Toshihiro Takaba

Surgical lead-preserving procedures for pacemaker pocket infection

BACKGROUND In the treatment of pacemaker pocket infection, removal of the entire pacing system has been considered necessary to avoid recurrent infection. We report a series of patients treated surgically by our lead-preserving procedures. METHODS Between 1990 and 2001, a total of 18 patients underwent one of two types of lead-preserving procedures. Procedure 1 preserves the full length of the lead, and procedure 2 preserves only the distal part of the lead. Signs of bacteremia, endocarditis, or purulent material within the lead insulation preclude application of these procedures in patients with potential or definite pacemaker pocket infection. RESULTS Seventeen patients who met the indications for our procedures were discharged 7 to 14 days (8.9 +/- 2.4 days, mean +/- SD) postoperatively without signs of infection and were followed up for a total of 987 patient-months until the close of the study or death without recurrent infection. The remaining 1 patient, who did not meet the indications, suffered reinfection soon after the operation. CONCLUSIONS The follow-up data suggest that our lead-preserving procedures should be considered as alternatives to conventional removal of the entire pacing system in cases of pocket infection that meet specific criteria.

Tumor dimension and prognosis in surgically treated lung cancer: for intentional limited resection.

Tumors with a maximum dimension of 3 cm are categorized as T1, whereas those greater than 3 cm are T2 by TNM classification. Some physicians suggest that early-stage peripheral lung cancer should have a maximum tumor diameter of 2 cm and that limited surgery (segmentectomy without lymph node dissection) is acceptable for the patients. In this study, the relationship between the tumor dimension and prognosis was analyzed in 207 patients with surgically treated primary non–small-cell lung cancer (SCLC). The 5-year survival rate of those with tumors 3 cm or less and without lymph node (LN) metastases was 86%, which was significantly higher than that of those with tumors more than 3 cm and without hilar and mediastinal LN metastases (65%) (p < 0.05). However, 33% of the patients with tumors 3 cm or less had LN metastases, and the 5-year survival rate did not differ between those with tumors 3 cm or less (60%) and those with tumors more than 3 cm (54%). Twenty-eight percent of patients with tumors 2 cm or less had LN metastases, and the 5-year survival rate of the patients with tumors 2 cm or less was 62%. The 5-year survival rate of those with tumors 2 cm or less and without LN metastases was 88%. Forty-six patients with tumors 2 cm or less included 5 cases with an intrapulmonary metastasis in the same lobe (11%). In conclusion, a size of 3 cm is an appropriate boundary as the T factor. Because those with tumors 2 cm or less have a relatively high percentage of LN metastases, intraoperative frozen sections of LN should be considered for those undergoing limited surgery for primary non-SCLCs 2 cm or less. Intrapulmonary metastases also should be considered for those undergoing limited surgery even if the maximum dimension of the primary tumor is less than 2 cm.

Analysis of the anatomic changes in the thoracic cage after a lung resection using magnetic resonance imaging.

The thoracic cage after a lung resection is filled by the remaining lobes, the elevated diaphragm, the diminished thoracic cage, and by mediastinal shifting. The changes in the thorax after a lung resection were quantified using magnetic resonance imaging. The study group consisted of 39 patients who had undergone a lobectomy, four who had undergone a pneumonectomy, and 14 controls. The left ventricular angle, ascending aortic angle, mediastinal shift, longitudinal length of the thoracic cage, the distance between the thoracic apex and the level of the aortic valve, and diaphragmatic elevation were all measured. After a right lower lobectomy, the mediastinum shifted more rightward than after a right upper lobectomy. The diaphragm became more greatly elevated after a right upper lobectomy than after a right lower lobectomy. When a chest wall resection was added to a right upper lobectomy, the mediastinal anatomical changes decreased. After a left upper lobectomy, the degree of mediastinal shifting was greater than after a left lower lobectomy. A left upper lobectomy shifted the mediastinum at the level of the right atrium. This method is easily reproducible and was found to be effective for quantifying the changes in the thorax after a lung resection.

