Intratumoral necrosis of lung carcinoma: a potential diagnostic pitfall in incremental dynamic computed tomography analysis of solitary pulmonary nodules?

The authors determined the pattern and enhancement range of necrotic lung carcinoma using incremental dynamic computed tomography (CT). Thirty-seven pathologically proven lung cancers (range, 8-57 mm in diameter) were evaluated using incremental dynamic CT. Scans were obtained before and 30 seconds, 2 minutes, and 5 minutes after the onset of contrast material injection. Computed tomography numbers in circular regions of interest (60% of tumor diameter) were calculated, and the difference in CT number between nonenhanced and the scan showing maximum attenuation was determined. In cavitary necrotic carcinomas, regions of interest were established excluding areas of cavitation. Nine (24%) of 37 lung carcinomas had intratumoral necrosis; four (11%) had noncavitary necrosis, and five (14%) had cavitary necrosis. Maximum attenuation of four noncavitary necrotic carcinomas (mean 31 +/- standard deviation 25 HU; range, -3-56 HU) was lower than cavitary necrotic carcinomas (42 +/- 8 HU; range, 35-51 HU; p = 0.36) and non-necrotic carcinomas (48 +/- 17 HU; range, 25-91 HU; p = 0.07). All carcinomas showed maximum attenuation > or = 25 HU except for one noncavitary necrotic carcinoma (maximum attenuation = -3 HU; 36 mm in diameter). Noncavitary necrosis was recognized as low attenuation on noncontrast scan in two of four cases and as an unenhanced area on enhanced scan in four of four cases. Although noncavitary necrotic lung carcinoma may rarely show maximum attenuation < or = 15 HU, necrotic material is recognized as unenhanced area on enhanced scan.

Small peripheral lung carcinoma evaluated with incremental dynamic CT: radiologic-pathologic correlation.

PURPOSE: To correlate incremental dynamic computed tomographic (CT) and pathologic findings in peripheral lung cancer. MATERIALS AND METHODS: Lung lesions smaller than 3 cm in diameter were evaluated in 18 patients. CT values of the inner area of the nodule at plain CT and at 30 seconds, 2 minutes, and 5 minutes after administration of nonionic contrast material were calculated with incremental dynamic CT. Maximum attenuation was compared with pathologic type of lung carcinoma and with number of vessels and distribution of elastic fibers in the pathologic specimen. RESULTS: Enhancement of all lesions was statistically significant (P < .0001). Maximum attenuation of lung carcinomas correlated positively with number of small vessels (diameter, 0.02-0.10 mm) (r = .77). Distribution of elastic fibers in the tumoral interstitium correlated with maximum attenuation (P = .04 between grades 1 and 3) and with number of small vessels (P = .01 between grades 1-3; P = .008 between grades 1 and 3). CONCLUSION: Enhancement characteristics of lung carcinomas reflect the number of small tumoral vessels and the distribution of elastic fibers in the tumoral interstitium.

Solitary pulmonary nodule: preliminary study of evaluation with incremental dynamic CT.

PURPOSE: To use incremental dynamic computed tomography (CT) to evaluate solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: Thirty-two adult patients with SPNs less than 3 cm in diameter had 18 primary lung cancers, 10 tuberculomas, and four hamartomas. The CT numbers of the inner area of the nodule were calculated before and 30 seconds, 2 minutes, and 5 minutes after administration of contrast material. RESULTS: All lung cancers and one of four hamartomas showed significantly greater enhancement (P < .0001) than benign SPNs, which did not show enhancement (except for one hamartoma). All lung cancers and one of four hamartomas showed complete enhancement, one hamartoma showed peripheral enhancement, two hamartomas and eight of 10 tuberculomas showed capsular enhancement, and two tuberculomas showed no enhancement. CONCLUSION: Maximum attenuation of 20-60 HU appears to be a good predictor of malignancy.

A liquid-liquid blood-gas exchange for the treatment of acute respiratory failure. A new blood gas exchange using artificial blood as an oxygen carrier.

