[Comparison of the images in virtual bronchoscopy under different conditions]

OBJECTIVE

We report herein the comparison of the virtual bronchoscopy (VB) images which were constructed with 2 different computed tomography (CT) scanners combined with 3 different applications in 2 healthy adult volunteers.

METHODS

CT scanners were multi-detector row CT (MDCT) [64 detectors] and MDCT (16 detectors). Applications, by which VB images were made, were Leonardo (Leo), Ziostation (Zio), and Plus XNVZ2 (Plus). The image quality was evaluated by 3 expert bronchoscopists.

RESULTS

The change of the threshold value was necessary in Leo for practical use in subsegmental bronchi and more distal area, but unnecessary in Plus or Zio. When Plus was used, the VB images from the data obtained with MDCT (16 detectors) and MDCT (64 detectors) had almost equal quality.

CONCLUSIONS

Although the process to construct VB images was different in each application, it was regarded that Plus was not inferior to Zio or Leo in VB image quality.

Mechanisms of perianeurysmal edema following endovascular embolization of aneurysms

SUMMARY

After coil embolization for an aneurysm, edema surrounding the aneurysm revealed by magnetic resonance imaging (MRI) is rarely seen and is usually associated with neurological symptoms. Perianeurysmal edema was found by postoperative MRI in three out of 182 patients with cerebral aneurysm, which was treated with Guglielmi Detachable Coil (GDC), and neurological symptoms developed simultaneously. In cases where neurological symptoms improved with conservative medical treatment, a temporary increase in the volume of an aneurysm, due to coil and thrombus formation, may result in edema. In cases where symptoms were not alleviated with conservative medical treatment, persistent water-hammer effect against the residual lumen of the aneurysm as well as an increase in the volume of aneurysm by hemorrhage in the aneurysmal wall may contribute to the development of perianeurysmal edema. Consideration of the mechanism of edema development by neurological symptoms, MRI findings, and angiographic findings is needed in order to select appropriate treatment.

Direct superficial temporal vein approach for dural carotid cavernous fistula

SUMMARY

We present an alternative endovascular approach to treat dural carotid cavernous fistulae (dural CCF) that drain only into the superior ophthalmic vein. Four cases of cavernous dural AVFs that could not be treated via the inferior petrosal vein were accessed via the direct superficial temporal vein approach through the superior ophthalmic vein. Successful embolization was documented radiographically and clinically in all patients. The trans-superficial temporal vein approach is safe and useful for inaccessible dural CCFs through the inferior petrosal sinus.

Direct carotid puncture for the endovascular treatment of anterior circulation aneurysms

We report the usefulness of Guglielmi detachable coil (GDC) embolization by direct carotid puncture for anterior circulation aneurysms. For all 27 patients, GDC embolization by direct carotid puncture was safely performed by using a 5F sheath introducer 5 cm long and a Tracker-38 catheter. Neurologic deficits and hemorrhage were not found in any patient during the follow-up period. If the transfemoral approach cannot be applied, GDC embolization should be considered as an alternative method.

The significance of incomplete stent apposition in patients undergoing stenting of internal carotid artery stenosis

BACKGROUND AND PURPOSE

Incomplete stent apposition after carotid angioplasty and stent placement (CAS) is often seen but little is known about how the incomplete attachment goes after stent placement. For example, some may change into restenosis around the stent edge and some may remain unchanged. The purpose of this study is to clarify the morphologic prognosis of an incomplete stent apposition at the stent edge.

METHODS

CAS was attempted on 135 consecutive stenotic lesions (124 patients). Angiograms were then evaluated immediately after the procedure. An incomplete stent apposition at stent edge was found in 15 patients, and all of them were followed up by angiography and MR imaging with antiplatelet therapy.

RESULTS

No ischemic event caused by the lesions occurred during the mean follow-up period of 11 months (from 4 to 32 months). The angiography findings of 15 lesions at a mean of 8.8 months (from 2 to 28 months) after CAS showed that all remained unchanged. No patients required any additional intervention. No new ischemic lesions were detected in any of the 15 patients who underwent follow-up MR imaging at a mean of 10 months (from 2 to 32 months) after CAS.

