Prevalence of non-bronchial systemic culprit arteries in patients with hemoptysis with bronchiectasis and chronic pulmonary infection who underwent de novo bronchial artery embolization.

OBJECTIVES: To identify the prevalence of non-bronchial systemic culprit arteries and their relationship to bleeding lobes in patients with hemoptysis with bronchiectasis and chronic pulmonary infection who underwent de novo bronchial artery embolization (BAE). METHODS: Data of 83 consecutive patients with bronchiectasis and chronic pulmonary infection (non-tuberculous mycobacteriosis, aspergillosis, and tuberculosis) who underwent de novo BAE between January 2019 and December 2020 were retrospectively reviewed. The prevalence of culprit arteries was investigated. RESULTS: Fifty-five patients (66%) had 172 non-bronchial systemic culprit arteries. The bleeding lobes were the right upper, right middle, right lower, left upper, and left lower lobes in 14 (17%), 20 (24%), 7 (8%), 31 (37%), and 11 (13%) patients, respectively. The internal thoracic (49%; n = 41), intercostal (28%; n = 23), and inferior phrenic (28%; n = 23) arteries were the top three non-bronchial systemic culprit arteries, which were involved in all five types of bleeding lobes. The costocervical trunk and thoracoacromial and lateral thoracic arteries were predominant in patients with upper lobe bleeding. Ligament arteries were predominant in patients with left lower lobe bleeding. CONCLUSIONS: These findings will better ensure the identification of non-bronchial systemic culprit arteries in patients with hemoptysis with bronchiectasis and chronic pulmonary infection. All systemic arteries, especially those which are adjacent to the lung lesions, should be evaluated carefully using MDCT; the internal thoracic, intercostal, and inferior phrenic arteries should be proactively assessed using angiography. KEY POINTS: • Non-bronchial systemic culprit arteries were identified in 66% of patients with hemoptysis with bronchiectasis and chronic pulmonary infection who underwent de novo bronchial artery embolization. • The internal thoracic (49%), intercostal (28%), and inferior phrenic (28%) arteries were the top three arteries, which were involved in all five types of bleeding lobes. • The costocervical trunk and thoracoacromial and lateral thoracic arteries were prominent in patients with upper lobe bleeding, and the ligament artery was prominent in patients with left lower lobe bleeding.

Successful bronchial artery embolization using hydrogel coils for hemoptysis during extracorporeal membrane oxygenation.

A 58-year-old woman with bronchiectasis presented with massive hemoptysis and severe respiratory failure, which required long-term extracorporeal membrane oxygenation with continuous heparin infusion. Bronchial artery embolization using hydrogel coils, which provide a greater volume occlusion than bare platinum coils, was performed; hemoptysis stopped and she fully recovered. No recanalization was observed on follow-up computed tomography angiography 2 months postbronchial artery embolization, and there had been no recurrence of bleeding at the time of this report (at least 6 months). Although continuous anticoagulation during extracorporeal membrane oxygenation might hinder complete vessel occlusion by metallic coils or induce early recanalization (because the homeostatic mechanism of coils depends on the patient's coagulability), our experience showed that bronchial artery embolization using hydrogel coils was effective and safe. Additionally, this case presents a successful example of anticoagulation management for patients with hemoptysis on extracorporeal membrane oxygenation who undergo bronchial artery embolization using coils.

Electrical stimulation and virtual reality-guided balance training for managing paraplegia and trunk dysfunction due to spinal cord infarction.

A 41-year-old woman presented with spinal cord infarction and paraplegia after acute thoracoabdominal aortic dissection. Clinical evaluation revealed the American Spinal Injury Association (ASIA) lower limb exercise score of 0 points and the Functional Assessment for Control of Trunk (FACT) score of 0 points. Conventional physical therapy for 60 days did not significantly improve the paraplegia or FACT score; therefore, belt electrode skeletal muscle electrical stimulation (B-SES) and virtual reality (VR)-guided sitting balance training were introduced for 30 days. She developed independence for all basic movements and her gait was restored using short leg braces and Lofstrand crutches. At discharge, her ASIA lower limb exercise score was 24 and FACT score was 7, with a functional impedance measure motor item of 57, and she could continuously walk for a distance of 150 m. The combination of B-SES and VR-guided balance training may be a feasible therapeutic option after spinal cord infarction.

