Displaying publications 1241 - 1260 of 1501 in total

Abstract:
Sort:
  1. Ranjbarzadeh R, Jafarzadeh Ghoushchi S, Bendechache M, Amirabadi A, Ab Rahman MN, Baseri Saadi S, et al.
    Biomed Res Int, 2021;2021:5544742.
    PMID: 33954175 DOI: 10.1155/2021/5544742
    The COVID-19 pandemic is a global, national, and local public health concern which has caused a significant outbreak in all countries and regions for both males and females around the world. Automated detection of lung infections and their boundaries from medical images offers a great potential to augment the patient treatment healthcare strategies for tackling COVID-19 and its impacts. Detecting this disease from lung CT scan images is perhaps one of the fastest ways to diagnose patients. However, finding the presence of infected tissues and segment them from CT slices faces numerous challenges, including similar adjacent tissues, vague boundary, and erratic infections. To eliminate these obstacles, we propose a two-route convolutional neural network (CNN) by extracting global and local features for detecting and classifying COVID-19 infection from CT images. Each pixel from the image is classified into the normal and infected tissues. For improving the classification accuracy, we used two different strategies including fuzzy c-means clustering and local directional pattern (LDN) encoding methods to represent the input image differently. This allows us to find more complex pattern from the image. To overcome the overfitting problems due to small samples, an augmentation approach is utilized. The results demonstrated that the proposed framework achieved precision 96%, recall 97%, F score, average surface distance (ASD) of 2.8 ± 0.3 mm, and volume overlap error (VOE) of 5.6 ± 1.2%.
    Matched MeSH terms: Tomography, X-Ray Computed
  2. Loong SP, Afandi AN, Lum CL, Ong CA
    Indian J Otolaryngol Head Neck Surg, 2019 Nov;71(Suppl 3):1692-1694.
    PMID: 31763226 DOI: 10.1007/s12070-015-0945-1
    Solitary extramedullary plasmacytomas are rare, discrete mass of neoplastic monoclonal plasma cells in the soft tissue with no evidence of multiple myeloma. They constitute 3 % of all plasma cell tumors and less than 1 % of head and neck malignancies. A 43 year old lady presented to our clinic with complains of diplopia and headache for 4 weeks. Computed Tomography scan showed a mass lesion in the sphenoid sinus eroding the sinus floor, right wall, basisphenoid and parasellar area. A biopsy of the mass reported as plasmacytoma. Systemic examination revealed no evidence of dissemination of the disease confirming the diagnosis of a solitary extramedullary plasmacytoma. The patient was subjected to 25 fractions of radiotherapy. Here, we report a rare case of solitary extramedullary plasmacytoma of the sphenoid sinus.
    Matched MeSH terms: Tomography, X-Ray Computed
  3. Tan SN, Gendeh HS, Gendeh BS, Ramzisham AR
    Indian J Otolaryngol Head Neck Surg, 2019 Nov;71(Suppl 3):1683-1686.
    PMID: 31763224 DOI: 10.1007/s12070-015-0918-4
