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Background: The presence of large thrombus burden in patients presenting with acute myocardial infarction (AMI) is common and associated with poor prognosis. This study aimed to describe the feasibility and safety of the novel 'mother-in-child' thrombectomy (MCT) technique in patients presenting with AMI and large thrombus burden undergoing percutaneous coronary intervention (PCI). Methods: We studied 13 patients presenting with AMI who underwent PCI with persistent large intracoronary thrombus after standard thrombectomy. The procedure was performed using a 5F 'Heartrail II-ST01' catheter (Terumo Medical) into a 6F guiding system. Angiographic assessment of thrombus burden and coronary flow was obtained at baseline, immediately after thrombectomy and at the end of the procedure. Results: The mean age was 55.9±13.0 years and involved mostly males (76.9%). All patients underwent PCI via radial approach. Following MCT Thrombolysis In Myocardial Infarction (TIMI) flow improved by 2 or more degrees in 11 patients (84.5%), while visible angiographic thrombus was reduced in 11 patients (84.5%). In the final angiogram, normal TIMI flow was restored in 11 patients (84.5%), with normal myocardial 'blush' in 7 patients (53.8%) and total clearance of a visible thrombus in 7 patients (53.8%). Overall, 6 patients received thrombectomy as 'stand-alone' procedure. All patients were discharged alive after a mean of 5.6±2 days. Conclusion: This initial report suggests that significant reduction in thrombus burden and improvement of the coronary flow can be safely achieved in patients presenting with AMI and large thrombus burden by using the novel MCT technique. [ABSTRACT FROM AUTHOR]

Coronary angiography (CA) is the gold standard for identifying the presence and extent of atherosclerotic coronary artery disease or dynamic stenosis of the arteries., Aim: Review of the literature and international clinical guidelines on the evidence of its indications in different clinical scenarios., Method: Qualitative study through a narrative review of the current indications of the technique, limitations, possible complications and contraindications., Results: Information on the different scenarios in which CA is requested is extensive, ranging from expert recommendations to evidence-based clinical guidelines that support its performance. Undoubtedly, technological advances have led to the understanding of coronary pathology with the contribution of complementary techniques that contribute not only to the diagnosis but also to its treatment. It is important to understand its potential complications in order not only to plan a procedure and avoid them, and not to subject patients to tests that will not contribute in their clinical context., Conclusions: Since the first CA, performed by Mason Sones in 1958, there has been an exponential growth in interventional cardiology, where CA has improved its technique generating more evidence in its indications.

Background: Balance disorders in older people cause falls, which can have serious functional and economic consequences. No existing scale relates fall risk to daily life situations. This study describes the development, psychometric properties and construct validity of the Balance in Daily Life (BDL) scale, comprising seven routine tasks including answering a phone, carrying a heavy bag, and sitting down and getting up from a chair., Methods: Frail patients aged 65 years or more were prospectively recruited from the geriatric rehabilitation department of a French university hospital. Inclusion criteria included autonomous walking over 20 m and modified Short Emergency Geriatric Assessment score 8-11. Patients with motor skills disorders and comprehension or major memory difficulties were excluded. Patients were assessed on Day 3 and Day 30 with the Balance in Daily Life scale, Timed Up and Go, one-leg stance time, sternal nudge and walking-while-talking tests. The scale was assessed for acceptability, quality, unidimensionality, internal consistency, reliability, temporal stability, responsiveness and construct validity., Results: 140 patients (83 ± 6 years) were recruited, of whom 139 were assessed at Day 0 and 133 at Day 30. Acceptability was satisfactory (134/139 patients completed the test), quality assessment showed a slight floor effect (6 % of patients with minimal score) and evaluation of item redundancy found no strong correlation (Spearman <0.7). Unidimensionality was verified (Loevinger H coefficient > 0.5 for all items except item 6 = 0.4728). Internal consistency was good (Cronbach alpha = 0.86). Reliability and temporal stability were excellent (ICC = 0.97 and ICC = 0.92). Responsiveness was verified by significant score change p < 0.0001 between Day 0 and Day 30 (decreased by 1 [0; 2] point), in line with other score changes. Construct validity revealed that the Balance in Daily Life scale was convergent with results of the timed up-and-go and one-leg stance time (p < 0.0001 for both) and tended to be higher for participants who had not fallen in the previous 6 months (p = 0.0528). The new questionnaire was divergent to sternal nudge tests (p = 0.0002) and not related to the walking-while-talking test (p = 0.5969)., Conclusion: The Balance in Daily Life scale has good psychometric properties for this population. Its simplicity and innovative nature mean that it can be applied in institutions while being easily modifiable to domestic settings. Study registration on clinicaltrials.gov: NCT0334382., Competing Interests: Declaration of competing interest The authors declare that they have no competing interest., (Copyright © 2024 CHU Nîmes. Published by Elsevier B.V. All rights reserved.)

