Seiichi Hirobe

Radionuclide imaging study of long-term pulmonary function after lobectomy in children with congenital cystic lung disease.

PURPOSE We evaluated the long-term pulmonary function after lobectomy for congenital cystic lung disease, in both infants and children, using radionuclide imaging (RI). METHODS We performed a retrospective review of 93 patients who underwent resection of cystic lung lesions between 1974 and 2001. The results of postoperative lung volume/perfusion scintigraphy at 1 (n = 64), 5 (n = 32), and 10 years (n = 18) after surgery (V1, 5, 10/Q1, 5, 10) and mean transit time (MTT-a marker for air-trapping) at 1, 5, and 10 years after surgery (MTT1, 5, 10) were compared with respect to age at operation, preoperative infection, underlying disease, and type of surgery. RESULTS Patients who were younger than 1 year at the time of surgery showed a significantly lower MTT5 (1.09 +/- 0.08) and MTT10 (1.15 +/- 0.11) than patients who were older than 1 year at the time of surgery (MTT5, 1.49 +/- 0.67; MTT10, 1.54 +/- 0.33). The noninfected group had significantly higher Q10 and lower MTT10 values (P < .05) compared to the infected group. No significant differences were observed between patients with single lobe vs multiple lobe resection. CONCLUSIONS The optimal age for surgery in patients with congenital cystic lung disease appears to be less than 1 year.

Surgical management of congenital tracheal stenosis

Congenital tracheal stenosis (CTS) is a rare but life-threatening disorder, particularly in neonates and infants. The stenotic lesions are commonly composed of complete rings of cartilage varying in length, location, and severity. A definitive diagnosis of CTS may be delayed because of the rarity of this disorder and thus its unfamiliarity among physicians, its variable onset time, its various clinical symptoms, and the diversity of associated clinical conditions due to the cardiovascular disorders that may accompany it. More than half of the patients who manifest clinical symptoms during early infancy show a long-segment stenosis. Long-segment CTS is problematic and challenging to manage. Over the last two decades several surgical techniques for long-segment CTS have been devised and developed, but no definitively advantageous surgical procedure has been established because of insufficient experience and the lack of large-scale studies. Although rib cartilage tracheoplasty and pericardial patch tracheoplasty have provided limited early to midterm success for infants with long-segment CTS, these procedures are associated with early and late complications, including granulation tissue formation, patch collapse, and restenosis necessitating reintervention. By contrast, slide tracheoplasty has given rise to better surgical outcomes. This procedure enables reconstruction of the stenotic trachea using native tracheal walls with preserved blood supply. The trachea is foreshortened by only one-half of the original stenosis, resulting in reduced tension on the anastomosis. Consequently, the technique has several advantages, including less formation of granulation tissue, satisfactory subsequent growth, and infrequent reoperation for restenosis. Slide tracheoplasty is currently recognized as the preferred technique for long-segment CTS.

Aortopexy for Tracheomalacia With Dextrocardia, Pulmonary Artery Sling, and Congenital Tracheal Stenosis

We report a rare case of coexisting pulmonary artery sling, congenital tracheal stenosis, and dextrocardia caused by right lung hypoplasia. Successful treatment of severe postoperative tracheomalacia was achieved by aortopexy, aiming displacement of the aortic arch across orthogonally in front of the trachea due to dextrocardia. The aim of this surgery was different from the usual aortopexy for tracheomalacia, which lifts the tracheal wall with the aorta. The three-dimensional evaluation considering the patients associated malformations led to a successful result.

Proton Beam Therapy for Inoperable Recurrence of Bronchial High-grade Mucoepidermoid Carcinoma

We report the case of a 17-year-old patient who received four courses of proton beam therapy for inoperable recurrent high-grade bronchial mucoepidermoid carcinoma of the chest wall and lymph nodes. The equivalent doses in conventional fractionation of 79.2-80.6 Gy were applied to the tumor from the first to third courses of proton beam therapy; the hemi-chest wall was also irradiated prophylactically in the third course. The irradiated tumor recurred marginally and liver metastasis developed, but tumor size within the irradiated field was suppressed. Proton beam therapy was also applied to the marginally recurrent tumor in the fourth course. The patient died of cancer about 5 years after the first course of proton beam therapy-about 9 years after the initial diagnosis and surgery. Repeated irradiation of the mediastinum and chest wall with photon radiotherapy is often limited by side-effects in the heart, esophagus and spinal cord. However, no severe late complications in critical organs were detected in this case. Only a Grade 2 skin reaction and lymphatic edema were observed. Therefore, high-dose proton beam therapy may be an option as a salvage therapy with less toxicity to normal tissues compared with photon radiotherapy and provide an alternative to repeated surgery.

