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.

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.

Comparative Study Between Post Aural Microscopic and Transcanal Endoscopic Tympanoplasty.

Chronic otitis media, inactive mucosal disease needs surgical treatment for complete relief from symptoms like hearing loss and discharging ear. There are various surgical approaches mentioned in literature; among which postauricular microscopic tympanoplasty is the most commonly used. With optics advancements, endoscopic surgeries are gaining more popularity due to reduced operative time, less post-operative pain, better cosmesis and reduced hospital stay. To study the clinical profile of patients with chronic otitis media inactive mucosal disease and compare conventional postauricular microscopic tympanoplasty to transcanal endoscopic tympanoplasty on the basis of operative time, postoperative pain, subjective cosmesis, postoperative complications and postoperative hearing gain. 60 patients of chronic otitis media inactive mucosal type, coming in our out-patient department over 2 years and willing to participate were taken for surgery. Patients were divided into 2 groups of 30 each by computerized random technique. Group A underwent conventional postauricular microscopic tympanoplasty and Group B underwent transcanal endoscopic tympanoplasty. Patients were evaluated on the basis of intraoperative time, postoperative pain score, postoperative complications, subjective cosmesis and postoperative hearing gain. Tympanoplasty by transcanal endoscopic approach had better outcomes in terms of less intraoperative time, less postoperative pain, less postoperative complications, and better subjective cosmetic outcome. Postoperative hearing gain (ABG) in both the groups was similar. Endoscopic tympanoplasty has many advantages over microscopic tympanoplasty as it is a natural access point to tympanic membrane and middle ear cleft. It preserves most of normal anatomy by minimizing dissection of bone and soft tissue. It is possible to obtain a wide angle and a magnified view of the operating field using endoscope with minimum manipulation. Therefore endoscope can be a good alternative of microscope for tympanoplasty.

Spreader Graft Placement: An Effective Procedure for Alleviation of Internal Nasal Valve Collapse.

PURPOSE: The internal nasal valve (INV) is one of the most commonly involved areas in patients with nasal obstruction, and surgeries such as turbinate reduction and septal recontouring affect the physiology of the nasal valve area. With this concept, a cohort study was conducted to evaluate spreader graft's effectiveness in recontouring INV and relieving nasal obstruction. MATERIALS AND METHODS: A prospective cohort study was performed, including patients with nasal obstruction with INV involvement. To quantify and compare the amount of nasal obstruction, Gertner Metal Plate (GMP) was used, and to assess the relief in associated symptoms, the Sino-Nasal Outcome Test (SNOT-22) was taken into consideration. GMP and SNOT 22 were performed preoperatively and postoperatively at the 1st, 3rd, and 6th months, and the data obtained were analyzed by SPSS 22 software using paired t-tests. The postoperative broadening of the nasal dorsum and patient satisfaction with the surgical outcome were also assessed using the visual analog scale . RESULTS: A total of 38 patients were included, with 28 males and 10 females. The data obtained were analyzed by using paired t-tests. Improvement in GMP assessment showed that t = 10.392305, 13.391485, and 15.985243 at the 1st, 3rd, and 6th months, respectively, with an overall P ≤ .00001 and relief in associated symptoms assessed by SNOT 22 computed t = 12.24228, 15.824486, and 18.046395 at the 1st, 3rd, and 6th month, respectively, with an overall P ≤ .00001. A total of 81.57% of patients did not perceive significant nasal dorsum broadening, and 86.84% of patients were highly satisfied by the surgical outcome based on the visual analog scale. CONCLUSION: We conclude that in patients with nasal obstruction associated with INV involvement, spreader grafting provides rapid relief of nasal obstruction and associated symptoms, does not cause any appreciable broadening, and provides a high degree of patient satisfaction. Hence, it should be preferred over septal recontouring and turbinate reduction.