Presentation of Arteria Lusoria with Non Recurent Laryngeal Nerve.

Non-recurrent laryngeal nerve (NRLN) is an anatomic variation seen in about 0.52-0.7% patients, generally on right side. It exits the vagus nerve having a direct route to the larynx, unlike usual recurrent laryngeal nerve, supplying intrinsic laryngeal muscles except cricothyroid. It is sited over left side on extremely rare occasions, that is, 0.04% of the cases. Some cases of NRLN co-exists with aberrant right subclavian artery which courses behind the esophagus, also known as 'arteria lusoria'. Here we present a case of 60-years old patient, diagnosed as goiter presented to us in june 2023 at the department of head and neck surgery at a tertiary care setup of Karachi Pakistan. Intra-operatively, non-recurrent nerve was encountered, whose association was found with arteria lusoria, observed in pre-operative CT-scan. The nerve was saved and no post-operative complications were seen in patient. The association of arteria lusoria in this case emphasize its importance in predicting NRLN via pre-operative imaging techniques which can prevent its injury intra-operatively.

Solitary Fibrous Tumor of Nasal Cavity: A Case Report.

Solitary fibrous tumors (SFTs) belonging to a distinct group of mesenchymal tumors, was originally described by Klemper and Rabin in the pleura in year 1931. However, it can also be extra-pleural in origin. With tongue being the most common site involved in this region, epiglottis, larynx, thyroid, external auditory canal, lacrimal sac, hypoglossal nerve, parotid gland, sublingual gland, Para pharyngeal space, nasopharynx, scalp, gingiva, orbit and infratemporal fossa as well as paranasal sinuses and nasal cavities can also get involved. But SFTs involving nasal cavities and nasopharynx are quite uncommon, accounting for < 0.1% of all Sino-nasal neoplasms. Until now there have only been 40 cases of nasal SFT reported in literature. We report the case of an extraserosa solitary fibrous tumor arising from the nasal cavity with extension to the sphenoid sinus, a much rarer presentation of its type. Our case report is one of its type, emphasizing the need conducting further studies on the nature and management of the disease.

Syndromic Piere Robbin Sequence- A Rare Presentation in Association with Multiple Heart Defects and Type III Stickler Syndrome.

Pierre Robin Sequence (PRS), a rare congenital disorder, is a triad of micrognathia, glossoptosis, and tongue based airway obstruction (TBSO). It may occur as isolated anomaly (iPRS) or as a part of a syndrome (sPRS), like that seen in association with Stickler Syndrome. Approximately 20% of children with PRS have congenital heart diseases. To the best of our knowledge this case of a one-day old infant is the first one to be reported as having two heart defects; patent ductus arteriosus and patent foramen ovale in Pierre Robbin Sequence child.

Successful management of a difficult airway in a case of advanced thyroid cancer.

Papillary thyroid carcinoma is the most prevalent endocrine malignancy of the head and neck region. It makes up to 80% of all thyroid cancers, and has a 10-year survival rate of up to 95%. Differentiated thyroid carcinomas have good prognosis after a complete surgical extirpation as long as it is not associated with invasion of the surrounding structures. The advanced papillary thyroid carcinoma can invade the neighbouring structures of the thyroid gland, such as strap muscles, recurrent laryngeal nerve, trachea, oesophagus, larynx, pharynx, and carotids. Whenever papillary thyroid carcinoma is associated with invasion of aerodigestive tract it is difficult to excise the tumour. We report a patient with stage IV invasive papillary thyroid carcinomas as per Shin Staging system. The surgery was deferred from several hospitals considering the advanced stage of the disease with tracheal extension making it a problematic airway for both the anaesthesiologist and the operating surgeon. The patient underwent total thyroidectomy, modified radical neck dissection, tracheal resection, and primary anastomosis. Successful intubation was done with video laryngoscopy. Intermittent apnoea technique was used for ventilation during the repair of posterior tracheal wall. The patient was extubated on the table and shifted to the recovery room. The histopathologic diagnosis was reported as papillary thyroid carcinoma classic variant with tracheal invasion.

Implication of stem cells and platelet rich plasma in otolaryngology, head and neck surgical procedures.

