Robot-assisted transcervical esophagectomy with a bilateral cervical approach for thoracic esophagectomy

BACKGROUND

Thoracic esophageal cancer resection through the neck approach has recently been reported as mediastinoscopic surgery. We present the first report of a new minimally invasive technique for thoracic esophageal cancer: robot-assisted transcervical esophagectomy with a bilateral cervical approach.

METHODS

Ten cases of robot-assisted bilateral transcervical esophagectomy performed at the National Cancer Center Hospital East, Japan, from February 2023 to August 2023 were reviewed. The short-term surgical outcomes were presented, and the feasibility and efficacy of this procedure were discussed.

RESULTS

The mean operation time for the cervical procedure was 184.2 ± 23.6 min. The total time for the whole procedure was 472.7 ± 28.4 min, and total intraoperative blood loss was 162.2 ± 40.0 ml. Among the 10 cases, one patient developed recurrent nerve paralysis, one patient developed pulmonary complications, and no patients developed postoperative pneumonia. The median postoperative hospital stay was 22 (range: 12-43) days. No patients developed severe postoperative surgical complications, which were graded as Clavien-Dindo ≥ III. The total number of surgically harvested mediastinal lymph nodes was 37.2 ± 11.2.

CONCLUSIONS

Robot-assisted bilateral transcervical esophagectomy, a novel procedure for thoracic esophageal cancer, was safe and feasible. Using this procedure, the incidence of recurrent nerve palsy, which is a problem with transcervical esophagectomy and mediastinoscopic esophagectomy, is expected to decrease.

Examination of Factors Related to Problem Drinking Among the Working Population: The Japanese Civil Servants' Study

Problem drinking affects not only the health of a population but also the productivity of a nation, especially if it is rampant among the working population. This study examines the association between problem drinking and work characteristics, work-family status, and social situation among the Japanese working population. Multivariable logistic regression analysis was performed on the basis of gender on 3136 participants (men: 65.1%, women: 34.9%), adopted from the Japanese Civil Servants Study in 2014 (response rate: 87.8%), to examine the factors related to problem drinking, after adjusting frequency and quantity of drinking. Problem drinking was assessed using the Cutdown, Annoyed, Guilty, and Eye-opener (CAGE) questionnaire. The prevalence of problem drinking was found in 24.3% of men and 10.3% of women. The analysis showed that in men, low work performance (OR: 1.34, 95%CI: 1.00-1.79), high family-to-work conflict (OR: 1.54, 95%CI: 1.14-2.09), and high work-to-family conflict (OR: 1.63, 95%CI: 1.14-2.34), were significantly associated with problem drinking, whereas in women, high work-to-family conflict (OR: 2.45, 95%CI: 1.21-4.95) was significantly associated with problem drinking. Although the number of close friends is negatively associated with problem drinking in women, the significance disappeared in the full adjusted model. It can be concluded that it is important for both men and women to strike a balance between work and family life. Moreover, owing to gender differences, work performance may be important for men, and the presence of close friends for women, in reducing the risk of problem drinking.

A novel imaging technology to assess tissue oxygen saturation and its correlation with indocyanine green in the gastric conduit during thoracic esophagectomy

BACKGROUND

Anastomotic leakage in esophagectomy is a serious complication, and assessing blood perfusion in the conduit can help minimize this risk. Indocyanine green is the most widely used method to assess tissue blood flow; however, this technique has disadvantages. Evaluating tissue oxygen saturation in the gastric conduit during thoracic esophagectomy compared with indocyanine green blood perfusion assessment addresses these disadvantages and can be performed easily and repeatedly.

METHODS

This was a prospective study of patients with esophageal cancer who underwent thoracic esophagectomy. Intraoperative tissue oxygen saturation and indocyanine green measurements were obtained to determine the anastomotic site and to compare the correlation between the 2 methods. Tissue oxygen saturation and indocyanine green values were obtained at the tip of the gastric conduit, the demarcation line indicating visible perfusion, and the end of the right gastroepiploic artery.

RESULTS

Fifty-seven patients were enrolled in this study; 3 developed anastomotic leakage, and all 3 underwent robotic thoracic surgery. The tissue oxygen saturation value decreased gradually toward the tip of the conduit, as did congestion, and was significantly decreased at the tip compared with the value at the demarcation line (P = .001). Mean tissue oxygen saturation differed significantly between the leakage and no-leakage groups at the anastomosis site (P = .04). We found a negative correlation between tissue oxygen saturation and indocyanine green values at the end of the right gastroepiploic artery (r = -0.361; P = .03).

CONCLUSION

Tissue oxygen saturation imaging was useful in determining the anastomotic site and addressed the disadvantages associated with indocyanine green.

A novel device to assess the oxygen saturation and congestion status of the gastric conduit in thoracic esophagectomy

BACKGROUND

In thoracic esophagectomy, anastomotic leakage is one of the most important surgical complications. Indocyanine green (ICG) is the most widely used method to assess tissue blood flow; however, this technique has been pointed out to have disadvantages such as difficulty in evaluating the degree of congestion, lack of objectivity in evaluating the degree of staining, and bias easily caused by ICG injection, camera distance, and other factors. Evaluating tissue oxygen saturation (StO2) overcomes these disadvantages and can be performed easily and repeatedly. It is also possible to measure objective values including the degree of congestion. We evaluate novel imaging technology to assess tissue oxygen saturation (StO2) in the gastric conduit during thoracic esophagectomy.

METHODS

Fifty patients were enrolled, with seven excluded due to intraoperative findings, leaving 43 for analysis. These patients underwent thoracic esophagectomy for esophageal cancer. The device was used intraoperatively to evaluate tissue oxygen saturation (StO2) and total hemoglobin index (T-HbI), which guided the optimal site for gastric tube anastomosis. The efficacies of StO2 and T-HbI in relation to short-term outcomes were analyzed.

RESULTS

StO2, indicating blood supply to the gastric tube, remained stable beyond the right gastroepiploic artery (RGEA) end but significantly decreased distally to the demarcation line (p <  0.05). T-HbI, indicative of congestion, significantly decreased past the RGEA (p <  0.05). Three patients experienced anastomotic leakage. These patients exhibited significantly lower StO2 (p <  0.01) and higher T-HbI (p <  0.01) at both the RGEA end and the demarcation line. Furthermore, the anastomotic site, usually within 3 cm of the RGEA's anorectal side, also showed significantly lower StO2 (p <  0.01) and higher T-HbI (p <  0.01) in patients with anastomotic leakage.

