RÉSUMÉ
BACKGROUND: Bilateral diaphragmatic dysfunction can lead to dyspnea and recurrent respiratory failure. In rare cases, it may result from high cervical spinal cord ischemia (SCI) due to anterior spinal artery syndrome (ASAS). We present a case of a patient experiencing persistent isolated diaphragmatic paralysis after SCI at level C3/C4 following thoracic endovascular aortic repair (TEVAR) for Kommerell's diverticulum. This is, to our knowledge, the first documented instance of a patient fully recovering from tetraplegia due to SCI while still exhibiting ongoing bilateral diaphragmatic paralysis. CASE PRESENTATION: The patient, a 67-year-old male, presented to the Vascular Surgery Department for surgical treatment of symptomatic Kommerell's diverticulum in an aberrant right subclavian artery. After successful surgery in two stages, the patient presented with respiratory insufficiency and flaccid tetraparesis consistent with anterior spinal artery syndrome with maintained sensibility of all extremities. A computerized tomography scan (CT) revealed a high-grade origin stenosis of the left vertebral artery, which was treated by angioplasty and balloon-expandable stenting. Consecutively, the tetraparesis immediately resolved, but weaning remained unsuccessful requiring tracheostomy. Abdominal ultrasound revealed a residual bilateral diaphragmatic paralysis. A repeated magnetic resonance imaging (MRI) 14 days after vertebral artery angioplasty confirmed SCI at level C3/C4. The patient was transferred to a pulmonary clinic with weaning center for further recovery. CONCLUSIONS: This novel case highlights the need to consider diaphragmatic paralysis due to SCI as a cause of respiratory failure in patients following aortic surgery. Diaphragmatic paralysis may remain as an isolated residual in these patients.
Sujet(s)
Paralysie des muscles respiratoires , Ischémie de la moelle épinière , Humains , Mâle , Sujet âgé , Ischémie de la moelle épinière/étiologie , Paralysie des muscles respiratoires/étiologie , Paralysie des muscles respiratoires/chirurgie , Complications postopératoires/étiologie , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Artère subclavière/malformations , Sevrage de la ventilation mécanique , Vertèbres cervicales/chirurgie , Aorte thoracique/chirurgie , Malformations cardiovasculairesRÉSUMÉ
The combination of the right aortic arch and aberrant left subclavian artery (ALSA) with Kommerell's diverticulum (KD) is rare to coexist with the left innominate vein (LINV) beneath the aortic arch. It escalates the surgical risk undoubtedly and increases the difficulty of clinical procedures. We report one case diagnosed by Ultrasound and Computed Tomography Angiography (CTA).
Sujet(s)
Aorte thoracique , Veines brachiocéphaliques , Diverticule , Artère subclavière , Humains , Aorte thoracique/imagerie diagnostique , Aorte thoracique/malformations , Diverticule/imagerie diagnostique , Diverticule/complications , Veines brachiocéphaliques/malformations , Veines brachiocéphaliques/imagerie diagnostique , Artère subclavière/malformations , Artère subclavière/imagerie diagnostique , Angiographie par tomodensitométrie/méthodes , Mâle , Femelle , Échocardiographie/méthodes , Malformations multiples , Anévrysme/complications , Anévrysme/imagerie diagnostique , Malformations cardiovasculaires/complications , Malformations cardiovasculaires/imagerie diagnostiqueRÉSUMÉ
Coexistence of pulmonary embolism (PE) and arterial thrombosis in a single patient is rare. Management of such cases is challenging because there is no unified standard on how to treat this type of disease. We herein report a case involving a 73-year-old man who was admitted to the hospital because of a 2-day history of chest tightness. Pulmonary computed tomography angiography revealed a filling defect of the main pulmonary artery and bilateral branches as well as a left subclavian artery embolism. AngioJet mechanical thrombectomy (Boston Scientific, Marlborough, MA, USA) was used to treat the PE, and this was combined with left brachial artery incision and thrombectomy for treatment of the left subclavian artery embolism. The patient recovered well after the operation. The prognosis was good after 9 months of regular follow-up. AngioJet mechanical thrombectomy combined with left brachial artery incision thrombectomy may be a feasible treatment option for cases of PE combined with left subclavian artery embolism.