A new liquid-liquid blood gas exchange system was investigated using a venovenous low flow extracorporeal circuit. A 2 m2 hollow fiber dialyzer served as the interface of the blood and oxygen carrier (a 38 percent FC-43, perfluorocarbon emulsion in a buffered electrolyte solution), which was continuously recycled through a bubble oxygenator. Experiments were performed on five mongrel dogs under general anesthesia. Upon the arrest of spontaneous ventilation, the dogs' lungs were inflated with 50% oxygen gas under a positive pressure of 10 cmH2O. After 10 min of apnea the dogs' PaO2 decreased to 37 +/- 14 mmHg, and the extracorporeal circulation was started at 10 ml/min/kg b./w. At 15 min the PaO2 had risen to 80 +/- 41 mmHg and at 30 min to 121 +/- 17 mmHg. The oxygen transfer was 8.3 +/- 2.3 ml/min. The extracorporeal circulation was continued 5h, when PaO2 reached 156 +/- 90 mmHg, and PaCO2 148 +/- 43 mmHg, then stopped. Fifteen minutes later, the PaO2 had returned to 32 +/- 10 mmHg. These findings indicate that our blood gas exchange system can supply a sufficient amount of oxygen to the body under apnea with continuous positive airway pressure.

Superior vena cava syndrome caused by a right apical tense bulla.

Superior vena cava (SVC) syndrome is caused by several diseases, although to our knowledge, a bullous lesion has not been reported previously. In the present case, severe pleural adhesion prevented the expanding bulla from stretching the visceral pleura and from compressing the residual lung, subsequently causing compression of the SVC and thus SVC syndrome.

[A case of pulmonary leiomyosarcoma followed up for five years].

A 70-year-old woman with leiomyosarcoma, followed up for 5 years as tuberculoma, is described. The tumor, in the left lower lobe, had enlarged from 1.5 x 1.5 cm to 3.4 x 3.4 cm in 5 years, and doubling time was calculated to be 540 days. Another tumor (1.8 x 1.8 cm) was also recognized in the right lower lobe at the later time. Since not only a benign tumor but metastatic disease was suspected, thoracotomy was performed, and the intraoperative pathologic diagnosis was leiomyosarcoma. However, only partial lung resection was performed because of the low growth rate of the tumor, the patient's advanced age, limited lymphatic metastasis and favorable prognosis with only partial resection. DNA analysis of the tumor based on flow cytometry showed a diploid pattern, and this was thought to account for the long doubling time of the tumor. The postoperative course was satisfactory without any signs of recurrence at the operation site.

[Clinical study of bioabsorbable PGA sheets for suture reinforcement and use as artificial pleura].

Bioabsorbable PGA non-woven fabric sheets were used to treat 103 patients who underwent pulmonary surgery in three hospitals, and their handleability, applicability, drainage time after surgery and subsequent side effects were studied. For suture reinforcement, these sheets showed satisfactory handleability, applicability and effectiveness for hemostasis and prevention of air leakage at the suture sites. Since this material has good compatibility with fibrin glue, use of these two materials in combination reduced both the operation time and postoperative drainage period. For small fistula and pleural defects, attachment of the sheets with fibrin glue to create an artificial pleura was sufficient for prevention air leakage without suturing. No side effects or complications were observed, and the postoperative courses of all 103 patients were uneventful. These findings suggest that PGA sheets are acceptable for suture reinforcement in the pulmonary surgery, and that when used with fibrin glue, can simplify surgery for emphysematous lung disease and shorten the period of postoperative air leakage.

The effects of cromolyn sodium in dogs undergoing high-frequency oscillation superimposed on conventional mechanical ventilation.

The effects on gas exchange of superimposition of high-frequency oscillation (HFO) (40 Hz) on conventional mechanical ventilation were investigated in mongrel dogs with eucapnic gas exchange on conventional mechanical ventilation (CMV). The dogs were anesthetized, paralyzed, and ventilated with CMV until stable. Oscillation was then superimposed for 15 min, followed by CMV alone for a further 30 min. During HFO superimposed on CMV (CMV-HFO), the arterial carbon dioxide tension (PaCO2) increased from 43.6 +/- 1.2 mm Hg to 47.2 +/- 1.4 mm Hg (p less than 0.02), whereas the arterial oxygen tension (PaO2) did not change at all. The change was inhibited completely by administration of intravenous cromolyn sodium (CS) (6 mg/kg/min). The mean pulmonary arterial pressure (mPAP), cardiac output (CO), pulmonary capillary wedge pressure (PCWP), and pulmonary vascular resistance (PVR) did not change during the experiment. These results demonstrate that CMV-HFO appears to cause CO2 accumulation and eliminates the impaired O2 transfer, and that these effects are inhibited completely by CS administration.