In patients with symptomatic severe aortic stenosis (SAS), who are at high surgical risk and who require transcatheter aortic valve implantation (TAVI), anatomic factors can determine if patients are suitable for this technique. A very large aortic annulus is a technical challenge given the limited options of adequate valve sizes, and, in most of them, using them in this type of patient is an off-label indication. We present the case of a 59-year-old man with symptomatic ASOS with surgical risk secondary to chronic liver damage referred for TAVI with an aortic annulus greater than 900 mm2. A Myval #32 valve was implanted with overexpansion without complications and early discharge.

Tricuspid regurgitation (TR) is the most frequent valvular complication after heart transplantation with different clinical sequelae. In its most severe form, it can cause right heart failure with a poor long-term prognosis. Its management is complex, both medical, surgical, and percutaneous. The TricValve system, a bicaval system with two self-expanding valves (superior vena cava and inferior vena cava), dedicated to treating symptomatic IT refractory to medical therapy, is safe and effective in improving quality of life. We present the first heart transplant patient with severe symptomatic TR who underwent successful bicaval valve (TricValve) implantation.

Syncope is a frequent consult. It's responsible for 1 to 3% of consults to the emergency room in the United States. The cause is generally benign; however, high-risk cases are potentially deadly and must be identified. We present a case report of a 40-year-old female who presents with syncope, Torsade de Pointes, and ventricular fibrillation. The coronary angiography showed no disease of the coronary arteries. The ventriculography, transthoracic echocardiogram, and cardiac magnetic resonance revealed a mid-ventricular Takotsubo cardiomyopathy. The ECG showed a prolonged QT interval with an inverted T wave. During the first 48 hours, she presented multiple episodes of non-sustained polymorphic ventricular tachycardia. The patient evolved with diminished QTc interval and regression of the wall motion abnormalities. At the 6-month follow-up the patient was asymptomatic, without new episodes.

Chest pain is one of the most frequent reasons for consultation in the emergency department. The most severe pathologies must be quickly ruled out within the diagnostic hypotheses: myocardial infarction (MI), aortic dissection, pulmonary thromboembolism, and pneumothorax. A frequent scenario is ST elevation MI due to a plaque accident. However, there are infrequent cases of aortic dissection associated with a deficit in coronary perfusion (malperfusion syndrome) that triggers a MI. The diagnosis of a double artery is difficult, with higher mortality and surgical complexity. We present the case of a 59-year-old man who presented chest pain and an electrocardiogram with inferior and anterior ST-segment elevation who was referred for primary angioplasty. The angiographic study confirmed the presence of a coronary ostium defect and suggested aortic dissection. Computed tomography angiography confirmed the diagnosis, showing the dissection of the ascending aorta with the compromise of both coronary ostia, which was subjected to surgical treatment.

Endomyocardial biopsy (EMB) is an invasive procedure and a diagnostic tool used mainly on the follow-up of post-heart transplant rejection in the past years. Currently, it has an important role in the diagnosis of non-ischemic cardiomyopathies. EMB is frequently performed through a venous access to enter the right ventricle. Diagnostic performance has improved with advances in pathology analysis. Its complications risk, close to 1% in high-volume interventional centers, can be justified considering the potential benefit of an accurate diagnosis and prognosis.