Sujet(s)
Embolie pulmonaire , Artère subclavière , Thrombectomie , Humains , Mâle , Sujet âgé , Embolie pulmonaire/chirurgie , Embolie pulmonaire/complications , Thrombectomie/méthodes , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Angiographie par tomodensitométrie , Résultat thérapeutique , Embolie/chirurgie , Embolie/complications , Embolie/étiologieRÉSUMÉ
OBJECTIVE: This study aimed to validate the efficiency of Doppler ultrasonography for predicting the innominate, subclavian, and common carotid artery stenosis. METHODS: This retrospective multicenter study between 2013 and 2022 enrolled 636 patients who underwent carotid Doppler ultrasonography and subsequent digital subtraction angiography. And 58 innominate artery stenosis, 147 common carotid artery stenosis, and 154 subclavian artery stenosis were included. The peak systolic velocity at innominate, subclavian, and common carotid artery, and velocity ratios of innominate artery to common carotid artery, innominate artery to subclavian artery, and common carotid artery to internal carotid artery were measured or calculated. The threshold values were determined using receiver operating characteristic analysis. RESULTS: The threshold values of innominate artery stenosis were peak systolic velocity >206 cm/s (sensitivity: 82.8%; specificity: 91.4%) to predict ≥50% stenosis and >285 cm/s (sensitivity: 89.2%; specificity: 94.9%) to predict ≥70% stenosis. The threshold values of common carotid artery stenosis were peak systolic velocity >175 cm/s (sensitivity: 78.2%; specificity: 91.9%) to predict ≥50% stenosis and >255 cm/s (sensitivity: 87.1%; specificity: 87.2%) to predict ≥70% stenosis. The threshold values of subclavian artery stenosis were peak systolic velocity >200 cm/s (sensitivity: 68.2%; specificity: 84.4%) to predict ≥50% stenosis and >305 cm/s (sensitivity: 57.9%; specificity: 91.4%) to predict ≥70% stenosis. CONCLUSIONS: Symptomatic patients with ultrasonic parameters of velocity at innominate artery ≥206 cm/s, velocity at common carotid artery ≥175 cm/s, or velocity at subclavian artery ≥200 cm/s need to be considered for further verification and whether revascularization is necessary.
Sujet(s)
Tronc brachiocéphalique , Artère carotide commune , Sténose carotidienne , Sensibilité et spécificité , Artère subclavière , Échographie-doppler couleur , Humains , Femelle , Mâle , Études rétrospectives , Tronc brachiocéphalique/imagerie diagnostique , Sténose carotidienne/imagerie diagnostique , Sténose carotidienne/physiopathologie , Artère subclavière/imagerie diagnostique , Artère subclavière/physiopathologie , Adulte d'âge moyen , Sujet âgé , Artère carotide commune/imagerie diagnostique , Artère carotide commune/physiopathologie , Échographie-doppler couleur/méthodes , Reproductibilité des résultatsRÉSUMÉ
INTRODUCTION: We describe a first case of human congenital crico-thyroid dysplasia associated to a right sided aortic arch and an aberrant subclavian artery. CASE PRESENTATION: Our patient presented with a two-weeks history of acute dyspnea, and reported hoarseness since his childhood. An urgent tracheotomy was performed, followed by direct laryngoscopy. Endoscopic examination showed a deviation of the dorsoventral axis of the larynx, with an obstructive submucosal swelling the area of the right false cord and aryepiglottic fold. Computed tomography conducted the following day confirmed the crico-thyroid dysplasia, an infected laryngocele, and the presence of a right sided aortic arch and an aberrant subclavian artery. CONCLUSION: The embryological basis of these anomalies is attributed to congenital defects of the development of the fourth and sixth pharyngeal arches. To our knowledge, the congenital crico-thyroid dysplasia has not been previously reported in human. This case underscores the importance of recognizing anatomical variations in laryngeal cartilages, understanding their embryological origins, and potential associated malformations.