CONCLUSIONS

The novel device provides real-time, objective evaluations of blood flow and congestion in the gastric tube. It proves useful for safer reconstruction during thoracic esophagectomy, particularly by identifying optimal anastomosis sites and predicting potential anastomotic leakage.

The feasibility of post-photodynamic therapy salvage esophagectomy in patients with esophageal squamous cell carcinoma treated with definitive chemoradiotherapy

BACKGROUND

Photodynamic therapy (PDT) is a minimally invasive salvage treatment for local residual or recurrent lesions that persist after the definitive chemoradiotherapy (dCRT) of esophageal cancer. However, esophageal cancer persistence after PDT is associated with a poor prognosis. Although esophagectomy is a curative treatment option, few studies have evaluated its efficacy. Thus, this study aimed to evaluate the outcomes of salvage esophagectomy after PDT.

METHODS

14 patients who underwent salvage esophagectomy for residual or recurrent esophageal cancer after PDT between April 2006 and November 2022 at our institution, were enrolled. The short-term (e.g., blood loss, operative time, R0 rate, postoperative complications, and postoperative hospital stay) and long-term (e.g., overall survival [OS] and recurrence-free survival [RFS]) of salvage esophagectomy after PDT were evaluated retrospectively.

RESULTS

The median operative time and intraoperative blood loss were 355 min and 350 ml, respectively. Eight patients (57.1%) had postoperative complications of Clavien-Dindo grade II or more. The median postoperative hospital stay was 20.5 days. The 3-year OS and RFS rates were 23.5% (95% confidence interval [CI] 5.7-48.0) and 16.3% (95% CI 2.7-40.3), respectively. Seven patients with an R0 had significantly longer OS than the seven patients with R1 and 2 (p = 0.045). The 3-year OS rate for patients with R0 was 52.6%.

CONCLUSIONS

Although salvage esophagectomy after PDT carries certain risks, patients who achieved an R0 had a promising long-term prognosis. The location and size of the lesion may be critical factors in determining whether R0 can be achieved with salvage esophagectomy after PDT.

[Management of Postoperative Infectious Complications After Thoracic Esophagectomy]

Although minimally invasive procedures such as thoracoscopic surgery and robot-assisted surgery have become increasingly popular in esophageal cancer in recent years, perioperative management remains a very important topic. However, perioperative management is still an extremely important issue, as esophagectomy is still a highly invasive procedure. Especially in recent years, as the patient population ages, it is expected that we will have more and more opportunities to deal with patients with various pre-existing medical conditions in addition to the original decline in physical function. In this article, we discuss the management of infectious complications in the perioperative management of esophageal surgery, with a particular focus on esophagectomy and reconstruction.

A comparison of the short-term outcomes between laparoscopic and robotic distal gastrectomy: A retrospective study using a nationwide inpatient database

BACKGROUND

Although the safety of robotic distal gastrectomy has been studied in several single-center trials, the nationwide outcomes of robotic distal gastrectomy that meet the requirements of Japanese national health insurance, such as facility case volume and skill level of the surgeon, are still not clear. The objective of this study was to evaluate the short-term outcomes of robotic distal gastrectomy, which was covered by national health insurance, compared to laparoscopic distal gastrectomy.

METHODS

We retrieved gastric cancer cases with cStage I to III who underwent laparoscopic distal gastrectomy (15,539 patients) and robotic distal gastrectomy (1,312 patients) between April 2018 and March 2020 from the Diagnosis Procedure Combination database. We compared the frequency of postoperative complications, anesthesia time, and postoperative hospitalization days between laparoscopic distal gastrectomy and robotic distal gastrectomy using propensity score matching analysis.

RESULTS

The postoperative complication rate were not different between laparoscopic distal gastrectomy and robotic distal gastrectomy (odds ratio = 0.90, 95% confidence interval: 0.66 to 1.23, P = .52). The anesthesia time (minutes) was significantly longer (coefficient = 70.2, 95% confidence interval: 63.8 to 76.7, P < .001) and postoperative hospitalization (days) was significantly shorter (coefficient = -0.89, 95% confidence interval: -1.48 to -0.31, P = .003) in robotic distal gastrectomy than laparoscopic distal gastrectomy.

CONCLUSIONS

Robotic distal gastrectomy that met strict national health insurance coverage requirements in Japan was performed as safely as laparoscopic distal gastrectomy with reduced hospitalization days.

The impact of lymphadenectomy on lymph node recurrence after performing various treatments for esophageal squamous cell carcinoma

Background

Treatment for regional lymph node recurrence after initial treatment for esophageal squamous cell carcinoma (ESCC) differs among institutions. Though some retrospective cohort studies have shown that lymphadenectomy for cervical lymph node recurrence is safe and leads to long-term survival, the efficacy remains unclear. In this study, we investigated the long-term outcomes of patients who underwent lymphadenectomy for regional recurrence after treatment for ESCC.

Patients and methods

We retrieved 20 cases in which lymphadenectomy was performed for lymph node recurrence after initial treatment for ESCC in our hospital from January 2003 to December 2016. Initial treatments included esophagectomy, endoscopic resection (ER) and chemoradiotherapy/chemotherapy (CRT/CT). Overall survival (OS) and recurrence-free survival (RFS) after lymphadenectomy were calculated by the Kaplan–Meier method. We also used a univariate analysis with a Cox proportional hazards model to determine factors influencing the long-term outcomes.

Results

The five-year OS and RFS of patients who underwent secondary lymphadenectomy for recurrence after initial treatment were 50.0% and 26.7%, respectively. The five-year overall survival rates of patients who received esophagectomy, ER and CRT/CT as initial treatments, were 40.0%, 75.0% and 50.0%, respectively. The five-year OS rates of patients with Stage I and Stage II-IVB at initial treatments were 83.3% and 33.3%, respectively.

