Obstructive Signs and Symptoms of Multinodular Nontoxic Goiter
Multinodular nontoxic goiter causes obstructive symptoms primarily through mechanical compression of adjacent structures, with dyspnea, dysphagia, and dysphonia being the cardinal manifestations that warrant surgical evaluation.
Respiratory Obstructive Symptoms
The most clinically significant obstructive manifestations involve the airway:
- Progressive dyspnea is the hallmark respiratory symptom, particularly when the goiter extends retrosternally into the mediastinum causing tracheal compression 1
- Orthopnea (difficulty breathing when lying flat) occurs due to positional changes that worsen tracheal compression 1
- Obstructive sleep apnea can develop from tracheal compression, especially with substernal extension 1
- Stridor represents severe tracheal narrowing and indicates critical airway compromise 1
- Choking sensation is commonly reported by patients with large goiters causing airway pressure 2
The American College of Radiology emphasizes that retrosternal extension into the mediastinum is the primary mechanism causing significant tracheal compression and respiratory distress 1. When respiratory symptoms are present, CT imaging should be performed to evaluate the degree of tracheal compression before considering surgery 3.
Esophageal Obstructive Symptoms
Compression of the esophagus produces:
- Dysphagia (difficulty swallowing) results from posterior goiter extension compressing the esophagus 3, 4, 2
- Patients may describe food "sticking" or require liquids to help swallow solids 2
Laryngeal and Vocal Symptoms
- Dysphonia (voice changes) can occur from mass effect or, less commonly, from recurrent laryngeal nerve compression 1, 3
- Hoarseness may indicate nerve involvement, though this is relatively uncommon in benign goiters 1
- Vocal cord paralysis from recurrent laryngeal nerve injury is rare but represents a serious complication 1
Clinical Context and Severity Assessment
Large goiters (typically >50-80g) are more likely to produce obstructive symptoms 4, 2. The presence of any obstructive symptoms—particularly respiratory compromise—constitutes an indication for surgical treatment 4, 2, 5.
Diagnostic Evaluation for Obstructive Symptoms
When obstructive symptoms are present:
- CT scan is superior to ultrasound for evaluating substernal extension and defining the degree of tracheal compression, with less respiratory motion artifact than MRI 1, 3
- CT better delineates the retropharyngeal space and tracheal narrowing 3
- Chest radiography can help assess compression but CT provides definitive anatomic detail 4
Important Clinical Pitfall
Recurrent laryngeal nerve palsy can cause some respiratory symptoms through vocal cord dysfunction, but it is less commonly the primary cause of significant respiratory distress compared to direct mechanical tracheal compression 1. Don't attribute severe dyspnea solely to nerve injury without imaging the airway.
Treatment Implications
Patients with compression symptoms attributed to the goiter require definitive treatment, with surgery being the preferred approach for nontoxic multinodular goiter causing obstructive symptoms 4, 2, 5. All patients with obstructive symptoms who underwent radioactive iodine treatment in one series showed improvement, though surgery remains the established first-line therapy 6.