MyMedR

Inter-observer Variability Analysis of Automatic Lung Delineation in Normal and Disease Patients

Saba L, Than JC, Noor NM, Rijal OM, Kassim RM, Yunus A, et al.

J Med Syst, 2016 Jun;40(6):142.

PMID: 27114353 DOI: 10.1007/s10916-016-0504-7

Human interaction has become almost mandatory for an automated medical system wishing to be accepted by clinical regulatory agencies such as Food and Drug Administration. Since this interaction causes variability in the gathered data, the inter-observer and intra-observer variability must be analyzed in order to validate the accuracy of the system. This study focuses on the variability from different observers that interact with an automated lung delineation system that relies on human interaction in the form of delineation of the lung borders. The database consists of High Resolution Computed Tomography (HRCT): 15 normal and 81 diseased patients' images taken retrospectively at five levels per patient. Three observers manually delineated the lungs borders independently and using software called ImgTracer™ (AtheroPoint™, Roseville, CA, USA) to delineate the lung boundaries in all five levels of 3-D lung volume. The three observers consisted of Observer-1: lesser experienced novice tracer who is a resident in radiology under the guidance of radiologist, whereas Observer-2 and Observer-3 are lung image scientists trained by lung radiologist and biomedical imaging scientist and experts. The inter-observer variability can be shown by comparing each observer's tracings to the automated delineation and also by comparing each manual tracing of the observers with one another. The normality of the tracings was tested using D'Agostino-Pearson test and all observers tracings showed a normal P-value higher than 0.05. The analysis of variance (ANOVA) test between three observers and automated showed a P-value higher than 0.89 and 0.81 for the right lung (RL) and left lung (LL), respectively. The performance of the automated system was evaluated using Dice Similarity Coefficient (DSC), Jaccard Index (JI) and Hausdorff (HD) Distance measures. Although, Observer-1 has lesser experience compared to Obsever-2 and Obsever-3, the Observer Deterioration Factor (ODF) shows that Observer-1 has less than 10% difference compared to the other two, which is under acceptable range as per our analysis. To compare between observers, this study used regression plots, Bland-Altman plots, two tailed T-test, Mann-Whiney, Chi-Squared tests which showed the following P-values for RL and LL: (i) Observer-1 and Observer-3 were: 0.55, 0.48, 0.29 for RL and 0.55, 0.59, 0.29 for LL; (ii) Observer-1 and Observer-2 were: 0.57, 0.50, 0.29 for RL and 0.54, 0.59, 0.29 for LL; (iii) Observer-2 and Observer-3 were: 0.98, 0.99, 0.29 for RL and 0.99, 0.99, 0.29 for LL. Further, CC and R-squared coefficients were computed between observers which came out to be 0.9 for RL and LL. All three observers however manage to show the feature that diseased lungs are smaller than normal lungs in terms of area.

Matched MeSH terms: Tomography, X-Ray Computed/methods*

Contrast media induced transient cortical blindness

Balasingam S, Azman RR, Nazri M

QJM, 2016 Feb;109(2):121-2.

PMID: 26101228 DOI: 10.1093/qjmed/hcv121

Matched MeSH terms: Tomography, X-Ray Computed/methods

Dislocation of cervico-thoracic spine with no neurological deficit--a case report

Saw A, Sengupta S

Injury, 2001 Jun;32(5):430-2.

PMID: 11382432

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Mesenchymal chondrosarcoma of maxilla in paediatric patient

Choo CS, Wan Abdul Rahman WF, Jaafar H, Ramli RR

BMJ Case Rep, 2019 Mar 09;12(3).

PMID: 30852518 DOI: 10.1136/bcr-2018-228969

Chondrosarcoma (CS) is a malignant tumour of long and flat bone characterised by the formation of cartilage. Mesenchymal chondrosarcoma (MCS) is a rare subtype of CS that is more aggressive and may lead to erroneous diagnosis in a limited biopsy. The diagnosis is mainly based on the histopathological appearance of biphasic pattern of undifferentiated small round cells separated by islands of well-differentiated hyaline cartilage. We report a case of 13-year-old boy who initially presented with gum swelling and the biopsy result suggested a benign fibrous lesion. Following an extensive lesion shown in radiologic findings, the tumour excision was done and finally was diagnosed as an MCS of the maxilla. The patient was given postoperative chemotherapy (EURO-EWING 99 regimen), and now on regular follow-up for monitoring of local recurrence or tumour metastasis.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Superior mesenteric artery syndrome: A rare complication of scoliosis corrective surgery

Chung WH, Anuar AA, Lee KJ, Hasan MS, Chiu CK, Chan CYW, et al.

