, numerous extensive investigations are still required. Thus, the present study aimed to assess the common patterns of lymphomas in Northwestern Saudi Arabia. METHODS: This is a retrospective study conducted at the Histopathology Departments of King Khalid and King Salman Hospitals in Hail city, Saudi Arabia, between 2008-2020. The present study comprised 134 lymphoma patients, and all data referring to these patients, such as gender, age, lymphoma type, grade, and cancer site, were retrieved. RESULTS: The most common lymphoma type was NHL, followed by HL, constituting 32.8% and 20%, respectively. There was a clear difference between male and female patients of HL type where the male was higher than the female (24% versus 15.3%). The risk of HL associated with male gender, the relative risk (RR) CI (95% Confidence interval) = 2.0077 (0.9447 - 4.2667), p = 0.0700, z statistic = 1.812. CONCLUSIONS: Lymphoma is prevalent in the Hail region with an exceptionally everincreasing incidence of HL. Wide-ranging lymphoma varieties have been explored in the Hail region, denoting large groups of unattributable etiologic modifiable risk factors.
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Linfoma , Humanos , Femenino , Masculino , Estudios Retrospectivos , Arabia Saudita , Hospitales , Factores de RiesgoRESUMEN
BACKGROUND: Patient safety and rights are the most crucial aspects of healthcare quality. In Saudi Arabia, there is a paucity of evidence concerning the perspectives of healthcare providers on the rights and safety of patients. Hence, this study aimed to assess the perceptions of healthcare providers toward patients' rights and safety in Najran, Saudi Arabia. METHODOLOGY: A cross-sectional study was undertaken in Najran, Saudi Arabia, from December 2022 to October 2023, utilizing an online survey. This study included 307 healthcare providers who responded to the questionnaire via Google web link (Google LLC, Mountain View, California, United States). RESULTS: The present research comprised 307 healthcare personnel, of whom 65.8% were male and possessed a variety of academic backgrounds. The participants exhibited a high level of support for patients' rights, as evidenced by their agreement with 88.4-90% of questions on a variety of dimensions; this demonstrated their dedication to providing patient-centered care. Concerning medical errors, a significant proportion of respondents (74.9-86.1%) exhibited comprehensive comprehension and a readiness to disclose such incidents. Diverse viewpoints surfaced regarding the attribution of errors, the necessity of reporting, and the accountability for disclosure. The interdependence of patient rights and attitudes towards patient safety was highlighted by substantial positive correlations. CONCLUSION: The viewpoints of healthcare professionals regarding medical errors and patients' liberties were discussed in this study. Advocacy for patients' rights is indicative of a commitment to patient-centered care that prioritizes autonomy and transparency. Although most participants demonstrated a willingness to report medical errors and possess a solid comprehension of their causes, divergent views emerged regarding attribution and disclosure. The interrelation between patient rights and attitudes toward patient safety was supported by positive correlations. The significance of continuous education in healthcare to promote a safety culture and enhance patient-centric practices is underscored by these results. Future research is needed to investigate the effects of culturally tailored interventions on the attitudes and practices of healthcare providers in Najran with regard to patient rights and safety.
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A substantial number of COVID-19 survivors describe ongoing symptoms long after the acute phase. This so-called post-COVID-19 syndrome or long COVID occurs irrespective of initial disease severity. Objectives: This cross-sectional study aims to describe and characterise the prevalence of persistent COVID-19 symptoms beyond three months and to evaluate the risk factors for the delayed return to the usual state of health. Methods: An electronic survey was developed, piloted, and conducted during the first wave of the COVID-19 pandemic. The survey consisted of questions exploring socio-demographic data, comorbidities, COVID-19 disease (diagnosis, presenting symptoms, management, and persistent symptoms), and the return to the usual state of health. Participants were users of social media platforms. We received results from 746 respondents. One hundred thirty-six responses were excluded due to a self-diagnosis of COVID-19. Respondents reporting a COVID-19 diagnosis 3 months or more prior to the study (N = 213) were included in the analysis. Predictors of the delayed return to the usual state of health were identified by logistic regression. Results: Three months or more after a COVID-19 diagnosis, almost half of the respondents, 109 (51.2%), had residual symptoms. The five most prevalent persistent symptoms were fatigue (13.6%), altered sense of smell (12.7%), muscle aches (10.3%), headache (9.9%), and body aches (8.5%). When questioned regarding the return to baseline health, 152 (71.4%) answered in the affirmative. The total number of chronic medical conditions was determined as a statistically significant predictor for the delayed return to the usual state of health. Conclusion: Three months or more after acute COVID-19 infection, 5 out of 10 survivors experienced persistent symptoms, and 3 out of 10 reported a delayed return to baseline health. Considering the overall burden of COVID-19 disease, this can pose health and socio-economic challenges. Therefore, health systems need support in managing long COVID and improving long-term COVID-19 outcomes.
