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PubMed1990

Digital tumor fluoroscopy (DTF)--a new direct imaging system in the therapy planning for brain tumors.

Digital Tumor Fluoroscopy is an expanded x-ray video chain optimized to iodine contrast with an extended Gy scale up to 64000 Gy values. Series of pictures are taken before and after injection of contrast medium. With the most recent unit, up to ten images can be taken and stored. The microprogrammable processor allows the subtraction of images recorded at any moment of the examination. Dynamic views of the distribution of contrast medium in the intravasal and extravasal spaces of brain and tumor tissue are gained by the subtraction of stored images. Tumors can be differentiated by studying the storage and drainage behavior of the contrast medium during the period of examination. Meningiomas store contrast medium very intensively during the whole time of investigation, whereas astrocytomas grade 2-3 pick it up less strongly at the beginning and release it within 2 min. Glioblastomas show a massive but delayed accumulation of contrast medium and a decreased flow-off-rate. In comparison with radiography and MR-imaging the most important advantage of Digital Tumor Fluoroscopy is that direct information on tumor localization is gained in relation to the skull-cap. This enables the radiotherapist to mark the treatment field directly on the skull. Therefore it is no longer necessary to calculate the tumor volume from several CT scans for localization. In radiotherapy Digital Tumor Fluoroscopy a unit combined with a simulator can replace CT planning. This would help overcome the disadvantages arising from the lack of a collimating system, and the inaccuracies which result from completely different geometric relationships between a CT unit and a therapy machine.

Astrocytoma↗
PubMed2004

Feasibility of synchronization of real-time tumor-tracking radiotherapy and intensity-modulated radiotherapy from viewpoint of excessive dose from fluoroscopy.

PURPOSE: Synchronization of the techniques in real-time tumor-tracking radiotherapy (RTRT) and intensity-modulated RT (IMRT) is expected to be useful for the treatment of tumors in motion. Our goal was to estimate the feasibility of the synchronization from the viewpoint of excessive dose resulting from the use of fluoroscopy. METHODS AND MATERIALS: Using an ionization chamber for diagnostic X-rays, we measured the air kerma rate, surface dose with backscatter, and dose distribution in depth in a solid phantom from a fluoroscopic RTRT system. A nominal 50-120 kilovoltage peak (kVp) of X-ray energy and a nominal 1-4 ms of pulse width were used in the measurements. RESULTS: The mean +/- SD air kerma rate from one fluoroscope was 238.8 +/- 0.54 mGy/h for a nominal pulse width of 2.0 ms and nominal 100 kVp of X-ray energy at the isocenter of the linear accelerator. The air kerma rate increased steeply with the increase in the X-ray beam energy. The surface dose was 28-980 mGy/h. The absorbed dose at a 5.0-cm depth in the phantom was 37-58% of the peak dose. The estimated skin surface dose from one fluoroscope in RTRT was 29-1182 mGy/h and was strongly dependent on the kilovoltage peak and pulse width of the fluoroscope and slightly dependent on the distance between the skin and isocenter. CONCLUSION: The skin surface dose and absorbed depth dose resulting from fluoroscopy during RTRT can be significant if RTRT is synchronized with IMRT using a multileaf collimator. Precise estimation of the absorbed dose from fluoroscopy during RT and approaches to reduce the amount of exposure are mandatory.

Calibration↗
PubMed2006

Fluoroscopy-assisted thoracoscopic resection of pulmonary nodules after computed tomography--guided bronchoscopic metallic coil marking.

OBJECTIVE: To localize small and deeply situated pulmonary nodules during thoracoscopy with roentgenographic fluoroscopy, we developed a marking procedure that uses a metallic coil. METHODS: Nine patients underwent video-assisted thoracoscopic surgery for the removal of 11 pulmonary lesions. Fluoroscopy-assisted thoracoscopic surgery after computed tomography-guided bronchoscopic metallic coil marking was performed with an ultrathin bronchoscope, with simulation by means of virtual bronchoscopy. During thoracoscopy, a C-arm-shaped roentgenographic fluoroscope was used to detect the radiopaque nodules. RESULTS: The marking procedure took 15 to 60 minutes from insertion to removal of the bronchoscope. There were no complications from the marking, and all 11 nodules were easily localized by means of thoracoscopy. The metallic coil showed the nodules on the fluoroscopic monitor, which aided in nodule manipulation. Nodules were completely resected under thoracoscopic guidance, except in one case in which a minithoracotomy was performed at an early stage of the trial. The pathologic diagnosis was primary adenocarcinoma in 9 patients, pulmonary metastasis from colon cancer in 1 patient, and pulmonary lymph node in 1 patient. Two cases of bronchioloalveolar adenocarcinoma with an invasive component and a well-differentiated adenocarcinoma were converted to open thoracotomy to perform curative lobectomy. CONCLUSIONS: In this pilot study computed tomography-guided transbronchial metallic coil marking with an ultrathin bronchoscope with virtual bronchoscopic simulation might be a useful method for the fluoroscopy-assisted thoracoscopic resection of pulmonary nodules.