    Hemangioma is a disease of head and neck commonly, but its presence in the nasal cavity or sinus is rare. It is a form of benign tumour of vascular origin consisting of predominantly blood vessels. It can be categorized into capillary, cavernous and mixed type in accordance to its histopathology features. Retrospectively, we reviewed five cases of nasal hemangioma presenting at University Kebangsaan Malaysia Medical Center (UKMMC) between September 2007 and May 2015. Information on the patients age, gender, ethnicity, clinical symptoms, imaging findings (if available), treatment modalities were collected retrospectively for analysis. Five patients were analysed. Females were more affected than male with ratio of 4:1. All patients presented with unilateral lobular capillary hemangioma of the nasal cavity with 60 % (3/5) of the lesions on the right side and 40 % (2/5) on the left side. The common symptoms at presentation were epitaxis and nasal obstruction (5/5, 100 %), followed by rhinorrhea (3/5, 60 %) and facial pain (1/5, 20 %). All the patients underwent a surgical excision of the hemangioma. The five patients had no recurrence on subsequent follow ups. Computed tomography of paranasal sinuses can be performed to exclude bony erosions. Endoscopic sinus haemangioma excision provide good visualisation and better outcomes. In conclusion, nasal hemangioma should always be differential diagnosis for nasal lesions and surgical excision is still the preferred first line treatment.
    Matched MeSH terms: Tomography
  4. Liptzin DR, Pickett K, Brinton JT, Agarwal A, Fishman MP, Casey A, et al.
    Ann Am Thorac Soc, 2020 Jun;17(6):724-728.
    PMID: 32109152 DOI: 10.1513/AnnalsATS.201908-617OC
    Rationale: Neuroendocrine cell hyperplasia of infancy (NEHI) is an important form of children's interstitial and diffuse lung disease for which the diagnostic strategy has evolved. The prevalence of comorbidities in NEHI that may influence treatment has not been previously assessed.Objectives: To evaluate a previously unpublished NEHI clinical score for assistance in diagnosis of NEHI and to assess comorbidities in NEHI.Methods: We performed a retrospective chart review of 199 deidentified patients with NEHI from 11 centers. Data were collected in a centralized Research Electronic Data Capture registry and we performed descriptive statistics.Results: The majority of patients with NEHI were male (66%). The sensitivity of the NEHI Clinical Score was 87% (95% confidence interval [CI], 0.82-0.91) for all patients from included centers and 93% (95% CI, 0.86-0.97) for those with complete scores (e.g., no missing data). Findings were similar when we limited the population to the 75 patients diagnosed by lung biopsy (87%; 95% CI, 0.77-0.93). Of those patients evaluated for comorbidities, 51% had gastroesophageal reflux, 35% had aspiration or were at risk for aspiration, and 17% had evidence of immune system abnormalities.Conclusions: The NEHI Clinical Score is a sensitive tool for clinically evaluating NEHI; however, its specificity has not yet been addressed. Clinicians should consider evaluating patients with NEHI for comorbidities, including gastroesophageal reflux, aspiration, and immune system abnormalities, because these can contribute to the child's clinical picture and may influence clinical course and treatment.
    Matched MeSH terms: Tomography, X-Ray Computed
  5. Anuar Zaini A, Feng Tung Y, Ahmad Bahuri NF, Yazid Jalaludin M
    J ASEAN Fed Endocr Soc, 2020;35(1):62-67.
    PMID: 33790495 DOI: 10.15605/jafes.035.01.11
    Introduction: The causes of congenital hypothyroidism (CHT) are thyroid dysgenesis (TD), dyshormonogenesis (TDH) or transient hypothyroidism (TH).