Conclusions

Lymphadenectomy for regional recurrence after initial treatment for ESCC is effective to some degree. Patients with regional recurrence after initial treatment for Stage I ESCC have a good prognosis; thus, lymphadenectomy should be considered for these cases.

[A case of splenic injury after colonoscopy]

An 81-year-old woman lost consciousness and was taken to our hospital 3 days after colonoscopy was performed as a follow-up of endoscopic mucosal resection done 1 year ago for early sigmoid colon cancer detection. She had left hypochondrial pain. Based on abdominal contrast-enhanced computed tomography (CT) findings, she was diagnosed with abdominal bleeding due to injury to the lower splenic pole, and an urgent splenectomy was performed. In this case, there was no abdominal trauma to cause splenic injury. Injury to the lower splenic pole during colonoscopy was considered due to the adhesion found in the abdominal cavity. It is possible that the hemorrhage did not stop because she was taking antiplatelet drugs.

Autoimmune Hepatitis Associated with Immune Thrombocytopenic Purpura

Although autoimmune hepatitis (AIH) is frequently complicated with chronic thyroiditis or other autoimmune disorders, reports on its association with immune thrombocytopenic purpura (ITP) are scarce. We herein describe a case of AIH associated with ITP. A 75-year-old Japanese woman was admitted to our hospital due to increased aminotransferase levels and severe thrombocytopenia. Elevated serum immunoglobulin G (IgG) was detected, and tests for platelet-associated IgG and anti-nuclear antibody were positive. Following the diagnosis of AIH-associated ITP, prednisolone treatment of 0.6 mg/kg/day resulted in a decrease in the aminotransferase levels and an increased platelet count.

Colonic diverticular hemorrhage: the hood method for detecting responsible diverticula and endoscopic band ligation for hemostasis

BACKGROUND AND STUDY AIMS

Although colonic diverticular hemorrhage is a common cause of lower gastrointestinal bleeding, the low rate of detection of the diverticula responsible for bleeding, together with inadequate evaluation of endoscopic hemostasis, remain unsatisfactory.

PATIENTS AND METHODS

Over 3 years, we employed the hood method to diagnose diverticular hemorrhage in 53 patients and applied endoscopic band ligation (EBL) for hemostasis in 27 patients with responsible diverticula.

RESULTS

The hood method revealed active bleeding in 13 patients (24.5%), nonbleeding visible vessels in 14 patients (26.4%), and presumptive diverticular hemorrhage in 26 patients (49.1%). The nonbleeding visible vessels were located in the diverticular dome in 13 patients and at the diverticular orifice in one patient. EBL was performed in 27 patients, and a hemostasis rate of 96.3% was achieved. In 9 of 12 patients treated with EBL, follow-up colonoscopy revealed resolution of the responsible diverticula.

CONCLUSIONS

The hood method improves the detection rate of diverticula responsible for bleeding by revealing potential nonbleeding visible vessels in the diverticular dome. EBL may become an effective procedure for hemostasis of colonic diverticular hemorrhage.

Ileocecal collision tumor composed of adenocarcinoma and primary malignant lymphoma

Collision tumor means that two kinds of histologically distinct tumors coexist and neighbor without histological interminglement. This report describes a rare case of an ileocecal collision tumor composed of adenocarcinoma and primary malignant lymphoma. A 76-year-old woman was referred to our institute with anemia and a right lower quadrant mass. Colonoscopy revealed type 2 advanced colon cancer in the cecum accompanied by a submucosal mound neighboring this cancer, which appeared different from the usual shape of colon cancer. A barium enema study manifested the typical apple-core sign in the cecum with a smooth semicircular line appearing in the shadow of the apple-core sign. Biopsy specimens showed adenocarcinoma, so a right hemicolectomy was performed. The gross resected specimen presented a mass measuring 64 × 58 × 28 mm at the ileocecal portion. The half of this mass on the colonic side had a crater-like appearance, whereas the remaining part of the mass on the ileal side had an aspect with a smooth surface. Microscopic examination disclosed that the mass was composed of adenocarcinoma and malignant lymphoma bordering on each other and mediated by a thin layer of connective tissue. Cases of colon tumors with an unusual epithelial and submucosal appearance may be instances of collision tumors composed of cancer and malignant lymphoma.

[A case of recurrent gastric cancer with obstructive jaundice successfully treated by docetaxel]

Recently, treatment by taxane regimen for advanced gastric cancer as second-line chemotherapy has been increasingly reported. A 58-year-old man underwent distal gastrectomy for advanced gastric cancer on November 25, 2002. There was permeation through the duodenum side, and a Billroth II operation was done for repair. Although a relapse was not clear from the picture image, due to the tumor marker increase since July 2004, chemotherapy using TS-1 100 mg/day was given. On February 2005, liver dysfunction and obstructive jaundice appeared, and the patient was diagnosed with a recurrence in the hilar lymph node of the liver through PET and CT. Because of the Billroth II operation for repair, ERBD was impossible, and we performed PTCD to decrease jaundice. Treatment by docetaxel 60 mg/m(2) every three weeks was given since March 15. After two courses of chemotherapy with docetaxel, the insertion of the guide wire was possible from the part of PTCD. Implantation of the stent became possible after four courses. PTCD could be removed, and the patient QOL has effectively improved. Outpatient treatment became possible for him in January 2006.

The clinical significance of colonoscopy in hemorrhagic colitis due to enterohemorrhagic Escherichia coli O157:H7 infection

BACKGROUND AND STUDY AIMS

Although hemorrhagic colitis due to enterohemorrhagic Escherichia coli O157:H7 (O157) infection has recently attracted increasing attention as an important enteric infection, the colonoscopic findings associated with this disease have not been sufficiently characterized. The aim of this study is to characterize the colonoscopic features of hemorrhagic colitis due to O157 infection.

PATIENTS AND METHODS

The colonoscopic findings in ten patients with hemorrhagic colitis due to O157 infection were retrospectively reviewed. To assess the severity of inflammation in each part of the large intestine, colonoscopic findings were categorized into four grades: grade 1, intact mucosa; grade 2, sporadic erythema and erosion; grade 3, mostly diffuse inflammation; and grade 4, diffuse, severe inflammation.

