In order to overcome the geometrical and physical limitations of conventional rotating and piezosurgery instruments used to perform bone osteotomies, as well as the difficulties in translating ...digital planning to the operating room, a stand-alone robot-guided laser system has been developed by Advanced Osteotomy Tools, a Swiss start-up company. We present our experiences of the first-in-man use of the Cold Ablation Robot-guided Laser Osteotome (CARLO
).
The CARLO
device employs a stand-alone 2.94-µm erbium-doped yttrium aluminum garnet (Er:YAG) laser mounted on a robotic arm. A 19-year-old patient provided informed consent to undergo bimaxillary orthognathic surgery. A linear Le Fort I midface osteotomy was digitally planned and transferred to the CARLO
device. The linear part of the Le Fort I osteotomy was performed autonomously by the CARLO
device under direct visual control. All pre-, intra-, and postoperative technical difficulties and safety issues were documented. Accuracy was analyzed by superimposing pre- and postoperative computed tomography images.
The CARLO
device performed the linear osteotomy without any technical or safety issues. There was a maximum difference of 0.8 mm between the planned and performed osteotomies, with a root-mean-square error of 1.0 mm. The patient showed normal postoperative healing with no complications.
The newly developed stand-alone CARLO
device could be a useful alternative to conventional burs, drills, and piezosurgery instruments for performing osteotomies. However, the technical workflow concerning the positioning and fixation of the target marker and the implementation of active depth control still need to be improved. Further research to assess safety and accuracy is also necessary, especially at osteotomy sites where direct visual control is not possible. Finally, cost-effectiveness analysis comparing the use of the CARLO
device with gold-standard surgery protocols will help to define the role of the CARLO
device in the surgical landscape.
Abstract The ameloblastic fibro-odontoma (AFO) is a rare mixed odontogenic tumor. Clinically AFO presents as a hamartoma or immature odontoma. The AFO is a well-encapsulated, painless, slow-growing ...and expanding tumor in young patients. Histologically, it has been classified as an ameloblastic fibroma or odontoma. Despite numerous efforts, there is still considerable confusion concerning the nature, the histology and the surgical therapy of this lesion. However, it can present with progressive growth causing bone destruction and significant deformity. The transformation of AFO in sarcoma is also known and extremely rare. Therefore a long term follow up is recommended. Enucleation still remains the gold standard. We are discussing our experience with AFO focused on children in clinical and surgical features and reviewing the relevant literature.
Bisphosphonate-associated osteonecrosis of the jaws (MRONJ/BP-ONJ/BRONJ) is a commonly seen disease. During recent decades, major advances in diagnostics have occurred. Once the clinical picture ...shows typical MRONJ features, imaging is necessary to determine the size of the lesion. Exposed bone is not always painful, therefore a thorough clinical examination and radiological imaging are essential when MRONJ is suspected.
In this paper we will present the latest clinical update on the imaging options in regard to MRONJ: X-ray/Panoramic Radiograph, Cone Beam Computed Tomography (CBCT) and Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Nuclear Imaging, Fluorescence-Guided Bone Resection.
Which image modality is chosen depends not only on the surgeon's/practitioner's preference but also on the available imaging modalities. A three-dimensional imaging modality is desirable, and in severe cases necessary, for extended resections and planning of reconstruction.
Aim of the study was to prove the safety, accuracy characteristics of contact-free laser osteotomy executed with the cold ablation and robot-guided Er:YAG laser osteotome in a human cadaver test.
On ...six human cadavers mandible resections with a swallowtail like pattern were performed with the laser system on each side. The defects were reconstructed with a fibula graft of identical design and enlarged by 0.2 units. Mandibles and fibulas width as well surgery times were recorded. Additionally a Le Fort I and median mandible split were done. Macroscopically, the bone margins were examined for necrosis.
Laser osteotomies of the mandible up to a depth of 23 mm were possible without any thermal damage. Repeatability and precision of the system could be easily assessed. With the navigation system precise control of localization was achievable. Mean surgery time for the mandible resection was 13.32 min and for the fibula osteotomy 12.38 min.
The simply transmission of a cold ablation and robot-guided laser osteotome in an operation room identical environment for surgical interventions could be demonstrated. Precise osteotomy patterns with freedom in the design and carbonisation-free cut surfaces have been shown.
Most industrial laser applications utilize computer and robot assistance, for guidance, safety, repeatability, and precision. In contrast, medical applications using laser systems are mostly ...conducted manually. The advantages can be effective only when the system is coupled to a robotic guidance, as operating by hand does not reach the required accuracy. We currently developed the first laser osteotome which offers preoperative planning based on CT data, robot guidance, and a precise execution of the laser cuts. In an animal trial, our system was used to create a grid pattern of the same depth on the inner layer of parietal bone in 12 adult sheep. The same bone cuts were done with piezoelectric osteotome on the contralateral side. The micro-CT and histological analysis showed more new mineralized bone in the laser group compared to the piezoelectric group. As well, a cutting pattern with especially a constant osteotomy depth in the laser group was demonstrated. The here presented autonomous osteotomy tool shows not only an advantage in early bone healing stage but additionally sharp bone cuts with a very high accuracy and freely selectable design cuts.
Background and Purpose
Rhino–orbito–cerebral mucormycosis (ROCM) is a rare and potentially fatal invasive fungal infection which usually occurs in diabetic and other immunocompromised patients. This ...infection is associated with high morbidity and mortality rates. Prompt diagnosis and rapid aggressive surgical debridement and antimycotic therapy are essential for the patient's survival.