Human body has a set of unspecialized cells called as stem cells that have the ability to generate cells of specialized function. Volume of fractionated plasma extracted from autologous blood is termed as Platelet-rich plasma (PRP) that is rich in several growth factors. Both have shown effective results in the field of regenerative medicine. Physiologically, platelets are the first cells to concentrate at the site of tissue damage, therefore application of PRP in diverse surgical procedures enhances bone and soft tissue healing; this same phenomenon is currently being used in otology, head and neck flap surgery and yielding miraculous outcomes. The perspective role of stem cells in regenerative medicine is wrapped in its loosely arranged DNA with working genes; a similar concept is being worked upon in different ENT procedures with groundbreaking results. But still, the data is scarce and there is a dire need for clinical trials, and large population-level studies to further formulate the guidelines on basis of proven evidence.

High-riding innominate artery in the neck: A hazardous presentation during surgery.

Aberrant innominate artery lying high in the neck is a rare entity that can be encountered intraoperatively during midline neck surgeries such as thyroidectomy and tracheostomy. Surgeons should be mindful of this entity as injury to the artery can lead to life-threatening haemorrhage. We report a case of a 40 year old female in whom an aberrant innominate artery was identified high in the neck, while performing a total thyroidectomy.

Unilateral Thyroid Lobectomy as Day Care Procedure: A Cross Sectional Study with Literature Review on the Safety and Cost Effectiveness

Abstract Introduction Thyroid nodules are common globally in almost one fifth of the adult population. The gold standard treatment for thyroid nodule is thyroid lobectomy or total thyroidectomy depending upon the diagnosis. Thyroidectomy has a few known complications but, as per the ATA consensus statement, it is a safe surgery to be done as a day care procedure. Objective To access the feasibility and safety of thyroid lobectomy as a day care surgery and its effect on decreasing overall financial burdens. Methods This retrospective chart review was done from 2006 to 2022. A total of 736 patients underwent thyroid lobectomy among which only 56 were done as day care surgery. Data analysis was done using the IBM SPSS Statistics for Windows, Version 23.0 (IBM Corp., Armonk, NY, USA). Results A total of 40% of the population was male. The mean age of the study population was 42 years. Bethesda II was the most encountered diagnosis, with a rate of 69%. The majority of patients were discharged after 6 hours of postoperative observation. The only complication encountered was seroma, which was seen in two patients. Conclusion Thyroid lobectomy appears to be a safe procedure with a drastic difference in overall cost as a day care procedure. We recommend switching the practice of inpatient thyroid lobectomy to a day care procedure in carefully selected candidates. The major hurdle in day care lobectomy can be approval from insurance.

Unilateral Thyroid Lobectomy as Day Care Procedure: A Cross Sectional Study with Literature Review on the Safety and Cost Effectiveness.

Introduction Thyroid nodules are common globally in almost one fifth of the adult population. The gold standard treatment for thyroid nodule is thyroid lobectomy or total thyroidectomy depending upon the diagnosis. Thyroidectomy has a few known complications but, as per the ATA consensus statement, it is a safe surgery to be done as a day care procedure. Objective To access the feasibility and safety of thyroid lobectomy as a day care surgery and its effect on decreasing overall financial burdens. Methods This retrospective chart review was done from 2006 to 2022. A total of 736 patients underwent thyroid lobectomy among which only 56 were done as day care surgery. Data analysis was done using the IBM SPSS Statistics for Windows, Version 23.0 (IBM Corp., Armonk, NY, USA). Results A total of 40% of the population was male. The mean age of the study population was 42 years. Bethesda II was the most encountered diagnosis, with a rate of 69%. The majority of patients were discharged after 6 hours of postoperative observation. The only complication encountered was seroma, which was seen in two patients. Conclusion Thyroid lobectomy appears to be a safe procedure with a drastic difference in overall cost as a day care procedure. We recommend switching the practice of inpatient thyroid lobectomy to a day care procedure in carefully selected candidates. The major hurdle in day care lobectomy can be approval from insurance.

