A raised hemidiaphragm found on a chest X-ray or CT scan may be the cause of breathlessness — even when you have been told it is incidental. Phrenic nerve paralysis and diaphragm elevation are underdiagnosed causes of unexplained breathlessness, particularly when the breathlessness worsens specifically on bending over, on swimming, or on lying flat. The same page also covers diaphragm eventration, delayed presentation of an old traumatic diaphragm rupture, and the congenital diaphragmatic hernias (Morgagni and Bochdalek) that sometimes present in adulthood. Dr Okiror offers specialist assessment and, where appropriate, robotic diaphragm plication or surgical repair at London Bridge Hospital and The Lister Hospital Chelsea, and on the NHS at Guy’s and St Thomas’. Larger congenital and traumatic hernias are repaired jointly with upper gastrointestinal surgical colleagues. Breathlessness page → · All diaphragm conditions →
Last reviewed: May 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382
Is the raised diaphragm symptomatic or incidental? Answered by upright-supine vital capacity, diaphragm ultrasound with sniff test, and the specific pattern of breathlessness — worse on bending over, swimming, and lying flat.
Robotic diaphragm plication for symptomatic phrenic nerve paralysis and unilateral eventration. The majority of Dr Okiror’s plications are robotic. Published series report sustained 19–23% improvements in lung function at long-term follow-up.
Larger Morgagni and Bochdalek hernias, and delayed traumatic diaphragm ruptures, are operated on jointly with upper gastrointestinal surgical colleagues — both privately at London Bridge Hospital and on the NHS at Guy’s and St Thomas’.
A raised diaphragm on a chest X-ray or CT scan is often labelled incidental. Sometimes that is right. But the label is being applied by clinical impression, not by the specific tests that actually distinguish a symptomatic diaphragm from one that is genuinely not the cause.
Three objective findings change the picture. A vital capacity that drops by more than 20% from upright to supine quantifies the diaphragmatic contribution to breathlessness directly. Paradoxical movement of the diaphragm on ultrasound sniff test — where the affected side rises during inspiration instead of moving down — shows the diaphragm is actively making breathing worse, not simply passive. Breathlessness that worsens specifically on bending over, swimming, or lying flat is close to pathognomonic, because these are the positions in which a paralysed diaphragm displaces furthest into the chest and compresses the lung the most. When all three are present, a raised diaphragm is not incidental. It is the cause.
The diaphragm is the main muscle of breathing. During normal inhalation, the diaphragm contracts and moves downwards, expanding the chest and drawing air into the lungs. When the diaphragm is paralysed — because its controlling nerve, the phrenic nerve, is not functioning — this mechanism fails on the affected side.
In phrenic nerve paralysis, the affected hemidiaphragm does not simply sit still. It often moves paradoxically — rising during inspiration as the other side contracts, because the negative pressure generated by the working diaphragm sucks the paralysed side upwards. This paradoxical movement is mechanically inefficient and actively worsens breathlessness. The elevated position of the diaphragm also compresses the lower lobe of the lung on that side, reducing functional lung volume.
The position in which a patient is most breathless is itself diagnostic. Bending over pushes the abdominal contents further up against the paralysed diaphragm, displacing it into the chest. Swimming — particularly breaststroke — combines bending and partial supine position. Lying flat removes gravity’s assistance entirely, and the abdominal contents push the diaphragm upwards unopposed. Many patients end up sleeping propped up on multiple pillows, or sitting in a chair, without recognising why.
Book a Consultation →Breathlessness that worsens specifically on (1) bending over, (2) swimming, and (3) lying flat is close to pathognomonic for diaphragmatic dysfunction. Patients with breathlessness from other causes — airways disease, heart failure, anaemia — do not show this specific positional pattern.
A raised hemidiaphragm on a CT scan is the starting point, not the answer. Three investigations together decide whether the diaphragm is causing breathlessness and whether plication is likely to help.
Standard spirometry is performed in the upright position and repeated lying flat. Patients with a normally functioning diaphragm show only a small change between the two. Patients with significant diaphragmatic dysfunction show a marked drop in vital capacity when supine, because the abdominal contents push the paralysed diaphragm up into the chest.
