Medical physics and other contributions from physics to medicine are relatively well known, if not well documented in Ireland. Less well known are contributions from medicine to the development of physics, which can and do occur. This paper addresses examples of all three. The methods employed include documentary research and interviews with those who share(d) the stage in the area. Documentary evidence for historical aspects of medical physics over the last century are relatively sparse and incomplete. Notwithstanding this, they can and do enable a picture to be built up of how the arrangements in place now have come about, particularly when they are accompanied by mature recollections of the participants.Good critically assessed and accessible sources have been identified covering the seventeenth to nineteenth century material presented. Examples are presented based on the work of significant contributors, each with strong Irish connections, including Robert Boyle, Erwin Schrödinger, Fearghus O'Foghludha, and Edith Stoney the first female medical physicist. Their contributions are striking and continue to be relevant now. The findings provide a rich context and heritage for medical physics in Ireland and in the international community. They will include the contemporary period in a second paper, Part 2 of this study.

Medical Physics and contributions from physics to medicine are relatively well developed in Ireland, although no comprehensive account of both is available. This paper will endeavour to address both, emphasising the former, but not overlooking the latter. The methods employed include documentary research and interviews with some of those that made significant contributions from time to time. Documentary evidence for historical aspects of the development of medical physics is relatively sparse. However, several good sources have been identified and accessed covering periods C, D, and E below. Good sources for Irish contributions/contributors from physics to medicine have been identified and are available over a longer period since the seventeenth century British enlightenment, and especially for the nineteenth and early twentieth centuries. Sources for G and H, education/training and international contributions, are limited but archival material is available. Professional bodies will be treated, where relevant, under each heading. This paper will present a summary of findings from these sources under headings including: A. The Enlightenment (17th century) period (Multiple sources) B. Nineteenth and early twentieth centuries (Multiple sources) C. Twentieth century up to late 60’s/early 70’s ( > 5 sources) D. Twentieth century from 70’s to 90’s ( > 3 sources) E. Period since the 90’s ( > 3 sources) F. Statutory developments and National Benchmarks (Multiple sources) G. Education and training initiatives ( > 3 Sources and archival material) H. Contributions to the international community (Archival material) The findings from this investigation provide a rich context and heritage for medical physics in Ireland.

Background Perforated duodenal ulcers can be treated with a covered stent. Stent migration is a severe complication, sometimes requiring surgery. Pyloric physiology during stent treatment has not been studied and mechanisms for migration are unknown. The aim of this study was to investigate the pyloric response to distention, mimicking stent treatment, using the EndoFLIP. Methods Key Results A nonsurvival study in five pigs was carried out, followed by a pilot study in one volunteer. Animals were gastroscoped during anaesthesia and the EndoFLIP was placed straddling the pylorus. Baseline distensibility readings were performed at stepwise balloon distentions to 20, 30, 40, and 50 mL, measuring pyloric cross-sectional area and pressure. Measurements were repeated after administration of a prokinetic drug and after a liquid meal. In the human study, readings were performed in conscious sedation at baseline and after stimulation with metoclopramide. During baseline readings, the pylorus was shown to open more with increasing distention together with higher amplitude motility waves. Reaching maximum distention-volume (50 mL), pyloric pressure increased significantly (P = 0.016), and motility waves disappeared. After prokinetic stimulation, the pressure decreased and the motility waves increased in frequency and amplitude. After food stimulation, the pressure stayed low and the motility showed increase in amplitude. During both tests, the pylorus showed higher pressure and lack of motility waves at maximum probe distention. Conclusions and Inferences The pylorus seems to act as a sphincter at low distention but when further dilated starts acting as a pump. Fully distended the pyloric motility disappears and the pressure remains high, suggesting that a stent with high-radial force might show less migration.

opioids disproportionally show type 3 achalasia and esophagogastric junction (EGJ) outflow obstruction phenotypes.Presence of premature (DL < 4.5 seconds) and rapid esophageal contractions (Contraction front velocity > 9 cm/s) were significantly more common in chronic daily opioid patients.Esophageal pressure topography metrics of integrated relaxation pressure (IRP), intrabolus pressure (IBP), distal latency (DL) and contraction front velocity (CFV) by opioid exposure.One hundred nineteen patients without a discernable contractile wave in any of the ten supine wet swallows were excluded from the analysis (N=1080).Chronic daily opioid intake was associated with a significantly higher IRP, IBP and CFV and reduced DL.Excluding the achalasia type 3 patients (N=49) did not alter the results. Tu1596

