Antenatal ultrasounds are becoming increasingly good at picking up abnormalities before the child is born. One of the abnormalities that can be picked up in this way are lung abnormalities. The outcomes for children diagnosed with these conditions are usually very good. When a lung abnormality or antenatal cystic lung lesion is identified during your pregnancy there is wide spectrum of possible lesions that may be underlying this finding. The more common lesions include:
- Congenital Pulmonary Airway malformation (CPAM) also known as a Congenital Cystic Adenomatoid Malformation (CCAM)
- Bronchogenic cyst
- Bronchopulmonary Sequestration (BPS)
- Duplication Cyst
- Congenital Lobar/ Segmental Emphysema
Congenital Pulmonary Airway malformation (CPAM)
This is the most common cause of cystic lung abnormality in children. The true incidence is not known but is thought to range between 1:4000- 1:8000 births. These may present antenatally (during your pregnancy) on routine ultrasound screening, following birth or at any time during childhood.
The range of presentations may be related to the size of the CPAM or complications arising in the CPAM. Most often however children will have very few symptoms or even none. Complications that may arise in the CPAM are secondary to compression of normal lung or heart by the lesion, infection (thought to be 5-10%), and rupture of the lesion causing a pneumothorax (leakage of air around the lung). Most of these complications are uncommon. There has been a reported association between CPAM and malignancy in later life. This link however is tenuous and unproven. Treatment depends on the size, and consistency of the CPAM as well as the likelihood for complications.
These lesions are uncommon. A bronchogenic cyst is a fluid filled cyst usually made up of abnormally sited respiratory tissue. These lesions usually occur near the major airways leading to the lungs, but may occur more peripherally in the lung. They carry risk in that they can become infected, and tend to enlarge over time possibly causing compression of the major airways going into the lung. Recommended treatment is surgical excision, which we usually perform using thoracoscopic (Keyhole) surgery.
Bronchopulmonary Sequestration (BPS)
A Bronchopulmonary Sequestration (BPS) is an abnormally developed piece of lung tissue that obtains its blood supply from the systemic rather than pulmonary blood flow. The lesion may be attached or separate from the lung. A BPS may also contain elements of a CPAM (hybrid lesion). The management of this lesion would depend on its size and the size of the abnormal blood supply feeding it. They are often managed in a similar way to a CPAM
This represents a cyst that arises from an attempt to replicate part of the intestinal tract- in the chest this is usually the oesophagus. It is usually attached to the oesophagus and can cause symptoms by obstructing the oesophagus, becoming infected or bleeding. As such we recommend removal, which we usually perform, using thoracoscopic (Keyhole) surgery.
Congenital Lobar/ Segmental Emphysema
This represents a part of the lung with abnormally dilated airspaces, which may in some instances cause compression of the adjacent normal lung. These lesions may be asymptomatic at birth but as they enlarge become symptomatic in the first few weeks to months. Only lesions that produce symptoms require surgery.
When a lung lesion has been diagnosed we would recommend consultation with a paediatric surgeon experienced in the management of paediatric thoracic surgery. We are able to look at the scans and highlight the diagnostic possibilities. We explain the natural history through the pregnancy and provide a plan of management once your baby is born.
Post natal Management
Once babies with a lung lesion are born they are observed to ensure they do not have breathing difficulties and furthermore are able to feed well. We recommend a chest Xray and review by one of our team at birth. If your child is well they can then be discharged with follow up at 1 month to ensure thy continue to thrive and have not developed symptoms over time. Thereafter we recommend a consultation at 3 months if they remain well. We would then recommend a CT scan to provide detail on the size and location of the lesion. The CT scan will need to be performed under a general anaesthetic and this is best performed at a children’s hospital. The next consultation will review the CT scan and detail the size, morphology, and likelihood of developing problems. This will permit us to make a recommendation on either long term follow up or surgical intervention. This plan is developed in consultation with the parents, ensuring they understand the benefits and risks with each approach.
Removal of a lung lesion is undertaken on lesions that cause symptoms, or are likely to cause problems with development of the normal lung or complications later in life. Almost all of our procedures are undertaken via thoracoscopic (keyhole surgery). Our success in completing the procedure thoracoscopically ranges from 70%-95% depending on the site of the lesion and whether there have been preceding complications. If we are unable to complete this thoracoscopically we then perform this through a small curved incision around the shoulder blade working between the muscles so as to minimise post-operative pain. The duration of stay ranges from 2-7 days depending on the approach required. Usually a small chest tube is left post operatively for 1-2 days.