CONCLUSION

In this study, the existence of a segment of incomplete stent apposition had no adverse morphologic or clinical effect.

[Pulmonary actinomycosis developing diffuse phregmone after pneumonectomy]

The patient was a 75-year-old male who consulted the department of respiratory tract internal medicine in our hospital for left chest pain occurring from the beginning of December 2003. Chest X-ray indicated a tumorous shadow in the left lower lung field. A chest CT also revealed an irregularly shaped mass shadow in the left lower lobe. Since bronchoscopy failed to establish a definitive diagnosis, the patient was referred to our department for surgery to undertake thoracotomy. After left pneumonectomy being performed based on a suspicion of lung abscess, pathological examination of specimen from the resected left lung showed sulfur granules which led to the diagnosis of pulmonary actinomycosis. Because of the diffuse phregmone developing around the surgical wound, benzylpenicillin potassium administration was started, and was continued for a further 6 months on an outpatient basis. Pulmonary actinomycosis is a relatively rare chronic pulmonary infection. It is often difficult to distinguish pulmonary actinomycosis from other pulmonary disease such as lung cancer because of the similarity of their appearance on X-ray or CT, and almost all cases of pulmonary actinomycosis are diagnosed by thoracotomy.

[Large cell carcinoma with chest wall infiltration combined with contralateral giant bulla]

A 48-year-old male consulted the department of respiratory medicine for right precordial pain occurring from the beginning of May 2004. Chest X-ray indicated a tumorous shadow in the right upper lung field and a large left lung cyst. Although chest wall infiltration was suspected based on computed tomography (CT) demonstrating a mass lesion in the right S2, there was no significant swelling of the mediastinal lymph node. On the left side, the lung was markedly compressed by a large cyst in the left upper lobe. Since bronchoscopy failed to establish a definitive diagnosis, the patient was referred to our department for surgery based on a suspicion of malignant pulmonary tumor. Considering both the risk of perioperative complications due to the left cystic lesion at surgery for right lung lesion and the improvement of respiratory function by removing cystic lesion of the left lung, the left side operation was preceded by the right side. Although postoperative examinations of respiratory function did not demonstrate any particular improvement, the results of selective right pulmonary artery obstruction test supported the possibility of pulmonary lobectomy. Therefore, the right upper lobectomy and ND 2a mediastinal dissection combined with chest wall resection was subsequently performed. Postoperative pathological diagnosis revealed that the tumor was a stage IIB large cell carcinoma of pT3N0M0 with costal infiltration.

Spontaneous improvement of persistent ulceration after carotid artery stenting

BACKGROUND AND PURPOSE

Because carotid plaque ulceration is associated with an increased risk of cerebral embolism, residual carotid plaque ulceration directly around a stent (persistent ulceration) after carotid angioplasty and stent placement (CAS) could still be a risk factor for a stroke. The purpose of this study is to understand the morphologic and clinical prognosis of persistent ulceration.

PATIENTS AND TECHNIQUES

CAS was attempted on 91 consecutive stenotic lesions (80 patients). Of these, 54 lesions (48 patients) had ulceration before CAS. Angiograms were evaluated immediately after the procedure. Persistent ulceration was found in 34 lesions (30 patients). The mean depth and length of persistent ulcers were 2.1 mm (range, 1-4.7 mm) and 8.9 mm (range, 1.5-22 mm), respectively. All patients with persistent ulceration were followed with antiplatelet therapy.

RESULTS

No ischemic event due to the lesions occurred during the mean follow-up period of 25.5 months (range, 3-48 months). Angiography on 25 lesions (21 patients) at a mean of 5.8 months (range, 1-21 months) after CAS showed that persistent ulceration disappeared in 12 lesions (48%), improved in 11 lesions (44%), and remained unchanged in 2 lesions (8%). Nine lesions (36%) showed restenosis, which were < or =30% and did not require any additional intervention. New ischemic lesions were not detected in any of the 14 patients (17 lesions) who underwent follow-up MR imaging at a mean of 9 months (range, 1-32 months) after CAS.

