Kazuo Tanoue

Effects of endoscopic injection sclerotherapy on portal hypertensive gastropathy: a prospective study

The effect of endoscopic injection sclerotherapy (EIS) for esophageal varices on portal hypertensive gastropathy (PHG) was investigated in 137 patients who underwent EIS from July 1987 to March 1990. Two groups, PHG(+) (N = 35) and PHG(-) (N = 102) were distinguished by endoscopic findings obtained before EIS. PHG was classified into four grades by endoscopy scored as 0, 1, 2, or 3. The PHG score significantly worsened after EIS (p < 0.01), and PHG became worse 6 to 9 months after the eradication of varices followed by gradual improvement. Recurrent small veins, which required additional EIS, appeared more frequently in the PHG(+) group (p < 0.05). New gastric varices appeared or gastric varices enlarged after EIS more frequently in the PHG(+) group (7 patients, 20.0%) than in the PHG(-) group (12 patients, 11.8%), but this was not statistically significant. Thus, frequent endoscopy after EIS is needed with special attention directed to development of PHG and gastric varices, especially for patients with PHG prior to treatment.

Endoscopic ligation of esophageal varices compared with injection sclerotherapy : a prospective randomized trial

Fifty cirrhotic patients with esophageal varices underwent endoscopic treatment in a prospective randomized trial carried out to compare variceal ligation with injection sclerotherapy, with respect to safety, efficacy, and complications in the initial session. Twenty-five patients each were treated using endoscopic variceal ligation or endoscopic injection sclerotherapy in the initial session and then only endoscopic injection sclerotherapy for all following sessions. Ligations numbered 4.1 at the initial session. The total number of sessions of endoscopic injection sclerotherapy was 4.0 +/- 1.3 in the endoscopic injection sclerotherapy group compared with 3.6 +/- 1.4 in the endoscopic variceal ligation group. The total volume of the sclerosant used by the end of all the sessions was 23.9 +/- 10.3 ml in the endoscopic variceal ligation group and 39.0 +/- 11.5 ml in the endoscopic injection sclerotherapy group (p < 0.0001). In all patients, complete eradication of the varices was achieved, and at 7 to 15 months follow-up no evidence of recurrence was seen. Adverse effects such as pyrexia, chest pain, and pleural effusion after the initial session were significantly lower in the endoscopic variceal ligation group (p < 0.05), and total bilirubin, serum creatinine, lactate dehydrogenase, and urinary beta 2-microglobulin were significantly increased and PaO2 decreased after endoscopic injection sclerotherapy (p < 0.05). This study shows that endoscopic variceal ligation significantly decreased the adverse effects associated with endoscopic injection sclerotherapy in the initial session, and it is recommended as an alternative to sclerotherapy.

Role of the spleen in liver fibrosis in rats may be mediated by transforming growth factor β-1

Background: The effect of the spleen on the cirrhotic liver is unknown.
 Transforming growth factor‐β1 (TGF‐β1), which plays a crucial role in the matrix production during liver fibrosis, is an inhibitory factor regarding the regeneration of hepatocytes. In this study, we investigated the TGF‐β1 production in the spleen of cirrhotic rats and the effects of a splenectomy on the healing process from liver fibrosis.

Construct validity for eye-hand coordination skill on a virtual reality laparoscopic surgical simulator.

BackgroundThis study was carried out to investigate whether eye-hand coordination skill on a virtual reality laparoscopic surgical simulator (the LAP Mentor) was able to differentiate among subjects with different laparoscopic experience and thus confirm its construct validity.MethodsA total of 31 surgeons, who were all right-handed, were divided into the following two groups according to their experience as an operator in laparoscopic surgery: experienced surgeons (more than 50 laparoscopic procedures) and novice surgeons (fewer than 10 laparoscopic procedures). The subjects were tested using the eye-hand coordination task of the LAP Mentor, and performance was compared between the two groups. Assessment of the laparoscopic skills was based on parameters measured by the simulator.ResultsThe experienced surgeons completed the task significantly faster than the novice surgeons. The experienced surgeons also achieved a lower number of movements (NOM), better economy of movement (EOM) and faster average speed of the left instrument than the novice surgeons, whereas there were no significant differences between the two groups for the NOM, EOM and average speed of the right instrument.ConclusionsEye-hand coordination skill of the nondominant hand, but not the dominant hand, measured using the LAP Mentor was able to differentiate between subjects with different laparoscopic experience. This study also provides evidence of construct validity for eye-hand coordination skill on the LAP Mentor.

