Rebecca Linke - Academia.edu (original) (raw)

Papers by Rebecca Linke

Pathology

miscarriage are not clear but can be very important for future pregnancy planning and patient cou... more miscarriage are not clear but can be very important for future pregnancy planning and patient counselling. Fetal autopsy is performed as often as possible, but some parents cannot consider autopsy at a very stressful time in their lives, and others cannot consent for cultural or religious reasons. Methods: Multi-slice CT scans were performed on 101 fetus who also underwent full autopsy. Results: The quality of the images obtained was variable, being affected by the gestation at which delivery occurred, as well as the time between death and delivery. Image quality was better with advanced gestation and minimal delay between death and delivery. Organs that were well seen included the skeleton and brain, while the pancreas and thyroid were poorly seen. The presence and position of most organs was able to be confirmed in most cases. Examples of CT images with corresponding pathology images are compared. Conclusion: Post-mortem CT has a limited role in the investigation of pregnancy losses.

Poster: "2014 CSM / R-0033 / Burkitt's lymphoma in paediatrics patients; Pictorial revie... more Poster: "2014 CSM / R-0033 / Burkitt's lymphoma in paediatrics patients; Pictorial review." by: "W. Y. Lim, R. Linke; NORTH ADELAIDE/AU"

Poster: "RANZCR-AOCR 2012 / R-0114 / Trans Tasman paediatric CT dose audit" by: "D... more Poster: "RANZCR-AOCR 2012 / R-0114 / Trans Tasman paediatric CT dose audit" by: "D. Jackson1, M. Ditchfield, J. Grimm2, J. Clark1, F. Wilson, E. Onikul2, J. Pereira2, R. Linke, G. Long2, F. Bettenay, M. Phillips; 1Melbourne/AU, 2AU"

Journal of Medical Imaging and Radiation Oncology, 2016

Introduction: Diagnostic reference levels (DRL) of procedures involving ionising radiation are im... more Introduction: Diagnostic reference levels (DRL) of procedures involving ionising radiation are important tools for optimising radiation doses delivered to patients and to identify cases where the levels of dose are unusually high. This is particularly important for paediatric patients undergoing fluoroscopic examinations as these examinations can be associated with a high radiation dose. In this study, a large amount of paediatric fluoroscopic data has been analysed to: 1 establish local DRL, 2 identify the most significant factors determining radiation dose to patients, and 3 modify fluoroscopic techniques to optimise the examination protocols. Methods: Paediatric fluoroscopic studies performed at our institution from April 2010 to May 2015 have been retrospectively analysed to determine range, mean, 75th and 95th percentiles of Dose-Area Product (DAP) and fluoroscopic screening time for Micturating Cystourethrography (MCU), Airway, Airway and Swallow, Barium Swallow and Meal, Barium Follow Through and Barium Enema studies. Results: Currently, no Australian paediatric fluoroscopic DRL data are available for comparison and thus our data can only be compared with international published data. No major changes to examination protocols or modification to fluoroscopic techniques were found necessary as our data compared well with the international published values. Conclusion: The dose delivered to patients depend on a number of factors particularly the experience of the operators. However, DRL are also important, as shown in this study, as they enable best practice by providing feedback to the operators on their performance and benchmarking the institution with other institutions.

Journal of medical radiation sciences, 2016

The gold standard in general radiography is to place a radiopaque anatomical side marker in the f... more The gold standard in general radiography is to place a radiopaque anatomical side marker in the field of view for each radiographic image prior to exposure. The advent of digital radiography has allowed for anatomical side markers to be digitally added to films as part of post-processing. The aim of this audit was to identify whether general X-ray images performed in a tertiary Women's and Children's Hospital were being appropriately annotated with a definitive side marker, and to identify factors that may contribute to inappropriately labelled images. Four hundred images from 201 patients' examinations occurring within a randomly selected time period were assessed to ascertain whether radiographic anatomical side markers were visible when images were viewed via the hospitals main viewing platform. The audit occurred in January 2014. The scope included both mobile and in-department general X-ray examinations, with the patient age range extending from 1 day to 18 years. O...