    Methodology: This is a cross-sectional study looking at data over a period of 16 years (2000-2016). Confirmed cases had thyroid scan at the age of 3-years-old and repeated TFT (after 6 weeks off medications). Relevant data was collected retrospectively.

    Results: Forty (60% female) children with CHT were included in the study. Thirty (75%) children presented with high cord TSH. Nine (23%) presented after 2 weeks of life. Majority were diagnosed with TDH (42.5%) with TD and TH of 40% and 17.5% respectively. Median cord TSH of children with TD was significantly higher compared to TDH and TH (p=0.028 and p=0.001 respectively). L-thyroxine doses were not significantly different between TD, TDH and TH at diagnosis or at 3 years.

    Conclusions: TDH is highly prevalent in our population. TD may present after 2 weeks of life. One in five children treated for CHT had TH. Differentiating TD, TDH and TH before initiating treatment remains a challenge in Malaysia. This study provides clinicians practical information needed to understand the possible aetiologies from a patient's clinical presentation, biochemical markers and treatment regime. Reassessing TH cases may be warranted to prevent unnecessary treatment.

    Matched MeSH terms: Tomography, X-Ray Computed
  6. Lim KP, Kok WH, Kamaruddin NA
    J ASEAN Fed Endocr Soc, 2018;33(1):63-68.
    PMID: 33442113 DOI: 10.15605/jafes.033.01.11
    A 69-year-old female complained of intermittent left hip pain for the past 3 years. Biochemical tests revealed normal serum calcium and phosphorus with markedly raised alkaline phosphatase. MRI of the hip revealed extensive marrow signal abnormalities at the left pelvic bone, while CT of the thorax revealed a spiculated lung nodule at the left lower lung lobe. In order to diagnose either primary, metastatic bone tumour or Paget's disease of the bone (PDB), an open biopsy of the left iliac bone was performed. The histopathology of bone biopsy of the left iliac bone was consistent with PDB. A CT guided biopsy of the lung mass done later revealed adenocarcinoma of the lung. She had 18F-FDG PETCECT Scan for staging evaluation and result was suggestive of new bony metastases. Patient was started on IV Zoledronic acid for treatment of the PDB. In view of the stage 4 lung adenocarcinoma with bony metastases, patient was scheduled for palliative chemotherapy.
    Matched MeSH terms: Tomography, X-Ray Computed
  7. Mohd-Tahir F, Siti-Raihan I, Wan Hazabbah WH
    Case Rep Ophthalmol Med, 2013;2013:158961.
    PMID: 23533876 DOI: 10.1155/2013/158961
    Aim. To report a rare case of arteriovenous malformation in temporal lobe presenting as contralateral orbital symptoms mimicking carotid-cavernous fistula. Method. Interventional case report. Results. A 31-year-old Malay gentleman presented with 2-month history of painful progressive exophthalmos of his left eye associated with recurrent headache, diplopia, and reduced vision. Ocular examination revealed congestive nonpulsating 7 mm exophthalmos of the left eye with no restriction of movements in all direction. There was diplopia in left lateral gaze. Left IOP was elevated at 29 mmHg. Left eye retinal vessels were slightly dilated and tortuous. CT scan was performed and showed right temporal arteriovenous malformation with a nidus of 3.8 cm × 2.5 cm with right middle cerebral artery as feeding artery. There was dilated left superior ophthalmic vein of 0.9 mm in diameter with enlarged left cavernous sinus. MRA and carotid angiogram confirmed right temporal arteriovenous malformation with no carotid-cavernous fistula. Most of the intracranial drainage was via left cavernous sinus. His signs and symptoms dramatically improved following successful embolisation, completely resolved after one year. Conclusion. Intracranial arteriovenous malformation is rarely presented with primary ocular presentation. Early intervention would salvage the eyes and prevent patients from more disaster morbidity or fatality commonly due to intracranial haemorrhage.
    Matched MeSH terms: Tomography, X-Ray Computed
  8. Tan YY, Tan K
    Clin Med (Lond), 2019 Nov;19(6):511-513.
    PMID: 31732595 DOI: 10.7861/clinmed.2019-0247
