gms | German Medical Science

Background: Hybrid lesions (HL) have elements of both congenital pulmonary airway malformation (CPAM) and extrapulmonal sequester (EPS). EPS usually arises in the chest or the abdomen, rarely in the diaphragm. Up to date, the preoperative diagnostic workup based on computed tomography (CT) and ultrasound (US) showed imprecise results. The localization of the lesion could only be ascertained intraoperatively. Open surgical techniques have been most commonly used. We discuss the processes of diagnosis and surgical decision making with special emphasis on the benefits of minimal invasive surgery (MIS).

Materials and methods: We report the case of a 9 month old girl, term born, with an intradiaphragmatic HL. In prenatal US, an eventration of the left diaphragm was suspected. Postnatal the patient was investigated by a plain chest radiograph and US. A mass in the lower lobe interpreted as CPAM type II was detected. CT confirmed this pathology and additionally an aberrant arterial supply was identified. These findings together were suspicious for HL. Due to the risk of infection and cancer later in life, we recommended elective surgery, in spite of the child being asymptomatic. At the age of 5 month, a thoracoscopy was performed showing an eventration of the diaphragm, normal lung and no HL. Therefore, the HL was suspected to be intra-abdominal. Thoracoscopic plication of the eventration was performed. Laparoscopy was postponed in order to avoid the morbidity of a two-cavity approach. An MRI at the age of 9 month showed no changes of the HL itself, but again intrathoracic location was suspected. By laparoscopy the HL could be identified intradiaphragmatically and was removed. The postoperative course was uneventful. The histology confirmed a CPAM type II.

We researched literature in pubmed with the terms “pulmonary sequestration diaphragm”. All articles dealing with the clinical syndrome along with the cited literature were evaluated. 10 case reports were identified and accessible. The following parameters were used for analysis: preoperative diagnosis, diagnostic imaging and surgical approach.

Results: In 5 of the 10 reported cases the EPS was located by a thoracic-abdominal approach, in one of them it was not removed. There was no case employing the strategy of splitting the surgical interventions on two different time points. One case found EPS accidentally during diaphragmatic hernia repair. In most cases MIS was used. 2 EPS were removed by thoracotomy and two by laparotomy. In 4 cases the arterial supply was identified, it came from the celiac axis.

Conclusion: Although CT remains the criterion standard imaging examination in the diagnostic workup of EPS and for planning surgery, the exact localization of such lesions may be discovered only during surgical exploration. MIS is safe and accurate by means of obtaining certainty of anatomical anomalies and treating the malformation. Complications and adverse effects like scoliosis, adhesions, postoperative pain and respiratory impairment can be reduced to a minimum. Conversion to open surgery is always possible, if safe resection by MIS is not possible.

MIS can be used for diagnostic and therapeutic means in case of bronchopulmonary lesions. Especially thoracoscopic surgery has distinctly shown significant benefits over conventional open thoracotomy. If a lesion makes a two-cavitiy approach for resection more likely, the option of a two-step-surgical procedure should be discussed, especially in asymptomatic patients.

Figure 1 [Fig. 1]