A drop of more than 20% from upright to supine is a strong indicator that the diaphragm is contributing meaningfully to breathlessness. The bigger the drop, the more likely surgery will help.
Ultrasound directly visualises the diaphragm during quiet breathing and during a sharp sniff. The test identifies three abnormal patterns:
CT chest and neck (or MRI where relevant) is performed to look for a tumour, enlarged lymph node, or other structural cause along the course of the phrenic nerve — from the cervical spine through the mediastinum.
If a compressive or recoverable cause is identified, that is addressed first. Surgery for the diaphragm comes later, after a period to allow nerve recovery if possible.
Best candidates for plication. Three features predict the best results: (1) typical symptoms — breathlessness worse on bending over, swimming, and lying flat; (2) paradoxical diaphragm movement on ultrasound sniff test; (3) a significant difference between upright and supine vital capacity, ideally 20% or more. When all three are present, plication is highly likely to produce meaningful improvement.
The majority of Dr Okiror’s diaphragm plications are performed robotically, using the da Vinci platform. The patient is positioned on their side under general anaesthesia with single-lung ventilation. Three or four 8mm keyhole incisions are made in the side of the chest — no rib-spreading, no large wound.
Under high-definition magnification, the paralysed or eventrated diaphragm is folded down into a lower, more anatomically correct position and held there with a series of non-absorbable sutures placed precisely. The robotic platform makes the intracorporeal suturing — which is the technically demanding part of plication in a narrow chest — substantially more straightforward than with conventional VATS.
The result is mechanical and immediate: paradoxical movement is eliminated, the lung on that side can fully expand, and the mediastinum — the central structure of the chest containing the heart — is no longer deviated by the elevated diaphragm. Most patients experience measurable improvement in breathlessness within weeks of surgery, with continued improvement over months as the respiratory muscles adapt.
Hospital stay is typically two to three days. Return to normal daily activities is usually possible within two to three weeks. Pulmonary function testing at three and six months after surgery documents the improvement in lung volumes that plication achieves.
Three or four 8mm ports, no rib-spreading, high-definition magnification, articulated instruments that make intracorporeal suturing in a narrow space substantially easier than with conventional VATS. VATS plication is the alternative keyhole approach where robotic access is not available.
In the Mayo Clinic long-term follow-up study of 41 patients (Freeman et al, Annals of Thoracic Surgery 2009), mean improvements at 6 months and sustained at 48 months and beyond were: vital capacity 19%, FEV1 23%, functional residual capacity 21%, total lung capacity 19%. Medical Research Council dyspnoea scores improved substantially [3].
The Leiden long-term follow-up series (Versteegh et al, European Journal of Cardio-Thoracic Surgery 2007) reported that the majority of patients return to a more or less normal way of life after plication, with benefits sustained at long-term follow-up regardless of the cause of phrenic nerve dysfunction [4].
In idiopathic phrenic nerve palsy, spontaneous recovery occasionally occurs within two years of onset. For this reason, surgery is generally not offered until at least 12 months from the onset of symptoms when an identifiable cause has not been found. Where a compressive or structural cause is confirmed, waiting is less justified.
Diaphragm eventration is a congenital condition in which a portion of the diaphragm muscle is permanently thin and weak, causing that part of the diaphragm to sit higher than normal. The phrenic nerve is intact — the problem is the diaphragm muscle itself, not its nerve supply.
Eventration is present from birth but may not cause symptoms until adulthood. Many patients are diagnosed in middle age or later, often when a raised diaphragm is noted incidentally on a chest X-ray performed for another reason. Where eventration is symptomatic, the clinical picture is essentially the same as that of phrenic nerve paralysis: breathlessness worse on bending over, swimming, and lying flat; a significant drop in vital capacity from upright to supine; and on diaphragm ultrasound, the same patterns of reduced excursion or paradoxical movement on the affected side.
Functionally, eventration behaves like phrenic nerve paralysis, and symptomatic patients benefit from the same operation: robotic diaphragm plication. The Calvinho series of long-term follow-up after plication for eventration confirmed durable improvement in pulmonary function and dyspnoea [5].
Blunt or penetrating thoracoabdominal trauma can tear the diaphragm at the moment of injury. When the tear is small or the patient has multiple other injuries dominating the clinical picture, the diaphragm injury can be missed. Over months or years, abdominal contents — stomach, colon, omentum, occasionally spleen or even liver — gradually herniate up into the chest through the unrepaired defect.
