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Fulltext Is the phone call the most effective method for recall in cervical cancer screening?--results from a randomised control trial

Abdul Rashid RM, Mohamed M, Hamid ZA, Dahlui M

Asian Pac J Cancer Prev, 2013;14(10):5901-4.
PMID: 24289597

OBJECTIVE: To compare the effectiveness of different methods of recall for repeat Pap smear among women who had normal smears in the previous screening.
DESIGN: Prospective randomized controlled study.
SETTING: All community clinics in Klang under the Ministry of Health Malaysia.
PARTICIPANTS: Women of Klang who attended cervical screening and had a normal Pap smear in the previous year, and were due for a repeat smear were recruited and randomly assigned to four different methods of recall for repeat smear.
INTERVENTION: The recall methods given to the women to remind them for a repeat smear were either by postal letter, registered letter, short message by phone (SMS) or phone call.
MAIN OUTCOME MEASURES: Number and percentage of women who responded to the recall within 8 weeks after they had received the recall, irrespective whether they had Pap test conducted. Also the numbers of women in each recall method that came for repeat Pap smear.
RESULTS: The rates of recall messages reaching the women when using letter, registered letter, SMS and phone calls were 79%, 87%, 66% and 68%, respectively. However, the positive responses to recall by letter, registered letter, phone messages and telephone call were 23.9%, 23.0%, 32.9% and 50.9%, respectively (p<0.05). Furthermore, more women who received recall by phone call had been screened (p<0.05) compared to those who received recall by postal letter (OR=2.38, CI=1.56-3.62).
CONCLUSION: Both the usual way of sending letters and registered letters had higher chances of reaching patients compared to using phone either for sending messages or calling. The response to the recall method and uptake of repeat smear, however, were highest via phone call, indicating the importance of direct communication.
Study site: Klinik Kesihatan, Kelang, Selangor, Malaysia
Congenital pseudoarthrosis of the tibia: healing by lengthening over a rod without compression of the nonunion. A preliminary report

Muhammad Abdul Jamil MK, Abdul Rashid AH, Ibrahim S

J Pediatr Orthop B, 2013 May;22(3):207-12.
PMID: 22182834 DOI: 10.1097/BPB.0b013e32834ecc01

This preliminary report is on two patients with congenital pseudoarthrosis of the tibia who had a persistent nonunion following intramedullary rodding and bone grafting. We do not advocate repeated surgery to achieve union. When limb length discrepancy becomes greater than 5 cm, we proceeded with an Ilizarov procedure with the primary aim of equalizing limb length rather than achieving union. Healing of the pseudoarthrosis occurred in both patients after lengthening over the intramedullary rod without compression of the nonunion site. We believe that union occurs because of hyperaemia during the lengthening. This approach minimizes the repeated surgeries that are usually needed and thus ensures a more normal childhood without frequent hospitalizations.
A rare case of diplopodia and syndactyly: anatomical and surgical considerations

Kadir KH, Abdul Rashid AH, Das S, Ibrahim S

J Foot Ankle Surg, 2011 Mar-Apr;50(2):252-6.
PMID: 21354013 DOI: 10.1053/j.jfas.2010.10.017

Diplopodia is a rare congenital disorder that has not been extensively discussed in textbooks, and case reports appear to be the main source of information. Although the exact cause of diplopodia remains unknown, the presence of extra digits as well as metatarsals and tarsals allows it to be differentiated from pedal polydactyly. Syndactyly refers to the congenital fusion of the digits. Concomitant bilateral syndactyly and diplopodia is extremely unusual, and in this report we describe a case of right diplopodia and left polydactyly combined with bilateral manual syndactyly in a 15-year-old girl who was ultimately treated with through-the-knee amputation. Radiological examination of the right leg revealed tibial hypoplasia and the right foot displayed 8 digits with corresponding metatarsals and tarsals, whereas the left leg revealed 2 extra digits on the medial aspect of the foot with corresponding metatarsal and tarsal bones. Anatomical dissection of the right foot revealed that it was divided into halves consisting of 8 toes with corresponding metatarsals and tarsals, as well as tibial hypoplasia and absence of the great toe. Diplopodia associated with tibial hypoplasia and syndactyly can be treated surgically, and the present case report details the clinical, radiological, and anatomical elements of this rare deformity.
Fulltext Incremental Role of Fluorine 18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Assessment of Computed Tomography-Inconspicuous Pancreatic Lesions