    Hypertensive encephalopathy (HE) is a subset of posterior reversible encephalopathy syndrome. It typically involves the posterior supratentorial structures, but variations do occur. However, isolated brainstem involvement in HE is rare, with a few cases reported in the literature. Herein, we report a case of acute hypertensive brainstem encephalopathy in which the patient had mild symptoms with very high blood pressure and normal neurological examination. The computed tomography of the brain showed diffuse hypodensity at brainstem. The patient's symptoms improved drastically after hypertension had been controlled. Marked clinical-radiologic dissociation in this particular case was highly suggestive of hypertensive brainstem encephalopathy. Prompt recognition of the condition and aggressive treatment of hypertension in such patients is crucial to relieve oedema and to prevent life-threatening progression. Nevertheless, there is still a lack of awareness among physicians and radiologists regarding this rare clinical entity.
    Matched MeSH terms: Tomography, X-Ray Computed
  9. Lim D, Parumo R, Chai MB, Shanmuganathan J
    J Oral Implantol, 2017 Jun;43(3):228-231.
    PMID: 27996585 DOI: 10.1563/aaid-joi-D-16-00172
    Displacement of dental implants into the maxillary sinus is a rare complication. This article presents a case of displaced dental implant into maxillary sinus. Retrieval of the dental implant from left maxillary sinus was performed via endoscopic sinus surgery. This case highlighted a delayed referral of a 53-year-old male by a general dental practitioner for management of a dislodged dental implant into the left maxillary antrum. The implant was dislodged during placement of a healing abutment 4 months after implant insertion to replace missing 25. Cone beam computerized tomography revealed the displaced implant was located at the ostium of the left nose. A sudden change in sinonasal pressure when the patient took a deep breath during the procedure may have created a negative pressure and suction effect causing the implant to be dislodged and embedded at the ostium. In view of its position, a referral to an otorhinolaryngologist was made for endoscopic removal of the displaced implant. This case also highlighted the need for inter disciplinary cooperation in the management of such a complication for the best interest of the patients.
    Matched MeSH terms: Cone-Beam Computed Tomography
  10. Ardakani AA, Kanafi AR, Acharya UR, Khadem N, Mohammadi A
    Comput Biol Med, 2020 Jun;121:103795.
    PMID: 32568676 DOI: 10.1016/j.compbiomed.2020.103795
    Fast diagnostic methods can control and prevent the spread of pandemic diseases like coronavirus disease 2019 (COVID-19) and assist physicians to better manage patients in high workload conditions. Although a laboratory test is the current routine diagnostic tool, it is time-consuming, imposing a high cost and requiring a well-equipped laboratory for analysis. Computed tomography (CT) has thus far become a fast method to diagnose patients with COVID-19. However, the performance of radiologists in diagnosis of COVID-19 was moderate. Accordingly, additional investigations are needed to improve the performance in diagnosing COVID-19. In this study is suggested a rapid and valid method for COVID-19 diagnosis using an artificial intelligence technique based. 1020 CT slices from 108 patients with laboratory proven COVID-19 (the COVID-19 group) and 86 patients with other atypical and viral pneumonia diseases (the non-COVID-19 group) were included. Ten well-known convolutional neural networks were used to distinguish infection of COVID-19 from non-COVID-19 groups: AlexNet, VGG-16, VGG-19, SqueezeNet, GoogleNet, MobileNet-V2, ResNet-18, ResNet-50, ResNet-101, and Xception. Among all networks, the best performance was achieved by ResNet-101 and Xception. ResNet-101 could distinguish COVID-19 from non-COVID-19 cases with an AUC of 0.994 (sensitivity, 100%; specificity, 99.02%; accuracy, 99.51%). Xception achieved an AUC of 0.994 (sensitivity, 98.04%; specificity, 100%; accuracy, 99.02%). However, the performance of the radiologist was moderate with an AUC of 0.873 (sensitivity, 89.21%; specificity, 83.33%; accuracy, 86.27%). ResNet-101 can be considered as a high sensitivity model to characterize and diagnose COVID-19 infections, and can be used as an adjuvant tool in radiology departments.
