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Evaluating the quality of images produced by soft X-ray units

Bradley DA, Wong CS, Ng KH

Appl Radiat Isot, 2000 9 26;53(4-5):691-7.
PMID: 11003508

For broad-beam soft X-ray sources, assessment of the quality of image produced by such units is made complex by the low penetration capabilities of the radiation. In the present study we have tested the utility of several types of test tool, some of which have been fabricated by us, as part of an effort to evaluate several key image defining parameters. These include the film characteristic, focal-spot size, image resolution and detail detectability. The two sources of X-rays used in present studies were the University of Malaya flash X-ray device (UMFX1) and a more conventional soft X-ray tube (Softex, Tokyo), the latter operating at peak accelerating potentials of 20 kVp. We have established, for thin objects, that both systems produce images of comparable quality and, in particular, objects can be resolved down to better than 45 microm.

Matched MeSH terms: Radiography/methods
CHARACTERISATION AND EVALUATION OF AL2O3:C-BASED OPTICALLY STIMULATED LUMINESCENT DOSEMETER SYSTEM FOR DIAGNOSTIC X-RAYS: PERSONAL AND IN VIVO DOSIMETRY

Wong JHD, Bakhsh M, Cheah YY, Jong WL, Khor JS, Ng KH

Radiat Prot Dosimetry, 2019 Dec 31;187(4):451-460.
PMID: 31650160 DOI: 10.1093/rpd/ncz186

This study characterises and evaluates an Al2O3:C-based optically stimulated luminescent dosemeter (OSLD) system, commercially known as the nanoDot™ dosemeter and the InLight® microStar reader, for personal and in vivo dose measurements in diagnostic radiology. The system characteristics, such as dose linearity, reader accuracy, reproducibility, batch homogeneity, energy dependence and signal stability, were explored. The suitability of the nanoDot™ dosemeters was evaluated by measuring the depth dose curve, in vivo dose measurement and image perturbation. The nanoDot™ dosemeters were observed to produce a linear dose with ±2.8% coefficient variation. Significant batch inhomogeneity (8.3%) was observed. A slight energy dependence (±6.1%) was observed between 60 and 140 kVp. The InLight® microStar reader demonstrated good accuracy and a reproducibility of ±2%. The depth dose curve measured using nanoDot™ dosemeters showed slightly lower responses than Monte Carlo simulation results. The total uncertainty for a single dose measurement using this system was 11%, but it could be reduced to 9.2% when energy dependence correction was applied.

Matched MeSH terms: Radiography/methods*
Clinical evaluation of watermarked medical images

Zain JM, Fauzi AM, Aziz AA

Conf Proc IEEE Eng Med Biol Soc, 2007 10 20;2006:5459-62.
PMID: 17946306

Digital watermarking medical images provides security to the images. The purpose of this study was to see whether digitally watermarked images changed clinical diagnoses when assessed by radiologists. We embedded 256 bits watermark to various medical images in the region of non-interest (RONI) and 480K bits in both region of interest (ROI) and RONI. Our results showed that watermarking medical images did not alter clinical diagnoses. In addition, there was no difference in image quality when visually assessed by the medical radiologists. We therefore concluded that digital watermarking medical images were safe in terms of preserving image quality for clinical purposes.

Matched MeSH terms: Radiography/methods*
Fulltext Rapid progression of scoliosis curve in a mature patient with undiagnosed pituitary macroadenoma: A rare case report

Chung WH, Chiu CK, Wei Chan CY, Kwan MK

Acta Orthop Traumatol Turc, 2020 Sep;54(5):561-564.
PMID: 33155569 DOI: 10.5152/j.aott.2020.19144