Risk factors for portal venous thrombosis after splenectomy in patients with cirrhosis and portal hypertension.

Portal venous thrombosis (PVT) is a potentially fatal complication following splenectomy. Its mechanisms and risk factors are poorly understood, especially in patients with cirrhosis and portal hypertension. This study investigated risk factors for PVT following splenectomy in such patients.

Laparoscopic gastric devascularization and splenectomy for sclerotherapy-resistant esophagogastric varices with hypersplenism

BACKGROUND The combination of sclerotherapy with surgical salvage for sclerotherapy-resistant esophagogastric varices has recently received much attention, however, the longterm results after such an operation have yet to be reported. This is a preliminary report of a laparoscopic adaptation of a previously described surgical procedure for the treatment of refractory esophagogastric varices. STUDY DESIGN Laparoscopic gastric devascularization and splenectomy (Hassabs operation) was successfully performed to treat recurrent sclerotherapy-resistant giant esophageal varices (n=4) and recurrent rebleeding gastric varices (n=6). The patients included 8 men and 2 women who ranged in age from 35 to 67 years (average, 54.2 years). The procedure and clinical results were evaluated from various viewpoints. RESULTS The duration of the operation ranged from 200 to 400 minutes (mean+/-standard deviation; 287.5+/-66.0 minutes) and blood loss from 10 to 1,500 mL (average, 515.5+/-507.9 mL). The weight of the spleen ranged from 500 to 850 g (average 608.0+/-126.6 g). Conversion to minimal open operation with a gasless lifting method was done in 1 patient because of uncontrolled bleeding from the splenic vein. There were no other major complications either intraoperatively or postoperatively. All patients had hypersplenism; preoperative platelet counts ranged from 1.6 to 6.8 x 10(4)/microL (average, 4.5+/-2.7 x 10(4) microL) and the postoperative count was from 5.9 to 36.0 x 10(4)/microL (average, 21.7+/-11.5 x 10(4) microL). Postoperative endoscopy revealed that varices disappeared, and no patient had recurrence of the varices after operation during the mean followup period of 12.8+/-4.1 months (average, 8 to 20 months). CONCLUSIONS The combination of laparoscopic gastric devascularization and splenectomy for sclerotherapy-resistant esophagogastric varices is considered a feasible and relatively safe surgical method for patients with hypersplenism.

Objective assessment of laparoscopic suturing skills using a motion-tracking system

BackgroundLaparoscopic suturing skills are important for advanced laparoscopic surgery. However, objective assessment of these skills has not yet been established. The aim of this study was to assess the laparoscopic suturing skills of novice and experienced surgeons using an electromagnetic motion-tracking system.MethodsA total of 18 surgeons, who were all right-handed, were divided into the following two groups according to their experience as an operator in laparoscopic surgery: 9 novice surgeons (fewer than 10 laparoscopic procedures) and 9 experienced surgeons (more than 50 laparoscopic procedures). The subjects performed an intracorporeal suturing task in an inanimate box laparoscopic trainer while the movements of their forceps were evaluated using an electromagnetic motion-tracking system. Their laparoscopic skills were assessed on the basis of the time, path length, and average speed of the forceps in each hand.ResultsExperienced surgeons completed the suturing task significantly faster than novice surgeons did. The left path length was significantly shorter for experienced surgeons than for novice surgeons, whereas the right path lengths did not differ. The right average speed of knot tying was significantly faster for experienced surgeons than for novice surgeons, whereas the left average speeds did not differ.ConclusionsEvaluation of psychomotor skills in laparoscopic suturing using an electromagnetic motion-tracking system revealed better results for experienced surgeons than for novice surgeons in terms of the time taken, left path length, and right speed of knot-tying. Furthermore, surgical proficiency due to experience can affect surgical dexterity of each hand differently. The present study also demonstrates the efficacy of this system for objective evaluation of laparoscopic suturing skills.

