Neurotization of the human cornea - A comprehensive review and an interim report.

We present a comprehensive review of existing literature on surgical corneal neurotization (SCN) as a treatment modality for neurotrophic keratopathy (NK) with an interim report of seven cases where SCN was performed using the indirect approach and followed up till 18 months postoperatively to look for improvement in ocular surface, corneal sensations, and nerve regeneration by using in vivo confocal microscopy (IVCM). A literature search was performed for publications with keywords "corneal nerves," "neurotization," "esthesiometry," "corneal anesthesia," and "neurotrophic keratopathy." All literature available till December 31, 2020 was reviewed and included to describe NK and its management options, particularly SCN. NK is associated with absent or reduced corneal sensations and is managed using a step-ladder algorithm ranging from medical management for symptomatic relief to surgical corneal neurotization. Both direct and indirect approaches of SCN have a favorable outcome with reduced surgical morbidity in the indirect approach using sural nerve graft. Post neurotization, corneal sensation recovery may take up to 3-6 months, while nerve regeneration on confocal microscopy can take as long as 6 months-1 year.

Solitary Fibrous Tumors of the Lacrimal Drainage System With Variable Orbital and Sinonasal Extensions: Combined External and Endoscopic Surgical Approach.

PURPOSE: To report techniques and outcomes of a combined external and endoscopic surgical approach in the management of solitary fibrous tumors of the lacrimal drainage system with variable orbital and sinonasal extensions. METHODS: Biopsy proven cases of solitary fibrous tumors of the lacrimal drainage system involving the lacrimal sac and the nasolacrimal ducts with an orbital, sinonasal, or intranasal extension were studied. Parameters assessed include patient demographics, clinical presentation and course, operative techniques, complications, postoperative adjuvant therapies and outcomes. RESULTS: The technique is described in 3 patients. Two patients had massive orbital extension and one had gross sinonasal extension. Nasolacrimal duct extension was involved in all the patients with intranasal extension in 2 patients. External approach was used to access the lacrimal sac and the orbital components while the endoscopic approach was used to assess the orbital clearance and manage the sinonasal extension and the nasolacrimal duct excision up to the inferior meatus. Following complete excision, additional biopsies were performed from the adjacent bones and sinonasal tissues. A detailed histopathology with immunohistochemistry is essential for not only the diagnosis but also to assess the margin clearance. There were no major postoperative complications. All the patients were advised for postoperative adjuvant external beam radiotherapy. At the last follow-up, none of the patients had any clinical or endoscopic evidence of a recurrence. CONCLUSIONS: A combined external and endoscopic approach en-block excision is most suitable management modality for solitary fibrous tumors involving the lacrimal sac and the nasolacrimal ducts with orbital and sinonasal extension.

Interactive navigation-guided ophthalmic plastic surgery: the techniques and utility of 3-dimensional navigation.

OBJECTIVE: To demonstrate the techniques and utility of 3-dimensional reconstruction (3DR) of the target pathologies for subsequent navigation guidance in ophthalmic plastic surgery. DESIGN: Prospective interventional case series. METHODS: Stereotactic surgeries using 3D reconstruction of target lesions as the intraoperative image-guiding tool were performed in 5 patients with varied etiopathologies. All the surgeries were performed using the intraoperative image-guided StealthStation system in the electromagnetic mode. 3DR was performed using StealthStation 3D model software. The utility of 3D reconstruction for extensive orbital mass lesions, large orbital fractures, intraconal foreign body, and delineation of perilesional intricate structures was studied. The intraoperative ease and usefulness for the navigation of a 3D lesion at crucial phases of the surgery were noted. RESULTS: Intraoperative geometric localization of the 3D lesions was found to be enhanced and precise. 3D reconstruction of the lesion along with the major vessels and nerves in the vicinity helped the surgeon to prevent potential injuries to these structures. The fracture defects could be navigated in a 3D plane and this helped in moderate customization of the implants intraoperatively. Foreign body located in difficult access positions could be accurately targeted for geometric localization before safe retrieval. Detailed preoperative 3D reconstruction by the surgeon was found to be beneficial for successful outcomes. CONCLUSIONS: Three-dimensional navigation is very useful in providing detailed anatomical delineation of the targets and enhances the precision in certain complex cases in ophthalmic plastic surgery.

Interactive navigation-guided ophthalmic plastic surgery: assessment of optical versus electromagnetic modes and role of dynamic reference frame location using navigation-enabled human skulls.

AIM: The aim of this study was to assess the anatomical accuracy of navigation technology in localizing defined anatomic landmarks within the orbit with respect to type of technology (optical versus electromagnetic systems) and position of the dynamic reference marker on the skull (vertex, temporal, parietal, and mastoid) using in vitro navigation-enabled human skulls. The role of this model as a possible learning tool for anatomicoradiological correlations was also assessed. METHODS: Computed tomography (CT) scans were performed on three cadaveric human skulls using the standard image-guidance acquisition protocols. Thirty-five anatomical landmarks were identified for stereotactic navigation using the image-guided StealthStation S7™ in both electromagnetic and optical modes. Three outcome measures studied were accuracy of anatomical localization and its repeatability, comparisons between the electromagnetic and optical modes in assessing radiological accuracy, and the efficacy of dynamic reference frame (DRF) at different locations on the skull. RESULTS: The geometric localization of all the identified anatomical landmarks could be achieved accurately. The Cohen's kappa agreements between the surgeons were found to be perfect (kappa =0.941) at all predetermined points. There was no difference in anatomical localization between the optical and electromagnetic modes (P≤0.001). Precision for radiological identification did not differ with various positions of the DRF. Skulls with intact anatomical details and careful CT image acquisitions were found to be stereotactically useful. CONCLUSION: Accuracy of anatomic localization within the orbit with navigation technology is equal with optical and electromagnetic system. The location of DRF does not affect the accuracy. Navigation-enabled skull models can be potentially useful as teaching tools for achieving the accurate radiological orientation of orbital and periorbital structures.

Functional and esthetic rehabilitation in a partially edentulous patient: a case report.

A young male patient reported with forwardly placed mandible and partially edentulous upper and lower jaws. Patient's chief concern was towards his abnormal facial profile and difficulty in mastication. This case report describes various procedures performed to rehabilitate the patient functionally and esthetically. The treatment plan included Onlay bone grafting of mandible using iliac crest, body osteotomy of edentulous mandible and implant retained overdenture.

An unusual approach to retrieve right mandibular canine tooth, displaced into submandibular space following fracture mandible, using c-arm.

The purpose of this article is to present an unusual approach to retrieve a displaced tooth. In our patient the right mandibular canine was displaced into the right submandibular space during trauma. The displaced tooth was localized intraoperatively by the use of C-Arm radiography and retrieved surgically.