Sujet(s)
Artère subclavière , Humains , Mâle , Artère subclavière/malformations , Artère subclavière/imagerie diagnostique , Cartilage cricoïde/imagerie diagnostique , Cartilage cricoïde/malformations , Laryngoscopie , Tomodensitométrie , Cartilage thyroïde/malformations , Cartilage thyroïde/imagerie diagnostique , Laryngocèle/imagerie diagnostique , Laryngocèle/chirurgie , Laryngocèle/diagnostic , Laryngocèle/complications , Trachéotomie , Malformations cardiovasculairesRÉSUMÉ
Surgical decompression of the thoracic outlet, along with treatment of the involved nerve or vessel, is the accepted treatment modality when indicated. Although neurogenic thoracic outlet syndrome (TOS) is often operated via the axillary approach and venous TOS via the paraclavicular approach, arterial TOS is almost always operated via the supraclavicular approach. The supraclavicular approach provides excellent access to the artery, brachial plexus, phrenic nerve, and the cervical and/or first ribs, along with any bony or fibrous or muscular abnormality that may be causing compression of the neurovascular structures. Even for neurogenic TOS, for which the axillary approach offers good cosmesis, the supraclavicular approach helps with adequate decompression while preserving the first rib. This approach may also be sufficient for thin patients with venous TOS. For arterial TOS, a supraclavicular incision usually suffices for excision of bony abnormality and repair of the subclavian artery.
Sujet(s)
Décompression chirurgicale , Syndrome du défilé thoracobrachial , Humains , Décompression chirurgicale/méthodes , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Syndrome du défilé thoracobrachial/chirurgie , Syndrome du défilé thoracobrachial/physiopathologie , Syndrome du défilé thoracobrachial/imagerie diagnostique , Résultat thérapeutiqueRÉSUMÉ
A right aortic arch and aberrant subclavian artery result from an interruption in the remodeling of the pharyngeal arch arteries. We occasionally encounter this anatomical variation during angiography. Patients with disorders such as Down syndrome and congenital heart disease show a high incidence of an aberrant right subclavian artery, and this anomaly can cause symptomatic esophageal or tracheal compression. The root of the aberrant artery may show dilatation(referred to as a Kommerell diverticulum), dissection, intramural hematoma, or rupture necessitating cardiac intervention using a surgical or endovascular approach. Neurointerventionalists should have working knowledge of the anatomy to rapidly understand the anatomy and ensure a safe procedure. A left transradial approach should be considered if prior knowledge of the aberrant subclavian anatomy is available.
Sujet(s)
Aorte thoracique , Artère subclavière , Humains , Aorte thoracique/malformations , Aorte thoracique/imagerie diagnostique , Artère subclavière/malformations , Artère subclavière/imagerie diagnostique , Remodelage vasculaire , Malformations cardiovasculairesRÉSUMÉ
Dysphagia lusoria is a rare pediatric condition caused by extrinsic compression of the esophagus by an abnormal subclavian artery. The most common congenital abnormality in aortic arch development is an aberrant right subclavian artery. The retroesophageal right subclavian artery is typically symptomatic in 10-33% of cases. The patient, an 8-month-old girl with a history of early dysphagia and stridor, was diagnosed with an abnormal right subclavian artery. She was admitted to the pneumology service multiple times due to stridor, vomiting, and failure to thrive. During hospitalization at the gastroenterology service, a barium swallow and an upper digestive endoscopy indicated an abnormal right subclavian artery, which was confirmed by an Angiography CT scan. She underwent surgery at the age of sixteen months. All symptoms are resolved following surgical intervention, and the patient is still asymptomatic and in good clinical condition 12 months later. Every physician should be aware of abnormal right subclavian arteries and their clinical symptoms in children and adults in order to recognize and diagnose them early. Only an early evaluation may reduce complications such as delayed physical growth, dysphagia, and recurrent respiratory infections.
Sujet(s)
Malformations cardiovasculaires , Troubles de la déglutition , Artère subclavière/malformations , Adulte , Femelle , Humains , Enfant , Nourrisson , Troubles de la déglutition/étiologie , Artère subclavière/imagerie diagnostique , Bruits respiratoires , TroncRÉSUMÉ
We report the case of a 36-year-old female whose dysphagia revealed a congenital anomaly of the thoracic aorta: the right aortic arch with mirror image branching. This is a rare embryonic developmental anomaly where the aorta wraps around the right bronchus and the supra-aortic trunks emerge from the arch in the opposite order to normal. Most of the patients are asymptomatic unless there is a significant compression of mediastinal structures. Major compression of the esophagus or trachea, aneurysmal disease, dissection of the thoracic aorta, or the presence of a Kommerell diverticulum larger than 2 cm may require a surgical repair. There is no standard treatment and it must be adapted to the clinical presentation and the anatomic configuration of each patient. Our patient did not receive any treatment for her condition.