Ahmad Saad FF, Abdul Rashid AM, Md Noh MSF

J Pancreat Cancer, 2017;3(1):66-70.
PMID: 30631845 DOI: 10.1089/pancan.2017.0014

Background: Pancreatic malignancies encompass a heterogenous group of disorders, with poor prognosis at diagnosis. Traditionally, conventional computed tomography (CT) has been used for diagnosis, staging, and follow up. However, this technique lacks functional information; and is limited in diagnosis of occult pancreatic disease. Hybrid imaging in the form of positron emission tomography (PET)/CT provides a potential avenue for early detection and subsequent appropriate therapy. Case Presentation: A 60-year-old male, with a history of abdominal aortic aneurysm which was repaired, came with a complaint of 2 months history of back pain, radiating to the front. The pain was relieved on leaning forward, and aggravated by lying on his back. CT angiography of the abdomen was done, which revealed a concealed aortic aneurysm and a significant atrophy of the pancreatic tail. The serum cancer antigen (CA) 19-9 was elevated (50.0 U/mL, reference range 0.0-37.0 U/mL). At this juncture, the PET scan done revealed no discernible abnormalities. Patient was put on close follow-up in view of the rising trend of CA 19-9 levels. Three months following the initial scans, a repeat 18F-FDG (fluorine 18 fluorodeoxyglucose) PET/CT revealed an FDG-avid lesion at the neck of the pancreas on PET without perceptible changes on the correlated CT. A Whipple's procedure ensued, with histopathological examination findings of pancreatic adenocarcinoma. Conclusion: This article discusses the role of PET/CT in the early diagnosis of inconspicuous pancreatic lesions; which could have averted immediate medical therapy.
Fulltext Development and Validation of a Questionnaire on Knowledge, Attitude, and Perception Towards Allergic Reactions of Paracetamol

Dellemin NA, Zahari Z, Ahmad Hassali MA, Abdul Rashid S

J Pharm Bioallied Sci, 2020 10 08;12(4):428-435.
PMID: 33679089 DOI: 10.4103/jpbs.JPBS_247_19

Introduction: National Pharmaceutical Regulatory Agency, Ministry of Health Malaysia has received 1018 adverse drug reaction reports related to paracetamol with 1972 adverse events from the year 2000 to February 2015. Serious skin reactions including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis, and acute generalized exanthematous pustulosis may develop as a result of allergic reactions of paracetamol. This study aimed to develop and validate a questionnaire regarding Knowledge, Attitude, and Perception towards Allergic Reactions of Paracetamol (KAP-ARP) among the general population.
Materials and Methods: Content and face validity of the KAP-ARP were determined by four experts and 20 respondents, respectively. A questionnaire with 36 items, consisting of 16 Knowledge, 9 Attitude, and 11 Perception items, was distributed to 177 respondents. Exploratory factor analysis (EFA) was performed for construct validity. Cronbach's alpha was used to determine the reliability of the questionnaire.
Results: EFA constructed 13 Knowledge, 8 Attitude, and 8 Perception items. The final KAP-ARP questionnaire is reliable based on its internal consistency reliability (Knowledge: α = 0.78; Attitude: α = 0.63; Perception: α = 0.70).
Conclusion: A valid and reliable questionnaire that is useful for measuring KAP-ARP among the general population has been developed.
Fulltext Cubitus Valgus with Tardy Ulnar Nerve Palsy - Is Anterior Transposition of the Ulnar Nerve Always Necessary? A Case Report

Anuar-Ramdhan IM, Remli R, Abdul-Rashid AH, Ibrahim S

Malays Orthop J, 2020 Jul;14(2):126-129.
PMID: 32983387 DOI: 10.5704/MOJ.2007.010

Tardy ulnar nerve palsy is a known complication of cubitus valgus. The options for treating the ulnar neuropathy include anterior nerve transposition or neurolysis. We report on an 11-year-old boy who had a tardy ulnar nerve palsy due to cubitus valgus resulting from a non-union of a lateral condyle fracture of the humerus. Anterior transposition of the ulnar nerve was not done after the closing wedge osteotomy of the distal humerus. The close wedge osteotomy relieved the tension on the nerve and not transposing the ulnar nerve anteriorly prevented an iatrogenic nerve injury. The patient had no restriction with activities of daily living at the six years follow-up although neurological recovery was incomplete.
Fulltext Tuberculous Myelopathy Associated with Longitudinally Extensive Lesion: A Clinicoradiological Review of Reported Cases