Chronic coronary syndromes are usually considered uncommon in young women, related to slower progression of atherosclerotic coronary artery disease, have atypical clinical presentations, and experience less diagnostic investigation. Non-atherosclerotic causes of coronary artery disease should be considered in young women experiencing angina. We report a 25-year-old woman who consulted for five months of moderate exertion angina. Physical examination revealed a right carotid bruit and asymmetrical upper extremity peripheral pulses. Initial work-up and imaging allowed to diagnose aortitis with bilateral coronary ostial stenosis secondary to Takayasu's arteritis. The patient experienced an apparent clinical response to initial medical therapy. However, follow-up evaluation revealed persistence of significant ischemia and requirement for myocardial revascularization. A percutaneous coronary intervention was performed.

Background The coronavirus disease (COVID-19) pandemic affected the prompt diagnosis and treatment of Acute myocardial infarction (AMI)., Aim: To characterize the clinical profile of patients with AMI during the COVID-19 pandemic, comparing them with a historical cohort., Material and Methods: A case-control study of 96 patients with AMI transferred to a high-volume percutaneous coronary intervention (PCI) hospital between March and July 2020, and a historical cohort of 269 patients transferred during the same period in 2019., Results: When comparing patients transferred during the pandemic with those of the historical cohort, the former were younger (63 ± 12 vs 68 ± 12 years, p < 0.01), had a higher frequency of hypertension (66 vs 45%, p < 0.01) and of smoking (40% vs 25%, p < 0.01). Also, during COVID-19 outbreak a higher proportion of patients had ST-elevation AMI consulting > 12 hours from the onset of symptoms (44 vs 0%, p < 0.01), a higher median door-to-device time (4 vs 3 hours, p < 0.01), a higher use of primary percutaneous coronary intervention (97 vs 71%, p < 0.01), and higher frequencies of cardiogenic shock (20 vs 4%, p < 0.01) and mechanical complications (10% vs 2%, p < 0.01). Patients during COVID pandemic had a higher thirty-day overall (20 vs 1.4%, p < 0.01) and cardiovascular mortality (13 vs 1%, p < 0.01). During the outbreak, 40% of patients had positive COVID-19 status, which was a predictor for thirty-day overall mortality (Risk ratio 2.90; 95% confidence intervals 1.14-7.36)., Conclusions: During the pandemic patients with AMI exhibited delays in consultations and treatment, higher morbidity, and increased mortality. COVID-19 positivity was associated to worse thirty-day overall survival.

The coronary artery aneurysm (CAA) is not a frequent condition in the catheterization laboratory. The management is uncertain. Most of the cases, the treatment is surgical with good results. In smaller aneurysm, the use of covered stents is an alternative. This is an anterograde approach CTO (chronic total occlusion) case of a middle segment RCA (right coronary artery) with a thrombosed coronary aneurysm. This was occluded due to thrombus as a result of a STEMI five months ago. In this case, we used a covered stent with good results in follow up to five months., Competing Interests: Declaration of Competing Interest There is not conflict of interest of the authors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Cardiogenic shock (CS) is uncommon in the cardiac catheterization laboratory (CCL) among patients undergoing coronary angiography. Periprocedural CS is more frequent in high-risk patients and in technically demanding procedures., Aim: To describe the clinical outcomes of patients who underwent peripheral venoarterial extracorporeal membrane oxygenation (pVA-ECMO) for CS associated with interventional cardiology procedures., Material and Methods: Review of clinical records of seven patients treated between January 2014 and October 2018., Results: pVA-ECMO was implanted within 6 hours of the interventional cardiology procedure. All patients had coronary artery disease and one of them also had symptomatic severe aortic stenosis. One patient entered the CCL in cardiac arrest. Percutaneous coronary intervention (PCI) was performed in all patients; four patients underwent an emergency procedure and five patients experienced PCI complications. One patient undergoing transcatheter aortic valve replacement suffered acute severe aortic regurgitation. An intra-aortic balloon pump was inserted at the CCL in five patients. Six patients experienced cardiac arrest. Mean SAVE score was -4.3 and baseline lactate 55 mg/dl. pVA-ECMO mean duration was 5 ± 4 days. Survival after both hospital discharge and 12 months of follow-up was 85.7% Regarding vascular access complications, we observed one access site hematoma and one episode of cannulation site bleeding requiring surgical repair., Conclusions: pVA-ECMO should be considered in patients with periprocedural CS as a bridge to recovery. Its use was associated with improved clinical outcomes in this series.