Background/Aims Efficient transport through the esophago-gastric junction (EGJ) requires synchronized circular and longitudinal muscle contraction of the esophagus including relaxation of the lower esophageal sphincter (LES). However, there is a scarcity of technology for measuring esophagus movements in the longitudinal (axial) direction. The aim of this study is to develop new analytical tools for dynamic evaluation of the length change and axial movement of the human LES based on the functional luminal imaging probe (FLIP) technology and to present normal signatures for the selected parameters. Methods Six healthy volunteers without hiatal hernia were included. Data were analyzed from stepwise LES distensions at 20, 30, and 40 mL bag volumes. The bag pressure and the diameter change were used for motion analysis in the LES. The cyclic bag pressure frequency was used to distinguish dynamic changes of the LES induced by respiration and secondary peristalsis. Results Cyclic fluctuations of the LES were evoked by respiration and isovolumetric distension, with phasic changes of bag pressure, diameter, length, and axial movement of the LES narrow zone. Compared to the respiration-induced LES fluctuations, peristaltic contractions increased the contraction pressure amplitude (P < 0.001), shortening (P < 0.001), axial movement (P < 0.001), and diameter change (P < 0.01) of the narrow zone. The length of the narrow zone shortened as function of the pressure increase. Conclusions FLIP can be used for evaluation of dynamic length changes and axial movement of the human LES. The method may shed light on abnormal longitudinal muscle activity in esophageal disorders.

Background: Distensibility of the gastroesophageal junction high-pressure zone (GEJHPZ) has been shown to be greater in GERD patients than in non-GERD patients by using functional luminal imaging (FLIP) and yield pressures.In GERD patients, the pressure generated by the clasp and sling muscle fibers of the esophagus are lower, and the pressure of the lower esophageal circular smooth muscle (LEC) is attenuated.Aim: The aim of this project is to evaluate the distensibility of the GEJHPZ by using FLIP in GERD subjects, and non-GERD subjects before and after muscarinic blockade with atropine.Methods: Following anesthesia, a FLIP probe was passed trans-orally into the stomach and positioned across the GEJHPZ in 7 GERD subjects, and 8 non-GERD subjects before and after atropine administration.Each balloon contained 16 impedance sensors spaced 5 mm apart.The balloon was positioned so that at least one distal sensor was in the stomach and at least one proximal sensor was in the esophagus.Minimum cross sectional area (CSA) at each impedance sensor and the pressure within the FLIP balloon were recorded as the balloon was sequentially filled to 40 ml by 10 ml increments.Key Results: CSA and pressures at 20, 30, and 40 ml were collected and analyzed.The distensibility plot was located significantly to the left in non-GERD post-atropine subjects and in GERD subjects when compared to non-GERD pre-atropine subjects.The GERD subjects' distensibility plot was further to the left than the non-GERD post-atropine subjects' plot (Fig. 1).The slopes of the distensibility plots from 20 to 40 ml of non-GERD pre-atropine, post-atropine, and GERD subjects were 1.2, 2.0, and 4.8 mm 2 /mmHg respectively (Fig. 1).Distensibility of the GEJHPZ was significantly less in the GERD patients compared to the non-GERD subjects both pre-and post-atropine at 40 ml (Table 1).Both GERD patients and non-GERD post-atropine subjects show significantly lower balloon pressures at all balloon volumes.Conclusions: Atropine increased the distensibility of the GEJHPZ in non-GERD subjects suggesting that tone and distensibity are influenced by vagal innervation in addition to passive tone.The increased distensibility in GERD subjects compared to the non-GERD subjects both pre-and post atropine suggests that there are other factors, in addition to loss of muscarinic tone, that contribute to increased distensibility in GERD patients.Average narrowest CSA in Non-GERD subjects and GERD patients

