Masahito Ikeda

Abnormal persistence of the right vitelline vein

The authors describe a case of intestinal obstruction due to a mesodiverticular band, in which both vitelline artery and vein remnants were affirmed to be present histologically. Reviewing case reports in literature, it was revealed that the vein found in the band was the right vitelline vein remnant and that this was an important fact which proved the hypothesis that the superior mesenteric vein derives from the right vitelline vein.

Safe pleural contraction employing a new tip for electrosurgical units. An ex vivo experiment.

BACKGROUND Certain pulmonary lesions are treated by lung tissue contraction induced by heat administered by laser or electrosurgical unit (ES). ESs are comparatively less expensive, less complicated and more ubiquitous than a lasers but with their conventional tip carries the a risk of damaging the pleura. We developed a large ball tip (M-tip) for ES and evaluated its effect on the pleura in comparison with that of Nd:YAG laser in ex vivo lung. METHOD We employed lobes obtained through surgical resection. Using the Nd:YAG laser, the lung was irradiated for 2 seconds at levels of 5, 10 and 20 watts (10, 20 and 40 Joules). Using the M-tip ES, the pleura received treatment at levels of 10, 20 and 40 watts for 2 seconds (20, 40 and 80 Joules) in spray coagulation mode. Upon completion of these procedures, 144 tissue specimens obtained from 24 lobes were examined under light microscopy. RESULTS Upon the application of Nd:YAG at 20 Joules, 22 (92%) of 24 visceral pleura demonstrated amorphous degeneration. With the application of ES at 40 Joules watts, 24 (100%) samples examined demonstrated amorphous degeneration (P = 0.47). Of the samples where pleural destruction was evident (Nd:YAG; 40 Joules, ES; 80 Joules), an accompanying air leak pattern (pleural destruction associated with slight parenchymal contraction) was observed in 5 (21%) of the samples treated with Nd:YAG and in 10 (42%) of those treated with the M-tip ES (p = 0.12). CONCLUSION The M-tip ES induced proper contraction of the pleura with relatively little destructive damage to the pleura at 40 Joules. Accordingly, it may be possible to induce pleural contraction using this new device with the same degree of safely that the Nd:YAG laser provides.

Are superficial bullae with broad bases suitable for ablation

Superficial bullae with broad bases are not suitable for resection, because the residual lung is too deformed to re-expand adequately when we resect them. Therefore, we believe superficial bullae with broad bases are suitable for ablation. It is not clear, however, whether ablated superficial bullae with broad bases remain contracted after treatment or not. We examined the morphologic changes of ablated superficial bullae with broad bases on chest computed tomographs. Ten patients with superficial bullae with broad bases that could be identified on computed tomograph underwent ablation using an electrocoagulator. These bullae were examined by chest computed tomograph preoperatively and again one, three and 12 months after surgery. There were no intra-operative complications. Postoperatively, the only complication was prolonged air leak (more than 7 days) in 1 (10%) patient. Pneumothorax after the operation presented in 1 (10%) patient. Morphologically, a disappearance of air space associated with bulla-wall thickness was observed in 9 (90%) of the 10 heat-ablated lesions and air space decreased in 1 (10%) lesion. Heat ablation proved to be effective in patients with SBBs. Lesions remained contracted for at least one year after the operation.