Correction to: Clinical relevance of the tumor microenvironment and immune escape of oral squamous cell carcinoma.

The original version of this article [1], published on 5 April 2016, contains a mistake. In the 'Role of pH stabilisation' section, "intracellular pH" has been incorrectly abbreviated as "pHe". The correct abbreviation is "pHi". The affected sentence with the correct abbreviation is given below.

Virtual Surgery Planning in Orthomorphic Correction of Mandibular Dysmorphology.

Three-dimensional virtual surgery programs are widely available for orthognathic surgery. The advent of imaging software programs has proved to be useful for diagnosis, treatment planning, outcome measurement, and three-dimensional surgical simulation. Complex maxillofacial malformations continue to present challenges in analysis and correction beyond modern technology. Orthomorphic correction for mandibular dysmorphology refers to basal bone movement without any change in dental component. The purpose of this paper is to present a virtual surgery planning for surgeons to perform the orthomorphic surgery with precision and quantification. Moreover, it provides an essential educational tool for patients to foresee predicted surgical outcome.

Le Fort I Disassembly for the Management of Juvenile Ossifying Fibroma Extending To the Skull Base.

Ossifying fibroma is a rare benign osteogenic neoplasm arising from undifferentiated cells of the periodontal ligament. Ossifying fibroma have a well-defined border that differentiates it from fibrous dysplasia clinically; these tumors manifest as a round or ovoid, expansile, painless, slow-growing mass may displace the roots of adjacent teeth and also cause root resorption. A variety of approaches for resection of the maxilla have been described. Most involve the use of facial and lip-splitting incisions to gain wide access. Surgical approach specifically to the ossifying fibroma located in the midface includes the Le Fort I approach, Caldwell-Luc access, lateral rhinotomy with medial or total maxillectomy, external ethmoidectomy, and endoscopic surgery. The access through Le Fort I disassembly is a versatile approach not only because of the aesthetic potential in using intraoral incision but also due to its minimal invasiveness, lesser complications and gives the possibility of reconstruction in a single operation. Le Fort I disassembly followed by an excision appears to be a versatile, secure, and satisfactory option.

Clinical relevance of the tumor microenvironment and immune escape of oral squamous cell carcinoma.

BACKGROUND: Changes in the tumor microenvironment and immune surveillance represent crucial hallmarks of various kinds of cancer, including oral squamous cell carcinoma (OSCC), and a close crosstalk of hypoxia regulating genes, an activation of chemokines and immune cells has been described. METHODS: A review about the pivotal role of HIF-1, its crosstalk to various cornerstones in OSCC tumorigenesis is presented. RESULTS: Hypoxia is a frequent event in OSCC and leads to a reprogramming of the cellular metabolism in order to prevent cell death. Hypoxic OSCC cells induce different adaptive changes such as anaerobic glycolysis, pH stabilisation and alterations of the gene and protein expression profile. This complex metabolic program is orchestrated by the hypoxia inducible factor (HIF)-1, the master regulator of early tumor progression. Hypoxia-dependent and -independent alterations in immune surveillance lead to different immune evasion strategies, which are partially mediated by alterations of the tumor cells, changes in the frequency, activity and repertoire of immune cell infiltrates and of soluble and environmental factors of the tumor micromilieu with consecutive generation of an immune escape phenotype, progression of disease and poor clinical outcome of OSCC patients. CONCLUSIONS: This review focusses on the importance of HIF-1 in the adaption and reprogramming of the metabolic system to reduced oxygen values as well as on the role of the tumor microenvironment for evasion of OSCC from immune recognition and destruction.

Fabrication of Patient Specific Titanium Implants for Correction of Cranial Defects: A Technique to Improve Anatomic Contours and Accuracy.

Hard tissue cranial defects may result from traumatic or iatrogenic etiology and warrants adequate reconstruction to provide protection to the underlying brain and cosmesis. Various techniques have been described in the literature for fabrication of patient specific titanium cranial implants. The process of fabrication of titanium patient specific implants (PSI) can be broadly classified into indirect and direct techniques. With the improvements in the medical imaging and computational modeling, direct technique of computer assisted prefabricated patient specific implants have gained popularity. However indirect method of PSI fabrication hold some specific advantage. Here we describe a technique for fabrication of titanium PSI by combining the principles of direct and indirect methods for reconstruction of cranial defects.

Custom made orthotic device for maintaining skull architecture during the postoperative period in infants undergoing craniosynostosis surgery.