Faecal incontinence is a multi-factorial challenging problem. The maintenance of faecal continence relies on a complex voluntary and involuntary coordination between anal and colorectal activity. The aim of this study is to introduce a new method for measuring anal sphincter distensibility and function during voluntary manoeuvres like squeezing and straining as well as involuntary manoeuvres like recto-anal inhibitory reflex (RAIR) testing and slow rectal distension. A modified functional lumen imaging probe (FLIP) consisted of the rectal balloon to distend and measure the pressure in the rectum and the anal bag which contained 16 sensing electrode capable of measuring serial cross-sectional areas (CSA) of the anal bag. The CSAs were converted to functional images of the anal canal geometry. The bag pressure was also measured during anal distension. The probe was bench tested and the CSA measured by EndoFLIP system was calibrated. Four healthy volunteers (2 males/2 females) and one faecal incontinence patient were recruited for the studies. The probe was inserted in the anal canal with 2cm of the anal bag located outside the anal verge. The anal bag was distended from 0ml to 50ml, and then the volunteers were asked to rest, squeeze and strain voluntarily at specific step volumes in the anal bag. RAIR and slow rectal distension tests were also measured at three step distensions in the anal bag. The results showed that the distal end relaxed more than the proximal end during ramp distension. The anal canal length decreased as a linear function of the distending bag volume. The functional images measured during manoeuvres showed the contraction of the proximal part of the anal canal by 12mm(2) during squeezing and the relaxation by 10mm(2) during straining test. During the RAIR test, the distal part of the anal canal relaxed by 14mm(2). The distal part of the anal canal relaxed by 20mm(2) and the proximal part contracted by 10mm(2) during the slow rectal distension which mimics the defecation. In conclusion the modified EndoFLIP was capable of describing the anal distensibility and sphincteric function for different manoeuvres.

Esophageal diseases are highly prevalent and carry significant socioeconomic burden. Despite the apparently simple function of the esophagus, we still struggle to better understand its physiology and pathophysiology. The assessment of large data sets and application of multiscale mathematical organ models have gained attention as part of the Physiome Project. This has long been recognized in cardiology but has only recently gained attention for the gastrointestinal(GI) tract. The term "esophagiome" implies a holistic assessment of esophageal function, from cellular and muscle physiology to the mechanical responses that transport and mix fluid contents. These anatomical, mechanical, and physiological models underlie the development of a "virtual esophagus" modeling framework to characterize and analyze function and disease. Functional models incorporate anatomical details with sensory-motor responses, especially related to biomechanical functions such as bolus transport. Our review builds on previous reviews and focuses on assessment of detailed anatomical and geometric data using advanced imaging technology for evaluation of gastro-esophageal reflux disease (GERD), and on esophageal mechanophysiology assessed using technologies that distend the esophagus. Integration of mechanics- and physiology-based analysis is a useful characteristic of the esophagiome. Experimental data on pressures and geometric characteristics are useful for the validation of mathematical and computer models of the esophagus that may provide predictions of novel endoscopic, surgical, and pharmaceutical treatment options.

Esophageal mechanosensation describes the relationship between a mechanical stimulation of the esophageal wall, such as bag distension, and the reaction to the stimulation perceived or unperceived. When studying mechanosensation in esophageal disease, it is important to recognize that symptoms might be due to alterations at different levels of the neuromuscular system, such as alterations at the mechanoreceptor level or in the afferent mechanosensory pathways, or irregularities in the homeostatic state. One might ask if it is possible to provoke, record, and describe the multidimensional responses behind a mechanosensory experience? It is a complex system and, at a minimum, a multidisciplinary approach is needed to avoid erroneous conclusions. The multimodal study design, taking the mode, location, and parameters of stimulation into consideration, together with controlled recording of assessment parameters, is an approach that seems rational and valid. Gastrointestinal (GI) physicians of the 21th century need to have knowledge of advances in the evaluation of GI mechanical function and what provokes symptoms. Hereby, it is possible to fully appreciate the slowly emerging awareness of how GI pain symptoms should be explored and explained to patients.

Introduction We aimed to investigate irrigation and drainage characteristics of commercially available urethral catheters and determined which catheter offers the best flow characteristics. Material and methods Twelve different commercially available urethral catheters from three companies (Bard™, Rusch™ and Dover™) were investigated to compare their irrigation and drainage properties. Irrigation port, drainage port and overall cross-sectional areas for a 24Fr 3-way catheter was measured and compared. The maximum (Qmax) and average (Qavg) irrigation and drainage flow rates for each catheter was measured for 20–40 seconds using uroflowmetry. The primary endpoint was to determine which catheter offers optimal irrigation and drainage parameters. Results Overall cross-sectional area, irrigation port cross-sectional area, and drainage port cross-sectional area differed significantly for each 24Fr 3-way catheter assessed (p <0.001). The 24Fr 3-way Rusch Simplastic™ catheter consistently demonstrated the greatest maximal flow rate (Qmax: 5 ±0.3 ml/s) and average flow rate (Qavg: 4.6 ±0.2 ml/s) for irrigation. The 24Fr 3-way Dover™ catheter provided the greatest drainage properties (Qmax: 19.7 ±2 ml/s; Q avg: 15.9 ±5 ml/s). In the setting of continuous bladder irrigation, the 24Fr 3-way Rusch Simplastic™ catheter provided the highest irrigation rates (Qmax: 6.6 ±1.8 ml/s; Q avg: 4.6 ±0.9 ml/s). Conclusions Three-way catheters demonstrate significant differences in their irrigation and drainage characteristics. The type of catheter selected should be based on the appropriate prioritization of efficient bladder irrigation versus efficient bladder drainage.