Background: Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is common. Cardiac magnetic resonance (CMR) and intravascular imaging (IVI) may be useful for establishing its etiology., Aim: To describe a population with MINOCA and its multi-image assessment using IVI or CMR., Material and Methods: Review of medical records, imaging and functional studies of patients with MINOCA treated in three different clinical centers between 2015 and 2019., Results: Twenty-eight patients with MINOCA and IVI were included. Seventy eight percent were women, 46% had hypertension, 32% smoked and 32% had dyslipidemia. At wall motion assessment, 46% presented apical ballooning pattern. In 36% of patients IVI identified lesions that explained the cause of MINOCA, namely plaque disruption (PD) in 18%, spontaneous coronary dissection in 11% and a thrombus without PD in 7%. Forty-six percent of patients had uncomplicated atherosclerotic plaques, and 36% had no pathological findings. CMR was performed in 50% of patients, identifying in all a diagnostic pattern. In nine cases it was compatible with stress cardiomyopathy, three cases had a myocarditis and two cases had transmural infarctions. PD and transmural late gadolinium enhancement were observed in 23% of patients with apical ballooning. Patients with a pattern of myocarditis did not have acute pathological findings at IVI. After a mean follow-up of 16.4±11.4 months, 3 patients with PD died., Conclusions: Among patients with MINOCA, there was a predominance of female gender with low cardiovascular risk factor load. The multi-image assessment allowed greater precision for etiological diagnosis of MINOCA. Apical ballooning was not pathognomonic for stress cardiomyopathy. PD was associated with mortality.

Objectives: To evaluate the adherence, usability and acceptance of a rehabilitation protocol with a music-based serious game (SG) and its effect on rhythmic skills in Parkinson disease (PD)., Methods: Sixteen PD patients with mild cognitive and motor impairments were included (mean [SD] age 65 [7.28] years and Hoehn & Yahr score 2-3). Rehabilitation consisted of a 6-week at-home training program targeting rhythmic skills with a dedicated SG, Rhythm Workers, implemented on a tablet device. Patients were asked to play the game at least 30min, 3 times a week. Two half-day evaluations were conducted before and after rehabilitation. Time played and average game scores were recorded. Suitability was evaluated by a questionnaire inspired by the Suitability Evaluation Questionnaire (SEQ) and rhythmic skills by the Beat Alignment Test from the Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA)., Results: Patients played a mean (SD) of 313 (243) min, namely 57.9% of the expected time; the mean game score was 48.8/100 (19.5). The mean SEQ score for 12 patients was 29.2/45 (8.2); suitability was good to excellent for 10 patients. Beat perception reflecting rhythmic skills improved significantly in all but 5 patients., Conclusion: This study showed good to excellent suitability of an SG used on a tablet interface for rhythmic training in PD and the feasibility of this type of training in this population., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objective: The aim of this registry was to evaluate a new device designed to facilitate antegrade guidewire re-entry into the true lumen of a chronic total coronary occlusion (CTO) from the adjacent subintimal space., Background: Successful recanalization of CTOs results in clinical improvement in appropriately selected patients. CTO intervention is time- and resource-consuming, and a simplified approach enabling antegrade guidewire re-entry into the distal true lumen might improve success., Methods: Patients with CTO and ischemia were entered into a prospective registry regardless of lesion characteristics. If wire manipulation resulted in subintimal wire entrapment, a new re-entry tool (a 2.5-mm flat subintimal balloon with two exit ports offset by 180°) was used as a platform to attempt guidewire penetration into the distal true lumen. The primary endpoint assessed was successful device-guided re-entry. Standard techniques were then utilized to open the CTO., Results: In 40 consecutive CTO lesions attempted, 19 resulted in subintimal wire entrapment (mean occlusion length 44 mm). Sixteen of these 19 were successfully crossed with an antegrade guidewire into the distal true lumen using the new device (84%). One patient with unsuccessful re-entry was subsequently recanalized with a retrograde technique. All crossed lesions were stented (17/17), resulting in TIMI 3 flow without major complications. Two cases were unsuccessful. One patient had a grade I coronary perforation requiring no treatment., Conclusions: A new device to recanalize CTOs complicated by subintimal wire entrapment can be used successfully by experienced operators. Further study of this coronary re-entry device is ongoing., (Copyright © 2011 Wiley Periodicals, Inc.)