CONCLUSION

We conclude that persistent ulceration after CAS improves spontaneously and is not a risk factor for cerebral embolism.

[Abdominal organ infarction encountered immediately after surgery of primary lung cancer]

Very rare cases of abdominal organ infarction after surgery of primary lung cancer were reported. Case 1: Patient 1 was a 70-year-old man who underwent left upper lobectomy and ND 2a in June 1999 based on the clinical diagnosis of stage IA lung cancer. On the 4th postoperative day, the patient developed fever and right flank pain. Abdominal computed tomography (CT) demonstrated a specific finding compatible with renal infarction. The etiology could not be determined. The patient was treated conservatively. However, severe atrophy of right kidney was demonstrated by following CT performed 3 years later. Case 2: Patient 2 was a 70-year-old woman who underwent left upper lobectomy and ND 2a in December 2002 based on the clinical diagnosis of stage IA lung cancer. On the 4th postoperative day, the patient developed abdominal pain in the left upper quadrant, nausea and vomiting which had lasted for 10 days. Abdominal CT demonstrated a wedge-shaped filling defect at spleen compatible with splenic infarction. The etiology could not be determined. The patient was treated conservatively with prophylactic antibiotic therapy and followed closely. Partial atrophy of spleen was demonstrated by following CT performed 4 months later.

[Simultaneous spontaneous pneumomediastinum caused by vocal exercise; report of 2 cases]

Two cases of spontaneous pneumomediastinum caused by vocal exercise were reported. Two 18-year-old men were admitted to our hospital simultaneously in April 2003, because of cervical discomfort and chest pain after vocal exercise of self introduction as a event of freshman in their college. Their chest X-ray film and chest computed tomography (CT) demonstrated typical pneumomediastinum. One of them also showed thoracic epidural emphysema without any particular neurological deficit. Both cases completely recovered by only conservative therapy within 5 days. Spontaneous pneumomediastinum which occurs frequently in young men is thought to be a relatively rare disease showing a good prognosis. It seems important to consider this rare condition when the young man complaints chest pain and discomfort around their neck. We thought that there must be a high possibility of this disease being overlooked as a mere chest pain in young man of unknown reason until now. It is our conclusion that spontaneous pneumomediastinum is a really benign condition that requires no specific examination nor therapy.

[A clinical evaluation of the practical reliability in video-assisted thoracic surgery for right primary lung cancer]

Recently, lobectomy by video-assisted thoracic surgery (VATS lobectomy: VL) has been widely applied to peripheral lung cancer because of its less invasive approach compared to standard thoracotomy (ST). However, the appropriate approach in VL still remains to be solved. The aim of this study was to evaluate the practical reliability of our technical devices in VL for right primary lung cancer. For the VATS procedures, a mini-thoracotomy measuring about 6-7 cm was made in the fourth or fifth intercostal space (ICS) under the auscultatory triangle without rib resection. Two access holes 12 mm in size were also made in the fourth ICS at the anterior axillary line and in the seventh ICS at the posterior axillary line, respectively. These access holes were used for insertion of thoracoscope, endoscopic stapler or retracting instrument according to operative procedure. After stapling of the vessels and bronchus, the resected pulmonary lobe was removed from the thorax using a plastic retrieval bag. The present study showed the technical feasibility of this unique thoracoscopic approach in the standard lobectomy with systematic nodal dissection for right lung cancer.

Clinicopathological Investigation of AVMs Embolized with HEMA-MMA. A New Non-Adhesive Liquid Material

SUMMARY

We have recently developed a non-adhesive liquid embolic agent, hydroxyethylmethacrylate methylmethacrylate copolymer (HEMA-MMA), and used it for arteriovenous malformations (AVMs) in the central nervous system. To evaluate the toxicity and usefulness of this agent, we made a clinicopathological study of AVMs that were embolized with it and then excised surgically. This study includes ten cases: nine with pial AVM and one with scalp AVM. In a pathological study, special attention was paid to vascular and perivascular inflammation, angionecrosis, recanalization of the embolized vessels, and foreign body reactions. Inflammation was absent or very mild regardless of the interval between embolization and excision. There was no angionecrosis. Recanalization could be expected to occur in the partially occluded vessel. Foreign body reactions such as infiltration of monocytes or giant cells, and proliferation of fibroblasts or capillaries were also not seen in any case. It was concluded that HEMA-MMA is an excellent embolic material that is easy to handle, less vasotoxic than other agents, and highly histocompatible.