J Orthop Surg (Hong Kong), 2020 9 11;28(3):2309499020945014.

PMID: 32909907 DOI: 10.1177/2309499020945014

Superior mesenteric artery (SMA) syndrome is a rare but serious complication following scoliosis surgery. Early diagnosis and management are key factors for successful conservative treatment to avoid the need for emergency laparotomies which causes higher morbidity or even mortality. We report two adolescent idiopathic scoliosis patients with Cobb angle of 49° and 132°, respectively, and low body mass index who presented with SMA syndrome following posterior spinal fusion from T2 to L3 and were treated successfully with conservative management. Abdominal radiographs showed distended gastric shadow. Computed tomography angiography of the abdomen showed decreased aortomesenteric angle and SMA-aorta distance. Both patients were treated successfully with conservative treatment which included three principles: gastric decompression with nasogastric tube, correction of electrolytes imbalance, and nutritional support with low volume, high calorie nutritional supplement. Both patients were started with small but frequent meals. Surgeries were not required in both cases. Early diagnosis and management are the key factors to successful treatment in SMA syndrome. Patients with SMA can be treated successfully with conservative treatment comprising of nasogastric decompression, electrolyte correction, and nutritional support with small but frequent meals.

Matched MeSH terms: Tomography, X-Ray Computed/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: Tomography, X-Ray Computed/methods*

Does the Severity of the Curve in Lenke 1 and 2 Adolescent Idiopathic Scoliosis Patients Affect the Distance and Position of the Aorta From Vertebra?

Chiu CK, Lee KJ, Chung WH, Chandren JR, Chan CYW, Kwan MK

Spine (Phila Pa 1976), 2019 Jun 01;44(11):785-792.

PMID: 30475346 DOI: 10.1097/BRS.0000000000002945

STUDY DESIGN: Retrospective study of a prospectively-collected data.

OBJECTIVE: To determine whether the severity of the curve magnitude in Lenke 1 and 2 Adolescent Idiopathic Scoliosis (AIS) patients affects the distance and position of the aorta from the vertebra.

SUMMARY OF BACKGROUND DATA: There were studies that looked into the position of the aorta in scoliotic patients but none of them documented the change in distance of the aorta to the vertebra in relation to the magnitude of the scoliosis.

METHODS: Patients with Lenke 1 and 2 AIS who underwent posterior spinal fusion using pedicle screw construct and had a preoperative computed tomography (CT) scan performed were recruited. The radiological parameters measured on preoperative CT scan were: Aortic-Vertebral Distance (AVD), Entry-Aortic Distance (EAD), Aortic-Vertebral angle (AVA), Pedicle Aorta angle/Aortic Alpha angle (α angle), and Aortic Beta angle (β angle).

RESULTS: Thirty-nine patients were recruited. Significant moderate to strong positive correlation was found between AVD and Cobb angle from T8 to T12 vertebrae (r = 0.360 to 0.666). The EAD was generally small in the thoracic region (T4-T10) with mean EAD of less than 30 mm. Among all apical vertebrae, the mean AVD was 5.9 ± 2.2 mm with significant moderate-strong positive correlation to Cobb angle (r = 0.580). The mean α angle was 37.7 ± 8.7° with significant weak positive correlation with Cobb angle (r = 0.325).

CONCLUSION: The larger the scoliotic curve, the aorta was located further away from the apical vertebral wall. The aorta has less risk of injury from the left lateral pedicle screw breach in larger scoliotic curve at the apical region. The distance from the pedicle screw entry point to the wall of the aorta was generally small (less than 30 mm) in the thoracic region (T4-T10).

LEVEL OF EVIDENCE: 4.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Emphysematous gastritis after metastatic malignant melanoma: a radiological surprise

Ng CY, Hayati F, Nadarajan C

BMJ Case Rep, 2020 Sep 09;13(9).

