Optogenetics: Illuminating the Future of Hearing Restoration and Understanding Auditory Perception.

Hearing loss is a prevalent sensory impairment significantly affecting communication and quality of life. Traditional approaches for hearing restoration, such as cochlear implants, have limitations in frequency resolution and spatial selectivity. Optogenetics, an emerging field utilizing light-sensitive proteins, offers a promising avenue for addressing these limitations and revolutionizing hearing rehabilitation. This review explores the methods of introducing Channelrhodopsin- 2 (ChR2), a key light-sensitive protein, into cochlear cells to enable optogenetic stimulation. Viral- mediated gene delivery is a widely employed technique in optogenetics. Selecting a suitable viral vector, such as adeno-associated viruses (AAV), is crucial in efficient gene delivery to cochlear cells. The ChR2 gene is inserted into the viral vector through molecular cloning techniques, and the resulting viral vector is introduced into cochlear cells via direct injection or round window membrane delivery. This allows for the expression of ChR2 and subsequent light sensitivity in targeted cells. Alternatively, direct cell transfection offers a non-viral approach for ChR2 delivery. The ChR2 gene is cloned into a plasmid vector, which is then combined with transfection agents like liposomes or nanoparticles. This mixture is applied to cochlear cells, facilitating the entry of the plasmid DNA into the target cells and enabling ChR2 expression. Optogenetic stimulation using ChR2 allows for precise and selective activation of specific neurons in response to light, potentially overcoming the limitations of current auditory prostheses. Moreover, optogenetics has broader implications in understanding the neural circuits involved in auditory processing and behavior. The combination of optogenetics and gene delivery techniques provides a promising avenue for improving hearing restoration strategies, offering the potential for enhanced frequency resolution, spatial selectivity, and improved auditory perception.

Isolated Papillary Thyroid Carcinoma of the Pyramidal Lobe: A Case Report and Review of Literature.

The pyramidal lobe (PL) represents an embryological remnant of the thyroglossal duct. A solitary focus of papillary thyroid carcinoma (PTC) of the PL of thyroid gland is a rare entity. We present a case of a 33-year-old woman with PTC of the PL with lymph nodal involvement and further discuss the lines of surgical management for primary PTC arising from the PL of thyroid gland.

Radioactive Iodine in Differentiated Carcinoma of Thyroid: An Overview.

Thyroid cancer is the fifth most prevalent cancer in women and the fastest-growing malignancy. Although surgery is still the basis of treatment, internal radiation therapy [Brachytherapy] with radioactive iodine-131, which functions by releasing beta particles with low tissue penetration and causing DNA damage, is also a potential option. The three basic aims of RAI therapy in well-differentiated thyroid tumors are ablation of the remnant, adjuvant therapy, and disease management. Radioactive iodine dose is selected in one of two ways, empiric and dosimetric, which relies on numerous criteria. The dosage for ablation is 30-100 mCi, 30-150 mCi for adjuvant therapy, and 100-200 mCi for treatment. The RAI treatment effectively aids in the treatment to achieve complete removal of the disease and increase survival. The present review intends to emphasize the significance of radioactive iodine in the management of differentiated thyroid cancer and put forward the current breakthroughs in therapy.

Nuclear Imaging Modalities in the Diagnosis and Management of Thyroid Cancer.

In this review we have brought forward various nuclear imaging modalities used in the diagnosis, staging, and management of thyroid cancer. Thyroid cancer is the most common endocrine malignancy, accounting for approximately 3% of all new cancer diagnoses. Nuclear imaging plays an important role in the evaluation of thyroid cancer, and the use of radioiodine imaging, FDG imaging, and somatostatin receptor imaging are all valuable tools in the management of this disease. Radioiodine imaging involves the use of Iodine-123 [I-123] or Iodine-131 [I-131] to evaluate thyroid function and detect thyroid cancer. I-123 is a gamma-emitting isotope that is used in thyroid imaging to evaluate thyroid function and detect thyroid nodules. I-131 is a beta-emitting isotope that is used for the treatment of thyroid cancer. Radioiodine imaging is used to detect the presence of thyroid nodules and evaluate thyroid function. FDG imaging is a PET imaging modality that is used to evaluate the metabolic activity of thyroid cancer cells. FDG is a glucose analogue that is taken up by cells that are metabolically active, such as cancer cells. FDG PET/CT can detect primary thyroid cancer and metastatic disease, including lymph nodes and distant metastases. FDG PET/CT is also used to monitor treatment response and detect the recurrence of thyroid cancer. Somatostatin receptor imaging involves the use of radiolabeled somatostatin analogues to detect neuroendocrine tumors, including thyroid cancer. Radiolabeled somatostatin analogues, such as Indium-111 octreotide or Gallium-68 DOTATATE, are administered to the patient, and a gamma camera is used to detect areas of uptake. Somatostatin receptor imaging is highly sensitive and specific for the detection of metastatic thyroid cancer. Methods: A comprehensive search of relevant literature was done using online databases of PubMed, Embase, and Cochrane Library using the keywords "thyroid cancer," "nuclear imaging," "radioiodine imaging," "FDG PET/CT," and "somatostatin receptor imaging" to identify relevant studies to be included in this review. Conclusion: Nuclear imaging plays an important role in the diagnosis, staging, and management of thyroid cancer. The use of radioiodine imaging, thyroglobulin imaging, FDG imaging, and somatostatin receptor imaging are all valuable tools in the evaluation of thyroid cancer. With further research and development, nuclear imaging techniques have the potential to improve the diagnosis and management of thyroid cancer and other endocrine malignancies.