Adult↗
PubMedDate not supplied

Ultrasound-guided lumbar medial-branch block: a clinical study with fluoroscopy control.

BACKGROUND AND OBJECTIVES: For diagnostic lumbar medial-branch blocks, fluoroscopic guidance is considered mandatory, but this technique comes with radiation exposure. The clinical feasibility of the ultrasound-guided lumbar medial-branch block has been demonstrated. We evaluated the success rate and validity of this new method by use of fluoroscopy controls in patients previously diagnosed with lumbar facet joint-mediated pain. METHODS: In 20 patients, 101 lumbar medial-branch blocks were performed under ultrasound guidance. The target point was the groove at the cephalad margin of the transverse process adjacent to the superior articular process. C-arm fluoroscopy was performed afterward to confirm the needle position. Pain scores were assessed by use of visual analog scale (VAS 0 to 100). RESULTS: All 101 needles were placed in the correct lumbar segment. Ninety-six of the 101 needletips were in the correct position with a success rate of 95%. Two needles were associated with intravascular spread of the contrast dye. VAS score was reduced from 52 to 16 after the block. CONCLUSIONS: Ultrasound-guided lumbar medial-branch blocks can be performed with a high success rate. However, to be completely independent from fluoroscopy controls, this technique requires further studies regarding the detection of intravascular spread.

Adult↗
PubMedDate not supplied

Use of intraoperative isocentric C-arm 3D fluoroscopy for sextant percutaneous pedicle screw placement: case report and review of the literature.

BACKGROUND CONTEXT: Three-dimensional (3D) fluoroscopy-based image guidance system using an isocentric C-arm (Iso-C) fluoroscope was shown to be as effective as computed tomography-based systems in guiding the accurate percutaneous placement of lumbar pedicle screws in cadavers. To date, however, no description is available of the intraoperative use of 3D fluoroscopy to guide lumbar pedicle screw placement in an actual spinal fusion procedure. PURPOSE: We report a case in which isocentric 3D fluoroscopic images, along with image-guidance software, were used to guide the placement of percutaneous pedicle screws for fusion in a patient with degenerative spondylolisthesis. STUDY DESIGN/SETTING: Operating room of a large academic medical center during the placement of percutaneous pedicle screws in a patient with degenerative spondylolisthesis. METHODS: A percutaneous dynamic reference array was attached to the L3 spinous process. A satisfactory image set was obtained and automatically registered. The L4 and L5 pedicles were localized, and pedicle holes were then cannulated, drilled and tapped. A screw was then inserted using the Sextant system for percutaneous pedicle screws. In this manner, bilateral pedicle screws were inserted into the L4-L5 pedicles. All steps of pedicle cannulation were performed under Iso-C 3D image guidance. RESULTS: A postoperative computed tomography scan showed accurate placement of all pedicle screws. The patient experienced an improvement in leg pain with no new neurologic deficits. CONCLUSIONS: The present case is the first case to demonstrate the intraoperative use of a 3D fluoroscopy-based image-guidance system for accurate navigation during lumbar pedicle screw placement.

Bone Screws↗
PubMed2002

Fluoroscopy-assisted thoracoscopic resection of lung nodules marked with lipiodol.