Growth hormone secreting pituitary tumor or gigantism has not been previously reported to be associated with rapid progression of scoliosis in the literature. However, there are some reports indicating scoliosis can be worsened by growth hormone therapy in children and adolescents. A 19-year-old boy was referred to our institution for the treatment of a right thoracolumbar scoliosis. The Cobb angle had worsened from 29° to 83° over two years' duration. He attained puberty at the age of 13. He had a previous history of slipped upper femoral epiphysis (SUFE), which was operated in 2015, with no clinical features of gigantism. Preoperative assessment was performed. He was diagnosed with growth hormone secreting pituitary macroadenoma by magnetic resonance imaging with a high serum level of insulin-like growth factor-I (IGF-I). Computed tomography (CT) of the pancreas showed a pancreatic endocrine tumor. The patient was later diagnosed with multiple endocrine neoplasia type 1 (MEN 1). He underwent endoscopic endonasal excision of the pituitary mass and distal pancreatectomy. This case indicates that growth hormone secreting pituitary macroadenoma could result in rapid progression of scoliosis.

Matched MeSH terms: Radiography/methods
Surgical Reconstruction of an Open Medial Malleolus Fracture Using a Novel Technique: A Case Report

Kow RY, Yuen JC, Ahmad Alwi AA, Abas MF, Low CL

JBJS Case Connect, 2019 6 25;9(2):e0163.
PMID: 31233428 DOI: 10.2106/JBJS.CC.18.00163

CASE: A 17-year-old male sustained an open fracture of the right medial malleolus (MM) with significant bone and soft tissue loss following a motor-vehicle accident. Following serial wound debridement, his ankle was effectively reconstructed with MM antiglide plate stabilization, iliac autogenous bone graft, and a free radial forearm soft tissue flap.
CONCLUSIONS: Open MM fracture with bone and soft tissue loss is rare. It is feasible to treat this injury with a novel surgical reconstruction technique involving autogenous bicortical iliac bone graft and radial forearm free flap.

Matched MeSH terms: Radiography/methods
The Use of Engineered Bilayered Skin (MyDermTM) in the Management of Massive Skin Defect in Grade III Gustilo-Anderson Open Fracture

Mohamed Haflah NH, Ng MH, Mohd Yunus MH, Naicker AS, Htwe O, Fahmi M, et al.

Int J Low Extrem Wounds, 2017 Sep;16(3):212-216.
PMID: 28862056 DOI: 10.1177/1534734617724974

Open fracture Gustilo-Anderson grade IIIC is associated with higher risk of infection and problems with soft tissue coverage. Various methods have been used for soft tissue coverage in open fractures with large skin defect. We report a case of a patient who had grade IIIC open fracture of the tibia with posterior tibial artery injury. The patient underwent external fixation and reduction. Because of potential compartment syndrome after vascular repair, fasciotomy of the posterior compartment was performed. This wound, however, became infected and because of further debridement, gave rise to a large skin defect. A tissue engineered skin construct, MyDermTM was employed to cover this large defect. Complete wound closure was achieved 35 days postimplantation. The patient then underwent plating of the tibia for nonunion with no adverse effect to the grafted site. The tibia eventually healed 5 months postplating, and the cosmetic appearance of the newly formed skin was satisfactory.

Matched MeSH terms: Radiography/methods
Fulltext Low-dose intrapleural alteplase (without deoxyribonuclease) in complicated parapneumonic effusion: case series and literature reviews

Lai C, Mohammad N, Hassan TM, Abdul Hamid MF

BMJ Case Rep, 2017 Sep 11;2017.
PMID: 28893806 DOI: 10.1136/bcr-2017-221239

This case series reviews two cases of elderly patients who presented with fever, cough and shortness of breath. Clinical examinations and initial chest radiographs confirmed unilateral pleural effusion. Thoracenteses were consistent with exudative pleural effusion. We commenced intravenous antibiotics treating for parapneumonic effusions. The first case showed persistent effusion despite drainage, and the second case had a little aspirate from pleural tapping. Subsequent ultrasound of the thorax showed multiloculated effusions. We made the decisions for intrapleural fibrinolytic therapy using low-dose alteplase 2.5 mg each time, in view of the elderly patient as sacrosanct for risk of bleeding. Furthermore, DNase was not used, as it is not yet available in our setting. Both of our patients had good clinical and radiological outcomes, without the need for surgical interventions.