    Matched MeSH terms: Tomography, X-Ray Computed
  11. Jeng TC, Haspani MS, Adnan JS, Naing NN
    Malays J Med Sci, 2008 Oct;15(4):56-67.
    PMID: 22589639
    A repeat Computer Tomographic (CT) brain after 24-48 hours from the 1(st) scanning is usually practiced in most hospitals in South East Asia where intracranial pressure monitoring (ICP) is routinely not done. This interval for repeat CT would be shortened if there was a deterioration in Glasgow Coma Scale (GCS). Most of the time the prognosis of any intervention may be too late especially in hospitals with high patient-to-doctor ratio causing high mortality and morbidity. The purpose of this study was to determine the important predictors for early detection of Delayed Traumatic Intracranial Haemorrhage (DTICH) and Progressive Traumatic Brain Injury (PTBI) before deterioration of GCS occurred, as well as the most ideal timing of repeated CT brain for patients admitted in Malaysian hospitals. A total of 81 patients were included in this study over a period of six months. The CT scan brain was studied by comparing the first and second CT brain to diagnose the presence of DTICH/PTBI. The predictors tested were categorised into patient factors, CT brain findings and laboratory investigations. The mean age was 33.1 ± 15.7 years with a male preponderance of 6.36:1. Among them, 81.5% were patients from road traffic accidents with Glasgow Coma Scale ranging from 4 - 15 (median of 12) upon admission. The mean time interval delay between trauma and first CT brain was 179.8 ± 121.3 minutes for the PTBI group. The DTICH group, 9.9% of the patients were found to have new intracranial clots. Significant predictors detected were different referral hospitals (p=0.02), total GCS status (p=0.026), motor component of GCS (p=0.043), haemoglobin level (p<0.001), platelet count (p=0.011) and time interval between trauma and first CT brain (p=0.022). In the PTBI group, 42.0% of the patients were found to have new changes (new clot occurrence, old clot expansion and oedema) in the repeat CT brain. Univariate statistical analysis revealed that age (p=0.03), race (p=0.035), types of admission (p=0.024), GCS status (p=0.02), pupillary changes (p=0.014), number of intracranial lesion (p=0.004), haemoglobin level (p=0.038), prothrombin time (p=0.016) as the best predictors of early detection of changes. Multiple logistics regression analysis indicated that age, severity, GCS status (motor component) and GCS during admission were significantly associated with second CT scan with changes. This study showed that 9.9% of the total patients seen in the period of study had DTICH and 42% had PTBI. In the early period after traumatic head injury, the initial CT brain did not reveal the full extent of haemorrhagic injury and associated cerebral oedema. Different referral hospitals of different trauma level, GCS status, motor component of the GCS, haemoglobin level, platelet count and time interval between trauma and the first CT brain were the significant predictors for DTICH. Whereas the key determinants of PTBI were age, race, types of admission, GCS status, pupillary changes, number of intracranial bleed, haemoglobin level, prothrombin time and of course time interval between trauma and first CT brain. Any patients who had traumatic head injury in hospitals with no protocol of repeat CT scan or intracranial pressure monitoring especially in developing countries are advised to have to repeat CT brain at the appropriate quickest time .
    Matched MeSH terms: Tomography, X-Ray Computed
  12. Hoang T, Kieu H, Nguyen V, Tran T, Ngee T, Duong H
    PMID: 39230213
    BACKGROUND: To evaluate the treatment outcomes of lateral interbody bone graft surgery and posterior percutaneous screws for lumbar spinal stenosis Methods: This is a cross-sectional descriptive study. There were 27 patients with 30 segments of surgery diagnosed with lumbar spinal stenosis that were surgically treated with the XLIF method. Clinical outcomes measured included VAS scores for lower back pain and leg pain, ODI, and JOA scores. Magnetic resonance imaging of the lumbar spine after surgery was used to evaluate indirect decompression. X-ray or CT scan to evaluate bone fusion after 6 months of surgery. Differences were determined by independent T-test.

