Neck Masses and Stridor

Define a Neck Mass, including its anatomical boundaries, and list five normal structures that should not be mistaken for a pathological mass.

A Neck Mass is an abnormal lesion identifiable by inspection, palpation, or imaging, located below the mandible, above the clavicle, and deep to the skin.
Normal palpable structures that are NOT pathological masses include the Hyoid Bone, Thyroid cartilage, Cricoid cartilage, the Thyroid Gland (if slightly enlarged), and the Submandibular salivary gland, especially in thin individuals.

Explain the "Rule of 80" for adult non-thyroid neck masses.

The Rule of 80 states that 80% of non-thyroid adult neck masses are Neoplastic, 80% of those neoplastic masses are Malignant, 80% of those malignant masses are Metastatic, and 80% of those metastatic masses originate from a primary source above the clavicle (Head and Neck region).

Explain the "Rule of 7" for the timeline of neck mass presentation, and the 80:20 rule comparing adult versus pediatric masses.

The Rule of 7:
a mass present for 7 Days suggests Inflammatory cause,
7 Months suggests Neoplastic cause, and
7 Years suggests Congenital cause.
The 80:20 rule states that adult neck masses are 80% malignant and 20% benign, while pediatric neck masses are 80% benign and 20% malignant.

Describe how the likelihood of neck mass etiology shifts across pediatric, young adult, and late adult age groups.

In Pediatric patients (0-15 years), Inflammatory/Infectious causes are most likely, followed by Congenital.
In Young Adults (15-40 years), the order is Inflammatory > Congenital > Neoplastic.
In Late Adults (over 40 years), Malignancy is the primary suspicion; any asymptomatic lateral neck mass in an older adult is considered malignant until proven otherwise.

List the differential diagnosis of a midline pediatric neck swelling, and how to differentiate a thyroglossal cyst from a dermoid cyst and from a chondroma.

The differential diagnosis of midline pediatric neck swelling includes Thyroglossal cyst, Dermoid cyst, Chondroma, Pyramidal lobe of the thyroid gland, and Midline lymph nodes.

A thyroglossal cyst is differentiated from a dermoid cyst by movement with tongue protrusion (thyroglossal cyst moves, dermoid does not), and from a chondroma by consistency (chondroma is very hard).

Describe the imaging investigations used for neck masses, including their specific utilities.

Ultrasound is the initial diagnostic tool of choice, cheap and radiation-free, differentiating cystic versus solid masses.
CT scan with contrast shows the mass's relationship to the carotid artery and jugular vein and detects tissue invasion. MRI is best for detailed soft tissue evaluation.

X-ray is generally obsolete for neck masses except for identifying air within a Laryngocele.

Describe the pathological investigation methods for neck masses, including an important safety warning.

Fine Needle Aspiration (FNA) is the preferred initial biopsy method and should be ultrasound-guided for accuracy.
Excisional biopsy is preferred for suspicious lymph nodes to remove the whole node.

Incisional biopsy on metastatic nodes must be avoided because it risks "seeding," the spread of cancer cells along the biopsy track.

Describe the Thyroglossal Cyst, including its location, diagnostic sign, and definitive surgical management.

The Thyroglossal Cyst is the most common congenital neck swelling, located 95% in the midline and 85% above the hyoid bone; it moves upward with tongue protrusion due to its connection to the tongue base.
It can present as a cystic swelling, a solid mass if infected, or a sinus. Mistaking an inflamed cyst for an abscess and performing simple incision and drainage causes a permanent fistula;
correct management is antibiotics for infection first,
followed by the Sistrunk Operation (removal of the cyst, tract, and mid-portion of the hyoid bone) to prevent recurrence.

Describe the Dermoid Cyst and compare the two most common types of Branchial Cleft anomalies.

A Dermoid Cyst is located in the midline and, unlike a thyroglossal cyst, does not move with tongue protrusion.
The 1st branchial cyst is related to the ear (front, behind, or inferior) presenting as a cyst or sinus.
The 2nd branchial cyst is the most common type, located anterior to the SCM in the upper neck, with a tract that can extend up to the tonsils; management requires tracing and removing the cyst, tract, and tonsils together.

Describe the embryological origin of thymic remnants in the neck, and compare Hemangioma with Cystic Hygroma.

The thymus originates from the 3rd branchial arch and migrates down to the mediastinum, so remnants can appear along this path.

Hemangioma is a vascular malformation present at birth or early age with specific skin markers,
while Cystic Hygroma (Lymphangioma) is a lymphatic accumulation with a soft, jelly-like consistency located in the posterior triangle of the neck, treated with injection sclerotherapy.

Describe a Laryngocele, including its types, location, and characteristic aggravating factor.

A Laryngocele is an air-filled cyst of the laryngeal saccule, presenting as external, internal, or mixed types, appearing as a compressible mass located laterally at the level of the hyoid bone.
It increases in size with straining or blowing, making it common in trumpet or wind instrument players, and is visible on X-ray as an air-filled pocket.