BACKGROUND: To localize small and deeply situated pulmonary nodules under thoracoscopy with roentgenographic fluoroscopy, we developed a marking procedure that uses both lipiodol and colored collagen. METHODS: Pulmonary nodules were marked with 0.4 mL of lipiodol under computed tomography. The visceral pleura near each nodule was marked with 1 mL of colored collagen, ie, a mixture of atelocollagen and methylene blue. Nodules were marked more than 1 day before thoracoscopy. At thoracoscopy, C-arm-shaped roentgenographic fluoroscopy was used to detect the radiopaque nodules. Eighteen nodules in 16 patients were localized by this procedure. The nodules had an average diameter of 7 mm (range: 4 to 10 mm) and were located an average distance of 19 mm (range: 8 to 30 mm) from the pleural surface under computed tomographic measurement. RESULTS: There were no complications from the marking procedure except for pneumothorax in 1 patient who required chest tube drainage for additional marking. All 18 nodules could be easily localized at thoracoscopy. The colored collagen revealed the pleura near the nodules. The lipiodol showed the nodules on the fluoroscopic monitor, which was used to guide the forceps to grasp the nodules. All of the nodules could be resected completely under thoracoscopy without adding minithoracotomy. The pathologic diagnosis was malignant tumor in 9 patients, atypical adenomatous hyperplasia in 3, and benign lesion in 4. CONCLUSIONS: A marking procedure that uses both lipiodol and colored collagen can localize small and deeply situated pulmonary nodules under fluoroscopy and facilitate safe and successful thoracoscopic resection.

Aged↗
PubMedDate not supplied

Can clinicians accurately assess esophageal dilation without fluoroscopy?

This study questioned whether clinicians could determine the success of esophageal dilation accurately without the aid of fluoroscopy. Twenty patients were enrolled with the diagnosis of distal esophageal stenosis, including benign peptic stricture (17), Schatski's ring (2), and squamous cell carcinoma of the esophagus (1). Dilation attempts using only Maloney dilators were monitored fluoroscopically by the principle investigator, the physician and patient being unaware of the findings. Physicians then predicted whether or not their dilations were successful, and they examined various features to determine their usefulness in predicting successful dilation. They were able to predict successful dilation accurately in 97% of the cases studied; however, their predictions of unsuccessful dilation were correct only 60% of the time. Features helpful in predicting passage included easy passage of the dilator (98%) and the patient feeling the dilator in the stomach (95%). Excessive resistance suggesting unsuccessful passage was an unreliable feature and was often due to the dilator curling in the stomach. When Maloney dilators are used to dilate simple distal strictures, if the physician predicts successful passage, he is reliably accurate without the use of fluoroscopy; however, if unsuccessful passage is suspected, fluoroscopy must be used for confirmation.

Aged↗
PubMed1995

Fluoroscopy is not necessary for Maloney dilation of chronic esophageal strictures.

The use of fluoroscopic guidance for Maloney dilation is controversial. In order to determine if fluoroscopic analysis would enhance the success of dilation and increase recognition of adverse events, we prospectively studied 125 Maloney dilations in 80 patients (mean age, 69.3 years) with mild esophageal strictures. Most strictures (89%) resulted from acid-peptic disease. Operators included two staff physicians (5 and 25 years of experience) and one trainee (1 year of experience). Dilations were performed with the patient seated upright and the operator noting the presence and amount of resistance (dilator size, 36F to 60F; median, 50F). The fluoroscopic monitor was not visible to the operator, and the results were recorded by an observer who did not communicate with the operator. Operator assessment of Maloney dilation was correct in 122 of 125 procedures. Two failures were interpreted as no passage by the operator when passage had occurred as confirmed by fluoroscopy. One failure was interpreted as passage when no passage had occurred as indicated by fluoroscopy. Adverse events included 1 episode of tracheal intubation and failure to recognize the dilator tip curling in the esophagus as observed by fluoroscopy in 6 of 125 (4.8%) procedures. Operator assessment of resistance was more often associated with curling of the dilator on the greater curve of the stomach than with an esophageal stricture. Greater operator experience tended to correlate with increased success and correct interpretation of dilation. Maloney dilations performed with patients at 30 degrees rather than upright at 90 degrees were associated with a marked increase in unsuccessful dilator passage and curling of dilator tip.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1980

Diagnostic advantages of manual compression fluoroscopy in the radiologic work-up of vomiting neonates.