Md Noh MSF, Bahari N, Abdul Rashid AM

J Clin Neurol, 2020 Jul;16(3):369-375.
PMID: 32657056 DOI: 10.3988/jcn.2020.16.3.369

Acute transverse myelitis is an inflammatory disorder of the spinal cord in which there is no evidence of spinal cord compression. Longitudinally extensive transverse myelitis (LETM) is a specific subtype of acute transverse myelitis that usually affects three or more vertebral levels and produces marked neurological deficits. While the most-common cause of LETM is neuromyelitis optica or neuromyelitis optica spectrum disorder, there are rare cases of other causes mimicking this condition, including tuberculosis (TB). We sought to review the clinicoradiological features of TB myelopathy associated with longitudinally extensive lesion, which may mimic LETM, in the English literature. We searched the PubMed, Google Scholar, Web of Science, and Scopus databases for relevant articles using search terms including "longitudinally extensive transverse myelitis," "tuberculosis," "TB spinal cord," and various combinations of these expressions. Full-text papers were selected without limiting the publication year. We also examined the reference lists of key papers to identify further articles that are potentially relevant. We found 10 cases in 7 papers describing TB myelopathy associated with longitudinally extensive lesion. The demographics, clinical features, relevant cerebrospinal fluid findings, and radiological findings were compiled and summarized. TB myelopathy associated with longitudinally extensive lesion is very rare, with no documented prevalence. Early and accurate diagnosis is important since the condition is potentially treatable.
The role of social media in primary care

Abdul Rashid A, Kamarulzaman A, Sulong S, Abdullah S

Malays Fam Physician, 2021 Jul 22;16(2):14-18.
PMID: 34386159 DOI: 10.51866/rv1048

Online activities have become the norm. From searching for new information to conducting business meetings, social media's role in daily life continues to grow in prominence. It is estimated that the majority of the population uses social media, and users include doctors and other healthcare professionals. It is critical for primary care doctors to note how social media can substantially influence one's healthcare behaviour and decision making. Because primary care doctors are usually the first line of contact for patients, they are the most easily accessible and most instrumental in using social media to steer the public toward proper information on healthcare.
Fulltext Anxiety Reaction in Children During Cast Removal using Oscillating Saw versus Cast Shear - A Randomised, Prospective Trial

Mohamed-Zain NA, Jamil K, Penafort R, Singh A, Ibrahim S, Abdul-Rashid AH

Malays Orthop J, 2021 Jul;15(2):122-128.
PMID: 34429832 DOI: 10.5704/MOJ.2107.018

Introduction: To compare the anxiety levels demonstrated by children during cast removal procedure between oscillating saw vs cast shear methods.
Material and methods: A randomised prospective study of 102 children (mean age 8.3 ± 3.5 years) with fractures involving upper or lower limbs. Children undergoing removal of cast were divided into 2 groups; either by an oscillating saw or a cast cutting shear. The level of anxiety was assessed by recording the heart rate with a portable fingertip pulse oximeter before, during and after removal of the cast. Objective assessment was performed by documenting the fear level on Children's Fear Scale (CFS).
Results: There was a significant increase in the heart rate of children during cast removal while using the oscillating saw compared to cast shear (p<0.05). The noise level produced by the saw exceeded 80 dB (mean 103.3 dB). The fear level was significantly lower in the cast shear group (p<0.05).
Conclusion: The noise produced by the oscillating saw was associated with an increased anxiety level in children undergoing cast removal. Cast shear is a simple and inexpensive instrument that can be used for cast removal in overly anxious children.
Decoding death by unknown causes using post mortem image-guided virtopsy: A review of recent literature and the Malaysian experience