Modified slide tracheoplasty for congenital tracheal stenosis

Slide tracheoplasty has become a standard procedure to treat long-segment congenital tracheal stenosis because it is a reasonable and simple technique. Slide tracheoplasty does not affect the carina during long-segment congenital tracheal stenosis management, and thus lesions of the carina, such as stenosis and tracheobronchomalacia can become important causes of extubation failure after surgery. In this manusript, we describe the effectiveness of our modified slide tracheoplasty, which includes reconstruction of the carina. We have performed this technique on three patients, all of whom were extubated without developing any respiratory symptoms.

Laryngeal release with slide tracheoplasty for long-segment congenital tracheal stenosis

Slide tracheoplasty is a standard treatment for long-segment congenital tracheal stenosis (LCTS). However, in severe cases of LCTS, aggressive divisions of inferior constrictor muscle from the thyroid cartilage and extensive circumferential dissection of the upper tracheal segment are often necessary to mobilize the upper tracheal segment enough to make an anastomosis, but they increase the risks of anastomotic dehiscence, recurrent nerve injury, and impaired deglutition. Alternatively, laryngeal release provides safe mobilization of the upper tracheal segment, minimizing dissection of the inferior constrictor muscle and preserving the lateral tissue pedicle without circumferential dissection. We successfully performed laryngeal release with slide tracheoplasty on six patients with severe LCTS, and report our findings.

Bilateral Intralobar Sequestration of the Lung with a Bridging Isthmus: Pathologic and Radiologic Findings

A 4-year-old boy presented with pneumonia. Computed tomography demonstrated a multicystic mass at the posteromedial bilateral lower lobe segments, which were connected by a bronchus behind the heart. Enhanced computed tomography revealed that an anomalous artery arose from the left gastric artery and inserted into the left sequestrated lung and branched to the right one. The diagnosis of bilateral intralobar sequestration (ILS) with a bridging isthmus was made. After removal of the bilateral ILS, radiologic and pathologic approaches were undertaken to reconstruct the vascular and bronchial architectures. The following observations were made: (1) histologically, the region near the anomalous artery insertion site contained bronchial structures, which looked like an ectopic pulmonary hilus. This bronchial structure was continuously observed in the isthmus and its opening of the right sequestrated lung; (2) radiologically, the shape and course of the bronchi within the ILS indicated a distinct bronchial origin that arose from the pulmonary hilus-like structure, and the anomalous artery that ran along with those bronchi, resembled a pulmonary artery. These features suggested that this bilateral ILS might have originated from an accessory lung tissue.

Radiological findings of perivascular epithelioid cell tumour (PEComa) of the falciform ligament.

Perivascular epithelioid cell tumour (PEComa) encompasses a group of mesenchymal tumours composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. A subset of PEComa that typically arises from the falciform ligament and/or ligamentum teres is termed clear cell myomelanocytic tumour of the falciform ligament/ligamentum teres. To date, its imaging findings have not been described. Here, we report the first radiological description of a pathologically confirmed tumour. The patient was a 5‐year‐old girl with a palpable abdominal mass. US, CT, MR and FDG‐PET revealed a midline, well‐defined, solid anterior abdominal wall tumour below the rectus abdominis and contiguous with the umbilicus that was hypervascular and FDG avid. Awareness of these imaging findings facilitates the diagnosis of this distinctive tumour.

Accumulation of gallium-67 within mature and immature teratoma in pediatric patients: investigation for the uptake mechanism.

ObjectiveWe encountered cases of mature and immature teratoma with positive uptake of 67Ga. The objective of this study is to investigate the mechanism of 67Ga accumulation within mature and immature teratomas by comparing the findings of gallium scan, computed tomography (CT), and autoradiography of surgical specimens with the pathological findings.MethodsThe subjects comprised 14 children who underwent surgical resection for intra-abdominal mature and immature teratomas, which were histologically proved to be of the mature and immature subtype. Their age ranged from 24 days to 14 years. The origins of the mature teratomas consisted of seven ovaries including one bilateral case, two retroperitoneal, and two sacrococcygeal regions. The origins of the immature teratomas were retroperitoneum in two cases, an ovary and a sacrococcygeal region. Complete surgical excision was feasible in all children. They underwent both gallium scan and CT prior to surgery. Single-photon emission computed tomography was added in some cases. For two gallium-positive cases, radiography and scintigraphy (autoradiography) of the resected specimen were performed.ResultsOf the 14 children, 5 (one with immature and four with mature subtype) showed positive 67Ga uptake within tumors, which originated from the retroperitoneum in the 3 boys, and from the ovary in the 2 girls. All had typical CT findings of teratoma, including calcifications, fat components, cystic areas, and solid parts. 67Ga accumulation in the four mature teratomas appeared discretely strong, and was considered to correspond with intralesional calcifications. However, in the remaining one immature teratoma, the gallium distribution was diffuse within the tumor. The comparison between radiography and autoradiography of the resected mature teratomas confirmed the correlation between the intralesional calcifications and areas of 67Ga accumulation.ConclusionsA high-uptake ratio of 67Ga in benign teratoma was indicated. A close correlation between gallium scan and CT helps to ascertain whether 67Ga uptake results from malignant and/or immature elements, or mature tissue components.