What is the initial approach for a 62-year-old man with significant eventration of the left hemidiaphragm?

Initial Approach for Significant Eventration of the Left Hemidiaphragm in a 62-Year-Old Man

Begin with chest radiography (PA and lateral views) as the first-line imaging study to confirm the diagnosis and assess the degree of diaphragmatic elevation, followed by CT chest without IV contrast if surgical intervention is being considered or if the diagnosis remains uncertain. 1

Diagnostic Workup

Initial Imaging Strategy

• Chest radiography is the appropriate first-line imaging modality for evaluating suspected diaphragm dysfunction, as it can assess diaphragm position and provide initial clues to the presence of eventration or paralysis 1
• PA and lateral chest radiographs are preferred over AP portable radiography when feasible, as they provide higher quality images 1
• CT chest without IV contrast serves as the gold standard for confirming diaphragmatic pathology, with sensitivity of 14-82% and specificity of 87% for diaphragmatic abnormalities 1
• CT imaging can accurately determine the presence, location, and size of the diaphragmatic defect and evaluate for complications 1

Functional Assessment

• Fluoroscopic testing can differentiate eventration (no paradoxical motion) from paralysis (paradoxical motion during respiration), which is important for understanding the underlying pathophysiology 2
• Ultrasound findings are concordant with fluoroscopic imaging for diaphragm motion assessment, though it is usually not useful for initial imaging but can serve as a helpful secondary study for dynamic assessment 1
• Fluoroscopy can evaluate diaphragmatic excursion amplitude, thickness, and contraction, with high sensitivity and specificity for diagnosing neuromuscular disorders of the diaphragm 1

Clinical Assessment

Symptom Evaluation

• Assess for respiratory symptoms including dyspnea, tachypnea, recurrent pneumonia, and exercise intolerance, as these are the primary indications for surgical intervention 3, 4
• Evaluate for gastrointestinal symptoms, though these are less common with left-sided eventration compared to right-sided 1
• Document the severity and duration of symptoms, as symptomatic eventration typically requires surgical treatment while asymptomatic cases may be managed conservatively 5, 6, 4

Physical Examination Findings

• Look for decreased breath sounds on the affected left side and dullness to percussion over the lower left hemithorax 3
• Assess for signs of respiratory distress including tachypnea, use of accessory muscles, and decreased oxygen saturation 3

Management Decision Algorithm

Indications for Surgical Intervention

Surgery (diaphragmatic plication) is indicated for symptomatic eventration causing distinct respiratory complaints that can be related to the diaphragmatic pathology and are unresponsive to medical therapy. 5, 6, 2

• All symptomatic patients with elevated diaphragm should undergo plication, regardless of whether the etiology is eventration or paralysis 2
• The goal of plication is to improve lung volumes, decrease paradoxical elevation of the hemidiaphragm, and restore normal pulmonary parenchymal volume by replacing the diaphragm in its normal location 2, 4
• Plication is safe, has excellent outcomes, and is associated with symptom improvement in the vast majority of patients 2

Conservative Management

• Asymptomatic eventration discovered incidentally may be managed conservatively with observation 2, 4
• Medical therapy should be attempted first for mild symptoms, with surgical referral reserved for those who fail conservative management 6

Surgical Approach

Technique Selection

• Most thoracic surgeons perform minimally invasive thoracoscopic plication as the preferred approach 2
• Plication can be approached either from a thoracic or abdominal approach, with thoracotomy being performed in the majority of cases historically 3
• The standard technique involves plication of the diaphragm without incision or excision of the pathologically changed part 5
• In rare cases with very thin diaphragmatic membrane, reinforcement with foreign material may be necessary 5

Expected Outcomes

• Immediate postoperative return of the diaphragm to normal position with clinical improvement occurs in most patients 6, 4
• After plication, there is typically immediate remission of symptoms in most patients, with decreasing symptoms observed over the following year in others 4
• The operated hemidiaphragm becomes immobile without paradoxical motion, and relapse of symptoms is uncommon in patients with properly immobilized diaphragms 4

Important Caveats

Potential Complications

• Be aware that some patients may experience gradual diaphragmatic rise or relapse of respiratory symptoms after repair, particularly in adults 6
• Cardiorespiratory complications can occur in the early postoperative period, though mortality is rare with modern surgical techniques 3

Diagnostic Pitfalls

• Normal chest radiographs can occur in 11-62% of diaphragmatic abnormalities, so maintain clinical suspicion and proceed to CT imaging if symptoms persist despite normal initial radiography 1
• Chest radiography is somewhat limited in its ability to precisely localize abnormalities and differentiate between parenchymal, pleural, and diaphragmatic pathology 1