Frequency of Thyroid Gland Invasion by Laryngeal Squamous Cell Carcinoma: The Role of Subglottic Extension

Abstract Introduction Management of the thyroid gland during laryngectomy has been controversial. The primary tumor may invade the thyroid gland by direct invasion or lymphovascular spread. Hypothyroidism and hypoparathyroidism are potential risks when lobectomy or total thyroidectomy are performed simultaneously. Objective To report the frequency of thyroid gland involvement by primary laryngeal squamous cell carcinoma in patients undergoing laryngectomy and to identify possible risk factors for thyroid gland involvement so that judicious excision of thyroid gland can be attained. Methods We performed a retrospective review of 9 years. Data was collected from medical records of patients dated from December 2009 to October 2018. All patients with laryngeal cancer who underwent laryngectomy with lobectomy or total thyroidectomy were included in the present study. Results We reviewed 151 laryngectomy records. A total of 130 surgeries included the thyroid gland with the excised specimen and were available for analysis. There were 124 males and 6 females. The mean age was 59.4 years old. The glottis was the most common subsite involved, in 70 patients, followed by 38 transglottic, 16 supraglottic and 03 subglottic tumors. On histology, 12 out of 130 excised thyroid glands were involved by squamous cell carcinoma. Only subglottic involvement (p = 0.01) was significantly associated with thyroid gland invasion (TGI). Type of laryngectomy, subsite of the primary tumor, thyroid cartilage involvement, neck nodal metastases, and perineural and lymphatic invasion by the primary tumor were not associated with TGI. Conclusion Only subglottic involvement is associated with TGI; therefore, preoperative and intraoperative assessment is necessary prior to considering excision of the thyroid gland.

Frequency of Thyroid Gland Invasion by Laryngeal Squamous Cell Carcinoma: The Role of Subglottic Extension.

Introduction Management of the thyroid gland during laryngectomy has been controversial. The primary tumor may invade the thyroid gland by direct invasion or lymphovascular spread. Hypothyroidism and hypoparathyroidism are potential risks when lobectomy or total thyroidectomy are performed simultaneously. Objective To report the frequency of thyroid gland involvement by primary laryngeal squamous cell carcinoma in patients undergoing laryngectomy and to identify possible risk factors for thyroid gland involvement so that judicious excision of thyroid gland can be attained. Methods We performed a retrospective review of 9 years. Data was collected from medical records of patients dated from December 2009 to October 2018. All patients with laryngeal cancer who underwent laryngectomy with lobectomy or total thyroidectomy were included in the present study. Results We reviewed 151 laryngectomy records. A total of 130 surgeries included the thyroid gland with the excised specimen and were available for analysis. There were 124 males and 6 females. The mean age was 59.4 years old. The glottis was the most common subsite involved, in 70 patients, followed by 38 transglottic, 16 supraglottic and 03 subglottic tumors. On histology, 12 out of 130 excised thyroid glands were involved by squamous cell carcinoma. Only subglottic involvement ( p = 0.01) was significantly associated with thyroid gland invasion (TGI). Type of laryngectomy, subsite of the primary tumor, thyroid cartilage involvement, neck nodal metastases, and perineural and lymphatic invasion by the primary tumor were not associated with TGI. Conclusion Only subglottic involvement is associated with TGI; therefore, preoperative and intraoperative assessment is necessary prior to considering excision of the thyroid gland.

A novel systematic byte substitution method to design strong bijective substitution box (S-box) using piece-wise-linear chaotic map.