[Ultrasonographical approach for the diagnosis on the depth of invasion in early bronchogenic squamous cell carcinoma]

It is important to evaluate the depth of invasion to determine the appropriate treatment for roentgenographically occult bronchogenic squamous cell carcinoma (ROSCC). In order to evaluate the actual significance of TUS as a diagnostic tool of intraluminal carcinoma invasion, we have conducted a prospective trial. TUS was performed on 29 lesions of ROSCCs. We ultrasonographically classified the degree of the depth of intraluminal invasion into 2 groups; A: "inside of cartilaginous layer" and B: "cartilaginous layer or over". The patients were treated by irradiation, photodynamic therapy (PDT) or surgical resection. Clinicopathological findings and response to the treatment were compared with this ultrasonographical classification. In the evaluation of invasion within cartilage, the sensitivity was 88.2%, the specificity was 77.8%, the accuracy was 84.6%, and the positive predictive value was 88.2%. With TUS, the decision of treatment modality would be more appropriate.

[Recurrence and pulmonary metastasis of extradural paraganglioma in thoracic vertebral canal: report of a case]

A 70-year-old female was operated on for extradural spinal cord tumor in 1982. Microscopic examination revealed the tumor as paraganglioma. Tumor recurred at paravertebral twice in 1985 and 1989, and they were also resected. In 1995, her chest X-ray film showed round tumor in the right upper field. Exploratory open lung biopsy was performed in 1996, and right upper lobectomy was performed according to for malignant lung tumor because intra-operative microscopic findings showed carcinoid or lung metastasis of paraganglioma. Chest wall tumor at paravertebral was resected at the same time. Postoperative microscopic examination revealed the tumors were same as operated paraganglioma. The 2nd thoracotomy was done in 1999, and two chest wall tumors and a pulmonary nodule in right S8 segment were resected. They were recurrence and pulmonary metastasis of paraganglioma. Now 18 years after initial operation, she is out of hospital in tumor free.

Diagnostic validity of computed tomography for mediastinitis after cardiac surgery

BACKGROUND

Optimal treatment based on appropriate early diagnosis is essential in managing mediastinitis after cardiac surgery. We evaluated the accuracy of thoracic computerised tomography (CT) in the diagnosis of mediastinitis.

METHODS

Forty-one patients in whom we performed CT after cardiac surgery were classified into two groups as follows; Six cases had mediastinitis requiring a redo surgical intervention (Group M). Thirty-five cases recovered without mediastinitis (Group C). Comparisons of CT findings in both groups were made retrospectively.

RESULTS

In group M, CT and re-operations were performed 6.3+/-2.5 days and 8.0+/-5.2 days after previous operation, respectively. All but one of redo surgical procedures were mediastinal lavage and omental transplantation. Two patients died due to septic shock and multiple organ failure. CT in group M showed a soft tissue mass with contrast enhancement in 4 patients, bilateral pleural effusion in 5, free gas appearance in 4, and sternal dehiscence or destruction in 2 patients. Consequently, we regarded 4 of the 6 patients in this group as showing postoperative mediastinitis radiographically. In group C, CT performed 16.6+/-7.1 days after operations revealed findings suggestive of mediastinitis in 6 patients. Therefore, in terms of the validity of CT for the diagnosis of mediastinitis, the sensitivity was 67% and the specificity was 83%.

CONCLUSION

The sensitivity of CT for diagnosis of mediastinitis after cardiac operations is unsatisfactory. Diagnosis by seeking infective changes in a multidisciplinary way is important in dealing with mediastinitis.