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AIMS: This study measured the effects of 5-Fluorouracil (5-FU), calcitriol (VD3), and/or thymoquinone (TQ) single/dual/triple therapies on cell cycle progression, apoptosis, inhibition of the PI3K/AKT/mTOR pathway, and oxidative stress against colorectal cancer (CRC). MAIN METHODS: The HT29, SW480 and SW620 cell lines were treated with 5-FU (50 µM), VD3 (25 µM), and TQ (75 µM), alone or combined for 12 h, prior to cell cycle/apoptosis analyses. KEY FINDINGS: TQ monotherapy had greater anticancer effects to active VD3 or 5-FU, revealing higher expression of p21/p27/PTEN/BAX/Cyto-C/Casp-3 and increased levels of total glutathione, with inhibitions in CCND1/CCND3/BCL-2 and PI3K/AKT/mTOR molecules, alongside higher rates of apoptosis in HT29, SW480 and SW620 cells (P < 0.005 for all markers). Additionally, all combination protocols revealed enhanced modulations of the PI3K/PTEN/Akt/mTOR pathway, higher expression of p21/p27/PTEN/BAX/Cyto-C/Casp-3, and better anti-oxidant effects, than the monotherapies. Although TQ/5-FU and TQ/VD3 co-therapies were better relative to the VD3/5-FU regimen, the best tumoricidal effects were observed with triple therapy in the HT29 and SW480 cell lines, possibly by boosted attenuations of the PI3K/AKT/mTOR oncogenic pathway. In contrast, TQ single treatment was more effective than the triple therapy regimen in metastatic SW620 cells, suggesting that this protocol would be more useful therapeutically in late-stage CRC. SIGNIFICANCE: In conclusion, this study is the first to demonstrated enhanced anti-tumorigenic effects for VD3, TQ, and 5-FU triple therapy against CRC cells and could represent the best strategy for treating early stages of malignancy, whereas TQ monotherapy could be a better approach for treating metastatic forms of the disease.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Benzoquinonas/farmacología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/genética , Benzoquinonas/administración & dosificación , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Colecalciferol/administración & dosificación , Neoplasias del Colon/patología , Fluorouracilo/administración & dosificación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glutatión/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
A recent focus of quantum spin liquid (QSL) studies is how disorder/randomness in a QSL candidate affects its true magnetic ground state. The ultimate question is whether the QSL survives disorder or the disorder leads to a "spin-liquid-like" state, such as the proposed random-singlet (RS) state. Since disorder is a standard feature of most QSL candidates, this question represents a major challenge for QSL candidates. YbMgGaO4, a triangular lattice antiferromagnet with effective spin-1/2 Yb3+ions, is an ideal system to address this question, since it shows no long-range magnetic ordering with Mg/Ga site disorder. Despite the intensive study, it remains unresolved as to whether YbMgGaO4 is a QSL or in the RS state. Here, through ultralow-temperature thermal conductivity and magnetic torque measurements, plus specific heat and DC magnetization data, we observed a residual κ0/T term and series of quantum spin state transitions in the zero temperature limit for YbMgGaO4. These observations strongly suggest that a QSL state with itinerant excitations and quantum spin fluctuations survives disorder in YbMgGaO4.