Bronchial Artery Aneurysm: Prevalence, Clinical Characteristics, and Long-Term Prognosis Following Bronchial Artery Embolization.

PURPOSE: To investigate the prevalence, clinical characteristics, and long-term prognosis of bronchial artery aneurysm (BAA) following bronchial artery embolization (BAE). MATERIALS AND METHODS: The medical records of consecutive patients who underwent bronchial artery angiography between August 2013 and December 2019 were retrospectively reviewed. Patients who were diagnosed with BAA during this period were included in this study. The prevalence, patients' characteristics, symptoms, comorbidities, angiographic findings, and long-term prognosis following BAE were investigated. RESULTS: BAA was observed in 20 of 508 patients who underwent bronchial artery angiography (3.9%). The patients' median age was 69 (interquartile range [IQR], 63.5-76.7) years. The main causes of BAA were cryptogenic, bronchiectasis or cystic fibrosis, and pulmonary aspergillosis. The median diameter of ruptured BAAs was significantly smaller than that of unruptured BAAs (5.4 mm [IQR, 4.8-7.3 mm] vs 9.0 mm [IQR, 7.2-13.9 mm], P = .009). All the patients were successfully treated with BAE, without major adverse events. The median follow-up period after BAE was 970 (IQR, 561-1,796) days. The BAA-related survival rate was 100% at 2 and 3 years after BAE, and the overall survival rate after BAE was 89.2% (95% confidence interval [CI] 89.0-89.3) at 2 years and 74.3% (95% CI 74.0-74.5) at 3 years. BAA-related adverse events and mortality did not occur during the follow-up period. CONCLUSIONS: BAA was observed in 3.9 % (20/508) of the patients who underwent bronchial artery angiography. All the patients with BAA were successfully treated with BAE. BAA rupture and consequent mortality did not occur during the follow-up period.

Case of cerebellar ataxia successfully treated by virtual reality-guided rehabilitation.

A male patient in his 40s was transferred to our hospital for rehabilitation of ataxia after right cerebellar and brainstem infarction. After 3 weeks of conventional physical therapy, his activities of daily life successfully improved with an increase in the functional impedance measure from 101 to 124. However, he still fell short of gaining a higher level of balance function, which was necessary for his job as a standup forklift driver. We introduced virtual reality-guided balance training. The training was performed for approximately 40 min on weekdays for 2 weeks. As a result, the Scale for the Assessment and Rating of Ataxia score decreased from 5 to 1, Functional Balance Scale score improved from 48 to 56, and Mini-Balance Evaluation Systems Test score increased from 20 to 28. The trunk sway disappeared clinically. He regained confidence and returned to work after an additional 2 weeks of physical therapy.

The impact of bronchial artery embolisation on the quality of life of patients with haemoptysis: a prospective observational study.

OBJECTIVES: Patients with haemoptysis often experience daily physical and mental impairment. Bronchial artery embolisation is among the first-line treatment options used worldwide; however, no evidence exists regarding the health-related quality of life (HRQoL) after bronchial artery embolisation. Therefore, this study aimed to evaluate the effects of bronchial artery embolisation on the HRQoL of patients with haemoptysis. METHODS: We prospectively enrolled 61 consecutive patients who visited our hospital from July 2017 to August 2018 and received bronchial artery embolisation for haemoptysis. The primary outcome was the HRQoL evaluated using the Short Form Health Survey, which contains physical and mental components, before and after bronchial artery embolisation. The secondary outcomes were procedural success, complications, and recurrence-free survival rate at 6 months. RESULTS: The mean age of the patients was 69 years (range, 31-87 years). The procedural success rate was 98%. No major complications occurred. The recurrence-free survival rate estimated using the Kaplan-Meier analysis at 6 months after bronchial artery embolisation was 91.8% (95% confidence interval, 91.1-92.5%). Compared with the pre-treatment scores, the physical and mental scores were significantly improved at 6 months after bronchial artery embolisation (p < 0.05). CONCLUSION: Bronchial artery embolisation improved the HRQoL of patients with haemoptysis. KEY POINTS: • Bronchial artery embolisation improved the HRQoL of patients with haemoptysis. • Vessel dilation on computed tomography and systemic artery-pulmonary artery direct shunting on angiography were the most common abnormalities. • The recurrence-free survival rate estimated using the Kaplan-Meier analysis at 6 months after bronchial artery embolisation was 91.8%.