Allelic loss on 17p13 (TP53) and allelic loss on 3p21 in early squamous cell carcinoma of the lung

Roentgenographically occult bronchogenic squamous cell carcinomas are early lung cancers that localize in the bronchial wall, and are thought to be a good model to elucidate the carcinogenesis of lung cancer. In the present study, we analyzed the incidence of allelic losses on chromosome regions 3p21 and 17p13 in 40 cases of roentgenographically occult bronchogenic squamous cell carcinomas, using three microsatellite dinucleotide polymorphic markers. We also investigated the relationship between such allelic loss and the clinicopathological findings of those cases. These chromosome regions showed frequent losses. Moreover, the incidence of loss on 17p13 increased gradually along with the advance of the depth of invasion, while the incidence of loss on 3p21 increased along with the advancing length of the longitudinal extension. These results suggested that these chromosome regions play different roles in lung cancer progression, i.e., the 3p21 chromosome region was related to the longitudinal extension of the carcinoma while the 17p13 (p53) region was related to the depth of invasion.

MDM2 expression is associated with progress of disease and WAF1 expression in resected lung cancer

Although MDM2, p21/WAF1, and p53 are considered as regulating each other based on in vitro studies, the relation in human lung cancer is not fully understood. The expressions of these proteins were examined immunohistochemically in 112 resected non-small cell lung cancer specimens and the correlation between them were analyzed. MDM2 was expressed in 45% of all lung cancers. In advanced stage, MDM2-positive cases were observed more frequently than in early stage, showing significant difference. No significant difference was observed in the prognosis of the patients regardless of the expression of any protein. Although no correlation was observed between MDM2 expression and p53 expression, or between p21/WAF1 expression and p53 expression, MDM2 expression was strongly related with p21/WAF1 expression. Therefore, MDM2 expression may relate to the progress of the stage of lung cancer, and MDM2 expression and p21/WAF1 expression may be associated not through the p53-related pathway.

Inhibitory effect of natural and environmental estrogens on thymic hormone production in thymus epithelial cell culture

The present study was carried out to assess the direct effect of natural estrogen and environmental estrogens on thymus epithelial cell (TEC) production/secretion of the thymic hormone thymosin-alpha 1 by using the technique of quantitative high-performance liquid chromatography. The presence of estrogen receptors in the TECs was also investigated. Murine TECs were cultured in the experimental DMEM medium containing various concentrations of natural or environmental estrogens, which was followed by determining the production of thymosin-alpha 1. The production of thymosin-alpha 1 by TECs was significantly inhibited by increasing concentrations of 17beta-estradiol (natural estrogen) over 3 x 10(-11) M, genistein (phytoestrogen) over 3 x 10(-9) M, coumestrol (phytoestrogen) over 3 x 10(-9) M, alpha-zearalanol (livestock anabolic) over 3 x 10(-7) and bisphenol-A (plastic) over 3 x 10(-6) M. Small amounts of estrogen receptor were present in the TECs. The above results clearly indicate that natural and environmental estrogens directly modulate TECs to produce thymic hormone probably through an estrogen receptor mechanism. Furthermore, our finding may be useful for evaluating biological effects of chemicals with estrogenic activity.

The effects of lesions in the nucleus basalis of Meynert and physostigmine on rat frontal cortex acetylcholine level

To clarify the relationship between acetylcholine (ACh) level in the frontal cortex and the area of lesion in the nucleus basalis of Meynert (nbM), we used ibotenic acid to bilaterally lesion the substantia innominata (SI), including the nbM, in rats and measured extracellular ACh by microdialysis. Baseline level of ACh (ACh-baseline) averaged 0.14 +/- 0.07 ng/40 microl/20 min (n=13) in the steady state. We also measured the size of the lesioned areas in the SI (nbM-lesion) by using a computed image analysis system. Both ACh level and nbM-lesion varied widely among animals. The bilateral nbM-lesion averaged 28 +/- 30% (n=13). The correlation coefficient between ACh-baseline and bilateral nbM-lesion was -0.871 (p<0.01). After intraperitoneal injection of physostigmine, maximum ACh levels increased to 0.18 +/- 0.06 ng/40 microl/20 min, and deltaACh (ACh-max/ACh-baseline) averaged 132 +/- 19% (n=8). There was no apparent correlation between deltaACh and bilateral nbM-lesion. These results show that the size of lesioned area in the bilateral SI was strongly correlated with the baseline ACh level in the frontal cortex, and indicate that the nbM is the major functional source of ACh in the frontal cortex. Our results also suggests that physostigmine possibly affects not only spared nbM-originated cholinergic fibers but also non-nbM-originated cholinergic fibers in the rat with the bilateral nbM lesion.