RESULTS

Eight out of ten patients had grade 4 findings in the cecum and ascending colon, grade 3 in the transverse colon and descending colon, and grade 2 in the sigmoid colon. Two of these eight patients also had grade 4 inflammation in the proximal transverse colon. Five of these eight patients revealed longitudinal ulcer-like lesions in the transverse colon and/or descending colon. The remaining two patients had grade 3 findings in the cecum to the descending colon and grade 2 findings in the sigmoid colon. All patients exhibited grade 1 finding in the terminal ileum and the rectum. Based on these colonoscopic findings, the ten patients were divided into the typical group (eight patients) and the mild-type group (two patients).

CONCLUSIONS

The characteristic colonoscopic findings in most patients with hemorrhagic colitis due to O157 infection were as follows: 1) severe inflammation, including primarily marked edema and facile hemorrhage, and 2) inflammation predominating at the right-side colon; and 3) frequent appearance of longitudinal ulcer-like lesions.

Lipocortin-1 fails to ameliorate ischemic brain edema in the cat

It has been reported that corticosteroids exert their anti-inflammatory action through de novo synthesis of phospholipase-inhibitory proteins called lipocortins (annexins). We postulated that the following may lessen the effectiveness of corticosteroids on acute ischemic brain edema: 1) lipocortins are induced several hours after administration of steroids; 2) de novo synthesis of lipocortins is suppressed in the ischemic brain; and 3) lipocortins induced systemically do not pass through the blood-brain barrier (BBB) to reach the sites of ischemic edema. To test this hypothesis, we examined whether dexamethasone, given long before ischemia or direct administration of recombinant lipocortin-1, combined with or without BBB opening, ameliorate ischemic brain edema. Three hours before occlusion of the middle cerebral artery (MCA) in the cat, 4 mg/kg of dexamethasone was injected intravenously. The animals were subjected to 4 hours of ischemia. Alternatively, 2 ug/ml (total volume 10 ml) of recombinant human lipocortin-1 (annexin-I) was perfused intermittently into the ischemic focus by catheterization into the MCA. Artificial opening of the BBB was performed by intra-arterial mannitol infusion. None of these strategies demonstrated amelioration of ischemic edema. We conclude that: Dexamethasone and recombinant lipocortin-1 seem unlikely to have robust effects on amelioration of acute ischemic edema.

Lipocortin-1 fails to ameliorate cold-injury brain edema in the rat

Based on evidence that corticosteroids exert their anti-inflammatory action via de novo synthesis of phospholipase A2 inhibitory proteins called lipocortins, we examined effects of high dose dexamethasone and recombinant human lipocortin-1 (annexin-I) on cold-injury brain edema in the rat. Since it takes several hours for lipocortins to be induced, dexamethasone (10 mg/kg) was injected intraperitoneally 3 hours before cold injury. Recombinant lipocortin-1 was administered intraventricularly at three different doses (0.01 mg/kg, 0.05 mg/kg, or 0.1 mg/kg: total volume 20 microliters), or via the internal carotid artery at a dose of 10(-7) M (2 ml). To induce cold injury, a liquid-nitrogen-cooled probe was placed on the exposed dura of male Wistar rats (330-370 kg) for 1 minute. Specific gravimetry and/or a wet-dry weighing method were used for measurement of brain edema at 24 or 48 hours after lesion production. In the present study, dexamethasone and recombinant lipocortin-1 failed to attenuate edema formation. The anti-inflammatory effects of dexamethasone or exogenous lipocortin-1 seemed unlikely to affect cold-injury brain edema.

Surgery or gamma -knife for the treatment of arteriovenous malformations?

Decision making for either surgery or gamma-knife for the treatment of arteriovenous malformations (AVMs) cannot be uniform. The skill of the neurosurgeon in operating on AVMs is now being compared with that of the gamma-knife. The decision varies from case to case and is to be taken by the neurosurgeon. This report presents three cases in which such decision making was not easy. Case 1 was a non-ruptured cingulate AVM of 2.5 cm diameter in the cingulate cortex. The operative field was anticipated to be very narrow between the parietal bridging veins. Case 2 was a tiny ruptured AVM in the speech-motor area which was buried underneath the cortex. Case 3 was a large ruptured thalamo-stiriate-capsular AVM with feeders from the anterior and posterior choroidal arteries. All cases were operated without serious morbidity. A combination of pre-operative intravascular surgery (cases 1 and 3) or postoperative gamma-knife (case 3) was adopted. In conclusion, there is no unitary rule to decide on surgery or gamma-knife for the treatment of AVMs. It depends on what good or harm the responsible surgeon or the gamma-knife does.

Jugular bulb diverticulum associated with lower cranial nerve palsy and multiple aneurysms

BACKGROUND

Jugular bulb diverticulum is a rare condition that has never been reported in association with lower cranial nerve palsy.

CASE DESCRIPTION

A 54-year-old woman developed acute swallowing disturbance and hoarseness. Neuroradiological examinations demonstrated a jugular bulb diverticulum as well as unruptured internal carotid and basilar tip aneurysms on the same side. Laboratory data for both serum and cerebrospinal fluid were normal. Steroids were given, and the cranial nerve palsy disappeared within 1 month. The aneurysms were successfully clipped. During the follow-up period of more than 1 year, the patient has done well and has no neurological deficit.

CONCLUSION

This is the first reported case of jugular bulb diverticulum associated with a lower cranial nerve palsy and multiple aneurysms. We recommend close observation of patients with this condition regardless of its clinical presentation.

Orbitozygomatic approach by transposition of temporalis muscle and one-piece osteotomy

BACKGROUND

A more simplified and easier technique for the orbitozygomatic approach is sought. We have developed a new modification to fully expose the temporal base before using one-piece craniotomy.

METHODS

By transposing the temporalis muscle underneath the zygomatic arch before osteotomy, the temporal base and the inferior orbital fissure can be fully exposed. Craniotomy is made in one piece with the frontotemporal and orbitozygomatic bone together by using a high-speed drill.

RESULTS AND CONCLUSIONS

Osteotomy was easy and the cosmetic result was satisfactory. This technique also allows better access to the subtemporal region without removing the zygomatic arch.

Transcranial approach for transsphenoidal encephalocele: report of two cases

BACKGROUND

Whereas the transcranial approach has been regarded as the therapy of choice for transethmoidal encephalocele, its feasibility for transsphenoidal encephalocele has remained controversial, particularly in neonates and infants.

