Displaying publications 121 - 140 of 174 in total

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  1. Sex estimation of Malaysian sub-adults using craniometrics: A computed tomography study
    Syed Mohd Hamdan SN, Rahmat RA, Abdul Razak F, Abd Kadir KA, Mohd Faizal Abdullah ER, Ibrahim N
    Leg Med (Tokyo), 2023 Sep;64:102275.
    PMID: 37229938 DOI: 10.1016/j.legalmed.2023.102275
    Sex estimation is crucial in biological profiling of skeletal human remains. Methods used for sex estimation in adults are less effective for sub-adults due to varied cranium patterns during the growth period. Hence, this study aimed to develop a sex estimation model for Malaysian sub-adults using craniometric measurements obtained through multi-slice computed tomography (MSCT). A total of 521 cranial MSCT dataset of sub-adult Malaysians (279 males, 242 females; 0-20 years old) were collected. Mimics software version 21.0 (Materialise, Leuven, Belgium) was used to construct three-dimensional (3D) models. A plane-to-plane (PTP) protocol was utilised to measure 14 selected craniometric parameters. Discriminant function analysis (DFA) and binary logistic regression (BLR) were used to statistically analyze the data. In this study, low level of sexual dimorphism was observed in cranium below 6 years old. The level was then increased with age. For sample validation data, the accuracy of DFA and BLR in estimating sex improved with age from 61.6% to 90.3%. All age groups except 0-2 and 3-6 showed high accuracy percentage (≥75%) when tested using DFA and BLR. DFA and BLR can be utilised to estimate sex for Malaysian sub-adult using MSCT craniometric measurements. However, BLR showed higher accuracy than DFA in sex estimation of sub-adults.
    Matched MeSH terms: Skull/anatomy & histology
  2. Relevance of Whitnall's tubercle and auditory meatus in diagnosing exclusions during skull-photo superimposition
    Jayaprakash PT, Hashim N, Yusop RA
    Forensic Sci Int, 2015 Aug;253:131.e1-10.
    PMID: 26103927 DOI: 10.1016/j.forsciint.2015.04.026
    Video vision mixer based skull-photo superimposition is a popular method for identifying skulls retrieved from unidentified human remains. A report on the reliability of the superimposition method suggested increased failure rates of 17.3 to 32% to exclude and 15 to 20% to include skulls while using related and unrelated face photographs. Such raise in failures prompted an analysis of the methods employed for the research. The protocols adopted for assessing the reliability are seen to vary from those suggested by the practitioners in the field. The former include overlaying the skull- and face-images on the basis of morphology by relying on anthropometric landmarks on the front plane of the face-images and evaluating the goodness of match depending on mix-mode images; the latter consist of orienting the skull considering landmarks on both the eye and ear planes of the face- and skull-images and evaluating the match utilizing images seen in wipe-mode in addition to those in mix-mode. Superimposition of a skull with face-images of five living individuals in two sets of experiments, one following the procedure described for the research on reliability and the other applying the methods suggested by the practitioners has shown that overlaying the images on the basis of morphology depending on the landmarks on the front plane alone and assessing the match in mix-mode fails to exclude the skull. However, orienting the skull relying on the relationship between the anatomical landmarks on the skull- and face-images such as Whitnall's tubercle and exocanthus in the front (eye) plane and the porion and tragus in the rear (ear) plane as well as assessing the match using wipe-mode images enables excluding that skull while superimposing with the same set of face-images.
    Matched MeSH terms: Skull/anatomy & histology
  3. Study on the performance of different craniofacial superimposition approaches (I)
    Ibáñez O, Vicente R, Navega DS, Wilkinson C, Jayaprakash PT, Huete MI, et al.
    Forensic Sci Int, 2015 Dec;257:496-503.