Cryptography deals with designing practical mathematical algorithms having the two primitive elements of confusion and diffusion. The security of encrypted data is highly dependent on these two primitive elements and a key. S-box is the nonlinear component present in a symmetric encryption algorithm that provides confusion. A cryptographically strong bijective S-box structure in cryptosystem ensures near-optimal resistance against cryptanalytic attacks. It provides uncertainty and nonlinearity that ensures high confidentiality and security against cryptanalysis attacks. The nonlinearity of an S-box is highly dependent on the dispersal of input data using an S-box. Cryptographic performance criteria of chaos-based S-boxes are worse than algebraic S-box design methods, especially differential probability. This article reports a novel approach to design an 8 × 8 S-box using chaos and randomization using dispersion property to S-box cryptographic properties, especially differential probability. The randomization using dispersion property is introduced within the design loop to achieve low differential uniformity possibly. Two steps are involved in generating the proposed S-box. In the first step, a piecewise linear chaotic map (PWLCM) is utilized to generate initial S-box positions. Generally, the dispersion property is a post-processing technique that measures maximum nonlinearity in a given random sequence. However, in the second step, the concept is carefully reverse engineered, and the dispersion property is used within the design loop for systematic dispersal of input substituting sequence. The proposed controlled randomization changes the probability distribution statistics of S-box's differentials. The proposed methodology systematically substitutes the S-box positions that cause output differences to recur for a given input difference. The proposed S-box is analyzed using well-established and well-known statistical cryptographic criteria of nonlinearity, strict avalanche criteria (SAC), bit independence criteria (BIC), differential probability, and linear probability. Further, the S-box's boomerang connectivity table (BCT) is generated to analyze its strength against boomerang attack. Boomerang is a relatively new attacking framework for cryptosystem. The proposed S-box is compared with the state-of-the-art latest related publications. Results show that the proposed S-box achieves an upper bound of cryptographic properties, especially differential probability. This work hypothesizes that highly dispersive hamming distances at output difference, generated a systematic S-box. The mixing property of chaos generated trajectories utilized for decimal mapping. To test the randomness of generated chaotic trajectories, a cryptographically secure pseudo-random sequence was generated using a chaotic map that was tested using the National Institute of Standards and Technology (NIST) NIST-800-22 test suit.

Ethical Dilemmas in the Management of Head and Neck Cancers in the Era of the COVID-19 Pandemic.

Coronavirus disease 2019 (COVID-19) has emerged as an unforeseen challenge for head and neck cancer care providers. A similar challenge is also faced by other oncological fields, but the severity of this challenge is highest in otolaryngology because of the need for additional precautionary measures and curbs on the possibility of aerosol forming interventions related to the upper aerodigestive tract. In this narrative review, provision of ethical and consistent care on moral and professional grounds to head and neck cancer patients during the pandemic are discussed for professionals who provide head and neck oncology care.

The Utility of Frozen Sections in the Evaluation of Clear Margins in Oral Squamous Cell Carcinomas: A Cross-Sectional Study From a Tertiary Care Center.

Background and objective Head and neck cancers are prevalent in Pakistan. Oral squamous cell carcinomas are primarily treated via surgical removal, and complete surgical resection is the paramount prognostic factor. A resection margin of 5 mm on the final histopathology report has been accepted as adequate in the existing literature. Negative margins on the frozen section do not guarantee adequate disease-free resections on the final histopathology report. In this study, we aimed to ascertain how accurately tumor-free margins can be detected on frozen sections, which are reported intraoperatively compared to permanent sections of the same tissues reported after proper staining in oral squamous cell carcinoma patients. Methods A cross-sectional study was conducted at a tertiary care hospital in Karachi, Pakistan; 94 patients presenting between January and October 2016 were included in this study and a total of 432 tumor margins were assessed. Results Among the total 94 patients included in the study, 79% were male and 21% were female. Buccal mucosa was the most commonly involved subsite (57%), followed by the tongue (25%). The most common T stage was T4 (33%), followed by T2 and T3 at 28% and 21% respectively, while the most common N stage was N0 (55%) followed by N1 at 16% and N2 at 22%. The sensitivity of the frozen section in comparison to the permanent section was found to be 50%, while specificity was calculated to be 99.8%. The positive predictive value was 75% and the negative predictive value was 99.3%. Conclusion The frozen section is a highly useful tool for the evaluation of tumor margins. However, while it has high diagnostic accuracy rates, it can produce altered results and therefore requires high clinical correlation.

Rates of publication of FCPS dissertations in international and national peer-review journals among residents at AKUH; A cross sectional review of 15 years.