Nous rapportons le cas d'une patiente de 36 ans dont le tableau de dysphagie a permis de mettre en évidence une anomalie congénitale de l'aorte thoracique : l'arc aortique droit avec image en miroir. Il s'agit d'une anomalie de développement embryonnaire rare où l'aorte s'enroule autour de la bronche souche droite et où les troncs supra-aortiques émergent de la crosse dans l'ordre inverse et opposé à la normale. La grande majorité des patients est asymptomatique, à moins qu'il existe une compression des structures médiastinales. Une compression majeure de l'oesophage ou de la trachée, une maladie anévrismale, une dissection de l'aorte thoracique ou la présence d'un diverticule de Kommerell de plus de 2 cm peuvent justifier une sanction chirurgicale. Il n'y a pas de traitement standard et celui-ci doit être adapté à la présentation clinique et à la configuration anatomique du patient. Notre patiente n'a bénéficié d'aucun traitement pour son affection.
Sujet(s)
Aorte thoracique , Troubles de la déglutition , Femelle , Humains , Adulte , Aorte thoracique/imagerie diagnostique , Aorte thoracique/malformations , Aorte thoracique/chirurgie , Troubles de la déglutition/étiologie , Médiastin , Artère subclavière/imagerie diagnostique , Artère subclavière/malformations , Artère subclavière/chirurgieSujet(s)
Maladie de Behçet , Enfant , Humains , Maladie de Behçet/complications , Maladie de Behçet/diagnostic , Cyclophosphamide/usage thérapeutique , Cyclophosphamide/administration et posologie , Artère fémorale/imagerie diagnostique , Artère fémorale/anatomopathologie , Artère subclavière/imagerie diagnostique , Artère subclavière/anatomopathologie , Échographie-doppler couleurSujet(s)
Malformations cardiovasculaires , Interventions chirurgicales robotisées , Artère subclavière , Humains , Artère subclavière/chirurgie , Artère subclavière/malformations , Artère subclavière/imagerie diagnostique , Interventions chirurgicales robotisées/méthodes , Malformations cardiovasculaires/chirurgie , Malformations cardiovasculaires/imagerie diagnostique , Anévrysme/chirurgie , Anévrysme/imagerie diagnostique , Résultat thérapeutique , Mâle , Procédures de chirurgie vasculaire/méthodes , Femelle , Angiographie par tomodensitométrie , Interventions chirurgicales mini-invasives/méthodesRÉSUMÉ
We present a case of Takayasu's arteritis in a woman in her 30s, who exhibited visual symptoms and ophthalmic manifestations of the disease, specifically Takayasu's retinopathy stage 4, in both eyes. Despite severe narrowing of all branches of the aortic arch and compromised perfusion in both upper limbs, she had no history of intermittent claudication. Doppler study and CT angiography revealed diffuse circumferential wall thickening of bilateral common carotid, subclavian and axillary arteries. Treatment involved retinal laser photocoagulation and immune suppression. This case underscores that advanced Takayasu's retinopathy can be an initial presentation of Takayasu's arteritis even in a state of severely compromised peripheral limb circulation.