CASE REPORT

Two cases of transsphenoidal encephalocele operated transcranially are presented. In the first case, this 6-year-old boy underwent a transpalatal operation with repair of a cleft palate in another hospital before admission. Reoperation via the transcranial route was carried out because of postoperative recurrent meningitis. With partial resection of the anterior wall, the encephalocele could be separated from the underlying tissue, and the interspace was filled with the pericranial flap. He made an uneventful recovery and has been well for the past 3 years. The second was a 3-month-old baby with a large encephalocele filling the nasopharyngeal space. As the cleft palate was absent, the transcranial approach was employed. In this case, the herniated tissue was excised at the lowest level possible. Postoperatively, panhypopituitarism became manifest. Re-evaluation of the preoperative magnetic resonance imaging (MRI) disclosed a small mass far below the dorsum sellae, which turned out to be an anomalous pituitary gland on histologic examination.

CONCLUSIONS

The transcranial approach is considered a valid alternative for the therapy of transsphenoidal encephalocele, particularly when the transpalatal approach is unfeasible. While the anterior wall of the herniated sac may be safely resected, the posterior wall should under no circumstances be sacrificed. The preoperative MRI is essential, as it may provide valuable information as to the location of vital structures within the herniated tissue.

Biodegradation of dibenzothiophene and 4,6-dimethyldibenzothiophene by Sphingomonas paucimobilis strain TZS-7

Strain TZS-7, tentatively identified as Sphingomonas paucimobilis, was isolated from crude oil for its ability to degrade dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-dmDBT). This strain did not utilize DBT or 4,6-dmDBT as the sole source of sulfur. However, the degradative activity was induced by various aromatic compounds, including DBT, fluorene, anthracene, naphthalene and toluene. Three products formed from 4,6-dmDBT degradation were detected and two of these were proposed to be 7-methyl-3-hydroxy-2-formylbenzothiophene and 7-methylbenzothiophene-2,3-dione by gas chromatography-mass spectrometry analysis. These findings proved that 4,6-dmDBT is degraded through a ring-destructive pathway by resting cells of strain TZS-7.

Reduction in brain-derived neurotrophic factor protein level in the hippocampal CA1 dendritic field precedes the delayed neuronal damage in the rat brain

Utilizing a specific polyclonal antibody against a peptide unique for brain-derived neurotrophic factor (BDNF), we investigated the regional and temporal profiles of immunoreactivity of the BDNF protein in the rat hippocampus after transient forebrain ischemia. The pattern of immunoreactivity for the BDNF receptor (TrkB) was also examined and compared with that for BDNF. In the early phase after ischemia, we observed a distinct regional difference in immunoreactivity between the pyramidal cell layer and the stratum radiatum of the CA1 subfield. In the pyramidal cell layer, there was a rapid and transient increase in the positive immunostaining for both BDNF and TrkB. By contrast, in the stratum radiatum there was a marked decrease in BDNF immunoreactivity, but not one in that of TrkB. One week after ischemia, high immunoreactivity for both BDNF and TrkB was observed in the reactive astrocytes in the dendritic field of the CA1 subfield. These findings suggest that a transport of BDNF from the neuronal soma to the dendrites of the stratum radiatum might be ceased after the ischemic insult. Thus, a dysfunctional autocrine mechanism of BDNF within the CA1 neuron may be involved in the pathogenesis of selective neuronal damage after ischemia.

Arteriovenous malformation presenting as hypertensive putaminal hemorrhage in an elderly patient--case report

A hypertensive 72-year-old male presented with a ruptured arteriovenous malformation (AVM) manifesting as hematoma indistinguishable from common putaminal hemorrhage on precontrast computed tomography scan. The AVM was located in the proximal sylvian region fed by branches of the anterior and middle cerebral arteries. The AVM was totally removed. Although bleeding from AVM in the elderly is uncommon, the cause of even common hypertensive hemorrhage should be identified by other imaging techniques such as magnetic resonance imaging and cerebral angiography to allow the optimum treatment.

The effect of bosentan, a new potent endothelin receptor antagonist, on the pathogenesis of cerebral vasospasm

Using the canine chronic cerebral vasospasm model, we studied the effects of a potent new nonpeptidic endothelin-1 (ET1) receptor antagonist, bosentan (Ro 47-0203, 4-tert-butyl-N-[6-(2-hydroxy-ethoxy)-5-(2-methoxy-phenoxy)-2,2'-bipyr imidin-4 - yl]-benzenesulfonamide). Endothelin (ET) receptors are composed of the ETA receptors and the ETB receptors; ET1 acts on both of these receptors. Although it has been previously thought that the ETA receptor mediates vasoconstriction, whereas the ETB receptor mediates vasodilation, recent evidence suggests that ETB receptor also contributes to vasoconstriction. Because bosentan is a mixed antagonist that acts on both receptors, its use might indicate whether or not ET is involved in the pathogenesis of cerebral vasospasm. In this study, beagle dogs received a double injection of autologous arterial blood into the cisterna magna at 2-day intervals (i.e., on Days 0 and 2). The diameter of the basilar artery (BA) was angiographically examined up to Day 7. A total of 24 dogs were randomly allocated to either the treatment group or the no-treatment group. Eight dogs were treated with 10 mg/kg bosentan by a one-dose injection into a central venous catheter. Bosentan was given twice a day starting immediately after the first subarachnoid hemorrhage for 6 days until Day 5. Sixteen dogs served as controls, with untreated subarachnoid hemorrhage. After the injection of bosetan, blood pressure decreased by about 25 mm Hg for a few minutes and then returned to normal. In the dogs treated with bosentan, the BA spasm on Day 7 was significantly ameliorated compared with the BA spasm in the untreated dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

[Highlateral approach to the lesions around the upper cervical vertebrae and foramen magnum]