This paper describes a simple and effective fluoroscopic technique that remarkably improves diagnostic accuracy when evaluating vomiting newborns. The technique also minimizes the time of the examination and the radiation dose to the patient and radiology personnel. Several examples are presented illustrating the superiority of gloved hand or nonopaque compression technique to conventional contrast radiography, emphasizing babies with pyloric stenosis and midgut malrotation. The technical limitations and diagnostic pitfalls of conventional contrast modalities are compared to the highly diagnostic images obtained with manual compression fluoroscopy. All of the classic radiographic signs of pyloric stenosis can be mimicked by antral spasm or pylorospasm. Gloved hand compression overcomes antral spasm and clearly shows the true length and diameter of the pyloric canal in these two conditions. Malposition of the duodenojejunal junction is the only consistently diagnostic sign of midgut malrotation. Nonfixation of the duodenojejunal junction can be competently assessed by compression fluoroscopy, confirming malrotation and midgut volvulus simultaneously and bringing the patient to operation much sooner than with less precise conventional techniques. Gloved hand compression technique also evaluates stenotic areas in the upper gastrointestinal tract, distinguishing spasm from organic marrowing and clearly identifying those which need surgical intervention. Facilitating intubation of the duodenum is a final contribution of compression fluoroscopy.

False Negative Reactions↗
PubMed2006

Intraoperative fragment detection during percutaneous nephrolithotomy: evaluation of high magnification rotational fluoroscopy combined with aggressive nephroscopy.

PURPOSE: Percutaneous nephrolithotomy effectively treats large volume renal calculi but relies on postoperative imaging to judge success. We evaluated the effectiveness of maximizing intraoperative imaging through combined high resolution fluoroscopy and flexible nephroscopy. MATERIALS AND METHODS: Percutaneous nephrolithotomy was performed cooperatively with a radiologist in an interventional radiology suite equipped with a ceiling mounted, high resolution C-arm. Aggressive rigid and flexible nephroscopy was performed. At the conclusion patients were prospectively classified as radiologically and/or endoscopically stone-free. Postoperative noncontrast CT allowed fragment classification as stone-free, 2 mm or less, 2 to 4 mm and greater than 4 mm. RESULTS: The average stone dimension +/- SEM was 579 +/- 77 mm(2) in 25 consecutive renal units. CT demonstrated that 15 renal units (60%) were stone-free after the primary procedure, while 2 (8%), 5 (20%) and 3 (12%) had fragments 2 or less, 2 to 4 and greater than 4 mm, respectively. Of 21 renal units considered endoscopically and fluoroscopically stone-free postoperative CT demonstrated that 6 had residual fragments, of which all were less than 4 mm. All 4 renal units not considered radiologically and endoscopically stone-free had fragments on CT. Intraoperative fluoroscopy after nephroscopy demonstrated fragments in 36% of renal units, of which after further nephroscopy 78% were stone-free on CT. The sensitivity of intraoperative imaging with reference to the gold standard of postoperative CT was 40%, 38% and 100% at thresholds of 0, 2 and 4 mm, respectively. Specificity was 100%, 94% and 95%, respectively. CONCLUSIONS: Flexible nephroscopy combined with high magnification rotational fluoroscopy allows sensitive and specific intraoperative detection of residual fragments, enabling immediate removal or the planning of necessary second look nephroscopy.

Endoscopy↗
PubMed2000

CT fluoroscopy for thoracic interventional procedures.

In the past several years, CT fluoroscopy has proved a valuable new technique in guiding the performance of intrathoracic procedures. Several approaches to using CT fluoroscopy are discussed. We have found an interrupted, real-time technique optimal to facilitate biopsy of percutaneous lung nodules, particularly small lesions. The technique is also valuable in assisting thoracic drainage procedures. This article also discusses the use of CT fluoroscopy to guide transbronchial needle aspiration, which is another potentially important application.

Biopsy, Needle↗
PubMed1998

Comparison of endoscopy and radiographic fluoroscopy in the evaluation of pediatric congenital airway abnormalities.

In order to assess the accuracy of conventional dynamic radiographic studies compared to endoscopy in the diagnosis of congenital airway abnormalities, we performed a retrospective chart review for the period between July 1991 to June 1996. A total of 186 patients were identified who required hospitalization for their respiratory status as a result of a congenital airway abnormality. Of these, 19% had both endoscopy and conventional dynamic radiographic evaluation (airway fluoroscopy, barium esophagography, or both). Eleven percent had fluoroscopy only, 62% had endoscopy only, and 9% had neither. In those patients who underwent both endoscopic and conventional dynamic radiographic evaluation, endoscopy was considered to be the definitive procedure for diagnosis. Laryngomalacia was present in 94% of these patients. Thirteen patients had multiple sites of airway abnormalities on endoscopy, and a total of 51 abnormalities were identified. Dynamic radiographic evaluation was correct in four, was suggestive of the abnormality in 12, did not recognize an abnormality in 33, and suggested a different diagnosis (not corresponding to endoscopy) in two. Thus, airway fluoroscopy and/or barium esophagography were correct or suggestive in 16 of 51 abnormalities (31%). We conclude that endoscopy is required in the majority of hospitalized patients for the precise diagnosis of a congenital airway abnormality. Conventional dynamic radiographic studies are helpful to confirm a suspected diagnosis in patients with a strong clinical history and physical examination. When the diagnosis is not clear based on the patient presentation, endoscopy is more definitive than conventional dynamic radiography in identifying pediatric congenital airway abnormalities.