Background Manometric studies are known to be inadequate in evaluating tone and opening patterns of digestive sphincters. The functional lumen imaging probe (FLIP) evolved as an important tool in evaluating sphincteric regions in the gastrointestinal tract. Aim To evaluate the potential for this technique in a pilot study on a human volunteer to 1. Evaluate the efficiency and efficacy of placing and measuring with the probe endoscopically. 2. Demonstrate if the shape and function of the pylorus could be measured using this device. 3. Evaluate the effect of the administration of a pro-kenetic drug on the function of the pylorus. Method One subject volunteered for the procedure as the probe is already approved for diagnostic use in the gastrointestinal tract. The EndoFLIP system (Crospon, Galway, Ireland) was set up as previously described using probe model EF-353. An Olympus therapeutic endoscope was inserted as per normal upper gastrointestinal investigation. The probe was inserted into the endoscope biopsy channel and positioned straddling the pylorus. Distension measurements were made with probe volumes of 20 ml, 30 ml and 40 ml before and after the administration of 10 mg of metoclopramide (Primperan). Results Activity dramatically changed in the pylorus after Primperan. The narrowest region the sphincter measured using the minimum cross sectional (CSAmin) area was relatively inactive and stable before the drug but after the CSAmin varied significantly during the 20 s measurement window, indicating changes in activity. Conclusions The FLIP system can successfully measure distensibility in the pylorus and these measurements may be useful in determining proper function in the region.

legend N2D N1D 2LPEG N2D vs. 2LPEG N1D vs. 2LPEG EFFICACY Primary analysis set, n1⁄4 275 Primary analysis set, n1⁄4 275 Primary analysis set, n1⁄4 272 Primary endpoint: Patients with successful overall bowel cleansing efficacy (HCS) [n] 253 (92.0%) 245 (89.1%) 238 (87.5%) -4.00%* [0.055] -6.91%* [0.328] Supportive secondary endpoint: Patients with successful overall bowel cleansing efficacy (BBPS) [n] 249 (90.5%) 243 (88.4%) 232 (85.3%) n.a. n.a. Primary endpoint: Excellent plus Good cleansing rate in colon ascendens (primary analysis set) [n] 87 (31.6%) 93 (33.8%) 41 (15.1%) 8.11%* [50.001] 10.32%* [50.001] Key secondary endpoint: Adenoma detection rate, colon ascendens 11.6% 11.6% 8.1% -4.80%; 12.00%** [0.106] -4.80%; 12.00%** [0.106] Key secondary endpoint: Adenoma detection rate, overall colon 26.6% 27.6% 26.8% -8.47%; 8.02%** [0.569] -7.65%; 9.11%** [0.455] Key secondary endpoint: Polyp detection rate, colon ascendens 23.3% 18.6% 16.2% -1.41%; 15.47%** [0.024] -6.12%; 10.82%** [0.268] Key secondary endpoint: Polyp detection rate, overall colon 44.0% 45.1% 44.5% -8.85%; 8.00%** [0.579] –7.78%; 9.09%** [0.478] Compliance rates (min 75% of both doses taken) [n] 235 (85.5%) 233 (84.7%) 245 (90.1%) n.a. n.a. SAFETY Safety set, n1⁄4 262 Safety set, n1⁄4 269 Safety set, n1⁄4 263 All treatment-emergent adverse events [n] 77 89 53 n.a. n.a. Patients with any related treatment-emergent adverse event [n] 30 (11.5%) 40 (14.9%) 20 (7.6%) n.a. n.a. *1⁄4 97.5% 1-sided CI; **1⁄4 95% 2-sided CI; n.a.1⁄4 not applicable. United European Gastroenterology Journal 4(5S) A219

This review aims to discuss the neurophysiology of the esophagus and new methods to assess esophageal nociception. Pain and other symptoms can be caused by diseases in the mucosa or muscular or sphincter dysfunction, together with abnormal pain processing, either in the peripheral or central nervous systems. Therefore, we present new techniques in the assessment of esophageal function and the potential role of the mucosal barrier in the generation and propagation of pain. We discuss the assessment and role of esophageal sphincters in nociception, as well as imaging and electrophysiological techniques, with examples of their use in understanding the sensory system following noxious stimuli to the esophagus. Additionally, we discuss the mechanisms behind functional diseases of the esophagus. We conclude that the new methods have identified many of the mechanisms behind malfunction of the mucosa, disturbances of muscular and sphincter functions, and the central response to different stimuli. Taken together, this has increased our understanding of esophageal disorders and may lead to new treatment modalities.