PMID: 32912885 DOI: 10.1136/bcr-2020-235174

Malignant melanoma is cancer of the skin which commonly metastasises to the stomach. There have been no reported cases of emphysematous gastritis secondary to metastasis of malignant melanomas, to date. However, a 61-year-old woman with metastatic malignant melanoma of the left great toe presented to us with symptoms of severe left hypochondrium pain associated with high-grade fever, gross abdominal distension and recurrent vomiting. Two months earlier, metastasis was observed to have spread to the stomach and inguinal lymph nodes. At this stage, the patient opted for traditional medication instead of definitive surgery and chemotherapy. Radiological imaging revealed an emphysematous change to the stomach which was radiologically consistent with gastric malignant melanoma. Unfortunately, the patient succumbed to this rare condition.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Three-Dimensional Computed Tomography Analysis of the Posterior Tibial Slope in 100 Knees

Ho JPY, Merican AM, Hashim MS, Abbas AA, Chan CK, Mohamad JA

J Arthroplasty, 2017 10;32(10):3176-3183.

PMID: 28579444 DOI: 10.1016/j.arth.2017.04.060

BACKGROUND: The posterior tibial slope (PTS) is an important consideration in knee arthroplasty. However, there is still no consensus for the optimal slope. The objectives of this study were (1) to reliably determine the native PTS in this population using 3-dimensional computed tomography scans and (2) to determine the normal reference range for PTS in this population.

METHODS: One hundred computed tomography scans of disease-free knees were analyzed. A 3-dimensional reconstructed image of the tibia was generated and aligned to its anatomic axis in the coronal and sagittal planes. The tibia was then rotationally aligned to the tibial plateau (tibial centroid axis) and PTS was measured from best-fit planes on the surface of the proximal tibia and individually for the medial and lateral plateaus. This was then repeated with the tibia rotationally aligned to the ankle (transmalleolar axis).

RESULTS: When rotationally aligned to the tibial plateau, the mean PTS, medial PTS, and lateral PTS were 11.2° ± 3.0 (range, 4.7°-17.7°), 11.3° ± 3.2 (range, 2.7°-19.7°), and 10.9° ± 3.7 (range, 3.5°-19.4°), respectively. When rotationally aligned to the ankle, the mean PTS, medial PTS, and lateral PTS were 11.4° ± 3.0 (range, 5.3°-19.3°), 13.9° ± 3.7 (range, 3.1°-24.4°), and 9.7° ± 3.6 (range, 0.8°-17.7°), respectively.

CONCLUSION: The PTS in the normal Asian knee is on average 11° (mean) with a reference range of 5°-17° (mean ± 2 standard deviation). This has implications to surgery and implant design.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Imaging features of toxic megacolon

Ong SCL, Mohaidin N

BMJ Case Rep, 2018 Sep 30;2018.

PMID: 30275028 DOI: 10.1136/bcr-2018-227121

Matched MeSH terms: Tomography, X-Ray Computed/methods*

Fulltext A woman with fever and cough: coronavirus disease 2019

Lu YQ

Intern Emerg Med, 2020 Nov;15(8):1553-1554.

PMID: 32232784 DOI: 10.1007/s11739-020-02321-3

Matched MeSH terms: Tomography, X-Ray Computed/methods

Retained Endoscope: An Unexpected but Serious Complication of Hemospray®

Yii RSL, Chuah KH, Poh KS, Lau PC, Ng KL, Ho SH, et al.

Dig Dis Sci, 2022 01;67(1):344-347.

PMID: 33491164 DOI: 10.1007/s10620-021-06835-4

Matched MeSH terms: Tomography, X-Ray Computed/methods

Adult primary medullary carcinoma: an unusual cause of pain from intussusception

Chuah YY, Lee YY, Shih CA

Br J Hosp Med (Lond), 2017 Aug 02;78(8):474.

PMID: 28783396 DOI: 10.12968/hmed.2017.78.8.474

Matched MeSH terms: Tomography, X-Ray Computed/methods

Robotic excision of large retroperitoneal Schwannoma (with video)

Ragu R, Blanchard C, Meurette G

J Visc Surg, 2017 09;154(4):297-299.

PMID: 28802708 DOI: 10.1016/j.jviscsurg.2017.05.003

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Splenic amyloidosis: a rare cause of spontaneous splenic rupture

Chan RS, Abdul Aziz YF, Chandran P, Ng EK

Singapore Med J, 2011 Nov;52(11):e232-5.