Child, Preschool↗
PubMed2004

[Fluoroscopy guided L5-S1 transforaminal injection as a treatement for s1 radiculopathy].

OBJECTIVE: To assess the efficacy of fluoroscopy guided L5-S1 transforaminal steroid injections for the treatment of S1 radiculopathy secondary to intervertebral disk disorder. METHOD: 41 patients were included: prospective study (20 patients) and retrospective study (21 patients). All patients suffered from S1 radiculopathy secondary to nerve root compression by intervertebral disk material, as demonstrated by lumbar spine CT. The patients underwent 2 fluoroscopy guided L5-S1 transforaminal injections of steroid (Hydrocotancyl 125 mg), at 8 days interval. RESULTS: 60% of patients showed significant improvement of their painful radiculopathy at day 8 (n:41), 60-67% at day 30 (n:41) and 67% at day 90 (n:18). CONCLUSION: Fluoroscopy guided L5-S1 transforaminal injection showed good efficacy in the treatment of S1 radiculopathy.

Adrenal Cortex Hormones↗
PubMed1984

Noninvasive diagnostic test choices for the evaluation of coronary artery disease in women: a multivariate comparison of cardiac fluoroscopy, exercise electrocardiography and exercise thallium myocardial perfusion scintigraphy.

Several diagnostic noninvasive tests to detect coronary and multivessel coronary disease are available for women. However, all are imperfect and it is not yet clear whether one particular test provides substantially more information than others. The aim of this study was to evaluate clinical findings, exercise electrocardiography, exercise thallium myocardial scintigraphy and cardiac fluoroscopy in 92 symptomatic women without previous infarction and determine which tests were most useful in determining the presence of coronary disease and its severity. Univariate analysis revealed two clinical, eight exercise electrocardiographic, seven myocardial scintigraphic and seven fluoroscopic variables predictive of coronary or multivessel disease with 70% or greater stenosis. The multivariate discriminant function analysis selected a reversible thallium defect, coronary calcification and character of chest pain syndrome (p less than 0.05) as the variables most predictive of presence or absence of coronary disease. The ranked order of variables most predictive of multivessel disease were cardiac fluoroscopy score, thallium score and extent of ST segment depression in 14 electrocardiographic leads. Each provided statistically significant information to the model. The estimate of predictive accuracy was 89% for coronary disease and 97% for multivessel coronary disease. The results suggest that cardiac fluoroscopy or thallium scintigraphy provide significantly more diagnostic information than exercise electrocardiography in women over a wide range of clinical patient subsets.

Adult↗
PubMed2000

Nasoenteric feeding tubes in critically ill patients (fluoroscopy versus blind).

Numerous complications have been encountered with small-bore nasoenteric feeding tubes, some potentially life threatening. Patients particularly at risk are those with anatomic abnormalities, debilitation, or neurologic impairment. Fluoroscopy has been reported to be a safe, efficacious modality for the placement of these tubes. Thirty critically ill patients were studied to assess caloric delivery, costs, and complications associated with both fluoroscopically and blindly placed feeding tubes. All patients had either a tracheostomy or an endotracheal tube. They were randomized to group A (fluoroscopy) or group B (blind). Caloric delivery was greater in group A patients on days 1 through 5, with statistically significant differences on days 1 through 4. The mean daily calories per patient over the study period was 1135 +/- 96 and 662 +/- 110 (mean +/- SEM) in groups A and B, respectively (P < 0.01). Costs were similar in both groups. The most frequent problems encountered were difficult insertion, tubes requiring replacement, and failure to intubate the duodenum. We conclude that critically ill patients intubated either endotracheally or with tracheostomy should have nasoenteric feeding tubes placed with the guidance of fluoroscopy.

Adolescent↗
PubMedDate not supplied

Value of CT fluoroscopy for percutaneous biopsy procedures.