In the present paper, we describe the surgical techniques of high lateral cervical approach and its feasibility for the excision of tumors located in the ventral or lateral aspect of the upper cervical vertebrae and of the craniovertebral junction. The patient is positioned laterally on the operating table, but the operator's position and the skin incision are slightly altered depending on the location of the tumor. When the lesion is situated below C1, the ipsilateral shoulder is pulled down toward the back. The operator stands rostral to the head. The attachment of the sternocleidomastoid muscle to the mastoid is detached and reflected anteriorly through a retroauricular curved skin incision. The posterior cervical muscles such as the splenius capitis, longissimus capitis, semi-spinalis capitis are detached from the occipit and retracted posteriorly. At this point, the transverse process of C1 and the articular facet of the vertebrae of C2-C4 are identified by palpation. According to the tumor location, the muscles attached to the relevant transverse processes and facets are divided and reflected posteriorly. Through careful dissection, the cervical nerve roots and the vertebral artery are exposed. The root sleeves as well as thecal sac may be exposed by resecting the posterior two-thirds of the superior and inferior articular facets and the adjacent laminae of the vertebrae. In case the whole facet was removed, an iliac bone graft is placed between the remaining transverse processes and the laminae above and below for fixation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Anterior transcallosal approach for the mass lesions in and around the third ventricle: with particular reference to the method of enlarging the foramen of Monro]

Enlargement of the foramen of Monro is an essential maneuver to obtain an appropriate surgical view when large, solid lesions in and around the third ventricle are to be removed via the anterior transcallosal approach (ATA). For this purpose, three methods, i.e., the subchoroidal, transchororidal, and transfornicial approaches have so far been reported. However, since the locations and the pathological natures of space occupying lesions in this region are widely variable, the indication as well as the feasibility of each approach has remained rather unclear. The present paper deals with our surgical experience with six patients (2 gliomas, 1 angioma, 1 AVM, 1 plexus papilloma, 1 basilar top aneurysm) operated on using the ATA in which variable methods of enlarging the foramen of Monro were employed. Aiming at complete removal or clipping of the lesion, the seemingly best among the above three approaches was determined preoperatively, considering the size, location, and pathological nature of the lesion. The shape of the choroid plexus of the roof of the IIIrd ventricle as revealed by MRI was also taken into account. The subchoroidal, transchoroidal, and the transfornicial approaches were employed in 3, 2, and 1 cases, respectively. Except for one glioma which ended up being removed extensively, all the tumors and AVM were totally removed and the aneurysm successfully clipped. From the above experience, the merits and demerits of each approach for different types of lesions are discussed in view of their suitability for achieving total removal.(ABSTRACT TRUNCATED AT 250 WORDS)

[Reduction cranioplasty for a case of intractable chronic subdural hematoma in infancy]

Although almost all infants suffering chronic subdural hematomas (CSDH) are successfully treated by established methods such as a subdural puncture, burr holes and shunting procedures, infantile CSDH with progressive craniocerebral disproportion requires a special therapeutical regimen. Clinical efforts such as reduction cranioplasty have been made as a treatment for these cases. This is a case report of a 9-month-old male infant with an intractable CSDH, bilateral and large, and subsequent brain atrophy caused by traumatic head injury. Excellent results were obtained by a modified reduction cranioplasty. In brief, the patient was supine-positioned with a 20-degree flexion of the head in an attempt to obtain a large operative field. Bicoronal skin incision was combined with an additional linear one on the midline (T-shaped incision). Bilateral frontoparietal craniotomy with periosteum was made to keep the midline bony bridge overlying the superior sagittal sinus (SSS). The resulting extensive dural opening allowed complete evacuation of the subdural hematoma. Thereafter, the anterior part, ca. 4cm in width, of the bony bridge was removed in order to make the remaining bone able to be manipulated and connected to the frontal bone. Prior to this stage, SSS close to the crista galli was ligated and cut with the falx to avoid postoperative kinking. The dura mater was sutured so as not to leave an excessive subdural space. The bone flaps were trimmed to complete a good-shaped reconstruction. Finally, the excessive scalp was removed because the original scalp was too large for the reconstructed skull.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of nerve growth factor content levels after transient forebrain ischemia in gerbils

Involvement of nerve growth factor (NGF) in the pathogenesis of delayed neuronal death (DND) of CA1 neurons in the hippocampus has been suggested. We measured regional changes in the content of tissue NGF of the hippocampus in the Mongolian gerbil after 5 min forebrain ischemia. The NGF content was found to decrease significantly in the CA3 and dentate regions by 32% two days after ischemia. By contrast in the CA1 region, the level of NGF became significantly elevated by 50% two weeks after ischemia or later. The early reduction of NGF content in the afferent area projecting to the CA1 sector might be primarily linked to the pathogenesis of DND, whereas the delayed increase within the CA1 sector might be a secondary local response mainly of reactive astroglia.

Delayed traumatic intracerebellar hematoma: correlation between the location of the hematoma and the pre-existing cerebellar contusion--case report

A rare case of delayed traumatic intracerebellar hematoma (DTIC1H) in a 54-year-old male achieved an excellent outcome without surgery. Analysis of this case and other reported cases suggests that DTIC1H occurs in two types: Group I with hematoma developing in previously contused areas, and Group II with hematoma developing in areas appearing normal on the initial computed tomographic scan. Group I hematomas occurred in the cerebellar cortex, but Group II hematomas occurred in the subcortical region or vermis where direct impact is less likely to have an effect. This suggests different mechanisms of development for DTIC1H.

Amelioration of delayed neuronal death in the hippocampus by nerve growth factor

Selective neuronal death in the CA1 sector of the hippocampus [delayed neuronal death (DND)] develops several days after transient global cerebral ischemia in rodents. Because NGF plays a potential role in neuronal survival, it was decided to study its effect in DND. We report here that intraventricular injection of NGF either before or after 5 min forebrain ischemia in the Mongolian gerbil significantly reduced the occurrence of DND. The tissue content of NGF in the hippocampus was decreased 2 d after ischemia and recovered to the preischemic level by 1 week. By the Golgi staining technique, changes first began in the dendrites of affected neurons as early as 3 hr. Such changes could be ameliorated by NGF treatment. Although previous knowledge of NGF is limited to the survival of cholinergic neurons in the CNS, it is assumed that other mechanisms must be operating in the hippocampus, for example, postsynaptic modification at dendrites or aberrant expression of NGF receptors possibly at the initial excitation period by glutamate. Furthermore, because previous work has shown that inhibition of protein synthesis reduces the occurrence of DND, a program leading to cell death might also be operating via de novo synthesis of certain protein(s), collectively termed "killer protein," because of a lack of NGF.