OBJECTIVE: To see the rate of publication of postgraduate residents' dissertation. METHODS: The single-centre retrospective cross-sectional study was conducted at the Aga Khan University Hospital, Karachi, and comprised research publications from the residents of the departments of Surgery and Medicine who graduated between 2005 and 2020. The surgical subspecialties included Otolaryngology, Ophthalmology, Dentistry, General Surgery, Orthopaedics, Paediatric Surgery, Urology, Plastic Surgery and Cardiovascular Surgery. Data comprised demographics, current institution, current designation, information on dissertation/paper publication, topic of study, year of completion of dissertation, input from the research department, delay in exam due to incomplete dissertation and whether the paper got published in national or international journal. Data was analysed using SPSS 21. RESULTS: Of the 103 subjects, 70(68%) were males and 33(32%) were females, while 73(70.8%) belonged to surgical specialties and 30(29.2%) were from non-surgical specialties. Of the 22(22.9%) who were able to convert, 12(54.5%) publications were carried by national peer-reviewed journals, while 10(45.4%) were carried by international journals; 9(40.9%) unpaid peer review journals and 13(59.1%) paid journals. Delay in exam due to incomplete dissertation was faced by only 16(16.6%) candidates. CONCLUSIONS: The rate of publication for resident dissertation was found to be low.

The Efficacy of Bethesda System for Prediction of Thyroid Malignancies- A 9 Year Experience from a Tertiary Center.

INTRODUCTION: The best initial investigation for thyroid nodule is fine needle aspiration (FNA). Bethesda System is an international standardized system of reporting thyroid nodules and recommends subsequent management. Every institution should assess the risk of malignancy in each category to avoid unnecessary thyroid surgeries, with this aim we conducted a review at our center to calculate risk of malignancy in each category. MATERIALS AND METHODS: Retrospective 9-year (2009-2018) review of thyroid FNAs done at a tertiary care Centre. The FNA was stratified according to The Bethesda System. Histopathology reports of the operated cases were used to evaluate the cytology for diagnostic accuracy. RESULTS: There were 495 patients who underwent thyroidectomy. The mean age of the cohort was 42.51 +/- 13.2 years and 387 (78.2%) were females. The frequency of Bethesda categories I, II, III, IV, V, and VI were 9.1%, 55.6%, 16.4%, 6.5%, 9.3%, and 3.2% respectively. Malignancy rate in operated thyroid nodules were 37.8%, 8.4%, 33.3%, 50.0%, 89.1%, and 100% for Bethesda categories I to VI, respectively. The sensitivity, specificity, negative predictive value and positive predictive value and their 95% CIs were calculated as 81.30 (73.28 - 87.76%), 77.06 (72.12 - 81.51%), 91.64 (88.3 - 94.1%) and 57.14 (51.79 - 62.33%). The overall diagnostic accuracy was 78.22 (74.12 - 81.95%). CONCLUSIONS: All the Bethesda categories showed greater malignancy risks than other reported studies. Knowledge of local rates of malignancy is important to accurately predict the risk of malignancy even when reported with internationally accepted nomenclature like the Bethesda System.

Numerical Analysis of a Liquid Nitrogen (LN2) Engine for Efficient Energy Conversion.

A liquid fuel that produces no toxic exhaust could help reduce pollution, potentially in urban areas. In this study, a simulation was conducted using the AVL Boost platform, on the use of liquid nitrogen (LN2) in a four-stroke engine. This study is focused on engine performance using directly introduced LN2 and the analysis of related aspects (inlet, outlet, and in-cylinder pressure, temperature, conditions for LN2 evaporation, etc.) that indicate the possible potential for the development of a zero-emission direct injection internal evaporation (DI-IE) LN2 engine. AVL Boost software was uniquely customized to accommodate the simulations, as modeling with LN2 was not available in the standard features. Simulation results, including indicated mean effective pressure (IMEP), effective torque, and power, were compared with similarly sized diesel and gasoline engines running at speeds of up to 1000 rpm. The LN2 injection mass was matched with air intake to evaluate the optimal combination. The simulation results showed that the enthalpy of the aspirated air was sufficient to evaporate and expand the injected amount of LN2 in each cycle, generating the in-cylinder pressure for the power stroke. The IMEP of the LN2 engine was similar to internal combustion engines, and its indicated efficiency was about four times higher (56-62%). The air separation process was 44% efficient in producing the required LN2, making the overall efficiency about 31%.

Role of contrast enhanced computed tomography in assessing cervical lymph node metastases in oral cavity squamous cell carcinoma.

