{"id":{"repo_id":"strathclyde","oai_identifier":"oai:strathclyde:fb494846r"},"canonical_url":"https://search.dev.ndltd.org/etd/strathclyde/oai:strathclyde:fb494846r","repository":{"repo_id":"strathclyde","name":"University of Strathclyde","base_url":"https://stax.strath.ac.uk/catalog/oai"},"display":{"title":"Development and validation of a gastroenterology probe capable of measuring the position of the squamo-columnar junction","abstract":"The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research.","abstract_html":"The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research.","abstract_has_math":false,"creators":["Whiting, James Gerald Holland"],"institution":"University of Strathclyde","degree_name":"engd","degree_level":"doctoral-pg","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014","date_published":"2014","updated_at":"2026-07-24T04:47:15Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.doi","label":"DOI","values":["10.48730/zwcx-8y13"],"render_values":[{"text":"10.48730/zwcx-8y13","href":"https://doi.org/10.48730/zwcx-8y13","code":true}]},{"key":"dc:identifier","label":"Identifier","values":["T13723"],"render_values":[{"text":"T13723","href":null,"code":true}]}]},"links":{"outbound_url":"https://stax.strath.ac.uk/concern/theses/fb494846r","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Whiting, James Gerald Holland"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014"]},{"key":"dc:date.issued","label":"Date","values":["2014"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Biomedical Engineering"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Strathclyde"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral-pg"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["engd"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["T13723"]},{"key":"dc:identifier.doi","label":"DOI","values":["10.48730/zwcx-8y13"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://stax.strath.ac.uk/concern/theses/fb494846r"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research."]},{"key":"dc:description.abstract","label":"Abstract","values":["The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research."]},{"key":"dc:title","label":"Title","values":["Development and validation of a gastroenterology probe capable of measuring the position of the squamo-columnar junction"]}]}],"canonical_facts":{"dc:creator":["Whiting, James Gerald Holland"],"dc:date":["2014"],"dc:date.issued":["2014"],"dc:description":["The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research."],"dc:description.abstract":["The squamo-columnar junction is an important landmark in the upper gastro-oesophageal anatomy, acid reflux occurring above this causes heartburn and may lead to oesophageal cancer if prolonged. Currently no medical device takes into account the position of the squamo-columnar junction despite its importance. The aim of this doctoral work is to develop and validate a device which is capable of monitoring the position of the squamocolumnar junction with respect to simultaneous acid reflux and pressure measurements. Using Hall effect sensors on a custom flexible circuit board, and a magnet attached to the squamo-columnar junction, a device was produced which when inserted into the oesophagus, measured the relative position of the squamocolumnar junction to manometry and pH-metry catheters. The accuracy of the measurement was at most 5 millimetres, often better; a better resolution than either the high resolution manometer or custom pH device. The device was validated in-vivo, demonstrating a capability of measuring significant movement of the squamo-columnar junction during transient lower oesophageal sphincter relaxations. The accuracy of the high resolution manometer was tested, which showed significant drift, capable of causing misdiagnosis. A correction algorithm was produced which corrected linear drift, removing time dependant drift leading to significantly more accurate pressure readings. Catheter based upper gastro-oesophageal measurements have the potential to cause transient lower oesophageal sphincter relaxations by triggering mechanoreceptors in the pharynx; therefore a non-catheter based squamo-columnar junction locator was designed and tested. Using a larger magnet and significantly more sensitive Hall effect sensors and custom analogue circuitry, the squamo-columnar junction could be detected. The distance between the oesophagus and the skin is estimated to be between 8 and 9 centimetres for a healthy, non-obese male adult, the detection range for the non-catheter based squamo-columnar junction locator was 10.4 centimetres. The devices developed for this doctoral work has improved the field of gastroenterology research."],"dc:identifier":["T13723"],"dc:identifier.doi":["10.48730/zwcx-8y13"],"dc:identifier.uri":["https://stax.strath.ac.uk/concern/theses/fb494846r"],"dc:publisher.department":["Department of Biomedical Engineering"],"dc:publisher.institution":["University of Strathclyde"],"dc:title":["Development and validation of a gastroenterology probe capable of measuring the position of the squamo-columnar junction"],"dc:type.qualificationlevel":["doctoral-pg"],"dc:type.qualificationname":["engd"]},"updated_at":"2026-07-24T04:47:15Z"}