Matched MeSH terms: Radiography/methods
Fulltext Nasopharyngeal diffuse large B-cells lymphoma causing acute airway obstruction amid COVID-19 crisis: an anaesthetist's nightmare

Yeap TB, Teah MK, Quay YJJ, Wong MTF

BMJ Case Rep, 2021 Jan 28;14(1).
PMID: 33509897 DOI: 10.1136/bcr-2020-241008

Acute stridor is often an airway emergency. We present a valuable experience handling an elderly woman who was initially treated as COVID-19 positive during the pandemic in November 2020. She needed an urgent tracheostomy due to nasopharyngeal (NP) diffuse large B-cell lymphoma causing acute airway obstruction. Fortunately, 1 hour later, her NP swab real-time PCR test result returned as SARS-CoV-2 negative. This interesting article depicts the importance of adequate preparations when handling potentially infectious patients with anticipated difficult airway and the perioperative issues associated with it.

Matched MeSH terms: Radiography/methods
Fulltext A Missed Late Presentation of a Congenital Pulmonary Airway Malformation as a Large Infected Bulla

Lee CY, Osman SS, Noor HM, Isa NSA

Sultan Qaboos Univ Med J, 2018 Nov;18(4):e541-e544.
PMID: 30988978 DOI: 10.18295/squmj.2018.18.04.020

A congenital pulmonary airway malformation (CPAM) is a rare cystic anomaly that may occur during development of the fetal airways. The vast majority of CPAMs are detected in neonates; as such, it is unusual for diagnosis to occur in adulthood. We report a 21-year-old male patient who presented to the emergency department of the Hospital Ampang, Kuala Lumpur, Malaysia, in 2015 with chest pain, breathlessness and tachypnoea. Based on an initial chest X-ray, the patient was misdiagnosed with pneumothorax and underwent urgent chest tube insertion; however, his condition deteriorated over the course of the next three days. Further imaging was suggestive of infected bullae or an undiagnosed CPAM. The patient therefore underwent video-assisted thoracoscopic surgery, during which a large infected bulla was resected. A diagnosis of an infected CPAM was confirmed by histopathological examination. Following the surgery, the patient recovered quickly and no bullae remnants were found at a one-month follow-up.

Matched MeSH terms: Radiography/methods
Is arthroscopic assisted percutaneous screw fixation as good as open reduction and internal fixation for the treatment of displaced intra-articular calcaneal fractures?

Yeap EJ, Rao J, Pan CH, Soelar SA, Younger ASE

Foot Ankle Surg, 2016 Sep;22(3):164-169.
PMID: 27502224 DOI: 10.1016/j.fas.2015.06.008

BACKGROUND: This study compares the outcomes of calcaneal fracture surgery after open reduction internal fixation and plating (ORIF) versus arthroscopic assisted percutaneous screw fixation (APSF).
METHODS: Group I (N=12) underwent ORIF. Group II (N=15) underwent APSF. Anthropometric data, pre and post-operative stay, complications and duration off work were recorded in this retrospective case cohort study. Radiographs were analyzed for Bohler's, Gissane's angle and Sanders' classification. AOFAS Hindfoot and SF 36 scores were collected at final follow-up.
RESULTS: Anthropometric data, Bohler's and Gissane's angles, AOFAS and SF 36 scores were not significantly different. Pre-operative duration was 12.3 days in ORIF and 6.9 days in APSF. Post-operative duration was 7.3 days vs 3.8 days. Duration off work was 6.2 months vs 2.9 months.
CONCLUSION: The APSF group was able to have surgery earlier, go home faster, and return to work earlier. This study was not powered to demonstrate a difference in wound complication rates.

Matched MeSH terms: Radiography/methods