    PMID: 26060056 DOI: 10.1016/j.forsciint.2015.05.030
    As part of the scientific tasks coordinated throughout The 'New Methodologies and Protocols of Forensic Identification by Craniofacial Superimposition (MEPROCS)' project, the current study aims to analyse the performance of a diverse set of CFS methodologies and the corresponding technical approaches when dealing with a common dataset of real-world cases. Thus, a multiple-lab study on craniofacial superimposition has been carried out for the first time. In particular, 26 participants from 17 different institutions in 13 countries were asked to deal with 14 identification scenarios, some of them involving the comparison of multiple candidates and unknown skulls. In total, 60 craniofacial superimposition problems divided in two set of females and males. Each participant follow her/his own methodology and employed her/his particular technological means. For each single case they were asked to report the final identification decision (either positive or negative) along with the rationale supporting the decision and at least one image illustrating the overlay/superimposition outcome. This study is expected to provide important insights to better understand the most convenient characteristics of every method included in this study.
    Matched MeSH terms: Skull/anatomy & histology*
  4. Fulltext Surface Reconstruction from Parallel Curves with Application to Parietal Bone Fracture Reconstruction
    Majeed A, Mt Piah AR, Ridzuan Yahya Z
    PLoS One, 2016;11(3):e0149921.
    PMID: 26967643 DOI: 10.1371/journal.pone.0149921
    Maxillofacial trauma are common, secondary to road traffic accident, sports injury, falls and require sophisticated radiological imaging to precisely diagnose. A direct surgical reconstruction is complex and require clinical expertise. Bio-modelling helps in reconstructing surface model from 2D contours. In this manuscript we have constructed the 3D surface using 2D Computerized Tomography (CT) scan contours. The fracture part of the cranial vault are reconstructed using GC1 rational cubic Ball curve with three free parameters, later the 2D contours are flipped into 3D with equidistant z component. The constructed surface is represented by contours blending interpolant. At the end of this manuscript a case report of parietal bone fracture is also illustrated by employing this method with a Graphical User Interface (GUI) illustration.
    Matched MeSH terms: Skull Fractures/surgery
  5. Study on the performance of different craniofacial superimposition approaches (II): Best practices proposal
    Damas S, Wilkinson C, Kahana T, Veselovskaya E, Abramov A, Jankauskas R, et al.
    Forensic Sci Int, 2015 Dec;257:504-508.
    PMID: 26482539 DOI: 10.1016/j.forsciint.2015.07.045
    Craniofacial superimposition, although existing for one century, is still a controversial technique within the scientific community. Objective and unbiased validation studies over a significant number of cases are required to establish a more solid picture on the reliability. However, there is lack of protocols and standards in the application of the technique leading to contradictory information concerning reliability. Instead of following a uniform methodology, every expert tends to apply his own approach to the problem, based on the available technology and deep knowledge on human craniofacial anatomy, soft tissues, and their relationships. The aim of this study was to assess the reliability of different craniofacial superimposition methodologies and the corresponding technical approaches to this type of identification. With all the data generated, some of the most representative experts in craniofacial identification joined in a discussion intended to identify and agree on the most important issues that have to be considered to properly employ the craniofacial superimposition technique. As a consequence, the consortium has produced the current manuscript, which can be considered the first standard in the field; including good and bad practices, sources of error and uncertainties, technological requirements and desirable features, and finally a common scale for the craniofacial matching evaluation. Such a document is intended to be part of a more complete framework for craniofacial superimposition, to be developed during the FP7-founded project MEPROCS, which will favour and standardize its proper application.
    Matched MeSH terms: Skull/anatomy & histology*
  6. Rhabdomyosarcoma of the middle ear and mastoid in children
    Said H, Phang KS, Razi A, Khuzaiyah R, Patawari PH, Esa R
    J Laryngol Otol, 1988 Jul;102(7):614-9.
    PMID: 3411216
    Three cases of embryonal rhabdomyosarcoma in the middle ear and mastoid in children are presented. Diagnosis was confirmed by histopathology. A multidisciplinary approach employing surgery, chemotherapy and radiation therapy is the method of choice in the management of this rare and highly lethal condition.
    Matched MeSH terms: Skull Neoplasms/pathology*; Skull Neoplasms/therapy
  7. Diabetic artefacts in forensic practice
    Murty OP
    J Forensic Leg Med, 2009 May;16(4):218-23.