[An adult case of dyspnea and overinflation of the residual lung with disappearance of the postpneumonectomy space after left pneumonectomy].

Mediastinal shift and overinflation of the residual lung after pneumonectomy are well known, and sometimes cause pulmonary insufficiency. However, most of such cases occur after surgery in childhood or adolescence. We present a 49-year-old woman who had dyspnea and severe overinflation of the residual lung after left pneumonectomy. She had undergone pneumonectomy at the age of 33 years. Dyspnea on exertion occurred 4 years later, and became much more severe 9 years later (H-J IV degrees). Computed tomography showed that the postpneumonectomy space and completely disappeared and the right lung was overinflated to the left posterior axillary line. Low vital capacity with high residual volume and low maximal ventilatory volume were detected by pulmonary function test. Pulmonary function after pneumonectomy is difficult to predict because mediastinal shift and overinflation of the residual lung may occur. To avoid this, prosthesis plombage for the postpneumonectomy space is necessary.

[A case of primary pulmonary paraganglioma].

A case of primary paraganglioma of the lung in a 48-year-old woman is presented. She was found to have a coin lesion in lower lobe on routine radiography. Results of bronchoscopic examination were negative, and exploratory right thoracotomy was performed. At operation, non-invasive encapsulated tumor found in posterior basal segment of the right lower lobe was enucleated. Histological analysis of the resected tumor proved to be compatible with pulmonary paraganglioma. Pulmonary paraganglioma is said extreme rare, and so only 21 cases were previously reported in the literature including this case.

[A case of miliary tuberculosis and chest wall cold tuberculous abscess with contents draining into the epidural space].

A 37-year-old man was admitted because of miliary tuberculosis. However, his fever and general condition did not improve with chemotherapy. Six months later, paraplegia occurred following sudden radicular back pain without any alteration of segmental sensation. There were no abnormal findings on X-ray films of the thoracic and lumbar vertebrae. Examination by magnetic resonance imaging revealed that the contents of a cold tuberculous abscess in the right chest wall had drained into the epidural space through the intervertebral foramen. Drainage of the chest wall abscess and laminectomy were performed. Further investigation showed that this case did not belong to the usual type of atypical spinal tuberculosis reported previously.

Palliation of left main bronchus compression due to malignant tumor by intubation via a tracheostomy tube.

Intubation of the left main bronchus via a tracheostomy tube was performed in a patient with local recurrence of lung cancer associated with invasion and obstruction of the left main bronchus after right sleeve pneumonectomy. The result was satisfactory not only for preventing asphyxia, but also for maintaining the patency of the airway after extubation of the endotracheal tube.

Feasibility of intraoperative cytodiagnosis of lung cancer.

Of 354 thoracotomies, 114 cases involved intraoperative cytopathologic evaluation. The study included 86 men and 28 women, and 184 specimens were examined. Smears were taken from the lung lesion or lymph node and the chest wall or bronchial stump by imprint or needle aspiration. Intraoperative evaluations were compared with histologic findings. In 85 cases not diagnosed as malignant preoperatively, malignancy was confirmed in 97.6 percent of cases and histologic type in 71.8 percent. In the 28 cases diagnosed as malignant preoperatively, there was only one false-negative. The most important finding during thoracotomy is whether a lesion is malignant or not. The time required to obtain a pathologic diagnosis also is important. We are able to obtain the results of a cytologic diagnosis within 10 min. Cytologic diagnosis of malignancy during thoractomy may be a feasible and convenient method of diagnosis, especially where malignancy is suspected.

[Effect of erythromycin on the generation of neutrophil chemiluminescence in vitro].

