In vivo detection of intervertebral disk injury using a radiolabeled monoclonal antibody against keratan sulfate.

UNLABELLED: In the intervertebral disk, proteoglycans form the major part of the extracellular matrix, surrounding chondrocytelike disk cells. Keratan sulfate is a major constituent of proteoglycans. METHODS: We have radioiodinated a monoclonal antibody raised against keratan sulfate. This antibody was injected into rats (n = 6), and the biodistribution was studied. A model of intervertebral disk injury was developed, and two tail disks in each animal with both acute (2 wk old) and subacute (7 wk old) injuries were studied for in vivo antibody uptake. RESULTS: The biodistribution at 72 h was as follows: blood, 0.0018 percentage injected dose per gram of tissue (%ID/g); lung, 0.0106 %ID/g; esophagus, 0.0078 %ID/g; kidney, 0.0063 %ID/g; liver, 0.0047 %ID/g; spleen, 0.0046 %ID/g; heart, 0.0036 %ID/g; thyroid, 0.0034 %ID/g; muscle, 0.0017 %ID/g; and bone, 0.0016 %ID/g. In the subacute stage, a significant difference (P < 0.006) was found in antibody uptake between injured disks (n = 12) and adjacent healthy disks (n = 12). In vivo gamma imaging showed increased uptake in other animals having lumbar disk injuries (2, 7, and 17 d after injury). Cartilage tissue, such as the trachea, was studied separately and showed extremely high antibody uptake, 0.10 %ID/g. Rat trachea was also visualized on gamma images. CONCLUSION: Our data suggest that antibodies against nucleus pulposus components, such as proteoglycans, can be used for in vivo detection of intervertebral disk injury. This finding is in spite of the minimal circulation present in intervertebral disks.

Changing pattern of major lower limb amputations in Seinäjoki Central Hospital 1997-2000.

BACKGROUND AND AIMS: There is rather limited recent information on major amputations in Finland. Our objective was to describe the incidence of major lower limb amputations in a defined central hospital, the demographic characteristics of the amputees, diagnosis and situations leading to amputation, level of amputations and survival of the amputees after one year. MATERIAL AND METHODS: A retrospective study was undertaken on 156 patients with 169 lower limb major amputations from 1997 to 2000 at the Seinäjoki Central Hospital and Ahtäri District Hospital. RESULTS: The annual incidence of major amputations reduced from 29.5 to 15.2/100000 inhabitants. The mean age of the patients was 78.5 years but highest 80.1 in the year 2000. The reason for major amputation was chronic critical leg ischaemia with or without diabetes mellitus in 79.1% and acute ischaemia in 13.9%. The average below-knee (BK)/above-knee (AK) amputation ratio was 0.80 during the years 1997-1999 and the ratio was lowest 0.67 in year 2000. At the same year 2000 the amount of patients, whose condition was too poor for reconstructive surgery, was significantly higher than in 1997-1999. CONCLUSIONS: We suggest that BK/AK amputation ratio is decreasing in the future as the amputees tend more often to be institutionalized and immobile, and reconstruction is not an alternative and BK amputation is impossible or useless.

The effect of nitecapone on early graft function in experimental single lung transplantation.

Nitecapone is an antioxidant molecule which has been shown to protect the heart against ischemia-reperfusion injury. We investigated whether a similar effect could be detected on lung graft preservation in a porcine model of single lung transplantation. Donors received either nitecapone or placebo in a modified Euro-Collins pulmonary flush solution. After cold storage for 19 h the left lung was transplanted. Patients in the nitecapone group received a nitecapone infusion during the graft reperfusion. A right-side heart bypass was used to measure flow distribution and pulmonary vascular resistance (PVR) in the recipient's transplanted and native lungs, respectively. Pulmonary vein blood samples were analyzed for blood gases, free radical trapping capacity and diene conjugates. PVR was high in the transplanted lung, which received only 20% of the blood flow. Oxygen tension in the transplanted lung was low (2.3-26.7 kPa). Nitecapone treatment increased the plasma free radical trapping capacity threefold. In spite of this increase in antioxidative capacity nitecapone could not protect the lung against ischemia-reperfusion injury when pulmonary hemodynamics, gas exchange or plasma diene conjugates were used as measures of lung graft function.

Magnetic resonance imaging angiography in patency evaluation of bronchial artery revascularization grafts.

In this report we present our experience of non-invasive magnetic resonance imaging (MR) angiography and selective catheter angiography in assessing the patency of bronchial artery revascularization grafts after an en bloc double-lung and heart-lung transplantation. We studied 8 patients who had undergone pulmonary transplantation with direct bronchial artery revascularization. Catheter angiography was performed 10 days to 63 months postoperatively. MR angiography was performed within 24 h of the catheter procedure and the results were compared with the findings from catheter angiography. Catheter angiography showed the bronchial revascularization graft to be patent in 6 patients and occluded in 2. At MR angiography, the patency of bronchial artery revascularization grafts was reliably identified in 7 of the 8 patients. One patient had inadequate image quality because of void artefacts caused by haemostatic clips. It is concluded that MR angiography is a reliable method for assessing the patency of bronchial artery revascularization grafts.