Spinal Cord Infarction after Bronchial Artery Embolization for Hemoptysis: A Nationwide Observational Study in Japan.

Background The most serious complication of bronchial artery embolization (BAE) for hemoptysis is spinal cord infarction. However, because it is rare, previous reports from single institutions have been insufficient to determine the actual prevalence of spinal cord infarction after BAE. Purpose To investigate the actual prevalence of spinal cord infarction as a complication of BAE using a nationally representative inpatient database. Materials and Methods This retrospective study was performed using data from the Japanese Diagnosis Procedure Combination database between July 2010 and March 2018. The authors identified patients who were diagnosed with hemoptysis and underwent BAE during hospitalization. The overall prevalence of spinal cord infarction after BAE was determined. The authors also compared the prevalence of spinal cord infarction using the Fisher exact test according to the embolic agent used for BAE: coils, gelatin sponge (GS) particles, and N-butyl-2-cyanoacrylate (NBCA). Results During the study period, 8563 patients (mean age ± standard deviation, 68 years ± 13; 5103 men) met the inclusion criteria. Among these 8563 patients, 1577 (18%), 6561 (77%), and 425 (5%) underwent BAE with coils, GS particles, and NBCA, respectively. The overall prevalence of spinal cord infarction as a complication of BAE was 0.19% (16 of 8563 patients). The prevalence of spinal cord infarction after BAE with coils, GS particles, and NBCA was 0.06% (one of 1577 patients), 0.18% (12 of 6561 patients), and 0.71% (three of 425 patients), respectively (P = .04). Conclusion With use of a nationwide real-world inpatient database, the results of this study demonstrated that the actual prevalence of spinal cord infarction as a complication of bronchial artery embolization (BAE) for hemoptysis was 0.19%. Patients who underwent BAE with coils had a lower prevalence of spinal cord infarction than patients who underwent BAE with gelatin sponge particles or N-butyl-2-cyanoacrylate. © RSNA, 2021.

Erratic coil migration in the bronchus after bronchial artery embolization.

Herein, we report two cases of erratic coil migration from the bronchial artery to the bronchus after bronchial artery embolization (BAE). Neither patient exhibited haemoptysis recurrence, but chest radiographs revealed that part of the coil had disappeared. In Case 1, the patient coughed up the coil 4.5 years after BAE. We performed repeat BAE to minimize the possibility of haemoptysis considering bronchoscopic and angiographic findings. In Case 2, the patient had severe dry cough 2 years after BAE. Chest radiography showed migrated coils in the trachea; bronchoscopy revealed a migrated fragment of the coil protruding from the elevated mucosa. We used a loop cutter to split the coil and then removed it using forceps. Coil migration to the bronchus is an infrequent late-stage complication of super-selective bronchial artery coil embolization, and only one other case has been reported. Accordingly, we propose treatment strategies and speculate on the mechanism of fistula formation.

Virtual Reality-guided, Dual-task, Body Trunk Balance Training in the Sitting Position Improved Walking Ability without Improving Leg Strength.

BACKGROUND: Virtual reality (VR) technology has been recently introduced in a variety of clinical settings, such as physical, occupational, cognitive, and psychological rehabilitation or training. However, the clinical efficacy of VR rehabilitation compared with traditional training techniques remains to be elucidated. CASE: A 90-year-old man underwent VR-guided, dual-task, body trunk balance training in the sitting position using a newly developed medical device (mediVR KAGURA, mediVR, Inc., Toyonaka, Japan) after his physical activity level had plateaued. The patient had difficulty in walking outside the hospital even after having undergone traditional physical training. VR-guided training was performed for 40 min every weekday for 2 weeks. Trunk balance training was performed using reaching tasks, and cognitive stimulation was designed to emulate the cognitive processing involved when walking in a city or town. After the VR-guided training, the patient's 6-min walk distance improved from 430 m to 500 m even though there had been no improvement in muscle strength of the lower extremities. Furthermore, the patient could successfully walk outside the hospital without falling or colliding with obstacles. DISCUSSION: It is noteworthy that the patient's walking ability improved further by the addition of VR-guided, dual-task, trunk balance training carried out in the sitting position. This finding suggests several possible new approaches to overcoming walking disability. Walking requires lower-extremity muscle strength, postural balance, and dual-task processing. Currently, no effective quantitative methods have been identified for postural balance and dual-task training with the patient in the sitting position. Herein, we discuss the possible advantages of VR-guided rehabilitation over traditional training methods.