PURPOSE: To assess the clinical impact of computed tomographic (CT) fluoroscopy (CTF) with regard to procedure time and success rate for CT image-guided biopsy procedures. MATERIALS AND METHODS: One hundred ninety consecutive patients referred to the same radiologist underwent biopsy procedures performed with use of a CT scanner equipped with fluoroscopic capabilities during a 15-month period. CTF procedures were performed predominantly by means of a continuous fluoroscopic technique, with typical exposure factors of 50 mA at 120 kV and a slice thickness of 10 mm. The total procedure time, fluoroscopy time, and complication and procedure success rates were documented prospectively in this group. A control group consisted of retrospective analysis of 93 consecutive patients who had undergone a classic CT-guided procedure performed by the same radiologist. RESULTS: Procedure success rate was increased in the CTF group (93.7 versus 88.2%), although the difference was not statistically significant (P > .05: Fisher exact test). A statistically significant difference was noted when comparing mean procedure times (CTF, 27.56 minutes; range, 20-60 minutes versus control, 43.17 minutes; range, 35-80 minutes; P < .0001; Welch unpaired t test). CONCLUSION: CT fluoroscopy facilitates CT-guided biopsy procedures by allowing visualization of the needle trajectory from skin entry to the target point, allowing procedures to be performed more rapidly and efficiently.

Adolescent↗
PubMed2002

Computed tomography fluoroscopy-guided chemical lumbar sympathectomy: simple, safe and effective.

Demographic, clinical and laboratory data were retrospectively collected from records of 146 cases of CT fluoroscopy-guided chemical lumbar sympathectomy for the palliation of inoperable peripheral vascular disease (PVD) between January 1997 and August 1999. Of these, 16% had claudication, 39% had rest pain and 44% had ischaemic ulcers or gangrene. Seventy-three percent of elective cases were outpatients. At 3 months, 27 cases were lost to follow up, leaving 119 cases. Within 3 months, improvement, defined as doubling of the walking distance, cessation of rest pain or healing of ulcers, occurred in 30.3% of cases. No change was observed in 45.4% of cases and 24.3% of cases deteriorated. Patients with ulcers or gangrene had significantly poorer results than those without any ischaemic lesions, as only 19% versus 39% of patients improved (P < 0.05). The presence of hypertension, diabetes mellitus, hyperlipidaemia and smoking had no value in predicting clinical outcome (P > 0.05). There were no major complications noted. CT fluoroscopy-guided chemical lumbar sympathectomy is safe and effective, with a complication rate of less than 1%, and efficacy of at least 30% measured within 3 months. It is a simple and minimally invasive procedure, easily performed on an outpatient basis. CT fluoroscopy-guided chemical lumbar sympathectomy should be considered for all patients in the early stages of inoperable PVD.

Adult↗
PubMed2006

Transient lower esophageal sphincter relaxations and reflux: mechanistic analysis using concurrent fluoroscopy and high-resolution manometry.

BACKGROUND & AIMS: The aim of this study was to perform a detailed analysis of the mechanics leading to esophagogastric junction (EGJ) opening during transient lower esophageal sphincter relaxations (tLESRs) using high-resolution manometry coupled with simultaneous fluoroscopy. METHODS: Six subjects without hiatus hernia had endoclips placed at the squamocolumnar junction and 10 cm proximal. A 36-channel solid-state manometric assembly was placed spanning from stomach to pharynx, and subjects were studied for 2 hours after a high-fat meal. An esophageal pH electrode also was placed and fluoroscopy was initiated at the onset of a tLESR. Axial clip movement was measured during replay of the videotaped fluoroscopy and was correlated with manometric data. RESULTS: Ninety-three tLESRs were recorded, 62 tLESRs of which had good fluoroscopic visualization. Seventy-eight tLESRs had manometric evidence of flow and the majority had evidence of a common cavity (88%), but few were detected by the pH electrode. Esophageal shortening and crural diaphragm inhibition always preceded EGJ opening and common cavity. A positive pressure gradient between the stomach and the EGJ lumen of 7.1 mm Hg (interquartile range, 4.1-9.1 mm Hg) preceded the EGJ opening. CONCLUSIONS: Key events leading to the EGJ opening during tLESRs were LES relaxation, crural diaphragm inhibition, esophageal shortening, and a positive pressure gradient between the stomach and the EGJ lumen. The manometric signature of opening was pressure equalization within the EGJ, but this only occasionally was associated with pH evidence of reflux. Future investigations will need to analyze how this delicately balanced anatomic-physiologic system is perturbed in subjects with reflux disease.

Adult↗