Objectives To evaluate safety of positioning and distending the functional lumen imaging probe in the pharyngo‐oesophageal segment in adults with known pharyngo‐oesophageal segment dysfunction and to obtain preliminary measurements of pharyngo‐oesophageal segment distensibility and opening during swallowing in a clinical group. Methods Prospective case series of ten adults post total laryngectomy (61–75 years) recruited from an outpatient ENT clinic. Functional lumen imaging probe was inserted trans‐nasally, and the balloon was positioned in the pharyngo‐oesophageal segment. Two 20‐ mL ramp distensions were completed, and subjects performed two dry and two 5‐ mL and 10‐ mL liquid swallows at a 12‐ mL balloon volume. Pharyngo‐oesophageal segment distensibility was calculated from cross‐sectional area (mm 2 ) and intraballoon pressure (mmHg) measures. During swallowing, extent (mm) and duration (secs) of pharyngo‐oesophageal segment opening and intraballoon pressure drop (mmHg) were evaluated. Results Functional lumen imaging probe could be passed through the pharyngo‐oesophageal segment in seven subjects, all of whom completed the protocol. During distensions, pharyngo‐oesophageal segment cross‐sectional area increased significantly (19.47–148.3 mm 2 , P < 0.001), and intraballoon pressure increased significantly (15‐ to 20‐ mL balloon volume, P = 0.005). Pharyngo‐oesophageal segment diameter (5.1 mm) increased during dry (7.4 mm), 5‐ mL (7.3 mm) and 10‐ mL (7.7 mm) liquid swallows ( P = 0.018). Pharyngo‐oesophageal segment opening duration varied across dry (1 s), 5‐ mL (0.8 s) and 10‐ mL (1.6 s) liquid swallows. Resting intraballoon pressure (25.5 mmHg) did not alter significantly during swallowing ( P = 0.656). Conclusion Functional lumen imaging probe provides novel quantitative information regarding pharyngo‐oesophageal segment distensibility and opening during swallowing in adults post total laryngectomy. No adverse events were observed in this first clinical study. Data were easy to acquire, and measures may direct candidacy for and establish effectiveness of interventions to alter pharyngo‐oesophageal segment tone.

Hiatus hernia is known to be an important risk factor for developing gastroesophageal reflux disease. We aimed to use the endoscopic functional lumen imaging probe (EndoFLIP) to evaluate the functional properties of the esophagogastric junction. EndoFLIP assessments were made in 30 patients with hiatus hernia and Barrett's esophagus, and in 14 healthy controls. The EndoFLIP was placed straddling the esophagogastric junction and the bag distended stepwise to 50 mL. Cross-sectional areas of the bag and intra-bag pressures were recorded continuously. Measurements were made in the separate sphincter components and hiatus hernia cavity. EndoFLIP measured functional aspects such as sphincter distensibility and pressure of all esophagogastric junction components and visualized all hiatus hernia present at endoscopy. The lower esophageal sphincter in hiatus hernia patients had a lower pressure (e.g. 47.7 ± 13.0 vs. 61.4 ± 19.2 mm Hg at 50-mL distension volume) and was more distensible (all P < 0.001) than the common esophagogastric junction in controls. In hiatus hernia patients, the crural diaphragm had a lower pressure (e.g. 29.6 ± 10.1 vs. 47.7 ± 13.0 mm Hg at 50-mL distension volume) and was more distensible (all P < 0.001) than the lower esophageal sphincter. There was a significant association between symptom scores in patients and EndoFLIP assessment. Conclusively, EndoFLIP was a useful tool. To evaluate the presence of a hiatus hernia and to measure the functional properties of the esophagogastric junction. Furthermore, EndoFLIP distinguished the separate esophagogastric junction components in hiatus hernia patients, and may help us understand the biomechanics of the esophagogastric junction and the mechanisms behind hiatal herniation.