A raised hemidiaphragm found on a chest X-ray or CT scan may be causing your breathlessness — even if you have been told it is incidental. Phrenic nerve paralysis and diaphragm elevation are underdiagnosed causes of unexplained breathlessness, particularly in patients with pre-existing lung conditions. Dr Okiror offers specialist assessment and, where appropriate, keyhole surgical plication at London Bridge Hospital. Breathlessness page → · All diaphragm conditions →
Last reviewed: April 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382
Raised hemidiaphragm — one side of the diaphragm sits abnormally high. Most commonly caused by phrenic nerve paralysis, but also by eventration, tumour, or previous surgery
Breathlessness — especially on exertion or when lying flat. Often progresses gradually and may be significantly worse than expected in patients with pre-existing lung disease. Many patients are told the finding is incidental when it is in fact symptomatic
Diaphragm plication — keyhole surgical correction of the elevated diaphragm. Performed by VATS or robotic approach at GSTT and London Bridge Hospital. Significant improvement in breathlessness in carefully selected patients
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 just sit still — it may move paradoxically, rising during inspiration as the other side contracts. 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 the functional lung volume available.
Many patients are told the raised diaphragm seen on their X-ray or CT is incidental and does not require treatment. This is sometimes correct — for patients with no significant symptoms and no underlying cause requiring investigation. But for patients with meaningful breathlessness, particularly those with pre-existing lung disease where every unit of lung function matters, a raised hemidiaphragm can be the difference between maintaining an independent lifestyle and severe functional limitation.
Book a Consultation →Assessment includes pulmonary function testing (including measurement of the drop in FVC from upright to supine — a greater than 25% fall suggests significant diaphragm contribution to breathlessness), CT imaging, and in some cases diaphragm fluoroscopy or ultrasound-guided sniff test to confirm paradoxical movement. Where a compressive cause is suspected, MRI or PET-CT of the mediastinum and neck is arranged. Cardiology review is obtained where the history suggests post-cardiac surgery phrenic nerve injury.
Plication is most appropriate for patients with symptomatic breathlessness attributable to unilateral diaphragm paralysis or eventration, where no recoverable underlying cause has been identified or treated, and where the degree of paradoxical movement and lung compression is sufficient to expect functional benefit. Patients with pre-existing COPD, pulmonary fibrosis, or previous lung surgery are often particularly good candidates, as preserving every unit of lung function matters most in this group. All diaphragm conditions →
Diaphragm plication is performed under general anaesthesia. The paralysed or elevated hemidiaphragm is approached through the chest using a keyhole (VATS or robotic) technique — three or four small incisions, each less than 1cm, on the side of the chest. The diaphragm is visualised directly and a series of non-absorbable sutures are placed to fold the diaphragm down to a lower, more anatomically correct position and hold it there.
The result is immediate and mechanical: the 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 as the respiratory muscles adapt to the new mechanics.
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.
VATS or robotic plication through 3–4 small incisions. No rib-spreading, significantly less postoperative pain than open surgery, faster recovery, and shorter hospital stay than traditional thoracotomy.
Published series report improvements in FVC of 15–25% following plication, with corresponding improvements in exercise tolerance and symptom burden. The benefit is greatest in patients with significant paradoxical movement and in those with pre-existing lung disease where baseline function is most compromised.
In idiopathic phrenic nerve palsy, spontaneous recovery sometimes occurs within two years of onset. For this reason, surgery is generally not offered until at least 12 months after the onset of symptoms when an identifiable cause has not been found. Where a compressive or structural cause is confirmed, waiting is less justified.
Common questions from patients referred with a raised hemidiaphragm or phrenic nerve palsy. See also the breathlessness page → and diaphragm surgery page →
Book a Consultation →Or call Jo Mitchelson:
020 7952 2882
Appointments within 2–3 days. Self-referrals welcome. Surgery at London Bridge Hospital and Lister Hospital Chelsea.
Jo Mitchelson, Private PA · 020 7952 2882 · pa@lungsurgeon.co.uk
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