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Background Head and neck lesions, which are predominantly benign, were widely reported. Some of these tumors are potentially neoplastic and others are non-neoplastic. Therefore, this study aimed to assess the clinicopathological features of patients nominated for head and neck biopsies. Methodology In this study, data regarding head and neck biopsies were retrieved from the Department of Pathology at King Khalid Hospital, Hai'l, Northern Saudi Arabia. Data referring to head and neck biopsies of patients who were diagnosed during the period from January 2018 to December 2018 were included. Results The initial clinical presentations were stated for 50/64 (78.1%) head and neck lesions, 12/64 (18.8%) head and neck cysts, 1/64 (1.6%) keloid, and 1/64 (1.6%) ischemia. With regard to the biopsy's site, most were taken from the nose followed by oral cavity, scalp, ear, face, and eye, constituting 19/64 (29.7%), 15/64 (23.4%), 9/64 (14.1%), 5/65 (7.8%), 4/64 (6.2%), and 3/64 (4.7%), respectively. Conclusion Head and neck benign lesions, predominantly inflammatory lesions, are common in Northern Saudi Arabia. Accurate identification of these lesions is important during histopathological diagnosis, as some have pathological features that mimic some potentially neoplastic lesions.
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BACKGROUND: Cancer burden can be reduced by early detection of early neoplastic changes applying suitable screening methods. This study aimed to assess the utility of nucleolar organizer regions (NORs) quantitation in early prediction of lung neoplastic transformation. METHODOLOGY: This study investigated 200 apparently healthy individuals categorized into two groups; smoking exposed individuals (N=100), and were categorized as cases, and smoking nonexposed (N=100), and were ascertained as controls. Sputum specimen was attained from each participant (paying all indispensable safety precautions and sample adequacy processes). Results: Out of the 200 volunteers assessed in the present study, mean NORs counts of >2.00 were identified in 16/200(8%) of the study subjects. All 16/16(100%) cases were found with lung epithelial metaplasia (squamous metaplasia). Out of the 100 cases, mean NORs counts of >2.00 were identified in 16/100(16%), hence, all the controls were identified with mean NORs counts of <2.00. The risk of lung cellular proliferative changes associated with smoking exposure are odds ratio (OR) (95% confidence interval, CI) = 39.2485 (2.3199-664.0052), p = 0.0110, z statistic = 2.543. CONCLUSION: NORs count is a simple, specific, cost-effective, and reliable method that can give a quantitative measurement for the risk of lung neoplastic transformation. For at risk-population (tobacco users), it is recommended to perform the argyrophilic NORs (AgNORs) method beside sputum cytology.
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Aim: Smokeless tobacco (ST) use is a significant health risk and cause of disease. Most studies conducted in the Kingdom of Saudi Arabia (KSA) focused on cigarette smoking. Therefore, the objective was to study the epidemiologic pattern and types of oral ST usage in northern and western Saudi Arabia. Materials and methods: A total of 428 volunteers living in three cities (Hail, Mecca, and Tabuk) were investigated. All of the study subjects were currently ST users of one type or more, including toombak, shammah, pan masala (PM), Afdhal, Nashooq, and others. Results: Most of the study population were found to use toombak representing 127/428 (29.7%), followed by shammah, PM, Afdhal, Nashooq, Adani, Qat, Majun, and others, representing 67/428 (15.7%), 66/428 (15.4%), 44/428 (10.3%), 36/428 (8.4%), 32/428 (7.5%), 23/428 (5.4%), 22/428 (5.1%), 21/428 (4.9%), and 13/428 (3%) respectively. Conclusion: This survey showed a high prevalence of existing ST usage among foreign workers and Saudis, which can establish a prospective public health problem. Clinical significance: Smokeless tobacco cessation is a crucial element of tobacco control policy since it is the most important determinant of many diseases, including oral cancer. Keywords: Kingdom of Saudi Arabia, Oral cancer, Pan masala, Shammah, Smokeless tobacco, Toombak.