Laser Doppler flowmetry detects early risk of tracheal anastomotic complications after lung transplantation.

Healing of tracheal anastomosis after en bloc double-lung or heart-lung transplantation was analysed with the aid of endoscopic laser Doppler flowmetry in 7 patients (group I) with successful bronchial artery revascularization (BAR) and in 5 patients (group II) without or with failed BAR. Fifteen patients undergoing coronary surgery served as a control group. Airway anastomotic index (AAI) was used to express the ratio of Doppler flowmetry values between donor and recipient airway. On postoperative day 1 the mean (range) AAI was 1.3 (1.1-1.6) in group I, 0.74 (0.25-1.0) in group II and 0.95 (0.7-1.4) in the controls.The difference was statistically significant between groups I and II (p = 0.01) and also between group I and the control group (p = 0.003). Two group II patients had low AAI (<0.5), and both developed airway anastomotic complications. We conclude that successful BAR increases blood flow in the airway anastomotic region, and that low AAI on the first postoperative day is a strong predictor of late airway anastomotic complications.

Bronchial artery revascularization improves tracheal anastomotic healing after lung transplantation.

The study aimed to clarify the role of direct bronchial artery revascularization (BAR) after en bloc double-lung (DLT) and heart-lung transplantation (HLT). Group I comprised eight patients with en bloc DLT or HLT and successful BAR, while group II included 14 DLT or HLT cases without BAR or with failed BAR. From these groups, 2 subgroups were extracted: group III, including 6 cases of en bloc DLT with successful BAR and group IV 10 HLT cases without or with failed BAR. Airway healing was evaluated at bronchoscopy and patency of BAR with angiography. Pulmonary viral, bacterial and fungal infections, rejections and bronchiolitis obliterans syndrome (BOS) were registered. Tracheal healing at 2 weeks and 3 months was better in group I than in group 1 (p = 0.003 and p = 0.05, respectively). Compared with group IV, tracheal anastomotic healing at 2 weeks was better in group III (p = 0.007) and tended to be better also after 3 months (p = 0.07). The incidence of infections, rejection or BOS did not differ between groups I and II. BAR thus improved healing of tracheal anastomosis.

The role of pulmonary and systemic circulation in the tracheal blood supply in rats.

The different roles of bronchial and pulmonary circulation in the tracheal blood supply were investigated in 26 female rats: a control group (CG, n = 7), a group with pulmonary hilar ligation (PL, n = 5), another with tracheal transsection (TL, n = 9) and a group with both these procedures (TL&PL, n = 5). Technetium 99-m was injected into the left ventricle postoperatively, and the radioactivity of tracheal samples was calculated as a percentage of injected activity/g tissue (%ID/g). The tracheal uptake averaged 1.9 in group CG, and 1.7, 1.3 and 1.5% ID/g in groups PL, TL and TL&PL, respectively. Tracheal transsection (TL) thus reduced the tracheal blood supply by 29.7% compared with the control group (p < 0.05), whereas the reduction of tracheal blood supply following pulmonary hilar ligation (PL) was only 10.9% (n.s.). Tracheal transsection combined with hilar ligation (TL&PL) effected a reduction of 19.9% (n.s.). We conclude that only 10.9% of the tracheal blood supply comes from the pulmonary circulation.

Airway anastomotic healing in the rat tracheal autograft.

The healing of airway anastomoses after tracheal autotransplantation was studied in a rat model. Tracheal autotransplantation in length of five tracheal cartilaginous rings was performed in 46 PVGr1 female rats. The animals were sacrificed and divided into six groups as follows: 0-day control group, and 3-, 7-, 14-, 21- and 28-day study groups (n = 6-7/group). In laser Doppler measurements, blood flow was significantly increased in the lower anastomosis after day 7 and in the upper anastomosis after day 21 compared with the control group (p < 0.05). The breaking strength of the tracheal autograft increased after day 7 compared with the control group (p < 0.05). The total collagen content of the lower anastomosis was significantly decreased on days 3 and 7 compared with the control group (p < 0.05), but thereafter it increased constantly. In the upper anastomosis on days 3 and 7, there were significant histological alterations, especially in the tracheal epithelium, compared with the control group (p < 0.05). Tracheal anastomosis is most vulnerable during the first 7 days.

Modified distal metatarsal osteotomy for hallux valgus.

Sixty-three feet in 44 patients with a hallux valgus, which had been operated on using a modified distal osteotomy were reviewed after a mean follow-up of 4.6 years. A modification of Mitchell's and Mommsen's osteotomies was used without any fixation material. The mean correction of the intermetatarsal angle was 2.6 degrees and of the hallux valgus angle 5.2 degrees. Good subjective result was achieved in 90% of the feet. In six (9.5%) cases the hallux valgus angle was worse after the operation. The method used seems to be too unreliable to be continued. Patient selection was found to be of great importance. Hallux valgus angle of more than 40 degrees was less suitable for this kind of operation.