Mechanisms of recurrent haemoptysis after super-selective bronchial artery coil embolisation: a single-centre retrospective observational study.

OBJECTIVES: In recognition of the significant impairment caused by haemoptysis on a patient's quality of life, bronchial artery embolisation has been introduced worldwide as one of the first-line treatment options. Since little evidence is available on the mechanisms of recurrent haemoptysis after super-selective bronchial artery coil embolisation (ssBACE), the purpose of the present study is to evaluate these. METHODS: We retrospectively evaluated the mechanisms of recurrent haemoptysis using both enhanced computed tomography and cineangiography following ssBACE by reviewing 299 haemoptysis-related arteries (HRAs) in 57 consecutive patients who underwent 2nd series ssBACE for the management of recurrent haemoptysis between April 2010 and December 2015. RESULTS: Median age of patients was 69 (interquartile range 64-74) years, and 43.9% were men. This study revealed that (1) recanalisation was the most common mechanism (45.2%) followed by development of new HRA (38.5%), bridging collaterals (14.7%) and conventional collaterals (1.7%); (2) these trends could be modified in several situations such as with antiplatelet or anticoagulant medications; (3) relatively large-diameter HRAs were more likely to recanalise compared with small-diameter HRAs and (4) recurrent haemoptysis could be managed by 2nd series ssBACE with a procedural success rate of 97.7% without any major complications. CONCLUSIONS: Recanalisation was the most common mechanism of recurrent haemoptysis after ssBACE. Our results provide interventionists with indispensable insights. KEY POINTS: • Recanalisation was the most common mechanism of recurrent haemoptysis after super-selective bronchial artery coil embolisation, followed by development of new haemoptysis-related arteries • These trends could be modified in several situations such as with antiplatelet or anticoagulant medications • Recurrent haemoptysis could be managed by 2nd series super-selective bronchial artery coil embolisation with a procedural success rate of 97.7% without any major complications.

Efficacy and safety of super selective bronchial artery coil embolisation for haemoptysis: a single-centre retrospective observational study.

OBJECTIVES: Evidence on the safety and long-term efficacy of super selective bronchial artery embolisation (ssBAE) using platinum coils in patients with haemoptysis is insufficient. The objective of the present study was to evaluate the safety and the 3-year postprocedure haemoptysis-free survival rate of de novo elective ssBAE using platinum coils rather than particles for the treatment of haemoptysis. DESIGN: A single-centre retrospective observational study. SETTING: Hemoptysis and Pulmonary Circulation Center in Japan. PARTICIPANTS: A total of 489 consecutive patients with massive and non-massive haemoptysis who underwent de novo elective ssBAE without malignancy or haemodialysis. INTERVENTIONS: ssBAE using platinum coils. All patients underwent CT angiography before the procedure for identifying haemoptysis-related arteries (HRAs) and for procedural planning. PRIMARY AND SECONDARY OUTCOME MEASURES: The composite of the 3-year recurrence of haemoptysis and mortality from the day of the last ssBAE session. Each component of the primary end point and procedural success defined as successful embolisation of all target HRAs were also evaluated. RESULTS: The median patient age was 69 years, and 46.4% were men. The total number of target vessels was 4 (quartile 2-7), and the procedural success rate was 93.4%. There were 8 (1.6%) major complications: 1 aortic dissection, 2 symptomatic cerebellar infarctions and 5 mediastinal haematoma cases. The haemoptysis-free survival rates were estimated by the Kaplan-Meier analysis at 86.9% (95% CI 83.7% to 90.2%) at 1 year, 79.4% (74.8% to 84.3%) at 2 years and 57.6% (45.1% to 73.4%) at 3 years. Although not statistically significant by the adjusted analysis of variance with multiple imputation of missing variables, cryptogenic haemoptysis tended to show the most favourable outcome and non-tuberculous mycobacterium showed the worst outcome (adjusted p=0.250). CONCLUSIONS: We demonstrated the safety and long-term efficacy of elective ssBAE using platinum coils and established that it can be a valuable therapeutic option for treating patients with haemoptysis.

[A case of a 91-year-old patient with advanced squamous cell lung cancer complicated with renal dysfunction successfully treated with trans-arterial chemo-embolization].

