Shuji Kariya

Radiological Follow-up of New Compression Fractures Following Percutaneous Vertebroplasty

The purpose of the present study was to ascertain chronological changes in the analgesic effects of percutaneous vertebroplasty (PVP) on osteoporotic vertebral compression factures and to radiologically follow new compression fractures after PVP. Seventy-six patients (206 vertebral bodies) were followed radiologically for a mean of 11.5 months. A visual analog scale (VAS; 0–10) was used to assess pain severity, and frontal and lateral plain radiographs of the thoracic and lumbar vertebrae were taken 1–3 days and 1, 4, 10, and 22 months after PVP.The average VAS score was 7.2 ± 2.0 (mean pain score ± standard deviation) before PVP, 2.5 ± 2.3 at 1–3 days after PVP, 2.2 ± 2.3 at 1 month, 1.9 ± 2.2 at 4 months, 1.8 ± 2.4 at 10 months, and 1.0 ± 0.2 at 22 months. A new compression fracture was confirmed in 56 vertebral bodies in 28 patients (36.8%), affecting 38 adjacent vertebral bodies (67.8%), 17 nonadjacent vertebral bodies (30.4%), and 1 treated vertebral body (1.8%). A new compression fracture occurred within 1 week of PVP in 2 vertebral bodies (3.6%), between 1 week and 1 month after PVP in 22 (39.3%), between 1 and 3 months in 12 (21.4%), between 3 and 6 months in 12 (21.4%), and after more than 6 months in 8 (14.3%). PVP was highly effective in relieving the pain associated with osteoporosis-induced vertebral compression fractures, and this analgesia was long lasting. Radiological follow-up observation revealed new compression fractures in about one-third of patients. More than half of these new compression fractures occurred in adjacent vertebral bodies within 3 months of PVP.

Clinical Assessment of Percutaneous Radiofrequency Ablation for Painful Metastatic Bone Tumors

PurposeTo investigate the pain-alleviating effects of radiofrequency ablation (RFA) on metastatic bone tumors in relation to tumor size, combined therapy, and percent tumor necrosis rate following RFA.MethodsSubjects comprised 24 patients with 28 painful metastatic bone tumors. A 17G internally cooled electrode was inserted into the tumor for CT guidance and ablation was performed. Bone cement was injected following RFA for 4 tumors involving a weight-bearing bone, while 5 tumors were treated using combined RFA and external irradiation. Percent necrosis rate of the tumor was measured using contrast-enhanced computed tomography 1 week after RFA.ResultsImprovement in the visual analog scale (VAS) score was 4.6 ± 2.2 for large tumors (>5 cm, n = 12), 3.7 ± 1.8 for medium-sized tumors (3.1–5.0 cm, n = 11), and 3.5 ± 1.7 for small tumors (≤3 cm, n = 4), with no significant differences noted among tumor sizes. Improvement in the VAS score was 3.5 ± 1.3 for the 4 tumors in the RFA + bone cement group, 3.2 ± 1.9 for the 5 tumors in the RFA + radiation therapy group, and 4.8 ± 2.2 for the 18 tumors in the RFA group. No significant differences were identified between groups. The improvement in the VAS score was 3.8 ± 2.3, 4.0 ± 1.9, and 4.7 ± 2.6 in patients with tumor necrosis rates of 0–49%, 50–74%, and 75–100%, respectively. No significant association was observed among these three groups.ConclusionPercutaneous RFA therapy was effective in relieving pain due to metastatic bone tumors. No relationships appear to exist between initial response and tumor size, combined therapy, and percent tumor necrosis.

Relationship Between Cement Distribution Pattern and New Compression Fracture After Percutaneous Vertebroplasty

OBJECTIVE The objective of this study was to prospectively investigate relationships between cement distribution patterns and the occurrence rates of new compression fractures after percutaneous vertebroplasty. SUBJECTS AND METHODS Percutaneous vertebroplasty was performed for osteoporotic compression fractures in 76 consecutive patients. Patients were divided into two groups according to the cement filling pattern shown on radiography and CT: cleft pattern group (group C, n = 34), compact and solid cement filling pattern in vertebrae; and trabecular pattern group (group T, n = 42), sponge-like filling pattern. A visual analog scale (VAS) was used to assess pain severity, and anterior and lateral radiographs of the thoracic and lumbar vertebrae were obtained 1-3 days and 1, 4, 10, 22, and 34 months after percutaneous vertebroplasty. Differences in treatment efficacy and the occurrence rates of new compression fractures were examined and compared for both groups using the Mann-Whitney U test and chi-square test. RESULTS A significant difference was seen between groups with respect to the volume of cement injected per vertebra (mean volume: group C, 4.5 mL; group T, 3.7 mL; p = 0.01). VAS improvement did not differ significantly between group C (4.6) and group T (4.5). The mean follow-up period was 19.5 months, during which new compression fractures were significantly more frequent in group C (17 of 34 [50%]) than in group T (11 of 42 [26.2%]; p = 0.03). CONCLUSION Although cement distribution patterns do not significantly affect initial clinical response, a higher incidence of new compression fractures is seen in patients with treated vertebrae exhibiting a cleft pattern.