Prevention of cerebral vasospasm by actinomycin D

The role of endothelin, a newly found vasoconstrictor peptide, is examined in the pathogenesis of cerebral vasospasm after experimental subarachnoid hemorrhage (SAH) in the dog. Endothelin immunoreactivity was overexpressed in the endothelium of the vasospastic basilar artery. Because endothelin synthesis is regulated at the messenger ribonucleic acid transcription level, the effect of actinomycin D, a ribonucleic acid synthesis inhibitor, was studied as a means of preventing vasospasm. It was found that treatment with intravenous actinomycin D for 5 days beginning on the day of SAH completely inhibited the development of vasospasm. This novel experimental therapy may lead not only to the elucidation of the pathogenesis of cerebral vasospasm but also to the availability of a prophylactic adjuvant therapy for patients with SAH.

Endothelins: vasoconstrictor effects and localization in canine cerebral arteries

1. The vascular effects of endothelin and localization of endothelin-like immunoreactivity were characterized in isolated cerebral arteries of dogs. 2. Endothelin-like immunoreactivity was detected in a few populations of endothelial cells of dog basilar artery. 3. Endothelin-1, endothelin-2 and endothelin-3 contracted isolated ring preparations of cerebral arteries in a dose-dependent manner independently of the presence of endothelium. The ED50 values (and 95% confidence intervals) for the contraction were 411 pM (242-697 pM) and 478 pM (295-776 pM) for endothelin-1 and endothelin-2, respectively. Endothelin-3 induced vascular contraction at a higher concentration (ED50 = 26.5 nM, 95% confidence interval = 15.7-45.7 nM). 4. The increases in tone induced by endothelin-1 and endothelin-2 did not return to the resting level after repeated washings, while a rinse with Krebs solution reversed the vasoconstrictor response to endothelin-3. The endothelins did not cause any vasodilator response in arteries precontracted with uridine 5'-triphosphate even in the presence of intact endothelial cells. 5. NiCl2 (1 mM) attenuated the contractions induced by endothelin-3 (10-300 nM) and those to relatively low doses (1 nM) but not higher doses (10-100 nM) of endothelin-1 and endothelin-2. The contractions in response to endothelin-1, endothelin-2 and endothelin-3 were greatly attenuated in Ca(2+)-free solutions although high concentrations of endothelin-1 and endothelin-2 still evoked contractions. 6. These results suggest that the vasoconstriction induced by endothelin-3 and lower doses of endothelin-1 and endothelin-2, largely depends on the influx of Ca2+ ions. The apparent insensitivity to Ni2+ shows that additional distinct mechanisms also operate in the vasconstrictor responses to high concentrations of endothelin-1 and endothelin-2. 7. The presence of endothelin-like immunoreactivity in endothelial cells suggests that endothelin is a potential endogenous spasmogen.

Possible role of endothelin in the pathogenesis of cerebral vasospasm

Since the discovery of endothelin-1 (ET-1), its involvement in cerebral vasospasm after subarachnoid hemorrhage (SAH) has been suspected. We performed various experiments, first to demonstrate the presence of ET in both patients and dogs with SAH, and second to examine the effects of ET synthesis inhibition in experimental vasospasm. Here we report that ET was present in both plasma and cerebrospinal fluid (CSF) in SAH, but did not correlate with vasospasm. However, ET was locally expressed in the vascular endothelium in vasospasm. Several therapeutic approaches causing the inhibition of ET synthesis were effective in preventing the development of vasospasm. Such approaches utilized drugs that inhibited RNA and DNA synthesis. Among them, actinomycin D treatment was most effective. We also utilized phosphoramidon, a recently found conversion inhibitor of big ET to ET. However, this product failed to ameliorate the development of vasospasm. Therefore, although we cannot yet conclude that ET is the main cause of cerebral vasospasm, it may, at least, act as one of the modifying factors in cerebral vasospasm.

Characterization of the effect of endothelins in canine cerebral arteries

In a few populations of endothelial cells of dog basilar arteries, endothelin (ET)-like immunoreactivity was detected to be present. ET-1, ET-2, and ET-3 caused vasoconstrictor responses but not vasodilator responses in isolated ring preparations of dog cerebral arteries in vitro. The ED50 values for the contractions were 411 pM, 478 pM, and 26.5 nM for ET-1, ET-2, and ET-3, respectively. NiCl2 (10(-3) M) attenuated the contractions induced by ET-3 (10(-8)-3 x 10(-7) M) and those to relatively low doses (10(-9) M) but not higher doses (10(-8)-10(-7) M) of ET-1 and ET-2. The contractions in response to ET-1, ET-2, and ET-3 were greatly attenuated in Ca(2+)-free solutions, although high concentrations of ET-1 and ET-2 still evoked contractions. These results suggest that the vasoconstriction induced by ET-3 and lower doses of ET-1 and ET-2 largely depends on the influx of Ca2+ ions. Furthermore, additional distinct mechanisms may contribute to the vasoconstrictor effects of high concentrations of ET-1 and ET-2. The presence of endothelin-like immunoreactivity in endothelial cells suggests that endothelin is a potential endogenous spasmogen.

Reduction of delayed neuronal death by inhibition of protein synthesis

Brief forebrain ischemia in rodents causes delayed neuronal death selectively in the CA1 pyramidal cells of hippocampus. Treatment with a reversible protein synthesis inhibitor, anisomycin, significantly reduced the occurrence of delayed neuronal death in the Mongolian gerbil. This result indicates that de novo synthesis of certain protein(s), collectively termed 'killer protein' is required, possibly due to deprivation of nerve growth factor or other trophic factors.