Tawfiq Zyoud TY, Abdul Rashid SN, Suppiah S, Abdul Rahim E, Mahmud R

Med J Malaysia, 2020 07;75(4):411-418.
PMID: 32724006

INTRODUCTION: Autopsy is one of the most important approaches to identify clearly the exact cause of death, whether it was due to natural causes, sudden death, or traumatic. Various studies have been done in different countries regarding ways to improve the diagnosis during autopsy. The imaging approach is one of the methods that has been used to complement autopsy findings and to enhance the diagnosis for achieving the most accurate post-mortem diagnosis. The aim of this study is to identify the role of imaging modalities that complement routine autopsy and correlate the findings of diagnostic imaging that can help improve the accuracy of diagnosing the cause of death.
METHODS: We sourced articles from Scopus, Ovid and PubMed databases for journal publications related to post-mortem diagnostic imaging. We highlight the most relevant full articles in English that explain the type of modality that was utilised and the added value it provided for diagnosing the cause of death.
RESULTS: Minimally invasive autopsies assisted by imaging modalities added a great benefit to forensic medicine, and supported conventional autopsy. In particular the role of post mortem computed tomography (PMCT), post mortem computed tomography angiography (PMMR) and positron emission tomography computed tomography (PMCTA) that have incremental benefits in diagnosing traumatic death, fractures, tissue injuries, as well as the assessment of body height or weight for corpse identification.
CONCLUSION: PMCT and PMMR, with particular emphasis on PMCTA, can provide higher accuracy than the other modalities. They can be regarded as indispensable methods that should be applied to the routine autopsy protocol, thus improving the findings and accuracy of diagnosing the cause of death.
Fulltext Florid papillomatosis of the nipple

Dinesh BJ, Hayati F, Azizan N, Abdul Rashid NF

BMJ Case Rep, 2019 Sep 18;12(9).
PMID: 31537599 DOI: 10.1136/bcr-2019-231516

Florid papillomatosis (FP) of the nipple, or nipple adenoma, is a rare breast tumour, affecting middle-aged group population. A 46-year-old woman presented to us with a cauliflower-like FP of the right nipple with no blood stained discharge or breast lump. FP can be mistaken clinically for Paget's disease and occasionally misinterpreted as invasive ductal or intraductal carcinoma. Extensive intervention, correct diagnosis and prompt treatment are essential. Any breast pathology requires triple assessment including FP of the nipple. Once the diagnosis of ductal carcinoma is excluded, simple complete excision can be undertaken. This is to ensure complete obliteration of disease recurrence and preservation of cosmetic result. We discuss the pathology and psychosocial aspects of FP.
The Rubber Stopper: A Simple and Inexpensive Technique to Prevent Pin Tract Infection following Kirschner Wiring of Supracondylar Fractures of Humerus in Children

Santy JE, Kamal J, Abdul-Rashid AH, Ibrahim S

Malays Orthop J, 2015 Jul;9(2):13-16.
PMID: 28435603 MyJurnal DOI: 10.5704/MOJ.1507.006

Percutaneous pinning after closed reduction is commonly used to treat supracondylar fractures of the humerus in children. Minor pin tract infections frequently occur. The aim of this study was to prevent pin tract infections using a rubber stopper to reduce irritation of the skin against the Kirschner (K) wire following percutaneous pinning. Between July 2011 and June 2012, seventeen children with closed supracondylar fracture of the humerus of Gartland types 2 and 3 were treated with this technique. All patients were treated with closed reduction and percutaneous pinning and followed up prospectively. Only one patient, who was a hyperactive child, developed pin tract infection due to softening of the plaster slab. We found using the rubber stopper to be a simple and inexpensive method to reduce pin tract infections following percutaneous pinning.
A Massive Hemothorax in a Pregnant Woman: Role of Interventional Radiology

Md Noh MSF, Abdul Rashid AM, Abdul Rahim E

J Bronchology Interv Pulmonol, 2018 07;25(3):e30-e32.
PMID: 29944591 DOI: 10.1097/LBR.0000000000000456
Fulltext Survival analysis of osteosarcoma patients: A 15-year experience

Yasin NF, Abdul Rashid ML, Ajit Singh V

J Orthop Surg (Hong Kong), 2020 2 23;28(1):2309499019896662.
PMID: 32077796 DOI: 10.1177/2309499019896662