Herein, we reviewed the localization and treatment strategies in patients with ROCM and diabetes as an underlying condition. Furthermore, we report one case of ROCM in our department.
Materials and Methods
From 117 identified studies published in PubMed, 14 publications—containing data from 54 patients—were included. All patients were diagnosed clinically and by histopathological and/or bacteriological analysis for ROCM caused by the order Mucorales.
Conclusion
Uncontrolled diabetes mellitus is one of the main risk factors for ROCM. A successful management of ROCM requires an early diagnosis, a prompt systemic antifungal therapy, and a rapid aggressive surgical debridement including exploration of the pterygopalatine fossa. An orbital exenteration may be necessary.
•The increasing intake of anticoagulants at an advanced age is considered a predisposing factor for retrobulbar haematomas.•Patients undergoing anticoagulant therapy should be carefully monitored for ...occurrence of delayed retrobulbar haematomas.•Treatment options of retrobulbar haematoma can vary depending on the prescribed anticoagulant.
The present retrospective study aimed to evaluate the frequency and distribution of retrobulbar haematoma (RBH) among 26 patients (12 male/14 female) who had suffered maxillofacial trauma/surgery, with special focus on anticoagulants, causes of accidents, treatment, and outcome.
Patient ages ranged from 8 to 94 years, with a mean of 65 years. Among all patients, 43% had received anticoagulant therapy at admission; 92.3% had a previous history of maxillofacial trauma.
The most frequent cause of RBH were falls (65.4%), and three patients experienced RBH postoperatively after treatment using polydioxanone foil. Postoperatively (after RBH relief), 33.3% of the patients reported persistent complete visual loss; of these patients, 29% had received anticoagulation therapy, and the oral anticoagulant intake was not documented in further 29% of the patients.
Awareness of this pathologic process is crucial for preventing permanent loss of vision via early diagnosis and adequate therapy. With increasing age, patients are more likely to receive an anticoagulant, which leads to a higher risk of RBH. Because falling was the most frequent cause of RBH in our patient population and increases in frequency with increasing age, fall prevention is crucial.
Several post-processing algorithms for 3D visualization of the skull in craniosynostosis with their specific advantages and disadvantages have been already described. The Finite Element Method (FEM) ...described herein can also be used to evaluate the efficacy of the cutting patterns with respect to an increase in the projected surface area under assumed uniform loading of the manipulated and cut bone segments.
The FEM analysis was performed. Starting with the classic cranial osteotomies for bifrontal craniotomy and orbital bandeau a virtually mirroring of the unaffected triangular shaped frontal bone was performed to achieve a cup-shaped sphere of constant thickness of 2.5 mm with a radius of 65 mm. Mechanical properties required for the analysis were Young's modulus of 340 MPa and Poisson's ratio of 0.22. Four different cutting patterns from straight to curved geometries have been projected onto the inner surface of the sphere with a cutting depth set to 2/3rds of the shell thickness. The necessary force for the deformation, the resulting tensions and the volume loss due to the osteotomy pattern were measured.
Better outcomes were realized with pattern D. The necessary force was 73.6% smaller than the control group with 66N. Best stress distribution was achieved. Curved cutting patterns led to the highest peak of stress and thus to a higher risk of fracture. Straight bone cuts parallel to the corners or to the thighs of the sphere provided a better distribution of stresses with a small area with high stress. Additionally, also with pattern D a surface increase of 20.7% higher than reference was registered.
As a proof of concept for different cutting geometries for skull molding in the correction of craniosynostosis, this computational model shows that depending of the cutting pattern different biomechanical behavior is achieved.
The recommendation issued by the American Academy of Pediatrics in the early 1990s to position infants on their back during sleep to prevent sudden infant death syndrome (SIDS) has dramatically ...reduced the number of deaths due to SIDS but has also markedly increased the prevalence of positional skull deformation in infants.
Deformation of the base of the skull occurs predominantly in very severe deformational plagiocephaly and is accompanied by facial asymmetry, as well as an altered ear position, called ear shift. Moulded helmet therapy has become an accepted treatment strategy for infants with deformational plagiocephaly. The aim of this study was to determine whether facial asymmetry could be corrected by moulded helmet therapy.
In this retrospective, single-centre study, we analysed facial asymmetry of 71 infants with severe deformational plagiocephaly with or without deformational brachycephaly who were undergoing moulded helmet therapy between 2009 and 2013. Computer-assisted, three-dimensional, soft-tissue photographic scanning was used to record the head shape before and after moulded helmet therapy. The distance between two landmarks in the midline of the face (i.e., root of the nose and nasal septum) and the right and left tragus were measured on computer-generated indirect and objective 3D photogrammetry images. A quotient was calculated between the two right- and left-sided distances to the midline. Quotients were compared before and after moulded helmet therapy. Infants without any therapy served as a control group.
The median age of the infants before onset of moulded helmet therapy was 5 months (range 3–16 months). The median duration of moulded helmet therapy was 5 months (range 1–16 months). Comparison of the pre- and post-treatment quotients of the left vs. right distances measured between the tragus and root of the nose (n = 71) and nasal septum (n = 71) revealed a significant reduction of the asymmetry (Tragus-Nasion-Line Quotient: 0.045–0.022; p < 0.0001; Tragus-Subnasale-Line Quotient: 0.045–0.021; p < 0.0001). The control group without treatment showed no significant change in the quotient (Tragus-Nasion-Line Quotient no helmet: 0.049–0.055/Tragus-Subnasale-Line Quotient no helmet: 0.039–0.055).
Moulded helmet therapy can correct facial symmetry in infants with deformational plagiocephaly and associated facial and basal skull asymmetry.
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