Effect of recombinant human lipocortin I on brain oedema in a rat glioma model

Glucocorticoids have been extensively used to treat brain oedema, but little is known on the mechanisms of steroids in the prevention and resolution of tumour-induced brain oedema. Recently, the mechanism of steroid action is thought to involve synthesis of proteins with antiphospholipase activity called lipocortins. In a previous study, we have demonstrated the efficacy of dexamethasone (DEX) in resolving peritumoural oedema in a rat glioma model. Using the same model, we studied the effect of recombinant human lipocortin I on the resolution of peritumoural oedema. Intracerebral tumours were produced in 6-week-old Wistar rats by implantation of rat glioma C6 cells. In comparison with sham-operated controls, the tumour-implanted animals showed significant increase in the cortical water content, which was reduced by DEX administration to the level in the sham-operated controls. The water content within the tumour was also significantly decreased by DEX treatment. On the other hand, there was no difference in water content between lipocortin-treated and non-treated animals. These findings suggest that tumour-induced brain oedema can be reduced by DEX treatment but not by lipocortin. In conclusion, it is doubtful whether glucocorticoids exert their action in resolving brain oedema by inducing PLA2 inhibitory proteins named lipocortins.

Endothelin acts in feline and canine cerebral arteries from the adventitial side

We investigated the in vivo vasoconstrictor effect of endothelin, a recently characterized vasoconstrictor peptide from vascular endothelium, in the basilar arteries of five cats and five dogs. Basilar artery caliber was angiographically measured under anesthesia before (control) and after either vertebral artery infusion or cisternal injection of the peptide. In cats, 5-500 pmol endothelin induced a dose-dependent basilar artery contraction in vivo when injected intracisternally; within 3 minutes after injection of 500 pmol endothelin, basilar artery caliber was decreased by 73 +/- 4% compared with control diameter before injection. The vasoconstriction was extremely long-lasting; no significant recovery of basilar artery caliber was observed for up to 2 hours after injection. In contrast, infusion of up to 3,000 pmol endothelin into the vertebral artery had no appreciable effect on basilar artery caliber. Similar results were obtained in dogs; vasoconstriction was maintained for as long as 12 hours. Our observations suggest that endothelin acts in cerebral vessels from the adventitial side, not from the luminal side, possibly due to the presence of the blood-arterial wall barrier. The long-lasting nature of endothelin-induced constriction of the cerebral arteries in vivo suggests that the peptide might be involved in the pathogenesis of cerebral vasospasm.

Effect of enhanced capillary activity on the blood-brain barrier during focal cerebral ischemia in cats

We hypothesize that enhanced activity of capillary Na,K-ATPase promotes Na+ influx into the brain and causes early edema formation in focal cerebral ischemia. The pharmacologic suppression of brain capillary Na,K-ATPase as a means to ameliorate edema formation was examined using the middle cerebral artery occlusion model in 36 cats. With the help of a catheter inserted into the middle cerebral artery, the ischemic brain area was directly perfused with 10(-5) M ouabain. Perfusion was maintained as intermittent 15-second pulse injections given every 5 (n = 6) or 2 (n = 6) minutes. By this method, the naturally occurring circulatory conditions during ischemia were not altered. Four hours after ischemia, the cortical specific gravity at each of six locations over the ischemic area was compared with the corresponding ischemic blood flow measured by the H2 clearance technique. The results show that ouabain perfused every 2 minutes significantly ameliorated edema formation compared with six control cats perfused with Krebs-Ringer solution. In a separate series of experiments, the Na+ flux across the blood-brain barrier was studied by injecting 22NaCl together with an intravascular reference (cobalt-57-labeled microspheres 15 microns in diameter) into the ischemic area. The brain uptake index of 22Na was markedly increased in the ischemic cortex of six control cats; ouabain treatment in six cats suppressed the increase of Na+ influx. The results support our hypothesis that brain capillary Na,K-ATPase activity increases during early focal ischemia, leading to enhanced Na+ together with H2O flux across the blood-brain barrier.

Prostaglandin profiles in relation to local circulatory changes following focal cerebral ischemia in cats

We explored the temporal and topographic relations between local cerebral blood flow and regional brain prostaglandin profile following prolonged or transient occlusion of the middle cerebral artery in cats. Each experimental group was subjected to a sham operation, prolonged ischemia, or recirculation. Local cerebral blood flow was measured by the hydrogen clearance method. Following in situ freezing, cortical samples were obtained from each gyrus for determination of prostaglandin (PG) F2 alpha, PGE2, 6-keto-PGF1 alpha, and thromboxane (TX) B2 concentrations by radioimmunoassay. During prolonged ischemia, the concentrations of PGF2 alpha and PGE2 within the middle cerebral artery territory were significantly increased. Immediately after recirculation, there was a prominent but transient increase in PGF2 alpha and PGE2 in gyri that had been exposed to moderate ischemia (perifocal area). By contrast, the increases in these prostaglandins were slow and less prominent in gyri that had been exposed to severe ischemia (the focal area). The concentration of 6-keto-PGF1 alpha did not change during prolonged ischemia but transiently increased following recirculation in both the focal and perifocal areas. The TXB2 concentration did not change in any experimental group. Our study revealed a homogeneous increase in the regional brain content of PGE2 or PGF2 alpha in spite of the heterogeneous reduction of local cerebral blood flow during prolonged ischemia. Following recirculation, the focal and perifocal areas exhibited different patterns of prostanoid content. No correlation was found between local cerebral blood flow and the regional concentration of any prostaglandin examined.

The role of free radicals and eicosanoids in the pathogenetic mechanism underlying ischemic brain edema

Results of our consecutive study on the pathogenic mechanism underlying ischemic brain edema are summarized in this paper. Pertinent findings are as follows: (1) there is a close correlation between the influxes of water and sodium following ischemia; (2) the edema fluid can be regarded as the ultrafiltrate of serum; (3) there is a significant increase in the brain content of HETEs following ischemia; (4) the lipoxygenase activity of brain microvessels is increased following ischemia; (5) the lipoxygenase activity as well as the Na+, K+-ATPase activity of brain microvessels are enhanced by a hydroperoxide, 15-HPETE; (6) inhibition of Na+, K+-ATPase of brain microvessels by intraarterial infusion of ouabain resulted in a significant decrease in edema formation; and (7) not the cyclooxygenase, but the lipoxygenase pathway seems to be involved in the enhancement of microvessel Na+, K+-ATPase. Lipoxygenase(s) and Na+-K+-ATPase of brain microvessels, the activities of which are enhanced by an increased level of free radicals and/or hydroperoxides, may play a significant role in the occurrence of ischemic brain edema.