INTRODUCTION: Management of osteosarcoma has evolved considerably for the past two decades and there have been changes of practices especially pertaining to chemotherapy regime. This is a review of our cases in the past 15 years.
METHOD: This is a retrospective survival analysis study of 128 patients treated at University Malaya Medical Centre (UMMC) from 1997 to 2011.
RESULTS: There were 80 (62.5%) male and 48 (37.5%) female patients with the median age being 15 (5-59). Majority had osteosarcoma of extremities (94.5%). More than 60% patients developed metastasis throughout the course of treatment with 39% presenting with lung metastasis. Osteoblastic osteosarcoma was the commonest subtype (65.6%). Of the 109 patients treated surgically, 84 patients (65.6%) underwent limb salvage surgery while the rest underwent amputation. Seventy-one per cent of patients completed treatment with local recurrence rate of 22.7%. The 5-year and 10-year survival rates were 56.31% (95% CI: 46.20, 65.24) and 22.33% (95% CI: 14.86, 30.76), respectively. The 5-year event-free survival was 52.94% (95% CI: 41.83, 62.87). In multivariate analysis, the independent prognostic factors were presence of metastasis and completion of treatment for both 5-year and 10-year overall survival. Good histological response was only significant for multivariate analysis at 5 years. Patients with metastasis had a hazard ratio of 20.4 at 5 years and 3.26 at 10 years.
CONCLUSION: Overall survival rate for osteosarcoma patients at our centre was comparably higher than other centres in the region. Two independent risk factors for survival are metastatic status and completion of treatment. A standardized chemotherapy regime is essential for long-term survival.
Fulltext A case of anti-N-methyl-d-aspartate receptor encephalitis

Abdul Rashid AM, Mohamad Mokhtar E, Md Noh MSF

SAGE Open Med Case Rep, 2020;8:2050313X20926431.
PMID: 32547761 DOI: 10.1177/2050313X20926431

Anti-N-methyl-d-aspartate receptor encephalitis is characterized by the clinical manifestation of neuropsychiatric symptoms, predominantly affecting young adults, and frequently associated with neoplasms. It is the second most common cause of autoimmune and paraneoplastic encephalitis. Early diagnosis is often missed, as patients are commonly diagnosed with psychiatric illnesses and are treated with antipsychotics - which rarely gives complete resolution of symptoms. Herein, we discuss a patient with mixed clinical, imaging, electroencephalogram, and laboratory findings, with an eventual diagnosis of anti-N-methyl-d-aspartate receptor encephalitis requiring immunotherapy and operative intervention.
Tuberculous (TB) myelopathy associated with longitudinally extensive lesion: A case report

Noh MSF, Bahari N, Abdul Rashid AM

J Neuroradiol, 2021 Nov;48(6):453-455.
PMID: 31837378 DOI: 10.1016/j.neurad.2019.12.002
Fulltext A case report of juvenile giant fibroadenoma of the breast: How common?

Mohd Firdaus CA, Norjazliney AJ, Abdul Rashid NF

Ci Ji Yi Xue Za Zhi, 2017 10 5;29(3):177-179.
PMID: 28974914 DOI: 10.4103/tcmj.tcmj_64_17

Breast lesions are rare prepubescents. The majority of breast lesions in this age group are benign. The most common of these rare lesions is juvenile fibroadenoma, which accounts for only 0.5% of all fibroadenomas. It is uncommon to have a palpable lesion in juveniles as very small lesions show obvious asymmetry. Fibroadenomas can grow to a large size, and surgical intervention is cosmetically challenging, especially in achieving symmetry in a developing breast. A 12-year-old girl presented with right breast swelling associated with tenderness. The mass had initially been small on self-discovery 1 year previously and grew with time. There was no overlying skin changes or any significant risk factors for breast malignancy. Triple assessment showed features of fibroadenoma, but we were unable to rule out a phyllodes tumor. She subsequently underwent excision biopsy of the right breast lesion for symptomatic control and histopathology examination (HPE) of the lesion. The HPE report confirmed the diagnosis of fibroadenoma. The patient recovered well postoperatively with no complications. Juvenile breast lesions are rare, and it is a challenge to provide an adolescent with the best treatment in terms of clinical and psychological care. A surgical approach requires meticulous planning to ensure a fine balance between adequate resection and the best cosmetic outcome for a developing breast.
Fulltext Lipid Alterations in Glioma: A Systematic Review