Describe Zenker's Diverticulum, including its anatomical basis, demographics, and diagnostic sign.

Zenker's Diverticulum is a mucosal hernia through the pharyngeal wall at Killian's dehiscence (Killian's triangle, between the thyropharyngeus and cricopharyngeus muscles), occurring mainly in elderly patients aged 70-75.

Symptoms include halitosis, regurgitation of undigested food, dysphagia, and choking episodes during sleep from aspiration; diagnosis is via barium swallow showing a pouch behind the esophagus, known as the "apple sign."

List five normal anatomical structures in the neck that can be mistaken for pathological masses, and describe Ludwig's Angina as an inflammatory neck mass.

Normal structures include the hyoid bone, carotid bulb, transverse process of the axis, thyroid gland, and salivary glands.

Ludwig's Angina is a diffuse, severe cellulitis of the submandibular space, 95% originating from dental infections (lower molars), presenting with high-level swelling, hard consistency, and potential airway threat; management is primarily medical with strong antibiotics, with surgery reserved only if ultrasound confirms a focal abscess.

List the benign and primary constitutional malignant tumor types that can present as a neck mass.

Benign tumors include Thyroid Adenoma, Salivary Gland Tumors (commonest being Pleomorphic Adenoma), Neurogenic Tumors (e.g., Schwannoma), Paragangliomas, and Chondroma (cartilaginous, very hard). Primary constitutional malignancies include Lymphoma, Lymphoepithelioma, Lymphosarcoma, Reticulum cell carcinoma, and Leukemia, in addition to Sarcomas, thyroid malignancies, and salivary gland malignancies.

Explain why Nasopharyngeal Carcinoma is called a "hidden" tumor and how it may present.

Nasopharyngeal Carcinoma is often hidden from direct view during standard examination and may present only as a neck mass or as a unilateral ear effusion (fluid behind the eardrum), making it easy to miss without careful nasopharyngeal evaluation.

Differentiate Stridor, Stertor, and Wheezing in terms of sound, timing, and level of airway obstruction.

Stridor is difficult, noisy breathing from partial airway obstruction at or immediately below the larynx.
Stertor is a low-pitched snoring/snuffly sound, always inspiratory, from obstruction at the nasal and/or pharyngeal level.
Wheezing is a whistling sound, mainly expiratory, from lower airway obstruction (e.g., asthma, COPD, or tracheal foreign body).

Explain the relationship between the timing of stridor (inspiratory, biphasic, expiratory) and the level of airway obstruction.

Inspiratory stridor indicates supraglottic and glottic obstruction.
Inspiratory and expiratory (biphasic) stridor indicates subglottic and tracheal obstruction.
Expiratory stridor indicates bronchial obstruction.

Compare the anatomical and physiological features of the infantile larynx versus the adult larynx, and explain why minor edema is far more dangerous in infants (Poiseuille's Law).

The infantile larynx is smaller, positioned higher (C3-C4), has a long/tubular/narrow epiglottis, softer cartilage, loosely attached mucosa, shorter vocal cords, and a premature cough reflex.
Due to Poiseuille's Law (resistance is inversely proportional to radius to the 4th power), a normal 4mm infant airway with just 1mm of edema loses 75% of its cross-sectional area and gains 16x resistance, versus an 8mm adult airway losing only 44% area and 3x resistance with the same 1mm edema.

Describe the three grades of Stridor severity based on retractions, dyspnea, and blood gases.

Grade I (Mild): mild noisy breathing, supraclavicular/suprasternal retractions only, no dyspnea, tachycardia, PO2 greater than 95%, PCO2 less than 35%.
Grade II (Moderate): moderate noisy breathing, adds intercostal retractions, variable dyspnea, rapid pulse, patient irritable/sweating.
Grade III (Severe): severe noisy breathing, adds epigastric retractions, severe dyspnea and cyanosis, rapid irregular pulse, air hunger, PO2 less than 85%, PCO2 35-40%.

Describe Laryngomalacia, including epidemiology, aggravating/relieving factors, and indications for surgery.

Laryngomalacia is abnormal flaccidity of the larynx, the most common congenital laryngeal anomaly and most frequent cause of childhood stridor (60% of infant laryngeal problems), with a boy-to-girl ratio of 2:1.

Inspiratory stridor begins in the first weeks of life, worsens with crying, feeding, supine sleeping, or neck flexion, and improves with neck extension, prone position, or mandible elevation.

Surgical indications (Laser Supraglottoplasty) include severe stridor with failure to thrive, weight loss, chest deformity, cyanotic attacks, cor pulmonale, or hypoxemia/hypercapnia.

Compare Unilateral and Bilateral Congenital Vocal Cord Paralysis in terms of clinical presentation and management.

Unilateral CVC Paralysis (more common on the left, linked to congenital cardiovascular anomalies or iatrogenic surgery) presents with a weak breathy cry and rare choking/cyanotic attacks during feeding; management is observation, as it typically resolves spontaneously.