In order to elucidate the therapeutic mechanisms of low dose-long term erythromycin (EM) therapy in patients with diffuse panbronchiolitis (DPB), the authors evaluated the effect of in vitro EM treatment on neutrophil (PMN) oxygen radicals production. EM has potent capacity to suppress PMN chemiluminescence (CL) induced by the N-formyl Met-leu-phe (FMLP), opsonized zymosan, and calcium ionophore A23187 stimulation. In marked contrast, phorbol myristate acetate (PMA)-induced PMN CL were much less affected by EM treatment. The suppressive activity of EM was dependent on the EM concentration and at a EM concentration of 25 micrograms/ml, FMLP-induced PMN CL were suppressed by 45.3 +/- 5.6% (n = 7), but PMA-induced CL were suppressed only marginally, 11.9 +/- 3.7% (n = 7). The onset of inhibitory activity of EM is rapid and at 5 min., 60.1% of the maximum suppression at 60 min. was observed. This EM-induced suppression was found to be reversible and dependent on the EM-pretreatment temperature since the suppressive activity of EM were observed only at 37 degrees C but not at 0 degrees C. These results suggest that actively transported intracellular EM exerts its suppressive activity by inhibiting the process of Ca++ transfer or Ca++ utilization by cells. In addition, these results were consistent with the concept that EM might act as an anti-inflammatory agent in chronic bacterial airway infections such as bronchiectasis and DPB where the PMN appear to play an important role in the generation of airway destruction.

New bioabsorbable pledgets and non-woven fabrics made from polyglycolide (PGA) for pulmonary surgery: clinical experience.

A new type of bioabsorbable pledget made from non-woven fabric of polyglycolide (PGA) fibers has been developed. After the in vivo implantation test using dogs, samples were subject to clinical evaluations in pulmonary operations in four hospitals. The total number of trial cases was 50; in 11 cases pledgets were used for repair of the bronchus and in 39 cases for lung fistulas or defects of the pleurae. Compared with the conventional nonabsorbable pledgets, these PGA pledgets showed satisfactory results. In particular, for cases of emphysematous pulmonary diseases the application of the PGA pledgets and non-woven fabrics made the post-operative air-leakage duration short. In all these 50 cases neither side effect nor complication was observed. This evaluation suggests that PGA pledgets and non-woven fabric are an acceptable and even better alternative to conventional nonabsorbable pledgets for the pulmonary surgery.

A new type of low blood flow ECCO2R using a hemodialysis system in apneic states.

To perform low blood flow extracorporeal CO2 removal (ECCO2R), the authors developed a device for extracorporeal circulation (ECC) equipped with a dialyzer for the elimination of CO2 as bicarbonate. The major problem with this method was the decrease in blood pH. To control blood pH and clarify the limit of CO2 elimination using this method, a study with apneic dogs was performed. Six anesthetized mongrel dogs were intubated and paralyzed with a muscle relaxant. Vascular access was achieved with a venovenous bypass. ECC was initiated under apneic oxygenation (100% O2, 10 cm H2O continuous airway pressure), and the CO2 concentration in the airway outlet was measured. The CO2 was converted to bicarbonate using systemic infusion of trihydroxy-methylamino methane (THAM), and the generated bicarbonate was removed by hemodialysis. Blood flow rate in the ECC was 15 ml/kg/min, and the duration of ECC was 5 hr. During ECC, the hemodynamic parameters of the dogs were stable, and the PaCO2 remained at about 90 mmHg with a PaO2 above 350 mmHg; CO2 elimination from the airway was negligible.

[Pulmonary nodule confirmed by rib consolidation on thoracic computed tomography].

Coin lesions in the thoracic cavity, skin, muscle and connective tissue are clearly observed by computed tomography (CT). However, it is very difficult to detect abnormal shadows in the ribs by thoracic CT at the mediastinal level. We describe 3 cases of pulmonary nodules that were not detected by CT at the mediastinal or lung field level, however, but could be detected at the bone level. When pulmonary nodules cannot be detected by thoracic CT at the mediastinal or lung field level, it is recommended to change the window to the bone level.