    RESULTS: There were 27 patients with 30 segments of surgery. They were 12 males and 15 females with an average age of 58.81±8.1. There was significant improvement in VAS for lower back pain from 7.11±1.31 to 3.67±1.3, VAS for leg pain from 6.81±2.19 to 1.59±1.89, ODI from 26.41±8.95 to 13.69±8.34, and JOA score from 7.63±2.87 to 13.5±1.73. A-P diameter increased 134%, lateral diameter increased 120%, lateral recess depth increased 166%, disc height increased 126%, foraminal height increased 124%, spinal canal area increased 30%. The p-values were all <0.001. The average hospital stay was 6.79±3.01 days. Complications included 1 pedicle screw malformation, 1 ALL avulsion fracture, 1 abdominal herniation, 1 venous damage, 1 failure.

    CONCLUSION: XLIF surgery presents a favorable option for patients with lumbar spinal stenosis. This is a minimally invasive surgical method that reduces pain, reduces bleeding, and is effective in indirectly decompressing the spinal canal both clinal and imaging.

    Matched MeSH terms: Tomography, X-Ray Computed
  13. Tan JL, Nordin S, Besari AM
    Malays J Med Sci, 2017 Oct;24(5):119-123.
    PMID: 29386980 MyJurnal DOI: 10.21315/mjms2017.24.5.14
    Introduction: Tuberculosis is the second leading cause of death under the category of infectious diseases, after the human immunodeficiency virus (HIV). Tuberculous meningitis (TBM) constitutes about 5% of all extrapulmonary disease worldwide. This report describes a case of Tuberculous meningitis with rare presentation in a 28-year-old woman, who was treated based on a collection of her social background, clinical findings and Multiplex PCR of tuberculosis.

    Case presentation: A 28-year-old Malay woman with no significant medical history presented to HUSM with one month history of on and off fever, two weeks history of generalised limbs weakness and one week history of dysphagia. She was reported to have experienced visual hallucination and significant weight loss. Her laboratory result is significant for leukocytosis, elevated ESR and hypernatremia. Non-enhanced and contrast CT scan of the brain showed severe bilateral frontal cerebral atrophy. Cerebral spinal fluid (CSF) for multiplex PCR for Mycobacterium tuberculosis complex was positive. She was promptly started on anti-TB regime combined with dexamethasone. Subsequent follow-up showed significant improvement.

    Conclusion: This is a rare clinical manifestation of Tuberculous meningitis that demonstrates the importance of recognising and initiating the treatment early to reduce disabilities and improve clinical outcome.

    Matched MeSH terms: Tomography, X-Ray Computed
  14. Kaur G, Mutum SS
    Malays J Med Sci, 2001 Jan;8(1):69-72.
    PMID: 22973160
    Hepatoblastoma is the most common primary liver tumour of childhood. This is a case report of a one-year-old boy who presented with a one-month history of progressive abdominal distension and weight loss. He was cachexic, anaemic, had gross hepatomegaly and ascites. He had been born prematurely with a birth weight of 1.23 kg, and his developmental milestones were delayed. Ultrasound and CT scan demonstrated a large solid tumour in the left lobe of the liver with a smaller superficial nodule in the right lobe. Serum alpha fetoprotein was significantly raised. A left lobe hepatectomy and complete excision of the right sided nodule was performed. There was no evidence of metastatic disease. Histopathological examination confirmed hepatoblastoma of the fetal type. The patient developed features of intestinal obstruction a few days after surgery and he succumbed ten days after re-laparotomy. The clinical presentation and investigation results in this case are characteristic. Recent reports have suggested a strong relationship between very low birth weight (< 1500gm)/prematurity and hepatoblastoma as is present in this case. Surgery is the mainstay of therapy in hepatoblastoma. A brief review of the literature on this tumour is presented.
    Matched MeSH terms: Tomography, X-Ray Computed
  15. Woolley AK, Hedger NA, Veettil RP
    Acute Med, 2013;12(2):107-10.
    PMID: 23732136
    Pyrexia of unknown origin (PUO) is a frequent presentation to the Acute Medical Unit, and is a source of significant morbidity, both the psychological burden of an uncertain diagnosis and prognosis and untreated complications of the underlying pathology. We present a problem based review of the management of PUO, illustrated by a patient who recently presented to our unit with fever and systemic malaise after returning from abroad and in whom no cause could be found for more than two months. We describe a structured approach making use of complex modern techniques such as Positron Emission Tomography-Computed Tomography (PET-CT) which ultimately provided the diagnosis for our patient.
    Matched MeSH terms: Tomography, X-Ray Computed; Positron-Emission Tomography
  16. Mazita A, Zabri M, Aneeza WH, Asma A, Saim L
    J Laryngol Otol, 2011 Nov;125(11):1116-20.
    PMID: 21846418 DOI: 10.1017/S0022215111002052
    To review cases of congenital external auditory canal anomaly with cholesteatoma, documenting clinical presentation, cholesteatoma site and extent, complications, and surgery.
    Matched MeSH terms: Tomography, X-Ray Computed/methods
  17. Lim SY, Mason WP, Young NP, Chen R, Bower JH, McKeon A, et al.
    Arch. Neurol., 2009 Oct;66(10):1285-7.
    PMID: 19822786 DOI: 10.1001/archneurol.2009.203
    OBJECTIVE:
    To describe and provide audiovisual documentation of a syndrome of polymyoclonus, laryngospasm, and cerebellar ataxia associated with adenocarcinoma and multiple neural cation channel autoantibodies.