    PMID: 19329080 DOI: 10.1016/j.jflm.2008.07.010
    A case is presented where confusion arose about skin lesions and whether they were diabetic or electrical in origin. The deceased was a known diabetic and hypertensive man. A middle-aged person in early fifties was found unconscious in the cell and judicial autopsy was performed. He was facing trial for capital punishment of being allegedly involved in drug trafficking and money laundering. He had few marks over his fingers and foot which were considered to be electric marks produced in electric torture. also had fracture of skull and ischemic necrosis of right side of cerebrum; and contrecoup lesions. Findings are documented with photographs of the lesions. The article also depicts photographs of the scene where the victim had fallen and sustained skull fracture.
    Matched MeSH terms: Skull Fractures/etiology; Skull Fractures/pathology
  8. Fulltext Methyl methacrylate cranioplasty
    Azmi A, Latiff AZ, Johari A
    Med J Malaysia, 2004 Aug;59(3):418-21.
    PMID: 15727391
    We conducted a prospective study in order to audit our experience of repairing cranial defects using Methyl methacrylate. This included a total of 49 patients undergoing cranioplasty using methyl methacrylate, of which 45 were males and 4 females. The age of patients at the time of surgery ranged from 16 to 40 years old, with an average of 24 years. Malays were the majority (67%), followed by Chinese (23%) and Indian (10%). Cranial defects were mainly caused by motor vehicle accident (94%), while gunshot wounds, industrial accidents and tumours, each contribute 2%. Bone flaps were commonly removed during previous surgery related to traumatic subdural haemorrhage (33%), contusion (21%) and intracerebral haemorrhage (14%). The size of cranial defects ranged from 28 cm2 to 440 cm2, with an average of 201 cm2. Most had right sided (55%) and lateral defects [temporoparietal (52%) followed by temporal (16%), frontal (16%), frontotemporal (14%) and occipital (2%)]. Duration of surgery ranged from 70 to 275 minutes, with an average of 135 minutes. Nine of 12 patients (75%) with neurological disability had some improvement while 85% of symptomatic patients had symptoms improvement after cranioplasty. The infection rate in this series was 4%.
    Matched MeSH terms: Skull/abnormalities; Skull/surgery*
  9. Fulltext Local application of osteoprotegerin-chitosan gel in critical-sized defects in a rabbit model
    Jayash SN, Hashim NM, Misran M, Baharuddin NA
    PeerJ, 2017;5:e3513.
    PMID: 28674665 DOI: 10.7717/peerj.3513
    BACKGROUND: Osteoprotegerin (OPG) is used for the systemic treatment of bone diseases, although it has many side effects. The aim of this study was to investigate a newly formulated OPG-chitosan gel for local application to repair bone defects. Recent studies have reported that immunodetection of osteopontin (OPN) and osteocalcin (OC) can be used to characterise osteogenesis and new bone formation.

    METHODS: The osteogenic potential of the OPG-chitosan gel was evaluated in rabbits. Critical-sized defects were created in the calvarial bone, which were either left unfilled (control; group I), or filled with chitosan gel (group II) or OPG-chitosan gel (group III), with rabbits sacrificed at 6 and 12 weeks. Bone samples from the surgical area were decalcified and treated with routine histological and immunohistochemical protocols using OC, OPN, and cathepsin K (osteoclast marker) antibodies. The toxicity of the OPG-chitosan gel was evaluated by biochemical assays (liver and kidney function tests).

    RESULTS: The mean bone growth in defects filled with the OPG-chitosan gel was significantly higher than those filled with the chitosan gel or the unfilled group (p 

    Matched MeSH terms: Skull
  10. Fulltext Importance of clinical and morphological correlations in diagnosing Langerhans cell histiocytosis
    Seb, Omayma, Fauzana, K., Aisyah, M.R., Noraidah, M., Noor Hamidah, H.
    Medicine & Health, 2018;13(1):220-226.