Bilateral CVC Paralysis (linked to central causes like Arnold-Chiari malformation or birth trauma) presents with severe inspiratory stridor immediately after birth that usually needs tracheotomy, improving with sleep and worsening with activity; management requires surgical airway intervention like tracheotomy, arytenoidectomy, or cordotomy.

Describe Subglottic Stenosis, including its definition, epidemiology, and treatment approach by severity.

Subglottic Stenosis is narrowing of the subglottic lumen to less than 4mm in a full-term newborn (normal is 4.5mm) or less than 3mm in a premature infant; it is the 3rd most common congenital laryngeal anomaly and is considered the most serious.

Severe forms cause stridor and cyanosis immediately after birth, while mild-to-moderate forms cause persistent croup lasting over 3 weeks.

Mild cases are treated conservatively; severe cases require tracheotomy and follow-up, as many children outgrow the problem, plus endoscopic surgical management.

Describe Laryngeal Hemangioma and Laryngeal Web, including key demographics and treatment.

Laryngeal Hemangioma is a congenital vascular malformation in the subglottic region (female to male ratio 2:1), presenting with inspiratory stridor at 6 months of age, treated conservatively via tracheotomy awaiting spontaneous regression (2-4 years), medically with corticosteroids or interferon, or surgically with laser/cryosurgery.

Laryngeal Web is a fibrous band from incomplete recanalization of the laryngeal lumen, most commonly glottic in location, causing abnormal cry with normal feeding; treatment includes bronchoscopic dilation or microlaryngoscopy with keel insertion.

Compare Laryngotracheobronchitis (Croup) and Epiglottitis in terms of etiology, age group, presentation, and radiographic sign.

Croup is viral (parainfluenza, RSV), affecting children 6 months to 3 years, presenting with biphasic stridor, fever, and a painful barking cough, showing a "steeple sign" on X-ray; managed with hospitalization, humidification, and intubation/tracheotomy if needed.

Epiglottitis is bacterial (Haemophilus influenzae type B), affecting children 3-7 years, presenting with fever, dysphagia, stridor, drooling, and a raised-chin open-mouth breathing position, showing a "thumb sign" on X-ray; it is a medical emergency requiring antibiotics and immediate airway securing via intubation or tracheotomy.

Describe the three-step general management approach for airway obstruction/stridor and list the objective blood gas indications for establishing an airway.

The three-step approach is:
1) Conservative medical treatment (semi-sitting position, humidified oxygen, corticosteroids, racemic epinephrine, antibiotics);
2) Establishment of an airway (intubation, cricothyrotomy, or tracheotomy) if conservative measures fail;
3) Management of the underlying cause (e.g., calcium for tetany, extraction for foreign body, drainage for abscess).
Objective indications for airway establishment include hypoxia (PO2 less than 60 mmHg), hypercapnia (PCO2 greater than 50 mmHg), and acidosis (pH less than 7.2).

Differentiate Tracheotomy from Tracheostomy, and list the three primary indications for the procedure.

Tracheotomy is a temporary artificial opening between the trachea and skin, while Tracheostomy is a permanent artificial opening between the trachea and skin.

The three primary indications are: airway obstruction at or above the larynx, ventilation needs (respiratory failure requiring prolonged mechanical ventilation), and airway protection from bronchial secretions or aspiration.

Describe the physiological benefits (functions) of a tracheotomy and classify the procedure by anatomical level.

Functions of tracheotomy include bypassing upper airway obstruction, reducing dead space (70-100 mL) by 10-50%, decreasing airflow resistance, allowing suction access for secretions, providing a pathway for medication/humidification delivery, protecting against aspiration, and allowing swallowing without reflex apnea. By level, procedures are classified as High (1st-2nd tracheal rings), Mid (3rd-4th rings), or Low (5th-6th rings) tracheotomy.

Describe the components and features of a Double Cannula Tracheostomy Tube, and list the features of an ideal tracheostomy tube.

A Double Cannula Tracheostomy Tube has three parts:
the outer cannula (stays in the trachea permanently except for changing), the inner cannula (acts as a safety valve and is removed for cleaning), and the obturator (used for insertion).
The ideal tracheostomy tube features inert material, a double cannula design with a longer inner cannula, a cuff, and fenestration.

List the early and late postoperative complications of tracheostomy.

Early postoperative complications include surgical emphysema, reactionary/secondary bleeding, pneumothorax/pneumomediastinum, tube obstruction or displacement, early tracheoesophageal fistula, infection, recurrent laryngeal nerve paralysis, and aspiration of gastric contents.

Late postoperative complications include difficult decannulation, tracheal granulation, tracheal/laryngeal stenosis, tracheomalacia, delayed hemorrhage after 5 days (from innominate artery erosion), late tracheoesophageal fistula, persistent tracheocutaneous fistula, atelectasis/pulmonary infection, and cosmetic scarring.