Journal of Pediatric Surgery, 2016

Background: This study appraises the diagnostic quality of ultrasound for acute appendicitis in c... more Background: This study appraises the diagnostic quality of ultrasound for acute appendicitis in children and consequently challenges the perception of inferior accuracy and suitability compared to computed tomography (CT). Methods: Radiologist reports for consecutive "query appendicitis" ultrasound studies were retrieved from a hospital database for the study period 2009-2014. Children who subsequently underwent appendicectomy were identified. Corresponding operative and histopathology findings were evaluated. Diagnostic accuracy of ultrasound was determined by analyzing overall accuracy, sensitivity, specificity, predictivity, and likelihood ratios. Results: A total of 3799 ultrasound examinations were evaluated. Mean age was 11.5 ± 3.8 years. The proportion of patients investigated with preoperative ultrasound was 59.9% (1103/1840). Appendix visualization rate was 91.7%. Overall diagnostic accuracy was 95.5%. Sensitivity and specificity values were 97.1% (95.9-98.1; 95% CI) and 94.8% (93.9-95.6; 95% CI), respectively. Separate analysis of only ultrasound positive and negative examinations (i.e., excluding nondiagnostic examinations) confirmed sensitivity and specificity values of 98.8% and 98.3%. Conclusion: In this largest reported single institution series of ultrasound examinations for appendicitis, we report benchmark standard quality of diagnostic accuracy and visualization rates. Given the radiation and cost implications of CT, there is a strong argument to recommend ultrasound as the primary imaging modality. Diagnostic Study-Level II.

Journal of medical imaging and radiation oncology, Jan 5, 2016

Diagnostic Reference Levels (DRL) of procedures involving ionizing radiation are important tools ... more Diagnostic Reference Levels (DRL) of procedures involving ionizing radiation are important tools to optimizing radiation doses delivered to patients and in identifying cases where the levels of doses are unusually high. This is particularly important for paediatric patients undergoing computed tomography (CT) examinations as these examinations are associated with relatively high-dose. Paediatric CT studies, performed at our institution from January 2010 to March 2014, have been retrospectively analysed to determine the 75th and 95th percentiles of both the volume computed tomography dose index (CTDIvol ) and dose-length product (DLP) for the most commonly performed studies to: establish local diagnostic reference levels for paediatric computed tomography examinations performed at our institution, benchmark our DRL with national and international published paediatric values, and determine the compliance of CT radiographer with established protocols. The derived local 75th percentile ...

European Radiology, 2015

Objectives To evaluate paediatric CT dosimetry in Australia and New Zealand and calculate size-sp... more Objectives To evaluate paediatric CT dosimetry in Australia and New Zealand and calculate size-specific dose estimates (SSDEs) for chest and abdominal examinations. Methods Eight hospitals provided data from 12 CT systems for 1462 CTs in children aged 0-15. Imaging data were recorded for eight examinations: head (trauma, shunt), temporal bone, paranasal sinuses, chest (mass) and chest HRCT (highresolution CT), and abdomen/pelvis (mass/inflammation). Dose data for cranial examinations were categorised by age and SSDEs by lateral dimension. Diagnostic reference ranges (DRRs) were defined by the 25th and 75th percentiles. Centralised image quality assessment was not undertaken.

Australasian Radiology, 1994

In patients presenting with intermittent claudication, Colour Duplex Ultrasound (CDU) examination... more In patients presenting with intermittent claudication, Colour Duplex Ultrasound (CDU) examination of the femoro-popliteal segment has been proposed as a screening modality. Those patients with atheromatous lesions suitable for percutaneous transluminal angioplasty (PTA) could proceed to diagnostic angiography. Patients with long segment occlusive disease demonstrated by CDU, who were not considered suitable candidates for surgery, would not require angiographic examination. This prospective study was performed on 46 limbs in 25 consecutive patients who presented for investigation of claudication. There was close correlation between the two methods in the demonstration of high-grade stenoses and occluded segments. Using angiography as the 'gold standard' this study indicated a diagnostic accuracy for CDU of 93% with a sensitivity of 89% and a specificity of 95%. Angiography tended to show longer occluded segments than CDU. Colour Duplex Ultrasound shows promise as a screening investigation in patients with intermittent claudication to detect lesions that may be suitable for PTA.