Immunohistochemical study on tumor angiogenic factors in non-small cell lung cancer

BACKGROUND

In order to elucidate the roles of tumor angiogenesis in lung carcinogenesis, the expressions of several angiogenic factors in lung carcinoma tissues were examined.

MATERIALS AND METHODS

Tissue specimens from 112 cases of resected non-small cell lung cancer (NSCLC) were studied. The expressions of platelet-derived endothelial cell growth factor (PD-ECGF) and vascular endothelial growth factor (VEGF) were examined immunohistochemically. Microvessel density (MVD) was also evaluated.

RESULTS

VEGF-positive cases were observed more frequently in advanced stage lung cancers than in early cancers, and VEGF-positive tumors had higher MVD than VEGF-negative tumors, while such differences were not observed for PD-ECGF. In squamous cell carcinoma, the patients with high-MVD tumor had significantly worse survival than those with low-MVD tumor.

CONCLUSIONS

Our results suggest that VEGF plays an important role in angiogenesis of lung cancers, while the contribution of PD-ECGF may be limited.

Leiomyoma of the parapharyngeal space

A rare case of leiomyoma of the prestyloid parapharyngeal space is reported together with computed tomographic and magnetic resonance imaging findings. The tumor appeared as a well-circumscribed ovoid mass with some calcifications and lobulations. Because the attenuation, signal intensity, and shape of the mass were not specific and were similar to those of a pleomorhic adenoma, the most common tumor of the prestyloid parapharyngeal space, radiological differentiation of leiomyoma from pleomorphic adenoma of the prestyloid parapharyngeal space was difficult.

Involvement of the #12u lymph nodes around the upper lobe bronchi in patients with lung cancer of the right middle lobe, right lower lobe, or left lower lobe

In Japan, the lymph nodes around the upper lobe bronchi, known as the #12u nodes, are not included in the nodes recommended for dissection in patients with right middle lobe carcinoma, right lower lobe carcinoma, or left lower lobe carcinoma. However, histologic examination has revealed involvement of these nodes in pneumonectomy patients whose carcinoma originated in the right lower lobe. We histologically examined the lymph nodes from 152 patients with lung cancer to determine the incidence of involvement of the #12u lymph nodes. These nodes were found to be involved in 14 (9.2%) of the 152 patients. The rate of involvement was significantly higher in those with T2-T4 disease than in those with T1 disease, and was also significantly higher in patients with N2 disease than in those with N1 disease. There were two long-term survivors without recurrence, and one other patient who lived for more than 5 years before succumbing to the disease. In conclusion, to ensure removal of all the cancer tissue, it is recommended that the #12u lymph nodes be included in the nodes routinely dissected in patients with right lower lobe carcinoma, right middle lobe carcinoma, or left lower lobe carcinoma.

Expression of Bcl-2, Bax, and p53 proteins in carcinogenesis of squamous cell lung cancer

BACKGROUND

Apoptosis is regulated by many genes, including bcl-2, p53, and bcl-2 family genes. The expression of Bcl-2, p53, and Bax in very early lung cancers or precancer lesions is not been fully understood.

MATERIALS AND METHODS

The expression of these proteins was examined immunohistochemically in 11 normal bronchial epithelia, 23 dysplasias, and 40 roentgenographically occult squamous cell lung cancers (ROCs).

RESULTS

The expression of the Bcl-2 and p53 protein increased along with the advance of the morphological atypia in bronchial epithelial cells, whereas no difference in the Bax expression. The patients with Bcl-2 positive ROCs had a better prognosis than those with Bcl-2 negative ROCs.

CONCLUSIONS

Bcl-2 and p53 proteins play important roles in early steps of carcinogenesis in squamous cell lung cancer of central type. The Bcl-2 protein could be a prognostic marker in ROCs.