Taste and sensory information are closely associated and our electrophysiological studies showed a trigeminal modulation of gustatory neurons in the nucleus of the solitary tract (NST). Chorda tympani (CT) and lingual nerves (LN) converge centrally in the rostral subdivision of the NST in hamsters and rats. However, no study has yet revealed the details of this overlap on a same section. We therefore used a double-label strategy to visualize neurons in the NST that receive both trigeminal and gustatory inputs. An anterograde tracer (BDA, Biotinylated Dextran Amine) was applied unilaterally to the cut central end of the LN in male Sprague-Dawley rats. One week later, the ipsilateral CT was electrically stimulated, after which animals were perfused and brainstem sections double-labelled for Fos immunoreactivity of activated NST neurons and BDA labelling of LN afferents. Our results permitted to circumscribe the regional overlap of the trigeminal and CT afferents mainly in the rostral central (RC) subdivision of the gustatory NST. Fos-immunoreactive neurons were observed to be closely apposed by BDA-labelled fibres and terminal boutons. Such varicosities mainly "en passant" were especially present in the RC zone of the nucleus. These observations provide an anatomical substrate for trigemino-gustatory interactions.

We report a 79 year-old mate with a history of an acute coronary syndrome subjected to coronary angioplasty and stent placement in the right coronary artery (RCA) four months ago. Since the patient continued with symptoms, a coronary angiography was performed. During the procedure, the patient developed a cutaneous allergic reaction and bronchospasm probably related to contrast media and a severe spasm of the RCA with inferior ST elevation in the absence of restenosis, that was difficult to treat. The presence of angina or an acute coronary syndrome and allergic reactions is known as the Kounis syndrome.

To investigate the involvement of the noradrenergic locus coeruleus (LC) in the reflex blink circuit, c-Fos and neuronal tracer experiments were performed in the rat. LC neurons involved in reflex blink were localized by analyzing c-Fos protein expression after electrical stimulation of the supraorbital nerve. Subsequently, neuronal tracers were injected in two different nuclei which are part of the reflex blink circuit. Anterograde tracer experiments in the sensory trigeminal complex (STC) explored the trigemino-coerulear connection; retrograde tracer experiments in the latero-caudal portion of the superior colliculus (SC) established coerulear-collicular connections. The combination of retrograde tracer injections into the latero-caudal SC portion combined with electrical stimulation of the supraorbital nerve identified c-Fos positive LC neurons that project to the latero-caudal SC. Our results revealed the existence of a STC-LC-SC loop.