Effectiveness of gastric devascularization and splenectomy for patients with gastric varices

BACKGROUND Bleeding from gastric varices is difficult to control and has a high mortality rate. Recently, newly developed treatments for this serious lesion have been used, but surgical intervention is still advocated by several studies. We report our experience with gastric devascularization and splenectomy and its effectiveness for patients with gastric varices. STUDY DESIGN Gastric devascularization and splenectomy was successfully performed to treat patients with isolated gastric varices (n = 42). The patients included 27 men and 15 women who ranged from 29 to 73 years of age (average 53.7 years). We analyzed the findings of gastric varices using endoscopy, the results of gastric devascularization and splenectomy, and survival after the operation. RESULTS No patient had tortuous varices (F1). Twenty-seven patients (64.3%) had nodular varices (F2) and 15 (35.7%) had tumorous varices (F3). Twenty-five patients (59.5%) had large varices that occupied two or more areas. Twenty-nine patients (69.0%) had varices with a positive red color sign. No major complications during or after the operation were observed, and peri-operative death did not occur. Gastric varices were eradicated in all 42 patients. Survival rates were 97.6% after 1 year, 88.1% after 3 years, 76.2% after 5 years (mean followup period, 46 months). CONCLUSIONS This study showed that gastric devascularization and splenectomy provides satisfactory results for patients with gastric varices that are likely to bleed and that it can be performed even on patients who have had other treatments.

A remote surgery experiment between Japan and Thailand over Internet using a low latency CODEC system

Remote surgery is one of the most desired applications in the context of recent advanced medical technologies. For a future expansion of remote surgery, it is important to use conventional network infrastructures such as Internet. However, using such conventional network infrastructures, we are confronting time-delay problems of data transmission. In this paper, a remote surgery experiment between Japan and Thailand using a research and development Internet is presented. In the experiment, the image and audio information was transmitted by a newly developed low latency CODEC system to shorten the time-delay. By introducing the low latency CODEC system, the time-delay was shortened compared with the past remote surgery experiments despite the longer distance. We also conducted several network measurements such as a comparison between TCP/IP and UDP/IP about the control signal transmission.

Laparoscopic splenectomy for idiopathic thrombocytopenic purpura: Comparison of laparoscopic surgery and conventional open surgery

In chronic idiopathic thrombocytopenic purpura (ITP), the two main therapeutic choices are steroid treatment or splenectomy. The adult form of ITP is described as a disease found primarily in young adults, with a female predominance. Treatment with steroids effects a complete response in less than 30% of patients, whereas splenectomy is successful in more than 60% of patients who undergo it. The minimal access afforded by laparoscopic splenectomy is considered highly desirable for these patients. The purpose of this study was to compare the clinical benefits of a laparoscopic splenectomy with those of conventional open surgery for patients with ITP. From 1968 to 1993, splenectomy was performed on 51 patients: 10 operations done laparoscopically and 41 performed conventionally. Complications, postoperative pain, recovery, and hospital charges were then compared. Laparoscopic splenectomy involved minimal incisions, and a significantly lower frequency of analgesia was required for postoperative abdominal pain (1.3 vs. 3.3); hospital stay was shorter (8.2 vs. 20.1 days) (p < 0.005). Operative time was significantly longer for the laparoscopic surgery (249.2 vs. 99.8 min) (p < 0.0001), but blood loss was less (176.0 vs. 511.7 g) (p < 0.01). No intraoperative or postoperative major complications occurred with the laparoscopic procedures, compared with 46.3% with conventional surgery. Finally, the total hospital costs were lower with laparoscopic splenectomy, especially for postoperative care (p < 0.05). A laparoscopic splenectomy may well be considered the surgical treatment of choice for patients requiring a splenectomy in view of both quality of life and economy.