    MyJurnal
    Langerhans cell histiocytosis (LCH) is a clonal histiocytic disorder. The variable clinical manifestations from isolated bone lesion to multisystem disease can cause difficulties and delay in diagnosis. We report a 2 years and 8 months-old girl who presented with a 2 weeks history of persistent fever and weight loss associated with progressive abdominal distension. Physical examination revealed pallor, bilateral proptosis, seaborrheic dermatitis over the scalp and hepatosplenomegaly. Skull X-ray demonstrated multiple lytic lesions at the base and the skull vault. Bone marrow morphology showed numerous abnormal Langerhans cells (LCs) and foamy macrophages. The trephine immunohistochemistry (IHC) stains for CD1a, S-100 and CD68 were inconclusive. The diagnosis of multisystem Langerhans cell histiocytosis (MS-LCH) in this patient was based on the clinical presentation, radiological and morphological analysis. She subsequently received chemotherapy and currently she is on maintenance therapy with a good clinical response. LCH is a rare disease and although the IHC was inconclusive, the correlation of clinical, radiological and morphological data are essential for the diagnosis.
    Matched MeSH terms: Skull
  11. Fulltext Evaluation of the Performance of Helmet Prototypes Fabricated from Acrylonitrile Butadiene Styrene Composites Filled with Natural Resource
    Nikmatin S, Hermawan B, Irmansyah I, Indro MN, Kueh ABH, Syafiuddin A
    Materials (Basel), 2018 Dec 22;12(1).
    PMID: 30583516 DOI: 10.3390/ma12010034
    The performance of helmet prototypes fabricated from acrylonitrile butadiene styrene composites filled with oil palm empty fruit bunch fibers was evaluated. The fibers were produced using a milling procedure, while the composites were fabricated using a single-screw extrusion. The physical characteristics of the produced fibers, which are water content, size, and density, were investigated. In addition, the mechanical properties of the produced helmets, including shock absorption, yield stress, frequency, and head injury criterion (HIC), were examined. The impact strength of the produced helmets increases with the rise of filler content. In addition, the helmets were also able to withstand a considerable pressure such that the transmitted pressure was far under the maximum value acceptable by the human skull. The present work also found that HICs exhibited by the investigated helmet prototypes fulfill all the practical guidelines as permitted by the Indonesian government. In terms of novelty, such innovation can be considered the first invention in Indonesia since the endorsement of the use of motorcycle helmets.
    Matched MeSH terms: Skull
  12. Fulltext Untreated Giant Macroprolactinoma with Chronic Cerebrospinal Fluid Leakage: An Unusual Complication
    Mad Naser MN, Aziz NA, Karim NKA
    Case Rep Endocrinol, 2019;2019:4825357.
    PMID: 30766735 DOI: 10.1155/2019/4825357
    Macroprolactinoma has the potential to cause base of skull erosion and often extends into the sphenoid sinus. Rapid shrinkage of this invasive tumor following dopamine agonist therapy has been postulated to cause unplugging of the eroded area, leading to cerebrospinal fluid leakage. To the best of our knowledge, the occurrence of spontaneous cerebrospinal fluid leak in treatment-naive prolactinomas is very rare, the majority of which involve undiagnosed macroprolactinomas. We describe here a lady presented late with giant macroprolactinoma, complicated by cerebrospinal fluid leakage. This case raised the dilemma in the management pertaining to the role of either pharmacotherapy or surgical intervention, or combination of both. As she strictly refused surgery, she was treated with bromocriptine which was later changed to cabergoline. On follow-up, there was cessation of cerebrospinal fluid leak, marked reduction of serum prolactin level, and imaging evidence of tumor shrinkage. The majority of patients with medically induced cerebrospinal fluid leakage will require surgical procedures to overcome this complication; however, there are isolated cases of leakage resolution on continuing dopamine agonist therapy while awaiting surgery. The use of dopamine agonist does not necessarily cause worsening of cerebrospinal fluid leakage and instead may produce spontaneous resolution as in this case.
    Matched MeSH terms: Skull Base
  13. Fulltext In Situ Controlled Surface Microstructure of 3D Printed Ti Alloy to Promote Its Osteointegration
    Shan L, Kadhum AAH, Al-Furjan MSH, Weng W, Gong Y, Cheng K, et al.