To characterize the organization and plasticity of the trigeminal reflex blink circuit, we interacted blink-evoking supraorbital (SO) and infraorbital (IO) nerve stimuli in alert rats. Stimulation of either trigeminal branch produced a short-lasting inhibition followed by a longer-lasting facilitation of blinks evoked by stimulating the other nerve. When IO stimulation evoked a smaller blink than SO stimulation (IO < SO), SO stimulation facilitated subsequent IO-evoked blinks more than IO stimulation facilitated SO-evoked blinks. When IO > SO, IO and SO stimulation exerted equivalent facilitation of subsequent reflex blinks. To investigate whether the blink circuit obeyed rules analogous to those governing the associative and spike timing-dependent plasticity exhibited by individual synapses, we compared the effects of 3600 simultaneous IO and SO pairings, asynchronous IO and SO pairings, or synchronous IO and SO pairings separated by 20 ms on temporal interactions between IO and SO inputs to the blink circuit. Simultaneous pairing of a weak IO and a strong SO strengthened the IO input to the blink circuit, whereas asynchronous pairing weakened the stronger input. When the pairing pattern made an afferent input arrive after blink circuit activity, it weakened that afferent input. Analogous to synaptic modifiability, the results revealed that blink-evoking stimuli acted as a "presynaptic input" and blink circuit activity acted as a "postsynaptic spike." These mechanisms may create the maladaptive reorganization of trigeminal inputs in diseases such as hemifacial spasm.

To determine the influence of the superior colliculus (SC) in orienting behaviors, we examined SC projections to the sensory trigeminal complex, the juxtatrigeminal region, and the facial motor nucleus in rats. Anterograde tracer experiments in the SC demonstrated predominantly contralateral colliculotrigeminal projections. Microinjections in the deep layers of the lateral portion showed labeled nerve fibers and terminals in the ventromedial parts of the caudal principal nucleus and of the rostral oral subnucleus and in the medial part of the interpolar subnucleus. Some terminals were also observed in the juxtatrigeminal region and in the dorsolateral part of the facial motor nucleus contralaterally, overlying the orbicularis oculi motoneuronal region. Verification by retrograde tracer injections into the trigeminal target regions showed labeled SC neurons mostly in lateral portions of layers 4-7. When the juxtatrigeminal region was involved, a remarkable increase of labeled neurons was observed, having a patch-like arrangement with a decreasing gradient from lateral to medial SC portions. Retrograde tracer injections in the dorsolateral VII nucleus showed bilateral labeled neurons mainly in the deep lateral SC portion. Retrograde BDA microinjections into the same trigeminal or juxtatrigeminal regions, followed by gold-HRP into the dorsolateral VII nucleus, demonstrated a significant number of SC neurons in deep layers 6-7 projecting to both structures by axon collaterals. These neurons are mediolaterally grouped in patches along the rostrocaudal SC extent; a subset of them are immunoreactive for glutamic acid decarboxylase (GAD). They could be involved in the coordination of facial movements. Simultaneous anterograde and retrograde tracer injections into the lateral SC portion and the VII nucleus respectively localized trigeminofacial neurons receiving collicular input in the trigeminal principal nucleus and pars oralis. Therefore the SC should play a crucial role in regulating motor programs of both eye and eyelid movements., (Copyright 2004 Wiley-Liss, Inc.)

Electrical stimulation of the supraorbital nerve (SO) induces eyelid closure by activation of orbicularis oculi muscle motoneurons located in the facial motor nucleus (VII). Neurons involved in brainstem central pathways implicated in rat blink reflex were localized by analyzing c-Fos protein expression after SO stimulation in conjunction with tracing experiments. A retrograde tracer (gold-horseradish peroxidase [HRP]) was injected into the VII. The distribution patterns of activated c-Fos-immunoreactive neurons and of neurons exhibiting both c-Fos immunoreactivity and gold-HRP labeling were determined in the sensory trigeminal complex (STC), the cervical spinal cord (C1), and the pontomedullary reticular formation. Within the STC, c-Fos immunoreactivity labeled neurons in the ipsilateral ventral part of the principal nucleus, the pars oralis and interpolaris, and bilaterally in the pars caudalis. Colocalization of gold-HRP and c-Fos immunoreactivity was observed in neurons of ventral pars caudalis layers I-IV and ventral pars interpolaris. In C1, SO stimulation revealed c-Fos neurons in laminae I-V. After additional injections in VII, the double-labeled c-Fos/gold-HRP neurons were concentrated in laminae IV and V. Although c-Fos neurons were found throughout the pontomedullary reticular formation, most appeared rostrally around the motor trigeminal nucleus and in the ventral parvocellular reticular nucleus medial to the fiber bundles of the seventh nerve. Caudally, c-Fos neurons were in the lateral portion of the dorsal medullary reticular field. In addition, these reticular areas contained double-labeled neurons in electrically stimulated rats that had received gold-HRP injections in the VII. The presence of double-labeled neurons in the STC, C1, and the reticular formation implies that these neurons receive sensory information from eyelids and project to the VII. These double-labeled neurons could then be involved in di- or trisynaptic pathways contributing to the blink reflex., (Copyright 2003 Wiley-Liss, Inc.)