Sujet(s)
Maladie de Takayashu , Humains , Maladie de Takayashu/complications , Maladie de Takayashu/diagnostic , Femelle , Adulte , Rétinopathies/étiologie , Rétinopathies/diagnostic , Artère axillaire/imagerie diagnostique , Artère subclavière/imagerie diagnostique , Angiographie par tomodensitométrie , Coagulation par laserSujet(s)
Embolie pulmonaire , Artère subclavière , Humains , Embolie pulmonaire/imagerie diagnostique , Embolie pulmonaire/étiologie , Embolie pulmonaire/complications , Artère subclavière/imagerie diagnostique , Mâle , Femelle , Artériopathies oblitérantes/imagerie diagnostique , Artériopathies oblitérantes/étiologie , Artériopathies oblitérantes/complications , Artériopathies oblitérantes/chirurgie , Embolie paradoxale/imagerie diagnostique , Embolie paradoxale/complications , Embolie paradoxale/étiologie , Adulte d'âge moyen , Sujet âgéRÉSUMÉ
PURPOSE: A right aortic arch (RAA) is a rare vascular anomaly that often coexists with an aberrant left subclavian artery (ALSA). Due to the rarity of RAA, the development of an ALSA is not well understood. METHOD: We describe a case in which a 58-year-old man who was scheduled to undergo posterior decompression and fusion surgery for thoracic ossification of the posterior longitudinal ligament from Th1 to Th3 was found to have a RAA and an ALSA. RESULTS: Preoperative computed tomography angiography demonstrated a RAA and an ALSA. The ALSA was extremely tortuous and ran in the paraspinal muscles behind the thoracic laminae, which meant it was in the surgical field. The ALSA arose from the descending aorta and bifurcated into the left segmental arteries of Th1 and Th2, and also bifurcated into the left vertebral artery, which had a normal subsequent course. The dysplastic ALSA was considered to have developed from the thoracic intersegmental artery. Based on preoperative examination findings, we performed spinal surgery without vessel injury. CONCLUSION: We report a rare case of a dysplastic ALSA that developed from the thoracic intersegmental artery with a RAA. The knowledge of this anomaly provides safety in spinal surgery of the cervicothoracic junction.
Sujet(s)
Malformations cardiovasculaires , Artère subclavière/malformations , Anomalies vasculaires , Mâle , Humains , Adulte d'âge moyen , Aorte thoracique/imagerie diagnostique , Aorte thoracique/chirurgie , Aorte thoracique/malformations , Malformations cardiovasculaires/imagerie diagnostique , Malformations cardiovasculaires/chirurgie , Malformations cardiovasculaires/complications , Artère subclavière/imagerie diagnostique , Anomalies vasculaires/complicationsRÉSUMÉ
OBJECTIVE: To assess the effectiveness and safety of neurological interventions using the right transradial approach (R-TRA) in patients with aberrant right subclavian artery (ARSA). METHODS: We retrospectively analyzed cases that underwent cerebral angiography and interventions at Huangpi District People's Hospital from January 2023 to July 2023. Out of 335 cases, 5 patients with ARSA were identified. RESULTS: All 5 cases underwent diagnostic cerebral angiography via R-TRA. Two of the patients received interventions via R-TRA: 1 underwent right internal carotid artery balloon dilation angioplasty, while another underwent left vertebral artery stenting. No surgery-related complications were observed during these procedures. CONCLUSIONS: R-TRA proves to be a safe and effective option for neuro-interventional surgery in patients with ARSA.
Sujet(s)
Malformations cardiovasculaires , Angiographie cérébrale , Artère subclavière , Humains , Artère subclavière/malformations , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Femelle , Mâle , Études rétrospectives , Adulte d'âge moyen , Malformations cardiovasculaires/chirurgie , Malformations cardiovasculaires/imagerie diagnostique , Angiographie cérébrale/méthodes , Adulte , Artère radiale/chirurgie , Artère radiale/imagerie diagnostique , Angioplastie par ballonnet/méthodes , Endoprothèses , Sujet âgé , Anévrysme/chirurgie , Anévrysme/imagerie diagnostique , Résultat thérapeutiqueRÉSUMÉ
PURPOSE: This study aims to explore the correlation between fetal aberrant right subclavian artery (ARSA) and chromosomal disorders, with a specific focus on Down syndrome and DiGeorge syndrome. METHODS: From November 2017 to February 2020, we conducted fetal anomaly screening and assessed the fetal heart in 8494 at our institution. The right subclavian artery tracing was assessed using Doppler ultrasonography following the 3-vessel and tracheal views (3VTV) in the fetal heart scan. RESULTS: ARSA was found in 31 fetuses, which accounts for 0.36% of the total of 8494 fetuses. 96.8% of fetuses with ARSA were found to have normal chromosomal analysis. We identified only one case of trisomy 21 as the chromosomal condition present. In 80% of the identified ARSA, there were no additional associated findings. CONCLUSION: ARSA is a rare condition that often does not manifest any concomitant abnormalities. The majority of ARSA instances identified in the second trimester are euploid. If ARSA is the only sonographic finding during fetal anomaly screening and there are no maternal or laboratory risk factors, further evaluation with non-invasive diagnostics may be recommended. Non-invasive genetic testing may be used for additional investigation.