    Materials (Basel), 2019 Mar 10;12(5).
    PMID: 30857349 DOI: 10.3390/ma12050815
    It is well known that three-dimensional (3D) printing is an emerging technology used to produce customized implants and surface characteristics of implants, strongly deciding their osseointegration ability. In this study, Ti alloy microspheres were printed under selected rational printing parameters in order to tailor the surface micro-characteristics of the printed implants during additive manufacturing by an in situ, controlled way. The laser path and hatching space were responsible for the appearance of the stripy structure (S), while the bulbous structure (B) and bulbous⁻stripy composite surface (BS) were determined by contour scanning. A nano-sized structure could be superposed by hydrothermal treatment. The cytocompatibility was evaluated by culturing Mouse calvaria-derived preosteoblastic cells (MC3T3-E1). The results showed that three typical microstructured surfaces, S, B, and BS, could be achieved by varying the 3D printing parameters. Moreover, the osteogenic differentiation potential of the S, B, and BS surfaces could be significantly enhanced, and the addition of nano-sized structures could be further improved. The BS surface with nano-sized structure demonstrated the optimum osteogenic differentiation potential. The present research demonstrated an in situ, controlled way to tailor and optimize the surface structures in micro-size during the 3D printing process for an implant with higher osseointegration ability.
    Matched MeSH terms: Skull
  14. Patient-Specific Reconstruction Utilizing Computer Assisted 3D Modelling for Partial Bone Flap Defect in Hybrid Cranioplasty
    Low PH, Abdullah JY, Abdullah AM, Yahya S, Idris Z, Mohamad D
    J Craniofac Surg, 2019 Jun 28.
    PMID: 31261343 DOI: 10.1097/SCS.0000000000005713
    PURPOSE: Decompressive craniectomy is a life-saving procedure in the setting of malignant brain swelling. Patients who survive require cranioplasty for anatomical reconstruction and cerebral protection. Autologous cranioplasty remains the commonest practice nowadays, but partial bone flap defects are frequently encountered. The authors, therefore, seek to develop a new technique of reconstruction for cranioplasty candidate with partial bone flap defect utilizing computer-assisted 3D modeling and printing.

    METHODS: A prospective study was conducted to evaluate the outcome of a new reconstruction technique that produces patient-specific hybrid polymethyl methacrylate-autologous cranial implant. Computer-assisted 3D modeling and printing was utilized to produce patient-specific molds, which allowed real-time reconstruction of bone flap with partial defect intra-operatively.

    RESULTS: Outcome assessment for 11 patients at 6 weeks and 3 months post-operatively revealed satisfactory implant alignment with favorable cosmesis. The mean visual analog scale for cosmesis was 91. Mean implant size was 50cm, and the mean duration of intra-operative reconstruction was 30 minutes. All of them revealed improvement in quality of life following surgery as measured by the SF-36 score. Cost analysis revealed that this technique is more cost-effective compared to customized cranial prosthesis.

    CONCLUSION: This new technique and approach produce hybrid autologous-alloplastic bone flap that resulted in satisfactory implant alignment and favorable cosmetic outcome with relatively low costs.

    Matched MeSH terms: Skull
  15. Candida Skull Base Osteomyelitis: a Case Report and Literature Review
    Krishnamoorthy M, Othman NAN, Hassan NEB, Hitam SB
    Acta Medica (Hradec Kralove), 2020;63(2):82-85.
    PMID: 32771074 DOI: 10.14712/18059694.2020.22
    Skull base osteomyelitis (SBO) also commonly known as malignant otitis externa was first described by Meltzer and Kelemen in 1959. Prior to the advent of the antibiotic era, this disease carried a poor prognosis with significant morbidity. It often proved fatal with mortality rates as high as 50%. Commonly seen in the immunocompromised patients, diabetes mellitus is an important associated comorbidity in the pathophysiologic development of this disease. Treatment is instituted by medical therapy with surgery having a limited role. Surgical intervention has a limited role, for example, in fungal SBO. Such cases may require local debridement and intraoperative tissue biopsies for histopathologic confirmation. This is to demonstrate fungal invasion into the skull base, as well as to exclude other sinister differential diagnoses like squamous cell carcinoma of temporal bone. In this case report, we present a rare case of candida SBO and the literature review.