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Uso de Tabaco/epidemiología , Tabaco sin Humo/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Estudios Transversales , Escolaridad , Humanos , Masculino , Persona de Mediana Edad , Arabia Saudita/epidemiología , Adulto JovenRESUMEN
The distribution and public health significance of Cryptosporidium species and genotypes in humans and bovine differ across geographical areas. Cryptosporidium species causes a disease known as cryptosporidiosis in humans and animals. To characterize the prevalence of cryptosporidiosis in humans in southern Assam, India, stool samples (n = 1119) of diarrhea patients were collected from different hospitals and from the community during the period January 2014 to July 2016. Fecal smears were examined microscopically for Cryptosporidium species using modified acid fast staining and were screened to ascertain the presence of Cryptosporidium antigen by enzyme-linked immunosorbent assay (ELISA). The genomic DNA of positive fecal samples were analyzed by nested polymerase chain reaction (PCR), which were subsequently genotyped by PCR-restriction fragment length polymorphism (RFLP), based on small subunit (SSU) 18S rRNA. It was found that the prevalence of Cryptosporidium spp. was high during the monsoon season. The average infection rate of Cryptosporidium spp. was found to be 2.4% (27/1119) microscopically. When subjected to nested PCR using amplification of the 18S rRNA gene, Cryptosporidium was found to be 8.57% (98/1119). Based on the 18S rRNA gene, two Cryptosporidium spp., namely Cryptosporidium andersoni (6.97%: 78/1119) and Cryptosporidium parvum (1.7%: 20/1119), were identified. Cryptosporidium andersoni infections were found to be of either zoonotic or anthroponotic origin. The prevalence was statistically significant (p = 0.03, R2 = 0.042) considering age, gender, and cast.
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Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/clasificación , Cryptosporidium/aislamiento & purificación , Diarrea/epidemiología , Diarrea/parasitología , Técnicas de Diagnóstico Molecular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios Transversales , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ensayo de Inmunoadsorción Enzimática , Heces/parasitología , Femenino , Genotipo , Humanos , Incidencia , India/epidemiología , Lactante , Recién Nacido , Masculino , Microscopía , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , ARN Ribosómico 18S/genética , Estaciones del Año , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Hot Jupiters are giant Jupiter-like exoplanets that orbit their host stars 100 times more closely than Jupiter orbits the Sun. These planets presumably form in the outer part of the primordial disk from which both the central star and surrounding planets are born, then migrate inwards and yet avoid falling into their host star. It is, however, unclear whether this occurs early in the lives of hot Jupiters, when they are still embedded within protoplanetary disks, or later, once multiple planets are formed and interact. Although numerous hot Jupiters have been detected around mature Sun-like stars, their existence has not yet been firmly demonstrated for young stars, whose magnetic activity is so intense that it overshadows the radial velocity signal that close-in giant planets can induce. Here we report that the radial velocities of the young star V830 Tau exhibit a sine wave of period 4.93 days and semi-amplitude 75 metres per second, detected with a false-alarm probability of less than 0.03 per cent, after filtering out the magnetic activity plaguing the spectra. We find that this signal is unrelated to the 2.741-day rotation period of V830 Tau and we attribute it to the presence of a planet of mass 0.77 times that of Jupiter, orbiting at a distance of 0.057 astronomical units from the host star. Our result demonstrates that hot Jupiters can migrate inwards in less than two million years, probably as a result of planetdisk interactions.
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OBJECTIVE: The aim of this study was to screen patients with oral lesions for the presence of Human Papilloma Virus (HPV) types 16 and 18. METHODS: Sixty patients aged between 11-80 years with a mean age of 46 years were examined using immunohistological techniques. All samples were retrieved from RICK during the period from August 2009 to August 2010. Out of 60 patients, 50 had Oral Squamous Cell Carcinomas (OSCCs) and the remaining ten had benign oral lesions, included as internal control. RESULTS: Of the 50 patients with OSCCs, 10 (20%) showed positive immunohistochemical results for HPV types 16 and 18 of which 50% were detected among males and 50% were demonstrated among females. The ten positive findings were Immunophenotyped as follows: five were positive with HPV type 16, four with type 18 and one was positive for HPV types 16 and18. All patients with benign oral lesions were negative for HPV immunohistochemistry. CONCLUSION: The study suggests the role of HPV 16 and 18 in the etiology of oral cancers in different parts of Sudan. However, the use of molecular techniques such as PCR are needed to confirm the results of immunohistochemistry in the role of the HPV in developing of OSCC in Sudan.