Fetal Diagnosis and Therapy, 1999

Objective: To determine the influence of antenatal ultrasound on the management of exomphalos. Me... more Objective: To determine the influence of antenatal ultrasound on the management of exomphalos. Methods: Retrospective case note review of 23 fetuses and infants referred to our institution with either a pre- or postnatal diagnosis of exomphalos over a 7-year period. Results: There were 21 cases of exomphalos of which 18 were correctly diagnosed on antenatal ultrasound by 18 weeks’ gestation. There were 2 false-positives and 3 false-negatives, including 1 case of amniotic band syndrome with an abdominal wall defect and 1 morphologically normal fetus. Associated anomalies were correctly identified in 12 but incorrectly reported in 8. Maternal serum α-fetoprotein levels were abnormal in 61% of cases of abdominal wall defects in this series. Amniocentesis was performed in 12 and cordocentesis in 1. There were 13 terminations, including 2 trisomy 18s and 1 trisomy 13. Two fetal deaths followed amniocentesis. Of the 10 live births, 9 had their exomphalos repaired with a 1-year survival ra...

Cardiovascular and Interventional Radiology, 1992

A 14-month-old boy with severe esophageal strictures following ingestion of potassium hydroxide i... more A 14-month-old boy with severe esophageal strictures following ingestion of potassium hydroxide is described. Initially, treatment was by surgical bougienage but following esophageal perforation, 65 balloon dilatations were performed over an 8-month period using a retrograde approach via a feeding gastrostomy without anesthesia or sedation. A further nine dilatations in the following 6 months were performed using a per-oral approach after establishment of fult oral nutrition and removal of the gastrostomy. The main advantage of the retrograde approach was the large number of dilatations that could be performed without anesthesia in an infant. This has allowed nonoperative treatment of a high grade caustic esophageal stricture which would otherwise have required esophageal replacement.

Pediatric Radiology, 1992

A review of barium meal studies in 32 cases of

Pediatric Radiology, 1992

A review of barium meal studies in 32 cases of

Pathology

miscarriage are not clear but can be very important for future pregnancy planning and patient cou... more miscarriage are not clear but can be very important for future pregnancy planning and patient counselling. Fetal autopsy is performed as often as possible, but some parents cannot consider autopsy at a very stressful time in their lives, and others cannot consent for cultural or religious reasons. Methods: Multi-slice CT scans were performed on 101 fetus who also underwent full autopsy. Results: The quality of the images obtained was variable, being affected by the gestation at which delivery occurred, as well as the time between death and delivery. Image quality was better with advanced gestation and minimal delay between death and delivery. Organs that were well seen included the skeleton and brain, while the pancreas and thyroid were poorly seen. The presence and position of most organs was able to be confirmed in most cases. Examples of CT images with corresponding pathology images are compared. Conclusion: Post-mortem CT has a limited role in the investigation of pregnancy losses.

Poster: "2014 CSM / R-0033 / Burkitt's lymphoma in paediatrics patients; Pictorial revie... more Poster: "2014 CSM / R-0033 / Burkitt's lymphoma in paediatrics patients; Pictorial review." by: "W. Y. Lim, R. Linke; NORTH ADELAIDE/AU"

Poster: "RANZCR-AOCR 2012 / R-0114 / Trans Tasman paediatric CT dose audit" by: "D... more Poster: "RANZCR-AOCR 2012 / R-0114 / Trans Tasman paediatric CT dose audit" by: "D. Jackson1, M. Ditchfield, J. Grimm2, J. Clark1, F. Wilson, E. Onikul2, J. Pereira2, R. Linke, G. Long2, F. Bettenay, M. Phillips; 1Melbourne/AU, 2AU"