Percutaneous Vertebroplasty for Osteoporotic Compression Fractures: Long-Term Evaluation of the Technical and Clinical Outcomes

OBJECTIVE The purpose of this article is to evaluate the technical and clinical outcomes of 194 patients with 500 osteoporotic vertebral compression fractures (VCFs) consecutively treated by percutaneous vertebroplasty, to investigate the long-term efficacy of percutaneous vertebroplasty, and to determine the frequency of new VCFs after percutaneous vertebroplasty. MATERIALS AND METHODS One hundred ninety-four patients (168 women and 26 men; mean age, 73.3 years; range, 44-89 years) with 500 VCFs (T5-L5) were enrolled in this study. Evaluation at each follow-up time point (1 day, 1 month, 4 months, 1 year, and then once yearly) included pain response by using a pain visual analog scale (VAS) and frontal and lateral radiographs of the thoracic and lumbar vertebrae regardless of the symptoms. RESULTS The mean volume of cement injected was 3.3 mL (range, 0.5-12 mL) per level. Cement leakage was seen at 213 levels (42.6%). The mean follow-up time was 31 months (range, 1-97 months). The mean VAS score was 7.6 before percutaneous vertebroplasty and 3.1 at 1 day, 2.3 at 1 month, 1.7 at 4 months, 1.5 at 1 year, 1.2 at 2 years, 1.0 at 3 years, 1.1 at 4 years, 0.9 at 5 years, 0.9 at 6 years, and 1.0 at 7 years after percutaneous vertebroplasty. New VCFs were confirmed in 103 vertebrae in 65 patients (33.5%), affecting 65 adjacent vertebrae (63.1%) and 38 nonadjacent vertebrae (36.9%). CONCLUSION Percutaneous vertebroplasty was effective in relieving the pain associated with osteoporosis-induced VCFs, and the analgesic effect was long lasting when no new VCF occurred. However, radiologic follow-up observation showed that new VCFs occurred in approximately one-third of the patients.

Radiofrequency ablation combined with CO2 injection for treatment of retroperitoneal tumor: protecting surrounding organs against thermal injury.

OBJECTIVE The objective of this study was to separate target tumors from adjacent structures by injecting carbon dioxide (CO2) around the tumor to avoid thermal injury and the heat-sink effect from the blood vessel during percutaneous radiofrequency ablation. CONCLUSION We successfully achieved complete ablation of a retroperitoneal tumor without thermal injury. Imaging-guided percutaneous CO2 injection is useful for preventing thermal injury while achieving complete ablation of the tumor during radiofrequency ablation.

A case of spontaneous regression of hepatocellular carcinoma with multiple lung metastases.

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare phenomenon. We present herein the case of a patient with hepatocellular carcinoma with multiple lung metastases in whom malignancy spontaneously regressed after takingPhellinus linteus Mycelium. A 79-year-old man consulted our hospital complaining of epigastric discomfort. Abdominal MRI and CT revealed a 3 cm diameter tumor in the liver, and chest CT showed numerous nodular lesions. The levels of alpha-fetoprotein (AFP) and protein induced by vitamin K deficiency or antagonist-II (PIVKA-II) were very high. We diagnosed HCC with multiple lung metastases, and no therapy was performed. Independently he took exact fromPhellinus linteus Mycelium for one month, and 6 months later the tumors appeared to be in complete regression. The mechanism underlying this intriguing phenomenon remains unknown.

Cement Leakage in Percutaneous Vertebroplasty for Osteoporotic Compression Fractures With or Without Intravertebral Clefts

OBJECTIVE The purpose of our study was to compare the incidence and location of cement leakage in percutaneous vertebroplasty for osteoporotic compression fractures with and without intravertebral clefts. MATERIALS AND METHODS Percutaneous vertebroplasty was performed in 120 consecutive patients with 300 osteoporotic compression fractures. The cement volume injected was recorded. The cement leakage was evaluated using spinal radiography, MRI, and fluoroscopy during the procedure and CT after the procedure. RESULTS One hundred seven vertebrae contained intervertebral clefts, and 193 vertebrae had no clefts. The cement volume injected (+/- SD) was 4.0 +/- 2.0 and 3.6 +/- 1.6 mL into vertebrae with clefts and without clefts, respectively, with no statistically significant difference (p = 0.14). There was no statistically significant difference in the incidence of cement leakage between vertebrae with clefts (53 of 107) and those without clefts (78 of 193) (p = 0.13). Leakage occurred into the epidural veins (12 of 107), perivertebral soft tissues (7 of 107), disks (41 of 107), intervertebral foramen (1 of 107), and spinal canal (1 of 107) in fractures with clefts and into the epidural veins (47 of 193), perivertebral soft tissues (13 of 193), disks (25 of 193), paravertebral veins (5 of 193), large vein (2 of 193), lung (2 of 193), intervertebral foramen (1 of 193), and spinal canal (1 of 193) in fractures without clefts. Cement leakage into the epidural vein was significantly more frequent in vertebrae without clefts (p < 0.01). Disk leakage was significantly more frequent in vertebrae with clefts compared with those without clefts (p < 0.01). CONCLUSION There was no statistically significant difference in the incidence of cement leakage between vertebrae with clefts and without clefts. However, cement leakage into the epidural vein was significantly more frequent in vertebrae without clefts and disk leakage was significantly more frequent in vertebrae with clefts.