Abdul Rashid K, Ibrahim K, Wong JHD, Mohd Ramli N

Metabolites, 2022 Dec 16;12(12).
PMID: 36557318 DOI: 10.3390/metabo12121280

Gliomas are highly lethal tumours characterised by heterogeneous molecular features, producing various metabolic phenotypes leading to therapeutic resistance. Lipid metabolism reprogramming is predominant and has contributed to the metabolic plasticity in glioma. This systematic review aims to discover lipids alteration and their biological roles in glioma and the identification of potential lipids biomarker. This systematic review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Extensive research articles search for the last 10 years, from 2011 to 2021, were conducted using four electronic databases, including PubMed, Web of Science, CINAHL and ScienceDirect. A total of 158 research articles were included in this study. All studies reported significant lipid alteration between glioma and control groups, impacting glioma cell growth, proliferation, drug resistance, patients' survival and metastasis. Different lipids demonstrated different biological roles, either beneficial or detrimental effects on glioma. Notably, prostaglandin (PGE2), triacylglycerol (TG), phosphatidylcholine (PC), and sphingosine-1-phosphate play significant roles in glioma development. Conversely, the most prominent anti-carcinogenic lipids include docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and vitamin D3 have been reported to have detrimental effects on glioma cells. Furthermore, high lipid signals were detected at 0.9 and 1.3 ppm in high-grade glioma relative to low-grade glioma. This evidence shows that lipid metabolisms were significantly dysregulated in glioma. Concurrent with this knowledge, the discovery of specific lipid classes altered in glioma will accelerate the development of potential lipid biomarkers and enhance future glioma therapeutics.
Fulltext QFD-Based Research on Sustainable User Experience Optimization Design of Smart Home Products for the Elderly: A Case Study of Smart Refrigerators

Li Y, Ghazilla RAR, Abdul-Rashid SH

Int J Environ Res Public Health, 2022 Oct 22;19(21).
PMID: 36360620 DOI: 10.3390/ijerph192113742

In the current situation of global aging, the current market shortage of age-appropriate smart home products and the recent epidemic have led to greater isolation of the elderly, seriously affecting their physical and mental health. In order to optimize the sustainable user experience of the elderly when using smart home products, this paper proposes a research method based on Quality Function Deployment (QFD) for the optimal design of user experience of smart home products for the elderly, taking the design of age-appropriate home smart refrigerators as an example. Firstly, based on the results of market research and user interviews, the requirements of smart refrigerators for the elderly are screened and integrated, and the Kano model is used to prioritize these needs, resulting in the identification of important features needed in smart refrigerators for the elderly. Secondly, based on QFD, user requirements are transformed into design requirements, and a quality house model is established to ascertain the degree of importance of each design requirement through user ratings so as to obtain the key requirements as the theoretical basis for the solution design. Finally, optional solutions are generated for concept evaluation based on PUGH concept selection, comparing the advantages and disadvantages of the solutions and recombining them into an evaluation to determine the best solution. The quantitative evaluation of the four solutions reveals that Solution A has the highest score of 117.358, followed by Solution D with 113.259, Solution B with 96.415, and Solution C with 85.511, which is the lowest. The scoring allows the best design solution to be selected and applied to product development. The results show that the introduction of the Kano model and PUGH concept selection into QFD can be effectively used as a research method for optimizing the user experience of smart refrigerators for the elderly, and a corresponding design strategy for sustainable user experience optimization is proposed. The method and strategy provide guidance for the innovative design of new smart home products.
Numerical model for enhancing stimulated Brillouin scattering in optical microfibers

Yeap SH, Emami SD, Abdul-Rashid HA

F1000Res, 2021;10:521.
PMID: 37745939 DOI: 10.12688/f1000research.51029.2

Stimulated Brillouin scattering (SBS) is useful, among others for generating slow light, sensing and amplification. SBS was previously viewed as a poor method due to the limitation on optical power in high-powered photonic applications. However, considering the many possible applications using SBS, it is now of interest to enhance SBS in areas of Brillouin frequency shift together with Brillouin Gain. A numerical model, using a fully vectorial approach, by employing the finite element method, was developed to investigate methods for enhancing SBS in optical fiber. This paper describes the method related to the numerical model and discusses the analysis between the interactions of longitudinal, shear and hybrid acoustic modes; and optical modes in optical fiber. Two case studies were used to demonstrate this. Based on this numerical model, we report the influence of core radius, clad radius and effective refractive index on the Brillouin frequency shift and gain. We observe the difference of Brillouin shift frequency between a normal silica optical fiber and that of a microfiber - a uniformed silica fiber of a much smaller core and cladding dimensions where nonlinearities are higher. Also observed, the different core radii used and their respective Brillouin shift. For future work, the COMSOL model can also be used for the following areas of research, including simulating "surface Brillouin shift" and also to provide in-sights to the Brillouin shift frequency vB of various structures of waveguides, e.g circular, and triangular, and also to examine specialty fibers, e.g. Thulium and Chalcogenide doped fibers, and their effects on Brillouin shift frequency.

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