OBJECTIVE: To evaluate the diagnostic accuracy of contrast-enhanced computed tomography scan in detecting cervical nodal metastasis in oral cavity squamous cell carcinoma. METHODS: The retrospective cross-sectional study was conducted at Aga Khan University Hospital, Karachi, Pakistan. and comprised records from January 1, 2015, to October 31, 2016, of patients diagnosed with oral cavity squamous cell carcinoma and who underwent surgical resection of primary tumour along with neck dissection after having a contrast-enhanced computed tomography scan of head and neck. Diagnostic accuracy of the scans was calculated using final histopathology as the gold standard. All scans were reviewed by a consultant radiologist. Data was analysed using SPSS 23. RESULTS: Of the 100 patients whose records were reviewed, 70(70%) were female, 55(55%) had buccal and 32(32%) had tongue cancer.. The scans had sensitivity 83%, specificity 61.7%, positive predictive value 70.9%, negative predictive value 76.3% and overall diagnostic accuracy 73%. CONCLUSIONS: Computed tomography scan was found to be a useful tool for preoperative staging of oral cavity squamous cell carcinoma. However, due to low specificity and negative predictive value, elective neck dissection should still be done in a negative scan for cervical lymph node metastases.

Hypoglossal Nerve Paraganglioma Depicting as Glomus Tumor of Neck.

INTRODUCTION: Paraganglioma are infrequent neuroendocrine tumors that are most commonly found in the carotid body, ganglia of the vagus, jugular and tympanic nerve. Very rarely they can involve other cranial nerves outside the cranial cavity, we present one such case of hypoglossal nerve paraganglioma in neck. CASE REPORT: A 48 years old male presented with 1-month history of right sided stroke and aphasia. Ultrasonography of neck revealed a highly vascular mass on the right side of the neck. CT angiogram confirmed a highly vascular mass arising above the carotid bifurcation. With the working diagnosis of Glomus tumor, he underwent right sided neck exploration, however, intra-operatively tumor was found to be arising from the hypoglossal nerve instead. Surgery was abandoned on basis of the available literature, with only 6 reported cases in the past 54 years. Patient had no immediate post op complications and was sent for cyber knife treatment. After completion of 5 cycles of cyber knife there was a total of 45% reduction in the size of the paraganglioma with the resolution of the patient's symptoms after a follow up of 6 months. CONCLUSION: Hypoglossal nerve paraganglioma is an uncommon tumor of the neck and can be misdiagnosed with the other tumors in this region especially chemodectoma and glomus tumor. The diagnostic criteria and appropriate treatment modalities have not been established due to the rare presentation hence hypoglossal paraganliomas should be kept in mind when Highly vascular neck mass is encountered.

Training in temporal bone surgery: A review of current practices.

The temporal bone consists of complex anatomy, and the presence of various vital structures in close proximity makes the surgery of temporal bone highly challenging. Such a surgery requires years of training under the direct observation of trainers. Over the course of history, different training models have been adopted by experts to help train the young surgeons in this complex procedure. Cadaveric dissections of the temporal bone remains the gold standard in training of residents as the cadavers present the actual anatomical details which the surgeons encounter while operating on patients. However, due to scarcity of available cadavers, their one-time-only usage and high cost of involved in such trainings, experts have developed newer techniques of training, including three-dimensional reconstruction models and virtual reality simulators. Most of the literature on simulation in training of residents focuses on anatomical understanding and development of the surgical technique. There has been significant improvement in these techniques over time. With the addition of haptic feedback in the newer virtual simulation models, simulation has edged closer to basic modules of temporal bone dissection. the current review article was planned to have an overview of the different techniques in detail that are currently being in used.

Screening for malnutrition in oral cavity cancer patients prior to treatment: A cross-sectional study.

This study was conducted to assess the frequency of pre-operative malnourishment in patients being treated for oral cavity squamous cell carcinoma. A retrospective chart review was carried out at the Aga Khan University Hospital, Karachi, on 62 patients. Patients were screened pre-operatively through a standard nutritional assessment tool at the time of admission to assess for malnutrition. Mean age of presentation was 48.34±13.11 years, mean height was 165 ± 8.62cm, weight 66.09±14.98 kg and BMI of 24.09±4.84. Males were 82.3% and 17.7% were females. At the time of admission, a significant number or patients, 12 (19.4%) were prone to malnourishment, while 3 (4.8%) patients were malnourished: Assessment was done by using a standardised nutritional assessment tool.