In 2009, a 91-year-old man with renal dysfunction was detected with a small nodule in the left pulmonary field. The nodule was found to have gradually increased in size by April, 2010. A trans-bronchial lung biopsy(TBLB)and computed tomography( CT)revealed squamous cell lung cancer and stage IV (a tumor was found on the right side as well), respectively. Systemic chemotherapy was not administered because of the advanced age of the patient and mild renal dysfunction. We obtained informed consent from the patient and his family before trans-arterial chemo-embolization(TACE)was performed. No side effects were observed either during or after treatment. Although his visits to our hospital stopped, he sought treatment for a cold 8 months after TACE. CT showed 87% shrinkage of the tumor shadow. This method could be a new therapeutic option for non-small cell lung cancer with little side effects, particularly in older patients or those with pulmonary complications.

[Application of interlocking detachable coil (IDC) in superselective bronchial artery embolization].

Bronchial artery embolization (BAE) is almost the only effective nonsurgical treatment for massive hemoptysis. Metallic coils with plastic fibers are widely used as embolic materials. We have introduced an interlocking detachable coil (IDC) for BAE. IDC is a mechanically detachable coil, allowing the operator to seek the ideal shape until its final release. We compared hemoptysis patients treated with conventional metallic coils (24 patients, non-IDC group) with those treated with conventional coils and IDCs (26 patients, IDC group). The hemoptysis rate after three months is significantly lower in the IDC group than in the non-IDC group (7.7% vs. 16.3%, p = 0.035 Fisher's exact method). Total procedure time (in staged or repetitive BAE cases, procedure times are added together) is significantly shorter in the IDC group than in the non-IDC group (3.4 +/- 1.4 hours vs. 4.4 +/- 2.5 hours, p = 0.040 unpaired t-test). IDC is a useful device for BAE. This is the first-ever report documenting the usefulness of IDC for BAE.

Prevalence of ciliochoroidal effusion after prophylactic laser iridotomy.

PURPOSE: To study the prevalence of ciliochoroidal effusion (CE) after prophylactic laser iridotomy (LI). METHODS: An ultrasound biomicroscope (UBM) examination was performed before, 2, and 24 hours after LI to investigate the changes in supraciliary-choroidal space after LI in circumference of 38 eyes in 23 chronic primary angle-closure patients. Subjects were divided randomly into two groups based on LI settings: 21 eyes by argon laser (Ar-LI group) and argon combined with yttrium-aluminum-garnet (YAG) laser in 17 eyes (Ar-YAG-LI group). Ciliochoroidal effusion was observed predominantly in the inferior sector (12 of 12 eyes, 100%) and rare in nasal part of the eyes (4 of 12 eyes, 33%). Ciliochoroidal effusion appeared more often in the Ar-LI group (10 eyes, 52%) than in the Ar-YAG-LI group (2 eyes, 12%). All CE disappeared 7 days after by UBM observation. CONCLUSIONS: Subclinical CE observed by UBM frequently occurs after LI.

Gravity-regulated differential auxin transport from columella to lateral root cap cells.

Gravity-induced root curvature has long been considered to be regulated by differential distribution of the plant hormone auxin. However, the cells establishing these gradients, and the transport mechanisms involved, remain to be identified. Here, we describe a GFP-based auxin biosensor to monitor auxin during Arabidopsis root gravitropism at cellular resolution. We identify elevated auxin levels at the root apex in columella cells, the site of gravity perception, and an asymmetric auxin flux from these cells to the lateral root cap (LRC) and toward the elongation zone after gravistimulation. We differentiate between an efflux-dependent lateral auxin transport from columella to LRC cells, and an efflux- and influx-dependent basipetal transport from the LRC to the elongation zone. We further demonstrate that endogenous gravitropic auxin gradients develop even in the presence of an exogenous source of auxin. Live-cell auxin imaging provides unprecedented insights into gravity-regulated auxin flux at cellular resolution, and strongly suggests that this flux is a prerequisite for root gravitropism.

Species differences in ligand specificity of auxin-controlled elongation and auxin transport: comparing Zea and Vigna.