    DESIGN:
    Case report with video.

    SETTING:
    University hospitals. Patient A 69-year-old woman presented with subacute onset of whole-body tremulousness and laryngospasm attributed to gastroesophageal reflux.

    RESULTS:
    Further evaluation revealed polymyoclonus, cerebellar ataxia, and laryngospasm suspicious of an underlying malignant neoplasm. Surface electromyography of multiple limb muscles confirmed the presence of polymyoclonus. The patient was seropositive for P/Q-type voltage-gated calcium channel antibody; subsequently, whole-body fluorine 18 fluorodeoxyglucose positron emission tomography and cervical lymph node biopsy revealed widespread metastatic adenocarcinoma. Follow-up serologic evaluation revealed calcium channel antibodies (P/Q type and N type) and potassium channel antibody.

    CONCLUSIONS:
    We highlight the importance of recognizing polymyoclonus. To our knowledge, this is also the first description of a syndrome of polymyoclonus, laryngospasm, and ataxia associated with adenocarcinoma and these cation channel antibodies.
    Matched MeSH terms: Tomography, X-Ray Computed; Positron-Emission Tomography
  18. Roselt P, Cullinane C, Noonan W, Elsaidi H, Eu P, Wiebe LI
    Molecules, 2020 Dec 03;25(23).
    PMID: 33287202 DOI: 10.3390/molecules25235700
    Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E's biodistributions and pharmacokinetics via non-invasive temporal imaging. (R)-6-(3-[18F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([18F]F-γ-T-3) was prepared for this purpose. [18F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di-O-tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [18F]fluoride in DMF/K222. Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [18F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [18F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [18F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues.
    Matched MeSH terms: Positron-Emission Tomography/methods
  19. Lim TH, Lai TYY, Takahashi K, Wong TY, Chen LJ, Ruamviboonsuk P, et al.
    JAMA Ophthalmol, 2020 09 01;138(9):935-942.
    PMID: 32672800 DOI: 10.1001/jamaophthalmol.2020.2443
    Importance: The 2-year efficacy and safety of combination therapy of ranibizumab administered together with verteporfin photodynamic therapy (vPDT) compared with ranibizumab monotherapy in participants with polypoidal choroidal vasculopathy (PCV) are unclear.

    Objective: To compare treatment outcomes of ranibizumab, 0.5 mg, plus prompt vPDT combination therapy with ranibizumab, 0.5 mg, monotherapy in participants with PCV for 24 months.

    Design, Setting, and Participants: This 24-month, phase IV, double-masked, multicenter, randomized clinical trial (EVEREST II) was conducted among Asian participants from August 7, 2013, to March 2, 2017, with symptomatic macular PCV confirmed using indocyanine green angiography.

    Interventions: Participants (N = 322) were randomized 1:1 to ranibizumab, 0.5 mg, plus vPDT (combination therapy group; n = 168) or ranibizumab, 0.5 mg, plus sham PDT (monotherapy group; n = 154). All participants received 3 consecutive monthly ranibizumab injections, followed by a pro re nata regimen. Participants also received vPDT (combination group) or sham PDT (monotherapy group) on day 1, followed by a pro re nata regimen based on the presence of active polypoidal lesions.

    Main Outcomes and Measures: Evaluation of combination therapy vs monotherapy at 24 months in key clinical outcomes, treatment exposure, and safety. Polypoidal lesion regression was defined as the absence of indocyanine green hyperfluorescence of polypoidal lesions.

