We aim at testing the possibility to build patientspecific structural finite element models (FEMs) of the mitral valve (MV) from cardiac magnetic resonance (CMR) imaging and to use them to predict the outcome of mitral annuloplasty procedures. MV FEMs were built for one healthy subject and for one patient with ischemic mitral regurgitation. On both subjects, CMR imaging of 18 longaxis planes was performed with a temporal resolution of 55 time-frames per cardiac cycle. Three-dimensional MV annulus geometry, leaflets surface and PM position were manually obtained using custom software. Hyperelastic anisotropic mechanical properties were assigned to MV tissues. A physiological pressure load was applied to the leaflets to simulate valve closure until peak systole. For the pathological model only, a further simulation was run, simulating undersized rigid annuloplasty before valve closure. Closure dynamics, leaflets stresses and tensions in the subvalvular apparatus in the healthy MV were consistent with previous computational and experimental data. The regurgitant valve model captured with good approximation the real size and position of regurgitant areas at peak systole, and highlighted abnormal tensions in the annular region and sub-valvular apparatus. The simulation of undersized rigid annuloplasty showed the restoration of MV continence and normal tensions in the subvalvular apparatus and at the annulus. Our method seems suitable for implementing detailed patient-specific MV FEMs to simulate different scenarios of clinical interest. Further work is mandatory to test the method more deeply, to reduce its computational time and to expand the range of modeled surgical procedures.

Objective: Congenital bicuspid aortic valves frequently cause aortic stenosis or regurgitation. Improved understanding of valve and root biomechanics is needed to achieve advancements in surgical repair techniques. By using imaging-derived data, finite element models were developed to quantify aortic valve and root biomechanical alterations associated with bicuspid geometry.Methods: A dynamic 3-dimensional finite element model of the aortic root with a bicuspid aortic valve (type 1 right/left) was developed. The model's geometry was based on measurements from 2-dimensional magnetic resonance images acquired in 8 normotensive and otherwise healthy subjects with echocardiographically normal function of their bicuspid aortic valves. Numeric results were compared with those obtained from our previous model representing the normal root with a tricuspid aortic valve. The effects of raphe thickening on valve kinematics and stresses were also evaluated.Results: During systole, the bicuspid valve opened asymmetrically compared with the normal valve, resulting in an elliptic shape of its orifice. During diastole, the conjoint cusp occluded a larger proportion of the valve orifice and leaflet bending was altered, although competence was preserved. The bicuspid model presented higher stresses compared with the tricuspid model, particularly in the central basal region of the conjoint cusp (þ800%). The presence of a raphe partially reduced stress in this region but increased stress in the other cusp.Conclusions: Aortic valve function is altered in clinically normally functioning bicuspid aortic valves. Bicuspid geometry per se entails abnormal leaflet stress. The stress location suggests that leaflet stress may play a role in tissue remodeling at the raphe region and in early leaflet degeneration.

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In the bicuspid aortic valve commonly defined as normofunctional by echocardiographic criteria, restricted systolic conjoint cusp motion causes flow deflection. The novel measurement introduced can quantify restricted cusp opening, possibly assuming prognostic importance.

In this work, we consider the blood fluid-dynamics in the ascending aorta in presence of a normally functioning bicuspid aortic valve (BAV). In particular, we perform an unsteady finite element study in real geometries with physiological velocity boundary conditions at the inlet to assess the effect of the inclusion of the leaflets on the fluid-dynamic abnormalities characterizing BAV cases. To this aim, we perform a comparison in two geometries (a dilated and a non-dilated ones) among three scenarios which are built up for each geometry: BAV without leaflets, BAV with leaflets, and tricuspid case with leaflets. For each case, we compute four indices quantifying flow asymmetry, reversal flows, helical patterns, and wall shear stresses. Our results show that the inclusion of the leaflets increases the fluid-dynamics abnormalities, especially for the non-dilated configuration, which presents a greater increment of the indices. In particular, we observe that the values of the time-averaged wall shear stress and of the systolic jet asymmetry increase by approximatively 100 and 40%, respectively, when considering the leaflets.

Rationale: Retroperitoneal schwannomas are very rare and may grow very close to major abdominal vessels. Since the surgical approach to the retroperitoneal space may be complex due to surrounding vital organs, including major vessels, laparoscopic surgery is challenging and has only been recently adopted. Here, we report a case of laparoscopic resection of a large retroperitoneal schwannoma attached to large vital vessels. Patient concerns: A 62-year-old woman presented with a chief complaint of pain in the lower right limb with consequent claudication, which had lasted for approximately 1 year. Diagnoses: Magnetic resonance imaging revealed a solid oval mass measuring 45 × 32 × 39 mm, located medially to the right iliopsoas muscle at the level of the intersomatic space between the 5th lumbar vertebra and the 1st sacral vertebra. This mass was inhomogeneously hypointense in T2 due to the presence of cystic areas, with intense and inhomogeneous contrast enhancement, compatible with the diagnosis of a schwannoma. The mass compressed the inferior caval vein near its bifurcation and the right common iliac vein, anteriorly dislocating the ipsilateral iliac arterial axis. Interventions: A multidisciplinary team skilled in vascular and pelvic laparoscopy was involved. The patient underwent laparoscopic surgery via an anterior transperitoneal approach with right adnexectomy and radical excision of the tumor. The surgery lasted 120 minutes without intraoperative complications. Blood loss was less than 100 mL. The histologic diagnosis was a benign Schwannoma; grade I according to World Health Organization classification. Outcomes: The postoperative course was uneventful. At the 10-month follow-up, the patient had no recurrences and was asymptomatic. Lessons: Laparoscopic removal of large retroperitoneal schwannomas, even if attached to major vital vessels, is feasible and safe when performed by experienced surgeons.

Aneurysmal bone cysts (ABC) are benign osteolytic lesions that are more common in young people than in adults and involve the skull only exceptionally. The origin of ABC is still debated; indeed, some authors consider ABC to be an anomalous bony reaction that is secondary to traumas or tumours. Conversely, others consider ABC to be a distinct entity. A case of a healthy young female affected by a left frontal ABC is reported here. The clinical onset was characterised by the sudden appearance of a tender and mildly painful frontal mass. Neuroradiological assessment showed a well-circumscribed lytic lesion of the frontal bone with predominantly outward extension. En bloc surgical removal of the lesion was successfully achieved; a reconstructive cranioplasty was also performed to repair the cranial defect. The rarity of the condition described, together with the absence of clear guidelines, prompted us to review the more recent literature with the twin goals of identifying radiological features and becoming able to address the diagnosis and rules for treatment of such a rare entity.