The plant hormone auxin affects cell elongation in both roots and shoots. In roots, the predominant action of auxin is to inhibit cell elongation while in shoots auxin, at normal physiological levels, stimulates elongation. The question of whether the primary receptor for auxin is the same in roots and shoots has not been resolved. In addition to its action on cell elongation in roots and shoots, auxin is transported in a polar fashion in both organs. Although auxin transport is well characterized in both roots and shoots, there is relatively little information on the connection, if any, between auxin transport and its action on elongation. In particular, it is not clear whether the protein mediating polar auxin movement is separate from the protein mediating auxin action on cell elongation or whether these two processes might be mediated by one and the same receptor. We examined the identity of the auxin growth receptor in roots and shoots by comparing the response of roots and shoots of the grass Zea mays L. and the legume Vigna mungo L. to indole-3-acetic acid, 2-naphthoxyacetic acid, 4,6-dichloroindoleacetic acid, and 4,7-dichloroindoleacetic acid. We also studied whether or not a single protein might mediate both auxin transport and auxin action by comparing the polar transport of indole-3-acetic acid and 2-naphthoxyacetic acid through segments from Vigna hypocotyls and maize coleoptiles. For all of the assays performed (root elongation, shoot elongation, and polar transport) the action and transport of the auxin derivatives was much greater in the dicots than in the grass species. The preservation of ligand specificity between roots and shoots and the parallels in ligand specificity between auxin transport and auxin action on growth are consistent with the hypothesis that the auxin receptor is the same in roots and shoots and that this protein may mediate auxin efflux as well as auxin action in both organ types.

Drug-induced pneumonitis: thin-section CT findings in 60 patients.

PURPOSE: To describe thin-section computed tomographic (CT) findings in patients with drug-induced pneumonitis, to compare these CT findings, and to correlate them with arterial oxygen tension level. MATERIALS AND METHODS: Thin-section CT scans obtained in 60 patients with drug-induced pneumonitis were evaluated retrospectively. The patients had 31 cases of antineoplastic agent-induced pneumonitis and 29 cases of nonneoplastic agent-induced pneumonitis (antibiotic agent, 20 cases; herbal medicine [sho-saiko-to], four cases; antirheumatic agent, three cases; phenytoin, one case; disodium cromoglycate, one case). CT scans were reviewed by two chest radiologists in consensus. Correlation between arterial oxygen tension level and the extent of disease at CT was available in 21 patients. These two factors were compared by using the Spearman rank correlation coefficient. RESULTS: The predominant findings in antineoplastic agent-induced pneumonitis were diffuse or multifocal ground-glass opacities with intralobular interstitial thickening. The predominant CT findings in antibiotic agent-induced pneumonitis were patchy ground-glass opacities with centrilobular opacities and interlobular septal lines. The predominant CT findings in herbal medicine-induced pneumonitis were diffuse ground-glass opacities with patchy consolidation. Interlobular septal lines and centrilobular opacities were observed more frequently in antibiotic agent-induced pneumonitis, and intralobular interstitial thickening was observed more frequently in antineoplastic agent-induced pneumonitis. A significant correlation was established between arterial oxygen tension level and extent of disease at CT (r = -0.84, P <.05). CONCLUSION: In addition to ground-glass opacities and interlobular septal lines, the most common thin-section CT findings were intralobular interstitial thickening, observed in antineoplastic agent-induced pneumonitis, and centrilobular opacities, observed in antibiotic-induced pneumonitis.

The kinetics of root gravitropism: dual motors and sensors.

The Cholodny-Went theory of tropisms has served as a framework for investigation of root gravitropism for nearly three quarters of a century. Recent investigations using modern techniques have generated findings consistent with the classical theory, including confirmation of asymmetrical distribution of polar auxin transport carriers, molecular evidence for auxin asymmetry following gravistimulation, and generation of auxin response mutants with predictable lesions in gravitropism. Other results indicate that the classical model is inadequate to account for key features of root gravitropism. Initiation of curvature, for example, occurs outside the region of most rapid elongation and is driven by differential acceleration rather than differential inhibition of elongation. The evidence indicates that there are two motors driving root gravitropism, one of which appears not to be auxin regulated. We have recently developed technology that is capable of maintaining a constant angle of gravistimulation at any selected target region of a root while continuously monitoring growth and curvature kinetics. This review elaborates on the advantages of this new technology for analyzing gravitropism and describes applications of the technology that reveal (1) the existence of at least two phases to gravitropic motor output, even under conditions of constant stimulus input and (2) the existence of gravity sensing outside of the root cap. We propose a revised model of root gravitropism including dual sensors and dual motors interacting to accomplish root gravitropism, with only one of the systems linked to the classical Cholodny-Went theory.