Anterograde tracer injections in the rat sensory trigeminal complex are shown here to demonstrate projections to the contralateral facial motor (VII) and accessory abducens (VIacc) nuclei. Most of the trigeminal fibres originated within the pars oralis (5o) and contacted neurones in the medial and intermediate VII. Moderate projections from the pars caudalis (5c) and interpolaris (5i) reached the lateral and dorsolateral VII. Rare projections from the principal nucleus (5P) were found. Trigeminal projections to the contralateral VIacc originated mainly from the 5P and 5o. Few projections from the 5i and 5c to the contralateral VIacc were found. Retrograde tracer injections in the VII showed premotor neurones to the contralateral VII scattered throughout the 5o and in the ventromedial portion of the caudal 5i and the 5c. Double retrograde tracing experiments provide evidence that neurones in the 5o and 5c project to both the ipsi- and contralateral VII. Such collateralization would play a significant role in the co-ordination of the musculature of the face., (Copyright 2002 Elsevier Science Ireland Ltd.)

The distribution of premotor neurons projecting to motor nuclei of both the VIIth (VII) and XIIth (XII) nerves was examined in the pontomedullary reticular formation (RF) of the rat by using retrograde double labeling. After injection of two different tracers in the VII and the XII, most of the double labeled neurons were found caudally in the dorsal RF whereas rostrally they were located in the ventral RF. In some experiments, additional injections of an anterograde tracer were made in the sensory trigeminal nuclei. Anterogradely labeled trigeminal boutons were found in contact with retrogradely double labeled neurons throughout the pontomedullary RF. These neurons were mainly encountered ventral to the trigeminal motor nucleus and dorsal to the VII. Functionally, this region is known to be involved in eye protection mechanisms.

This study was undertaken to identify premotor neurons in the pontomedullary reticular formation serving as relay neurons between the sensory trigeminal complex and the motor nuclei of the VIIth and XIIth nerves. Trigeminoreticular projections were first investigated after injections of anterogradely transported tracers (biotinylated dextran amine, biocytin) into single subdivisions of the sensory trigeminal complex. The results show that the trigeminoreticular projections were abundant from the pars interpolaris (5i) and caudalis (5c) and moderate from pars oralis (5o) of the spinal trigeminal nucleus. Injections into the 5i and 5c produce dense anterograde labeling (1) in the dorsal medullary reticular field; (2) in the parvocellular reticular field, medially adjacent to the 5i; and (3) more rostral in the region dorsal and lateral to the superior olivary nucleus. Some labeled terminals were also found in the intermediate reticular field, whereas only light anterograde labeling was observed in the gigantocellular and oral pontine reticular formation. The 5o sends fibers and terminals throughout the whole reticular formation, with no clear preferential projections within a particular field. Only light projections originated from the principal nucleus (5P). In a second series of experiments, we examined whether premotor neurons in the reticular formation are afferented by trigeminal fibers. Double labeling was performed by injection of an anterograde tracer in the 5i and 5c and retrograde tracer (gold-horseradish peroxidase complex) into the VII or the XII motor nucleus on the same side. Retrogradely labeled neurons in contact with anterogradely labeled boutons were found throughout the reticular formation with predominance in the parvocellular and intermediate reticular fields. These experiments demonstrate the existence of trigeminal disynaptic influences, via reticular neurons of the pontomedullary reticular formation, in the control of orofacial motor behaviors., (Copyright 2001 Wiley-Liss, Inc.)