An Easy to use Periosteal Flap for Cochlear Implantation: Experience from a Tertiary Care Centre.

This report describes a novel and easy periosteal flap design for cochlear implantation. This technique has been used in 37 patients between June 2019 and August 2020. The patients have been followed up for a period of 2 months to 15 months. There were no flap related complications attributed to this flap. There was no wound hematoma, wound breakdown or implant migration. The flap design is safe, easy, less time consuming and results in better coverage of the receiver stimulator unit without any tension.

Endoscope Assisted Combined Drainage of Sino-Orbital Abscess: Technique Revisited.

Orbital complications of acute rhinosinusitis may present with painful proptosis and ophthalmoplegia. Surgical management, when required comprises of endonasal endoscopic sinus clearance with or without external orbital abscess drainage. External drainage involves blind dissection and carries a risk of iatrogenic injury to periorbital structures. We describe a novel technique of endoscope guided orbital abscess drainage under direct visualisation via the external incision site. Patients with orbital cellulitis secondary to rhinosinusitis and planned for surgical intervention were recruited. After endonasal endoscopic sinus surgery, the orbital abscess cavity was opened and an endoscope was inserted externally. The cavity was examined; loculi were opened under direct visualisation till drainage was complete. This procedure was performed in seven patients with a successful outcome. The mean time to resolution was 1.5 months (36.4 ± 18.2 days). None of the patients had any recurrence or residual disease on follow up. In addition, in two cases with obstructed sinus drainage and "walling off" of frontal sinus, visualisation of the instrument placed in the drained abscess cavity via endo-nasally inserted endoscope confirmed the re-establishment of continuity of sinus opening. This approach may allow the surgeon to drain multiloculated abscess completely under direct visualization while minimising iatrogenic damage to periorbital structures. Real time display using endoscopic camera on the monitor screen also serves as a teaching and training tool during the procedure. Technique utilises the existing endoscopic set-up without the need for additional instrumentation.

COVID-19 Associated Rhino-Orbital-Cerebral Mucormycosis: A Proposed Classification and Treatment Strategies.

OBJECTIVES: Mucormycosis is a rare fungal disease, which was known to affect only immunocompromised hosts, but during the COVID-19 pandemic, a surge in the cases of rhino- orbital-cerebral mucormycosis have been reported; however, the cause is still unknown. As the disease was a rare entity, there was no classification considering the spread and proper management at various stages. METHODS: Extensive literature search with the terms "mucormycosis," "invasive fungal sinusitis," "COVID-19 associated mucormycosis," and "mucormycosis in COVID-19" was conducted on Pubmed, Scopus, and Embase database, taking into consideration case histories, revealing the site of involvement and treatment based on the disease's extent. RESULTS: Relevant articles were analyzed, and it was found that there is no specific classification of the disease entity and no proper surgical and medical management guidelines to date, Conclusion: This review is an attempt to elaborate on the pathophysiology of mucormycosis and its spread and propose a classification that will help determine policies for the control and prevention of complications, morbidity, and mortality.

The relevance of extra-nodal natural killer/T-cell lymphoma to the oral health care providers- A clinical review with case report.

Lymphomas are the second most common malignancy in the oral cavity after squamous cell carcinoma. Non-specific clinical presentation of lymphoma mimics the other common oral pathologies thereby; delaying its diagnosis, ensuing definitive treatment, and leading to a guarded prognosis. The present clinical review and accompanying case report highlights the clinical presentation, diagnostic challenges, progression, manifestations, and holistic management of a rare extra-nodal, nasal variant of Natural Killer T-cell lymphoma and underscores the importance of interdisciplinary coordination in the overall management of this aggressive tumor.

COVID-19-associated mucormycosis: An updated systematic review of literature.

In its wake, the COVID-19 pandemic has ushered in a surge in the number of cases of mucormycosis. Most cases are temporally linked to COVID-19; hence, the entity is described as COVID-19-associated mucormycosis (CAM). The present systematic review was undertaken to provide an up-to-date summary of the hitherto available literature on CAM. PubMed, Scopus and Google Scholar databases were systematically searched using appropriate keywords till 14 May 2021, to identify case reports/case series pertaining to mucormycosis in patients with COVID-19. Relevant data extracted included demographic characteristics, comorbidity profile, clinical category of mucormycosis, glucocorticoid use, treatment offered and patient outcome. We identified 30 case reports/case series, pooling data retrieved from 99 patients with CAM. Most cases were reported from India (72%). The majority of the patients was male (78%) and had diabetes mellitus (85%). A prior history of COVID-19 was present in 37% patients with mucormycosis developing after an initial recovery. The median time interval between COVID-19 diagnosis and the first evidence of mucormycosis infection or CAM diagnosis was 15 days. Glucocorticoid use was reported in 85% of cases. Rhino-orbital mucormycosis was most common (42%), followed by rhino-orbito-cerebral mucormycosis (24%). Pulmonary mucormycosis was observed in 10 patients (10%). The mortality rate was 34%; the use of adjunct surgery, which was undertaken in 81% of patients, was associated with better clinical outcomes (p < .001). In conclusion, CAM is an emerging problem necessitating increased vigilance in COVID-19 patients, even those who have recovered. CAM portends a poor prognosis and warrants early diagnosis and treatment.

A Novel Technique of Draping for Otologic Surgery: Mitigation of Aerosol Generation During Covid Pandemic.

The surgical procedures in the temporal bone have the potential to generate aerosols which could affect the health care personnel. An innovative way to avoid aerosolization during ear surgery has been highlighted in this manuscript.