    Matched MeSH terms: Skull Base
  16. Fulltext A rare case of traumatic bilateral sixth cranial nerve palsy
    Hamidon, B.B., Md Shariful, H.S., Nasaruddin, M.Z.
    International Medical Journal Malaysia, 2012;11(2):50-52.
    MyJurnal
    Traumatic bilateral sixth cranial nerve palsy is a rare condition which is typically associated with additional intracranial, skull, and cervical spine injuries. We describe a case of complete bilateral sixth nerve palsy in a 28-year-old female patient after an alleged motor vehicle accident. She had altered level of consciousness but no intracranial lesion or associated skull or cervical spine fracture was detected. In this case, we discussed the differential diagnoses, initial workup, and possible treatment options in cases of traumatic 6th nerve palsy.
    Matched MeSH terms: Skull
  17. Fulltext Facial profile and maxillary arch dimensions in unilateral cleft lip and palate children in the mixed dentition stage
    Gopinath VK, Samsudin AR, Mohd Noor SNF, Mohamed Sharab HY
    Eur J Dent, 2017 4 25;11(1):76-82.
    PMID: 28435370 DOI: 10.4103/ejd.ejd_238_16
    OBJECTIVES: The aim of this study was to evaluate the vertical and sagittal facial profile and maxillary arch width, depth, and length of patients with unilateral cleft lip and palate (UCLP) and to compare them with healthy noncleft children in the mixed dentition stage (7-13 years).

    MATERIALS AND METHODS: This study is conducted at Hospital Universiti Sains Malaysia. UCLP group comprised 48 patients with nonsyndromic UCLP who have had the lip and palate repaired, whereas the control group comprised 48 healthy noncleft cases. The lateral cephalometrics measurements were used to determine the vertical height, sagittal depth of the face, and cranial base length and angle. Maxillary arch dimensions were measured on the study cast including arch width, depth, and length.

    RESULTS: Vertical facial height and sagittal depth measurements showed a significant decrease (P < 0.05) in the mean growth pattern in UCLP group. The anterior cranial base length (S-N) was shorter in UCLP children (P < 0.001), while Ba-N length had no significant difference (P = 0.639). Nasion-Sella Tursica-Basion angle was significantly higher in the UCLP group (P = 0.016). Dental arch width with reference to canine-to-canine and first premolar-to- first premolar distance was significantly larger in control (P = 0.001).

    CONCLUSION: Mean vertical and sagittal facial dimensions in the UCLP children who do not undergo orthodontic treatment are significantly lesser in all directions of growth than healthy noncleft children. The maxillary dental arch had a normal depth but constricted in width and arch length.

    Matched MeSH terms: Skull Base
  18. Fulltext Subjective preference of new prototypes safety helmets device among palm oil plantation harvesters in Sandakan, Sabah
    Nur Al - Izzah binti Nazri, Shamsul Bahri Mohd Tamrin, Dayana Hazwani Mohd Suadi Nata, Ng Yee Guan
    Malaysian Journal of Medicine and Health Sciences, 2020;16(101):31-37.
    MyJurnal
    Introduction: Safety helmets are one of the personal protective equipment (PPE) that to decrease the impact of any falling object to the skull and to avoid head and brain injury by many industries, including palm oil plantation. Nev- ertheless, the level on the usage of the current safety helmet is very low due to a few factors that lead to the discom- fort. Among the common issues for the non-compliance of safety helmets are their discomfort, ventilation, weight and safety. This study aims to determine subjective preference of the new prototypes’ safety helmets device among palm oil plantation harvesters. Methods: A cross-sectional study conducted among 124 harvesters in three palm oil plantations located in Sabah, Malaysia. A set of questionnaires used to collect data on their socio-demographic background, perceptions toward existing safety helmets and their subjective preference of new safety helmets pro- totypes. Apart from that, six harvesters were randomly choosing to attend an interview session for qualitative study. Results: The descriptive analysis indicate that among the emphasized issues regarding non-compliance of existing safety helmet were due to discomfort (66.1%), poor ventilation (97.6%), load of safety helmet (83.3%) and safety issues (68.5%). In terms of new safety helmets prototypes, 72.6% of the harvesters preferred Design C to be worn for work in the plantation. Conclusion: It can be suggested that the existing safety helmet is uncomfortable and was not design ergonomically namely loose size and discomfort. Design C was the most preferred to be worn for work in the palm oil plantation.