Journal of Medical Imaging and Radiation Oncology, 2016

Introduction: Diagnostic reference levels (DRL) of procedures involving ionising radiation are im... more Introduction: Diagnostic reference levels (DRL) of procedures involving ionising radiation are important tools for optimising radiation doses delivered to patients and to identify cases where the levels of dose are unusually high. This is particularly important for paediatric patients undergoing fluoroscopic examinations as these examinations can be associated with a high radiation dose. In this study, a large amount of paediatric fluoroscopic data has been analysed to: 1 establish local DRL, 2 identify the most significant factors determining radiation dose to patients, and 3 modify fluoroscopic techniques to optimise the examination protocols. Methods: Paediatric fluoroscopic studies performed at our institution from April 2010 to May 2015 have been retrospectively analysed to determine range, mean, 75th and 95th percentiles of Dose-Area Product (DAP) and fluoroscopic screening time for Micturating Cystourethrography (MCU), Airway, Airway and Swallow, Barium Swallow and Meal, Barium Follow Through and Barium Enema studies. Results: Currently, no Australian paediatric fluoroscopic DRL data are available for comparison and thus our data can only be compared with international published data. No major changes to examination protocols or modification to fluoroscopic techniques were found necessary as our data compared well with the international published values. Conclusion: The dose delivered to patients depend on a number of factors particularly the experience of the operators. However, DRL are also important, as shown in this study, as they enable best practice by providing feedback to the operators on their performance and benchmarking the institution with other institutions.

Journal of medical radiation sciences, 2016

The gold standard in general radiography is to place a radiopaque anatomical side marker in the f... more The gold standard in general radiography is to place a radiopaque anatomical side marker in the field of view for each radiographic image prior to exposure. The advent of digital radiography has allowed for anatomical side markers to be digitally added to films as part of post-processing. The aim of this audit was to identify whether general X-ray images performed in a tertiary Women's and Children's Hospital were being appropriately annotated with a definitive side marker, and to identify factors that may contribute to inappropriately labelled images. Four hundred images from 201 patients' examinations occurring within a randomly selected time period were assessed to ascertain whether radiographic anatomical side markers were visible when images were viewed via the hospitals main viewing platform. The audit occurred in January 2014. The scope included both mobile and in-department general X-ray examinations, with the patient age range extending from 1 day to 18 years. O...

Journal of Pediatric Surgery, 2016

Background: This study appraises the diagnostic quality of ultrasound for acute appendicitis in c... more Background: This study appraises the diagnostic quality of ultrasound for acute appendicitis in children and consequently challenges the perception of inferior accuracy and suitability compared to computed tomography (CT). Methods: Radiologist reports for consecutive "query appendicitis" ultrasound studies were retrieved from a hospital database for the study period 2009-2014. Children who subsequently underwent appendicectomy were identified. Corresponding operative and histopathology findings were evaluated. Diagnostic accuracy of ultrasound was determined by analyzing overall accuracy, sensitivity, specificity, predictivity, and likelihood ratios. Results: A total of 3799 ultrasound examinations were evaluated. Mean age was 11.5 ± 3.8 years. The proportion of patients investigated with preoperative ultrasound was 59.9% (1103/1840). Appendix visualization rate was 91.7%. Overall diagnostic accuracy was 95.5%. Sensitivity and specificity values were 97.1% (95.9-98.1; 95% CI) and 94.8% (93.9-95.6; 95% CI), respectively. Separate analysis of only ultrasound positive and negative examinations (i.e., excluding nondiagnostic examinations) confirmed sensitivity and specificity values of 98.8% and 98.3%. Conclusion: In this largest reported single institution series of ultrasound examinations for appendicitis, we report benchmark standard quality of diagnostic accuracy and visualization rates. Given the radiation and cost implications of CT, there is a strong argument to recommend ultrasound as the primary imaging modality. Diagnostic Study-Level II.

Journal of medical imaging and radiation oncology, Jan 5, 2016

Diagnostic Reference Levels (DRL) of procedures involving ionizing radiation are important tools ... more Diagnostic Reference Levels (DRL) of procedures involving ionizing radiation are important tools to optimizing radiation doses delivered to patients and in identifying cases where the levels of doses are unusually high. This is particularly important for paediatric patients undergoing computed tomography (CT) examinations as these examinations are associated with relatively high-dose. Paediatric CT studies, performed at our institution from January 2010 to March 2014, have been retrospectively analysed to determine the 75th and 95th percentiles of both the volume computed tomography dose index (CTDIvol ) and dose-length product (DLP) for the most commonly performed studies to: establish local diagnostic reference levels for paediatric computed tomography examinations performed at our institution, benchmark our DRL with national and international published paediatric values, and determine the compliance of CT radiographer with established protocols. The derived local 75th percentile ...