PMID: 22173263

A 62 year-old woman who presented with an atraumatic acute abdomen was discovered to have haemoperitoneum with splenic rupture on urgent computed tomography and was immediately referred for life-saving emergency splenectomy. Histopathological examination revealed secondary splenic amyloidosis. The patient was later found to be suffering from infective endocarditis secondary to her permanent cardiac pacemaker. This report describes a patient who could have suffered from a long-standing infected vegetation on a permanent cardiac pacemaker, which led to splenic amyloidosis and spontaneous splenic rupture.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Frontal mucocoele secondary to nasal polyposis: an unusual complication

Chew YK, Noorizan Y, Khir A, Brito-Mutunayagam S, Prepageran N

Singapore Med J, 2009 Nov;50(11):e374-5.

PMID: 19960147

The incidence of mucocoeles associated with a non-surgically treated nasal polyposis is rare. We report a rare case of nasal polyposis with asymptomatic frontal mucocoeles in a 28-year-old Malay man who presented with bilateral nasal obstruction with anosmia. Physical examination revealed bilateral grade III nasal polyps causing obstruction. Computed tomography revealed paranasal polyposis with a large polyp extending and expanding the posterior table of the frontal sinus causing erosion and thinning of its wall. Marsupialisation of the mucocoele and nasal polypectomy were done. Endoscopic sinus surgery and marsupialisation should be the treatment of choice for asymptomatic frontal mucocoele.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Pulmonary atelectasis from compression of the left main bronchus by an aortic aneurysm

Yap KH, Sulaiman S

Singapore Med J, 2009 Jul;50(7):e247-9.

PMID: 19644610

Pulmonary atelectasis may be caused by endobronchial lesions or by extrinsic compression of the bronchus. However, lung collapse due to compression from a thoracic aneurysm is uncommon. We report a 76-year-old hypertensive female patient who has pulmonary atelectasis due to an extrinsic compression from a descending thoracic aortic aneurysm, and discuss possible treatment options.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Primary thyroid lymphoma with elevated free thyroxine level

Yahaya N, Din SW, Ghazali MZ, Mustafa S

Singapore Med J, 2011 Sep;52(9):e173-6.

PMID: 21947158

Primary thyroid lymphoma (PTL) is a rare form of thyroid cancer that is known to be associated with Hashimoto thyroiditis. This association is supported by the presence of elevated titres of both antithyroglobulin and antimicrosomal antibodies in up to 95 percent of patients with PTL. Most patients with PTL present with a rapidly enlarging neck mass and compressive symptoms. The majority of thyroid cancer patients have normal levels of thyroid hormones; they are rarely hyperthyroid, with no obvious clinical features of thyrotoxicosis. We describe a patient who presented with minimal clinical features of thyrotoxicosis despite having markedly elevated serum free thyroxine and suppressed serum thyroid-stimulating hormone levels.

Matched MeSH terms: Tomography, X-Ray Computed/methods

Fulltext Computed tomography of blunt renal trauma

Razali MR, Azian AA, Amran AR, Azlin S

Singapore Med J, 2010 Jun;51(6):468-73; quiz 474.

PMID: 20658105

Renal injury is observed in 10 percent of cases of abdominal trauma, and the majority (80 percent to 90 percent) of these are attributable to blunt trauma. Intravenous urography and ultrasonography of the abdomen were previously the modalities of choice in the imaging of renal injuries. However, computed tomography (CT) is currently the imaging modality of choice in the evaluation of blunt renal injury, since it provides the exact staging of renal injuries. The purpose of this article is to describe the CT staging of renal injuries observed in blunt abdominal trauma based on the Federle Classification and the American Association for the Surgery of Trauma renal injury severity scale.

Matched MeSH terms: Tomography, X-Ray Computed/methods*

Fulltext 18F-FDG positron emission tomography/computed tomography and the "underground map" appearance in imaging Horton's arteritis

Abdul Jalil N, Abdul Rahim N, Md Shalleh N, Rossetti C

Singapore Med J, 2008 Jul;49(7):e178-82.

PMID: 18695852

A majority of the clinical use of positron emission tomography (PET)-computed tomography (CT) is related to cancer management. Its application in evaluating inflammatory diseases and pyrexia of unknown origin is becoming popular. We reviewed the fluorine-18-fluorodeoxyglucose PET-CT findings of an 80-year-old woman with nonspecific clinical presentation consisting of generalised malaise, moderately high fever and weight loss. Prior CT and magnetic resonance imaging were not helpful in providing a clinical diagnosis. The diagnosis was Horton's arteritis, and the patient responded well to high-dose steroids.

Matched MeSH terms: Tomography, X-Ray Computed/methods

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