    Matched MeSH terms: Skull
  19. Fulltext The use of SPECT-CT improves accuracy of post-radioiodine therapy imaging and changes the management strategy in a case of advanced follicular thyroid carcinoma
    Wong TH, Amir Hassan SZ
    Med J Malaysia, 2015 Dec;70(6):356-7.
    PMID: 26988209
    This is a case of follicular thyroid carcinoma with extensive lung, bone and brain metastases. Multi-modality treatments including total thyroidectomy, modified radical neck dissection, cranial radiotherapy and Iodine-131 (RAI) therapy were instituted. Post RAI therapy planar whole body scan showed RAI avid metastases in the skull, cervical spine, bilateral lungs and abdomen. With the use of SPECTCT imaging, rare adrenal metastasis and additional rib metastasis were identified. Besides, management strategy was altered due to detection of non-RAI avid brain and lung metastatic lesions.
    Matched MeSH terms: Skull
  20. Fulltext Sound signatures and production mechanisms of three species of pipefishes (Family: Syngnathidae)
    Lim AC, Chong VC, Wong CS, Muniandy SV
    PeerJ, 2015;3:e1471.
    PMID: 26734507 DOI: 10.7717/peerj.1471
    Background. Syngnathid fishes produce three kinds of sounds, named click, growl and purr. These sounds are generated by different mechanisms to give a consistent signal pattern or signature which is believed to play a role in intraspecific and interspecific communication. Commonly known sounds are produced when the fish feeds (click, purr) or is under duress (growl). While there are more acoustic studies on seahorses, pipefishes have not received much attention. Here we document the differences in feeding click signals between three species of pipefishes and relate them to cranial morphology and kinesis, or the sound-producing mechanism. Methods. The feeding clicks of two species of freshwater pipefishes, Doryichthys martensii and Doryichthys deokhathoides and one species of estuarine pipefish, Syngnathoides biaculeatus, were recorded by a hydrophone in acoustic dampened tanks. The acoustic signals were analysed using time-scale distribution (or scalogram) based on wavelet transform. A detailed time-varying analysis of the spectral contents of the localized acoustic signal was obtained by jointly interpreting the oscillogram, scalogram and power spectrum. The heads of both Doryichthys species were prepared for microtomographical scans which were analysed using a 3D imaging software. Additionally, the cranial bones of all three species were examined using a clearing and double-staining method for histological studies. Results. The sound characteristics of the feeding click of the pipefish is species-specific, appearing to be dependent on three bones: the supraoccipital, 1st postcranial plate and 2nd postcranial plate. The sounds are generated when the head of the Dorichthyes pipefishes flexes backward during the feeding strike, as the supraoccipital slides backwards, striking and pushing the 1st postcranial plate against (and striking) the 2nd postcranial plate. In the Syngnathoides pipefish, in the absence of the 1st postcranial plate, the supraoccipital rubs against the 2nd postcranial plate twice as it is pulled backward and released on the return. Cranial morphology and kinesis produce acoustic signals consistent with the bone strikes that produce sharp energy spikes (discrete or merged), or stridulations between bones that produce repeated or multimodal sinusoidal waveforms. Discussion. The variable structure of the sound-producing mechanism explains the unique acoustic signatures of the three species of pipefish. The differences in cranial bone morphology, cranial kinesis and acoustic signatures among pipefishes (and seahorses) could be attributed to independent evolution within the Syngnathidae, which warrants further investigation.
    Matched MeSH terms: Skull
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