European Radiology, 2015

Objectives To evaluate paediatric CT dosimetry in Australia and New Zealand and calculate size-sp... more Objectives To evaluate paediatric CT dosimetry in Australia and New Zealand and calculate size-specific dose estimates (SSDEs) for chest and abdominal examinations. Methods Eight hospitals provided data from 12 CT systems for 1462 CTs in children aged 0-15. Imaging data were recorded for eight examinations: head (trauma, shunt), temporal bone, paranasal sinuses, chest (mass) and chest HRCT (highresolution CT), and abdomen/pelvis (mass/inflammation). Dose data for cranial examinations were categorised by age and SSDEs by lateral dimension. Diagnostic reference ranges (DRRs) were defined by the 25th and 75th percentiles. Centralised image quality assessment was not undertaken.

Australasian Radiology, 1994

In patients presenting with intermittent claudication, Colour Duplex Ultrasound (CDU) examination... more In patients presenting with intermittent claudication, Colour Duplex Ultrasound (CDU) examination of the femoro-popliteal segment has been proposed as a screening modality. Those patients with atheromatous lesions suitable for percutaneous transluminal angioplasty (PTA) could proceed to diagnostic angiography. Patients with long segment occlusive disease demonstrated by CDU, who were not considered suitable candidates for surgery, would not require angiographic examination. This prospective study was performed on 46 limbs in 25 consecutive patients who presented for investigation of claudication. There was close correlation between the two methods in the demonstration of high-grade stenoses and occluded segments. Using angiography as the 'gold standard' this study indicated a diagnostic accuracy for CDU of 93% with a sensitivity of 89% and a specificity of 95%. Angiography tended to show longer occluded segments than CDU. Colour Duplex Ultrasound shows promise as a screening investigation in patients with intermittent claudication to detect lesions that may be suitable for PTA.

Fetal Diagnosis and Therapy, 1999

Objective: To determine the influence of antenatal ultrasound on the management of exomphalos. Me... more Objective: To determine the influence of antenatal ultrasound on the management of exomphalos. Methods: Retrospective case note review of 23 fetuses and infants referred to our institution with either a pre- or postnatal diagnosis of exomphalos over a 7-year period. Results: There were 21 cases of exomphalos of which 18 were correctly diagnosed on antenatal ultrasound by 18 weeks’ gestation. There were 2 false-positives and 3 false-negatives, including 1 case of amniotic band syndrome with an abdominal wall defect and 1 morphologically normal fetus. Associated anomalies were correctly identified in 12 but incorrectly reported in 8. Maternal serum α-fetoprotein levels were abnormal in 61% of cases of abdominal wall defects in this series. Amniocentesis was performed in 12 and cordocentesis in 1. There were 13 terminations, including 2 trisomy 18s and 1 trisomy 13. Two fetal deaths followed amniocentesis. Of the 10 live births, 9 had their exomphalos repaired with a 1-year survival ra...

Cardiovascular and Interventional Radiology, 1992

A 14-month-old boy with severe esophageal strictures following ingestion of potassium hydroxide i... more A 14-month-old boy with severe esophageal strictures following ingestion of potassium hydroxide is described. Initially, treatment was by surgical bougienage but following esophageal perforation, 65 balloon dilatations were performed over an 8-month period using a retrograde approach via a feeding gastrostomy without anesthesia or sedation. A further nine dilatations in the following 6 months were performed using a per-oral approach after establishment of fult oral nutrition and removal of the gastrostomy. The main advantage of the retrograde approach was the large number of dilatations that could be performed without anesthesia in an infant. This has allowed nonoperative treatment of a high grade caustic esophageal stricture which would otherwise have required esophageal replacement.

Pediatric Radiology, 1992

A review of barium meal studies in 32 cases of

Pediatric Radiology, 1992

A review of barium meal studies in 32 cases of