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OBJECTIVES: Degenerative changes caused by delays in urine preservation contribute to false-negative and false-positive interpretation of urothelial disease in cytology. The aim of this study is to assess whether the delay of fixation of urine samples makes any significant difference to urine cytology and morphology, and the limit of acceptability of delay for routine use in the hospital laboratory. METHODS: Three cell collection fluids were evaluated by analyzing the preservation and degeneration of cells in urine samples. In this study, 50 voided urine specimens were taken at random from females complaining of vaginal discharge. Each specimen was divided into three sterile containers. The first was immediately centrifugated and the deposit was smeared onto a cleaned micro slide and immediately fixed into 95% ethyl alcohol for 15 minutes. The remaining two were prepared in the same manner, however, the second after two hours of collection and the third after four hours of collection. The degree of degeneration and thus the preservation were assessed by a table of chosen criteria, then ranked and analyzed using Friedman's nonparametric test, at p=0.05. RESULTS: The results showed a significant difference between the preservation and the delay in urine fixation, p<0.0001. CONCLUSION: Any delay in fixation of urine specimen for cytology affects the preservation of cells, which may result in miss diagnosis. It is recommended that urine samples for cytology should be fixed immediately after collection.
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BACKGROUND: Death from cancer is high in Sudan, with low survival rates, as most of the patients present with advanced disease. Most patients receive high and repeated doses of radiotherapy or chemotherapy. The aim of this study was to investigate the feasibility of using cytological evaluation to detect oral epithelial atypia amongst these patients. As a part of the continuous development in cancer therapy, this case control study was conducted in Khartoum, Sudan. METHODS: Papanicolaou stained oral mucosal cells were obtained from 100 cancer patients receiving radiotherapy and/or chemotherapy (ascertained as cases), 50 cancer patients not exposed to either therapy (control 1), and 50 apparently healthy individuals (control 2). STATISTICAL ANALYSIS: The data was analyzed by using a computer SPSS program, to obtain the Chi-square test. RESULTS: Without prior knowledge of the subjects' group, oral epithelial atypia was detected in 7% of the cases. Inconclusive features of cytological atypia were observed in 13% of the cases. Atypia was not observed in both the control groups. Inflammatory infiltrate and viral cytopathic effects were identified in 32% and 8% of the cases respectively. CONCLUSION: Cytological atypia, viral infections, and inflammatory infiltrates were detected after exposure to radiotherapy and/or chemotherapy.
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BACKGROUND: Oral cancer (OC) mortality is very high in Sudan, particularly among men due to the habit of Toombak use (tobacco specific nitrose amine (TSN)) rich tobacco. AIMS: Our aim was to determine whether OC is gender-specific due to increased Toombak use among males as suggested a risk for subsequent development of oral cancer. SETTINGS AND DESIGN: We conducted a descriptive study of OC in Khartoum and obtained information on Toombak use, confounding variables for 39 incident patients with oral cancerous lesions and 43 hospital-based cases without apparent oral lesions. MATERIALS AND METHODS: OC was affirmed by histopathology for all patients with oral lesions, hence oral epithelial atypia and leukoplakias were detected using cytology. STATISTICAL ANALYSIS: Data analyzed using a computer SPSS program. RESULTS AND CONCLUSIONS: Of the 82 subjects, there were 57 (70%) Toombak users and 25 (30%) non-tobacco users. Among the 39 patients with OC, 24 (61.5%) were Toombak users and 15 (38.5%) were non-tobacco users. Among 43 with atypical changes, 10 (23.3%) were non-tobacco users and 33 (76.7%) were Toombak users. Regarding gender, only 11 (13.4%) were females, of whom 8 (72.7%) were non-tobacco users. We conclude that oral cancer, atypia and leukoplakia were high among males who were Toombak users. In view of the high incidence (29%) of OC due to Toombak use, we propose the implementation of oral screening programme restricted to Toombak users.