Sujet(s)
Malformations cardiovasculaires , Artère subclavière , Échographie prénatale , Humains , Artère subclavière/malformations , Artère subclavière/imagerie diagnostique , Femelle , Grossesse , Malformations cardiovasculaires/imagerie diagnostique , Adulte , Syndrome de Down/imagerie diagnostique , Anévrysme/imagerie diagnostique , Syndrome de DiGeorge/imagerie diagnostique , Nouveau-né , Deuxième trimestre de grossesse , Troubles de la déglutition/imagerie diagnostiqueRÉSUMÉ
A case of a 40-year-old male patient with a right subclavian artery aneurysm of fibromuscular dysplasia origin is reported. The patient presented with thoracic outlet-like symptoms and underwent aneurysm resection. Microscopic examination revealed intimal and medial fibroplasia. Additional cases of fibromuscular dysplasia at this rare location are reviewed, indicating a male and right-sided predominance. The most frequent clinicopathological manifestation was an aneurysm, with the histopathological pattern characterized by medial fibroplasia. Treatment modalities included the use of either graft prosthesis or end-to-end anastomosis.
Sujet(s)
Anévrysme , Dysplasie fibromusculaire , Artère subclavière , Humains , Dysplasie fibromusculaire/anatomopathologie , Dysplasie fibromusculaire/complications , Dysplasie fibromusculaire/chirurgie , Mâle , Artère subclavière/anatomopathologie , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Adulte , Anévrysme/anatomopathologie , Anévrysme/chirurgie , Anévrysme/imagerie diagnostique , Résultat thérapeutique , Implantation de prothèses vasculairesSujet(s)
Anévrysme , Implantation de prothèses vasculaires , Procédures endovasculaires , Artère subclavière , Humains , Artère subclavière/chirurgie , Artère subclavière/imagerie diagnostique , Anévrysme/chirurgie , Anévrysme/imagerie diagnostique , Procédures endovasculaires/instrumentation , Procédures endovasculaires/méthodes , Implantation de prothèses vasculaires/instrumentation , Implantation de prothèses vasculaires/méthodes , Mâle , Angiographie par tomodensitométrie , Résultat thérapeutique , Sujet âgé , Prothèse vasculaire , EndoprothèsesRÉSUMÉ
OBJECTIVES: To evaluate the feasibility and clinical benefit of utilizing image fusion for thoracic endovascular repair (TEVAR) with in situ fenestration (ISF-TEVAR). MATERIALS AND METHODS: Between January 2020 and December 2020, we prospectively collected 18 consecutive cases with complex thoracic aortic lesions who underwent image fusion guided ISF-TEVAR. As a control group, 18 patients were collected from historical medical records from June 2019 to December 2019. The fusion group involved the use of 3D fusion of CTA and fluoroscopic images for real-time 3D guidance, and the control group involved the use of only regular fluoroscopic images for guidance. The total contrast medium volume, hand-injected contrast medium volume, overall operative time, radiation dose and fluoroscopy time were compared between the two groups. Accuracy was measured based on preoperative CTA and intraoperative digital subtraction angiography. RESULTS: 3D fusion imaging guidance was successfully implemented in all patients in the fusion group. Hand-injected contrast medium volume and overall operative time were significantly lower in the fusion group than in the control group (p = .028 and p = .011). Compared with the control group, the fusion group showed a significant reduction in time and radiation dose-area product (DAP) for fluoroscopy (p = .004 and p = .010). No significant differences in total radiation dose (DAP) or total contrast medium volume were observed (p = .079 and p = .443). Full accuracy was achieved in 8 cases (44%), with a mean deviation of 2.61 mm ± 3.1 (range 0.0-8.4 mm). CONCLUSIONS: 3D image fusion for ISF-TEVAR was associated with a significant reduction in hand-injected contrast medium, time and radiation exposure for fluoroscopy and overall operative time. The image fusion guidance showed potential clinical benefits towards improved treatment safety and accuracy for complex thoracic endovascular interventions.