Transcatheter embolization for peripheral pseudoaneurysms with n-butyl cyanoacrylate

The purpose of this study is to evaluate the clinical efficacy of transcatheter embolization for pseudoaneurysms of peripheral arteries with n-butyl cyanoacrylate (NBCA). From November 2000 to February 2008, 17 patients with 18 pseudoaneurysms were treated by transcatheter embolization at our affiliated hospitals. The locations of the pseudoaneurysms were right hepatic artery (n=3), renal artery (n=5), splenic artery (n=2), gastroduodenal artery (n=2), common hepatic artery (n=1), pancreatic arcade (n=1), external iliac artery (n=1), internal iliac artery (n=1), internal thoracic artery (n=1), and left gastric artery (n=1). We assessed technical success rate, embolization methods, and clinical course in this study. The technical success rate was 94.4% (17/18 cases). Embolization methods were isolation (n=17) and packing (n=1). Only NBCA was used in 14 cases, both coils and NBCA were used in four cases. Six patients were in shock prior to the procedure, but all patients recovered immediately after embolization procedure including transfusion. None of the patients died of procedure-related factors or had notable postoperative complications, but three patients died within a week of the procedure because of deterioration of the underlying disease. In conclusion, transcatheter embolization of pseudoaneurysms with NBCA is a safe and effective technique for treatment.

Radiation Exposure to Operators during Vertebroplasty

PURPOSE To measure the radiation received by physicians during percutaneous vertebroplasty with use of two types of injection devices with the interventional equipment guided by computed tomography (CT) and an angiographic/CT system. MATERIALS AND METHODS Twenty consecutive patients who underwent percutaneous vertebroplasty were included in this study. The patients were divided into two groups, the 1-mL syringe group and the bone cement injector group. Percutaneous vertebroplasties were performed with the IVR-CT system, which combines angiographic and CT equipment with a single fluoroscopy table. Radiation dose to operators was measured as equivalent dose penetrating at a 10-mm tissue depth with use of electronic personal dosimeters attached outside and inside lead aprons. Effective radiation dose (HE) was estimated based on the radiation dose outside the lead apron (Ha) and the radiation dose inside the lead apron (Hb). Differences between the groups in doses and fluoroscopic duration were analyzed. RESULTS In the 1-mL syringe group and bone cement injector group, mean Ha measurements were 320.8 microSv and 116.2 microSv, respectively. Mean Hb measurements were 14.5 microSv versus 7.8 microSv and mean HE measurements were 48.2 microSv versus 19.7 microSv. Significant differences were found in Ha, Hb, and HE. However, duration of fluoroscopy did not differ significantly between groups. CONCLUSIONS Radiation dose was relatively high for operators performing percutaneous vertebroplasty. The bone cement injector was useful in reducing the level of radiation exposure to operators during vertebroplasty.

A Prospective Randomized Controlled Trial of Preoperative Whole-Liver Chemolipiodolization for Hepatocellular Carcinoma

BackgroundWe previously reported that preoperative chemolipiodolization of the whole liver is effective for reducing the incidence of postoperative recurrence and prolonging survival in patients with resectable hepatocellular carcinoma (HCC). The present randomized controlled trial was performed to evaluate the influence of preoperative transcatheter arterial chemoembolization (TACE) on survival after the resection of HCC.MethodsOperative results and long-term outcome were prospectively compared among 42 patients who received only selective TACE targeting the tumor (selective group), 39 patients who received TACE targeting the tumor plus chemolipiodolization of the whole liver (whole-liver group), and 43 patients without preoperative TACE or chemolipiodolization (control group).ResultsThere were no serious side effects of TACE or chemolipiodolization and the operative outcomes did not differ among the three groups. Even though preoperative TACE induced complete tumor necrosis, there were no significant differences in the pattern of intrahepatic recurrence or the time until recurrence among the three groups. There were also no significant differences in disease-free survival or overall survival among the three groups, even among patients with larger tumor size.ConclusionThese results indicate that preoperative selective TACE and whole-liver chemolipiodolization plus TACE do not reduce the incidence of postoperative recurrence or prolong survival in patients with resectable HCC.