Atrophy of the abdominal wall muscles after extraperitoneal approach to the aorta

OBJECTIVE We retrospectively assessed computed tomography (CT) scans to determine degree of anterolateral abdominal muscle atrophy in patients who underwent infrarenal aortic repair with 2 kinds of incisions for the extraperitoneal approach. METHODS CT scans obtained before surgery and final scans obtained 2 to 100 months after surgery were assessed in 12 patients with paramedian incision (PM group) and 27 patients with flank incision (F group) who could be followed up at our hospital. We considered muscle thickness before surgery on the incision side to be 100% thickness (baseline value), and we calculated, by measuring the incision side after surgery, the corrected percent thickness (CPT%), which represents percentage of remaining muscle thickness that has escaped incision-induced atrophy. CT scans obtained at the level of the third (L3) and fifth (L5) lumbar vertebrae and the center of the sacrum (S) were selected for CPT% measurement. RESULTS Duration from surgery to final CT scan was 2 to 65 months (mean +/- SD, 34.33 +/- 21.38 months) in PM group and 3 to 96 months (27.85 +/- 20.74 months) in F group. In PM group, mean CPT% values of the rectus abdominis muscle were 55.83 +/- 21.65% at L3, 35.50 +/- 10.79% at L5, and 31.92 +/- 11.00% at S; these values were statistically much smaller than baseline (P <.01). Mean CPT% values of the lateral abdominal muscles were not statistically different from baseline. In F group, mean CPT% values of the rectus abdominis muscle were 82.19 +/- 23.15% at L5 and 64.41 +/- 31.34% at S; these values were statistically smaller than baseline (P <.01). Mean CPT% values of the lateral abdominal muscles were 87.59 +/- 22.30% at L3 and 84.59 +/- 26.90% at L5; these values were statistically smaller than baseline (P <.05). CONCLUSIONS Paramedian incision induced severe rectus abdominis muscle atrophy. Although flank incision induced various degrees of atrophy in both muscles, some patients had no muscle atrophy. These data indicate that further anatomic investigation into the relation between flank incision and abdominal wall innervation may contribute to prevention of muscle atrophy after flank incision.

Outcome Following Surgery for Primary Lung Cancer with Interlobar Pleural Invasion

PurposeTo determine whether interlobar pleural invasion into the adjacent lobe (interlobar P3) should be assessed as T3 according to the tumor-node metastasis classification.MethodsSurgically treated patients with primary lung cancer (n = 322) were analyzed.ResultsTumors with interlobar P3 had a significantly lower incidence of mass screening detection, a higher occurrence rate of squamous cell carcinoma, and a larger tumor diameter than tumors without interlobar P3. The lymph node metastatic rate did not differ between the patients with and without interlobar P3. The 5-year survival rate of patients with interlobar P3 was 63% and the rates of other patients were 56% with T1 disease, 57% with T2, 31% with T3, and 19% with T4. The survival rate for patients with interlobar P3 was higher than for those with T3 without interlobar P3 (P < 0.05). The 5-year survival rate of the patients with interlobar P3 was lower in adenocarcinoma (39%) than in squamous cell carcinoma (69%, P < 0.01). The results were similar when the analysis was restricted to patients without lymph node metastasis. In adenocarcinoma, the survival rate for interlobar P3 was between the rates for T2 (53%) and T3 (13%) without interlobar P3, whereas in squamous cell carcinoma, the survival rate for interlobar P3 was between the rates for T1 (88%) and T2 (54%) without interlobar P3.ConclusionTumors with interlobar P3 should be classified as T2 only in squamous cell carcinoma.

Spontaneous rupture of the iliac vein: report of a case

We reprot a rare case of a spontaneous rupture of the iliac vein which was then surgically treated with good results. A 66-year-old woman was admitted complaining of leg swelling and lower abdominal pain. On the 3rd day after admission, an operation was performed because of a gradually increasing hematoma in the retroperitoneal space. Laparotomy revealed a 17 mm longitudinal tear on the anterior surface of the left external iliac vein with a thrombus inside the lumen. Most of the previously reported 14 cases of this nature have required emergency operations.