The patient eventually presents with breathlessness, chest pain, recurrent chest infections, or symptoms of intermittent gastrointestinal obstruction — sometimes acutely, with bowel strangulation, which is a surgical emergency. By the time the diagnosis is made, the original injury may be years in the past. Reported intervals between injury and diagnosis range from months to several decades [6,7,8].
In the largest series of delayed-presentation traumatic diaphragm rupture (Lu et al, 40 patients, Peking Union Medical College, 2019), around 80% of ruptures were on the left side (the liver buttresses the right hemidiaphragm and is protective). Almost all patients in that series had a documented history of significant past trauma, most commonly a road traffic accident or fall from height [6].
Diagnosis is made by CT chest and abdomen with multiplanar reconstruction. Recognition matters because chronic traumatic diaphragm rupture is mechanically different from acute rupture: there are dense intrathoracic adhesions where abdominal organs have been sitting against pleura for years, the defect is usually large, and the abdomen may have partially lost its capacity to accommodate the returned viscera (loss of domain). These features make repair technically demanding and frequently require mesh reinforcement [9].
The herniated abdominal organs are reduced back into the abdomen, the diaphragm defect is identified and its margins are mobilised, and the defect is closed primarily where possible or with a mesh patch where it is too large to close without tension. Repair is by keyhole (VATS or laparoscopic) approach where the anatomy and adhesions allow; thoracotomy or laparotomy is used where access dictates. Dr Okiror has operated on a number of patients presenting with delayed traumatic diaphragm rupture — sometimes years after the original injury. Where the defect is large or visceral reduction is complex, the operation is performed jointly with upper gastrointestinal surgical colleagues — both privately at London Bridge Hospital and on the NHS at Guy’s and St Thomas’.
Two specific congenital weaknesses of the diaphragm can present in adulthood as a raised hemidiaphragm with herniated abdominal contents. Both are surgically repairable, and larger defects are operated on jointly with upper gastrointestinal surgical colleagues.
Morgagni hernia · Anterior, retrosternal
Foramen of Morgagni HerniaA congenital weakness in the front of the diaphragm just behind the breastbone, through which abdominal contents — most commonly omental fat, transverse colon, or stomach — can herniate up into the chest. Morgagni hernias account for around 3–5% of all congenital diaphragmatic hernias. The right-sided variant is usual; left-sided defects (sometimes called Larrey hernias) are uncommon because the pericardium tends to cover that area [10].
Most adult Morgagni hernias are discovered incidentally on chest imaging. Symptomatic patients present with breathlessness, retrosternal chest pain, postprandial discomfort, or intermittent gastrointestinal symptoms.
Repair is now almost always laparoscopic, often with mesh reinforcement. Smaller, straightforward defects are repaired by Dr Okiror alone. Larger defects with significant visceral content are operated on jointly with upper gastrointestinal surgical colleagues at both London Bridge Hospital and Guy’s and St Thomas’ [11].
Bochdalek hernia · Posterolateral
Adult Bochdalek HerniaA congenital posterolateral defect of the diaphragm caused by failure of fusion of the diaphragmatic foramina during fetal development. Bochdalek hernias usually present in infancy with severe respiratory distress, but rarely remain silent until adulthood. Around 80% of adult Bochdalek hernias are on the left side, because the right side is protected by the liver [12].
Adult presentation is often incidental, but symptomatic patients describe chronic breathlessness, recurrent chest pain, recurrent chest infections, or intermittent gastrointestinal symptoms. Acute presentation with bowel obstruction or strangulation is a surgical emergency.
Repair is recommended once an adult Bochdalek hernia is identified, even when asymptomatic, because of the risk of acute complications. Smaller defects can be repaired by Dr Okiror alone, by laparoscopic or thoracoscopic approach. Larger defects with significant visceral content and a need for mesh repair are operated on jointly with upper gastrointestinal surgical colleagues at both London Bridge Hospital and Guy’s and St Thomas’ [13].