AIM: To fabricate a cost effective, indigenous and simple orthotics helmet for post-operative cranial molding in patients with craniosynostosis surgery. METHODS: We present a case of 15 month old infant with secondary cranial vault deformity. Cranial vault remodeling surgery involving the posterior skull was planned and executed to increase the posterior gap, so that brain growth would be facilitated towards this empty space. Materials such as thermoplastic sponge, thermoplastic ionomer resin sheet, soft sponge and Velcro straps are used to fabricate a cranial orthotics helmet. RESULTS: We have successfully used the above materials to fabricate the orthotics helmet for post-operative cranial molding. CONCLUSION: The technique described in this article is simple and cost effective. It can be custom made according to the demands of the surgical technique and the type of synostosis. It favors an individualistic prognosis, and proves worthwhile as every synostosis requires a unique treatment plan. It is an excellent adjuvant to craniosynostosis remodeling surgery.

Subdural hygroma after craniosynostosis remodeling surgery.

Craniosynostosis is defined as the premature fusion of the cranial sutures and can cause functional impairment or cosmetic deformity. Surgical techniques for the correction of craniosynostosis have changed overtime, as so have the intraoperative and postoperative complications. Extensive surgeries involving fronto-orbital unit repositioning and cranial vault remodeling are associated with various complications. Intraoperative and postoperative hemorrhage, venous infarct, air embolism, hydrocephalus, cerebrospinal fluid leak, as well as meningitis are a few complications associated with cranial vault remodeling surgery. Postoperative complications can increase the morbidity and mortality associated with these procedures. Identification of the complications and their timely management should be a part of every craniofacial reconstruction team's training program.In this article, we report a case of subdural hygroma in an infant after cranial vault remodeling procedure. Subdural hygroma is a known complication following head injuries and represents 5% to 20% of posttraumatic intracranial mass lesions. However, subdural hygroma developing after a cranial procedure is rare and has not been reported in the literature. Identification of the complication, close monitoring of the change in subdural fluid volume, and tapping of the fluid through the craniotomy site if indicated form the mainstay of management of subdural hygroma that develops after cranial vault remodeling surgery.

Invasive aspergillosis presenting as swelling of the buccal mucosa in an immunocompetent individual.

Fungi are ubiquitous in nature but have low virulence and cause disease usually when the host defenses are compromised. Fungal infections of the central nervous system are rare and are usually seen in immunocompromised patients. However, in recent years, there has been an increase in the number of central nervous system fungal infections in immunocompetent individuals. Intracranial fungal granulomas are rare space-occupying lesions. Among these, Aspergillus granuloma is the most common. Craniocerebral involvement by aspergillosis usually occurs via the hematogenous route or through contiguous spread from the paranasal sinuses. Predominant symptoms associated with cranial fungal granuloma include headache, vomiting, proptosis, and visual disturbances. Common signs include papilledema, cranial neuropathy, hemiparesis, and meningismus. We present a case of invasive Aspergillus granuloma in an immunocompetent individual, who presented with a palpable mass in the buccal mucosa following removal of an impacted mandibular third molar but with no other characteristic signs and symptoms of invasive fungal granuloma. To our knowledge, there is no documentation of aspergillosis presenting as a swelling in the buccal mucosa. Unexplained swellings in the buccal mucosa should be viewed with a high degree of suspicion and investigated thoroughly at the earliest.

Imaging spectrum of hemangioma and vascular malformations of the head and neck in children and adolescents.

Vascular lesions of the head and neck region in children constitute an interesting group of lesions that benefit immensely from imaging techniques. Imaging is essential for identification, characterization, and delineation of the extent of lesion and subsequent follow-up. Infantile hemangiomas, which are vascular tumors with a specific evolution pattern, constitute a large majority of these lesions. On the other hand, there are vascular malformations, which are anomalies of the vascular system, consisting of a range of vascular tissues associated with various flow patterns. When diagnosis is clinically evident, imaging should utilize non-radiation techniques and address the issues necessary for management. Timing and interpretation of imaging methods employed in assessing childhood vascular lesion should also take into consideration the natural history so that imaging is performed to address a specific question. This review highlights the typical appearance of a hemangioma and a group of vascular malformations of the head and neck. For descriptive purpose, an attempt has been made to group lesions into specific subsites, with each one having specific clinical significance. Cases included illustrate the spectrum of the disease ranging from classical form in young children to slightly differing manifestations of the disease in adolescents and adults. The illustrations also provide a novel way of presenting image data using volume-rendering techniques of 3D data. Multi-modality team interaction and management strategies of these complex lesions are also emphasized.