    Results: Among 322 participants (mean [SD] age, 68.1 [8.8] years; 225 [69.9%] male), the adjusted mean best-corrected visual acuity (BCVA) gains at month 24 were 9.6 letters in the combination therapy group and 5.5 letters in the monotherapy group (mean difference, 4.1 letters; 95% CI, 1.0-7.2 letters; P = .005), demonstrating that combination therapy was superior to monotherapy by the BCVA change from baseline to month 24. Combination therapy was superior to monotherapy in terms of complete polypoidal lesion regression at month 24 (81 of 143 [56.6%] vs 23 of 86 [26.7%] participants; P 

    Matched MeSH terms: Tomography, Optical Coherence/methods
  20. Tenekecioglu E, Serruys PW, Onuma Y, Costa R, Chamié D, Sotomi Y, et al.
    JACC Cardiovasc Interv, 2017 06 12;10(11):1115-1130.
    PMID: 28527768 DOI: 10.1016/j.jcin.2017.03.015
    OBJECTIVES: The primary objective of this study was to evaluate the safety and effectiveness of the Mirage (Manli Cardiology, Singapore) bioresorbable microfiber sirolimus-eluting scaffold compared with the Absorb (Abbott Vascular, Santa Clara, California) bioresorbable vascular scaffold in the treatment of stenotic target lesions located in native coronary arteries, ranging from ≥2.25 to ≤4.0 mm in diameter. Secondary objectives were to establish the medium-term safety, effectiveness, and performance of the Mirage device.

    BACKGROUND: The current generation of bioresorbable scaffolds has several limitations, such as thick square struts with large footprints that preclude their deep embedment into the vessel wall, resulting in protrusion into the lumen with microdisturbance of flow. The Mirage sirolimus-eluting bioresorbable microfiber scaffold is designed to address these concerns.

    METHODS: In this prospective, single-blind trial, 60 patients were randomly allocated in a 1:1 ratio to treatment with a Mirage sirolimus-eluting bioresorbable microfiber scaffold or an Absorb bioresorbable vascular scaffold. The clinical endpoints were assessed at 30 days and at 6 and 12 months. In-device angiographic late loss at 12 months was quantified. Secondary optical coherence tomographic endpoints were assessed post-scaffold implantation at 6 and 12 months.

    RESULTS: Median angiographic post-procedural in-scaffold minimal luminal diameters of the Mirage and Absorb devices were 2.38 mm (interquartile range [IQR]: 2.06 to 2.62 mm) and 2.55 mm (IQR: 2.26 to 2.71 mm), respectively; the effect size (d) was -0.29. At 12 months, median angiographic in-scaffold minimal luminal diameters of the Mirage and Absorb devices were not statistically different (1.90 mm [IQR: 1.57 to 2.31 mm] vs. 2.29 mm [IQR: 1.74 to 2.51 mm], d = -0.36). At 12-month follow-up, median in-scaffold late luminal loss with the Mirage and Absorb devices was 0.37 mm (IQR: 0.08 to 0.72 mm) and 0.23 mm (IQR: 0.15 to 0.37 mm), respectively (d = 0.20). On optical coherence tomography, post-procedural diameter stenosis with the Mirage was 11.2 ± 7.1%, which increased to 27.4 ± 12.4% at 6 months and remained stable (31.8 ± 12.9%) at 1 year, whereas the post-procedural optical coherence tomographic diameter stenosis with the Absorb was 8.4 ± 6.6%, which increased to 16.6 ± 8.9% and remained stable (21.2 ± 9.9%) at 1-year follow-up (Mirage vs. Absorb: dpost-procedure = 0.41, d6 months = 1.00, d12 months = 0.92). Angiographic median in-scaffold diameter stenosis was significantly different between study groups at 12 months (28.6% [IQR: 21.0% to 40.7%] for the Mirage, 18.2% [IQR: 13.1% to 31.6%] for the Absorb, d = 0.39). Device- and patient-oriented composite endpoints were comparable between the 2 study groups.

    CONCLUSIONS: At 12 months, angiographic in-scaffold late loss was not statistically different between the Mirage and Absorb devices, although diameter stenosis on angiography and on optical coherence tomography was significantly higher with the Mirage than with the Absorb. The technique of implantation was suboptimal for both devices, and future trials should incorporate optical coherence tomographic guidance to allow optimal implantation and appropriate assessment of the new technology, considering the novel mechanical properties of the Mirage.

    Matched MeSH terms: Tomography, Optical Coherence*
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links