CHANGES IN LUNG LOBAR VOLUME AND BRONCHIAL DEFORMITY AFTER RIGHT UPPER LOBECTOMY

To explore the anatomical repositioning of the middle lobe following right upper (RU) lobectomy, we measured the lobar volumes of the lung and the branching angles of the airway, and defined their changes after RU lobectomy in a rabbit model. Groups A1 (n=10) and A2 (n=10) were control groups and groups B1 (n=10) and B2 (n=10) underwent RU lobectomy. Casting material was introduced into the airway and a heart-lung bloc was removed form the thoracic cavity in all groups. In groups A1 and B1, the volume of each lobe of the bilateral lungs was measured, while in groups A2 and B2, bronchial casts were made and the branching angles of the airway were measured. The volume ratio of the right upper lobe (RUL) to the total lung was 12.0 ± 0.4% in group A1; however, after RU lobectomy, the volume ratio of the right middle lobe (RML) to the total lung increased from 8.7 ± 0.6% in group A1 to 13.5 ± 0.8% in group B1. The volume of the left lung also increased from 43.0 ± 0.5% in group A1 to 48.8 ± 1.1% in group B1. The angle between the truncus intermedius and the RML bronchus was significantly smaller in group B2, at 109.0 ± 3.5°, than in group A2, in which it was 138.5 ± 1.7°. The angle between the RML bronchus and the coronal plane was 57.5 ± 2.5° in group A2 and 33.5 ± 3.3° in group B2. Our method of measuring the bronchial branching angle subsequent to RU lobectomy proved useful to illustrate postoperative positional changes and expansion of the remaining lobes.

Extended surgery with en bloc resection of the right common iliac vessels for lymph node metastasis of mucinous colon carcinoma: report of a case.

Abstract We report herein the case of a 63-year-old woman who underwent surgery for recurrent mucinous carcinoma of the cecum. Recurrent metastatic lymph nodes had invaded the right common iliac vessels and right ureter, but she had no distant metastases and no peritoneal dissemination. Extended surgery with en bloc resection of the right iliac vessels and right ureter, and femorofemoral bypass were performed. Postoperatively, several complications developed which were successfully treated by further operations. By 1 year after surgery, she had no recurrent tumors on radio-logical examination, suggesting that our aggressive surgery with resection of the invaded regional vessels had effectively removed the recurrent tumors. This procedure may therefore significantly prolong the survival time and improve the quality of life of such patients.

Benign solitary fibrous tumor of the parietal pleura which invaded the intercostal muscle

A 29-year-old woman who underwent evaluation for a 3-month history of left-sided back pain proved to have a left pleural tumor accompanied by a bloody pleural effusion (cytological class II). Three years previously, a chest roentgenogram had been normal. The tumor originated from the parietal pleura at the level of the first three intercostal muscles and was excised completely in continuity with these muscles, including a margin of normal muscle. The tumor measured 15x12 cm and the pathologic diagnosis was benign solitary fibrous tumor; while the tumor invaded the intercostal muscles, no histologically malignant features were present. Long-term follow-up is planned because a possibility of local recurrence exists.

Effects of Initial Low Flow Reperfusion and Surfactant Administration on the Viability of Perfused Cadaveric Rat Lungs

Abstract. To expand the cadaveric lung donor pool, protecting the endothelium and alveoli from warm ischemia and reperfusion injury is important. The effects of initial low flow reperfusion and surfactant administration were studied in non–heart-beating donor lungs. The rat heart-lung bloc was excised immediately (group 1) or 30 min (groups 2–4) after euthanasia (n= 6 in each group). The graft was ventilated and reperfused (50 ml/min) immediately after excision for 1 h in groups 1 and 2. In groups 3 and 4, the reperfusion flow rate was increased gradually to 50 ml/min, while ensuring that the pulmonary arterial pressure did not exceed 40 mmHg. Then the graft was reperfused for 1 h. Surfactant was introduced into the airway in group 4 before reperfusion. Airway pressure (AWP) and pulmonary arterial pressure were monitored during reperfusion. After reperfusion, the wet/dry weight ratio (W/D) of the right lung was calculated, and histologic examination using trypan blue staining of the left lung was performed. In group 2, lung failure appeared in all animals during reperfusion. In group 3, although all lungs were reperfused for 1 h, AWP and W/D were higher than in group 1. In group 4, AWP and W/D were lower than in group 3. Histologic examination showed that surfactant administration had attenuated the alveolar cell death. To avoid damage caused by high pulmonary arterial pressure associated with graft reperfusion, iniital low flow reperfusion was beneficial in cadaveric lungs. Surfactant administration before reperfusion was effective in preventing pulmonary edema.