Joint repair pathway. Larger Morgagni and Bochdalek hernias, and delayed traumatic diaphragm ruptures with significant herniation, are operated on by a joint thoracic and upper gastrointestinal surgical team. The thoracic surgeon manages the diaphragm and chest cavity; the upper-GI surgeon manages the herniated stomach, bowel, and abdominal viscera, and any associated procedures. This joint pathway is offered both privately at London Bridge Hospital and on the NHS at Guy’s and St Thomas’.
Patients with a known raised hemidiaphragm are sometimes told there is nothing to do unless symptoms become severe. That is sometimes correct. It is also sometimes a missed opportunity — particularly when the breathlessness pattern is suggestive and the diaphragm has not been formally tested.
Routine spirometry only measures the upright position. A supine measurement, repeated for comparison, is the objective test that quantifies how much the diaphragm is contributing to breathlessness. A drop of more than 20% from upright to supine is highly suggestive.
Ultrasound is the modern test for diaphragmatic function. It identifies absent movement, reduced excursion, or paradoxical movement directly. If your assessment to date has relied only on a chest X-ray showing a raised diaphragm, the diaphragm itself has not yet been tested.
Patients sometimes do not connect chronic breathlessness to a car accident or fall years earlier. Delayed presentation of traumatic diaphragm rupture is well-described, and the CT findings are distinctive once looked for. If there is any past history of significant chest or abdominal trauma, it is worth raising.
A specialist appointment with Dr Okiror is typically available within 2–3 working days at London Bridge Hospital or The Lister Hospital Chelsea. Bring your CT chest, recent spirometry, and any treatment recommendation already made. Self-referrals welcome.
Robotic diaphragm plication and laparoscopic diaphragmatic hernia repair are performed privately at London Bridge Hospital — the primary private centre — and at The Lister Hospital Chelsea. Both have the surgical, anaesthetic, and post-operative respiratory support appropriate for this work. Newsweek World’s Best Hospitals 2026 ranked London Bridge Hospital tenth in the UK, St Thomas’ first, and Guy’s second.
For larger Morgagni and Bochdalek hernias, and for delayed traumatic diaphragm ruptures with significant herniation requiring complex visceral reduction or mesh repair, surgery is performed as a joint operation with upper gastrointestinal surgical colleagues. This joint pathway is offered both privately at London Bridge Hospital and on the NHS at Guy’s and St Thomas’.
Outpatient consultations are also available at HCA outpatients in Canary Wharf and the City of London. Same-day or next-day virtual consultations can be arranged where the case is urgent or the patient is travelling from a distance.
Insurance and self-pay: Dr Okiror is recognised by all major UK private medical insurers including AXA, BUPA, WPA, Vitality, Cigna, and Aviva. Diaphragm surgery involves inpatient care for several days — transparent estimates covering surgical, hospital, anaesthetic, and any joint-team costs are provided by Jo Mitchelson before any commitment is made — 020 7952 2882 or pa@lungsurgeon.co.uk.
Common questions from patients referred with a raised hemidiaphragm, phrenic nerve palsy, eventration, delayed traumatic diaphragm rupture, and Morgagni or Bochdalek hernia. See also the breathlessness page → and diaphragm conditions overview →
Book a Consultation →Or call Jo Mitchelson:
020 7952 2882
Appointments within 2–3 working days. Self-referrals welcome. Surgery at London Bridge Hospital and The Lister Hospital Chelsea, and on the NHS at Guy’s and St Thomas’.
Jo Mitchelson, Designated Medical PA · 020 7952 2882 · pa@lungsurgeon.co.uk
St Thomas’ Hospital #1 UK · Guy’s Hospital #2 UK · London Bridge Hospital #10 UK · Newsweek World’s Best Hospitals 2026
All diaphragm conditions — including hernia, paralysis, and diaphragmatic endometriosis
Unexplained BreathlessnessA raised diaphragm is one of the treatable causes of unexplained breathlessness
Lung Function TestingUpright and supine vital capacity is the test that quantifies diaphragm contribution to breathlessness
EmphysemaPre-existing COPD or emphysema makes diaphragm plication particularly valuable
Pleural Surgery ReferenceThe clinician technical reference page covering the wider pleural and diaphragmatic anatomy
Specialist Second OpinionIndependent review when you have been told a raised diaphragm is incidental but symptoms suggest otherwise