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Neoplasias de la Boca/epidemiología , Neoplasias de la Boca/etiología , Tabaco sin Humo/toxicidad , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Sudán/epidemiologíaRESUMEN
The absorption of N(2)O and CO at room temperature on finely divided ZnO surfaces gives reversible absorption bands from surface N(2)O species in the 2237-2245, 2265-2285 and 1245-1255 cm(-1) regions. The growth of the first band is at the expense of the second while its intensity and position depends on the extent of the surface carbonate, formed by the oxidation of CO by N(2)O. The order of introduction of CO and N(2)O, and whether the ZnO surface is oxidised or reduced, gave significantly different results in terms of carbonate formation. The strongest carbonate formation and implied decomposition of N(2)O, occurs at room temperature when CO is added to preadsorbed N(2)O on an oxidised ZnO surface. A single bidentate carbonate is formed under these conditions but on heating in the gas mixture to 200 degrees C an additional, possibly monodentate, carbonate occurs together with a surface formate species.
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Monóxido de Carbono/química , Óxido Nitroso/química , Espectrofotometría Infrarroja/métodos , Óxido de Zinc/química , Adsorción , Carbono/química , Química/métodos , Modelos Químicos , Oxidación-Reducción , Oxígeno/química , Temperatura , Zinc/químicaRESUMEN
In patients who show their lower teeth during smiling and facial animation, paralysis of the marginal mandibular nerve (MMN) causes a noticeable asymmetry of the lower lip due to the absence of depressor function. This paper presents a balancing technique for this lower lip asymmetry that involves resection of the depressor labii inferioris (DLI) on the nonparalysed side. The anatomy of the muscle, the operative technique, and the effectiveness of the procedure are outlined. A retrospective chart review was performed for 42 adult patients who were treated for MMN palsy with a DLI resection. Seven cases had only the MMN involved, and 35 cases had unilateral facial nerve paralysis. Thirty-six of these patients were available for a follow-up telephone survey. Of the 42 primary DLI resections performed, 36 cases had successful outcomes. Of the six patients who failed to achieve the expected results, five patients had repeat DLI resection and three of these achieved the desired result; the other two patients required a third resection. One patient continued to have DLI action with smiling and subsequently had a Botox injection into the DLI with good results. Of the 36 survey respondents, 21 patients felt their lower lip was asymmetrical at rest prior to DLI resection and 18 of these patients were improved by the procedure (P = 0.0001). Twenty-nine of the 36 patients reported that their lower lip was more symmetrical when they smiled following the DLI resection (P < 0.0001). The bilateral lack of movement in the lower lip when expressing emotions, such as anger and sorrow, was not as important to the patient as the lack of symmetry when expressing these emotions. Patients' speech either improved or showed no change, the amount patients bit their lower lip significantly improved (P = 007) whereas oral continence showed no significant changes (P = 0.147) following the DLI resection. DLI resection is a simple and effective procedure for the treatment of MMN palsy. The results are permanent and predictable. Lower lip symmetry is produced both at rest and with facial animation, without causing a functional deficit. The expected results of surgery can be trialed by local anaesthetic or botulinum toxin to block the activity of the DLI.
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Técnicas Cosméticas , Músculos Faciales/cirugía , Parálisis Facial/cirugía , Nervio Mandibular , Adulto , Anciano , Músculos Faciales/patología , Parálisis Facial/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
An angle-measuring technique based on an optical interferometer is reported. The technique exploits a Michelson interferometric configuration in which a right-angle prism and a glass strip are introduced into a probe beam. Simultaneous rotation of both components along an axis results in an optical path difference between the reference and the probe beams. In a second arrangement two right-angle prisms and glass strips are introduced into two beams of a Michelson interferometer. The prisms and the strips are rotated simultaneously to introduce an optical path difference between the two beams. In our arrangement, optimization of various parameters makes the net optical path difference between the two beams approximately linear for a rotation as great as +/-20 degrees . Results are simulated that show an improvement of 2-3 orders of magnitude in error and nonlinearity compared with a previously reported technique.