[A CASE OF URACHAL CARCINOMA WITH HIGH FREQUENCY MICROSATELLITE INSTABILITY (MSI-HIGH) TREATED BY PEMBROLIZUMAB].

A 75-year-old woman was admitted to our hospital with suspected gastrointestinal perforation and underwent emergency surgery. Bladder perforation was revealed during the surgery, and she was referred to our department. We detected a tumor on the apex of the bladder and performed partial resection of the bladder. Based on histopathological examination, a diagnosis of urachal cancer was established. Gemcitabine and cisplatin (GC) therapy was administered as an adjuvant therapy because of the high risk of peritoneal dissemination. She had the purulent spondylitis and gluteus medius abscess at the first course of GC therapy. We stopped GC therapy within the first course due to the adverse events and decreased performance status. Computed tomography revealed tumor recurrence in the pelvis three months after discontinuation of GC therapy. As the companion diagnostics revealed MSI-High, we administrated pembrolizumab. She was taking prednisolone 5 mg for SLE, but stable disease was observed after 5 courses of pembrolizumab. However, pembrolizumab was discontinued for eight months due to the stent graft insertion for the common iliac artery aneurysm. She had progressive disease after eight months interval of treatment. We restarted pembrolizumab but she was hospitalized for tumor fever after a total of eight courses. The patient died a month later. This seems to be the first case wherein pembrolizumab was administered for urachal cancer with MSI-High.

Clinical Comparison of Unilateral Biportal Endoscopic Laminectomy versus Microendoscopic Laminectomy for Single-Level Laminectomy: A Single-Center, Retrospective Analysis.

BACKGROUND: The purpose of this study was to compare clinical results of microendoscopic laminectomy (MEL) with those of unilateral biportal endoscopic laminectomy (UBEL) in patients with single-level lumbar spinal canal stenosis. METHODS: The subjects consisted of 181 patients who underwent MEL (139 cases) and UBEL (42 cases) who were followed up for at least 6 months. All patients had lumber canal stenosis for 1 level. Outcomes of the patients were assessed with the duration of surgery, the bone resection area in 3-dimensional computed tomography, the facet preservation rates in computed tomography axial imagery, Visual Analog Scale (VAS) for low back pain, the Oswestry Disability Index, and the EuroQol 5-Dimensions questionnaire. RESULTS: The bone resection area in 3-dimensional computed tomography was 1.5 for MEL versus 1.0 cm2 for UBEL (P < 0.05). The facet preservation rates on the advancing side and the opposite side were 78% versus 86% (advancing side: MEL vs. UBEL) and 85% versus 94% (opposite side) (P < 0.05). The VAS (low back pain) score, VAS (leg pain), Oswestry Disability Index, and EuroQol 5-Dimension questionnaire significantly dropped in both groups at the final period (P < 0.05), however, exhibiting no difference between the 2 groups at each period. MEL resulted in greater numbers of complications, including 5 cases of hematoma paralysis, 8 cases of dura injury, 2 cases of reoperation, as opposed to zero cases of hematoma paralysis and only 2 cases of dura injury resulting from UBEL. CONCLUSIONS: The UBEL method is a more useful technique than the MEL method as it requires a smaller bone resection area and produces fewer complications.

Methylglyoxal binds to amines in honey matrix and 2'-methoxyacetophenone is released in gaseous form into the headspace on the heating of manuka honey.

Reports on the thermal stability of manuka honey in terms of food processing have been few. This study investigated changes in nine characteristic chemicals of manuka honey during heating. Among these, methylglyoxal (MGO) and 2'-methoxyacetophenone (MAP) were significantly decreased by heating at 90 °C. To elucidate the mechanism for this decrease, artificial honey was prepared from sugars and water with MAP or MGO and then heated. The decrease of MGO was enhanced with l-proline, lysine, or arginine derivatives, accompanied by formation of 2-acetyl-1-pyrroline, MGO-derived lysine dimer, or argpyrimidine, respectively, suggesting that an amino-carbonyl reaction is one pathway for the loss of MGO. The decrease of MAP in the artificial honey depended on the volume of headspace in a vessel. MAP from heated manuka honey was also detected in the gas phase, indicating that MAP was vaporized. Heating could thus reduce the beneficial and/or signature molecules in honey.

Postoperative Outcomes After Transsacral Epiduroscopic Laser Decompression in Japanese Patients: Denervation Therapy for Discogenic Low-Back Pain.

Background: Transsacral epiduroscopic laser decompression (SELD) is a very noninvasive surgery, so it is effective for elderly patients and athletes and is a new and minimally invasive therapeutic technique that may be useful in many patients with discogenic low-back pain (LBP) having high signal intensity zone (HIZ) in magnetic resonance imaging (MRI). We investigated the clinical outcomes of SELD in Japanese patients with discogenic LBP having HIZ as a first trial. Methods: The subjects consisted of 52 patients who underwent SELD and were followed up for at least 6 months. All patients with LBP with HIZ were operative using the SELD technique. Outcomes of the patients were assessed with visual analogue scale (VAS) for LBP, the Oswestry disability index (ODI), and the EuroQol 5 dimension (EQ-5D). Statistical analyses were carried out using a paired t-test. A p-value of <0.05 was considered significant. For statistical analysis, we used the SPSS software program. Results: At 12 months after the procedure, the average VAS score for LBP fell to 1.2 from 5.6 (p-value <0.05). The ODI score also dropped from the preoperative level of 22.3 to 8.8. The EQ-5D score also significantly increased from the preoperative level of 0.865 (SD 0.10) to 0.950 (SD 0.05). Eight cases of intraoperative cervical pain were observed as complications with no cases of hematomas, infections, and postoperative neurosis was observed. Conclusions: SELD provides a novel minimally invasive technique capable of performing multilevel intervertebral surgery. We believe that SELD is an effective method of treating discogenic LBP due to HIZs.

Galectin-9 expression as a poor prognostic factor in patients with renal cell carcinoma.

Recently, the effectiveness of anti-programmed death 1 (PD-1) antibody therapy in the treatment of renal cell carcinoma (RCC) has been established. Nevertheless, efficacy has been reported to be limited to only 10-30% of patients. To develop more effective immunotherapy for RCC, we analyzed the immunological characteristics in RCC tissues by immunohistochemistry (IHC). We prepared a tissue microarray that consisted of tumor tissue sections (1 mm in diameter) from 83 RCC patients in Kanagawa Cancer Center between 2006 and 2015. IHC analysis was performed with antibodies specific to immune-related (CD8 and Foxp3) and immune checkpoint (programmed death ligand 1 (PD-L1) and 2 (PD-L2), B7-H4 and galectin-9) molecules. The numbers and proportions of positively stained tumor cells or immune cells were determined in each section. From multivariate analysis of all 83 patients, higher galectin-9 expression was detected as a factor associated with worse overall survival (OS) (P = 0.029) and that higher stage and higher B7-H4 expression were associated with worse progression-free survival (PFS) (P < 0.001 and P = 0.021, respectively). Similarly, in multivariate analysis of 69 patients with clear cell RCC, though not statistically significant, there was a trend for association between higher galectin-9 expression and worse OS (P = 0.067), while higher stage was associated with worse PFS (P < 0.001). This study suggests that higher galectin-9 expression is an independent adverse prognostic factor of OS in RCC patients. Therefore, to develop more effective personalized immunotherapy to treat RCC, it may be important to target not only PD-1/PD-L1, but also other immune checkpoint molecules such as galectin-9.

A Drug-Drug Interaction Study to Evaluate the Effect of TAS-303 on CYP3A Activity in the Small Intestine and Liver.

TAS-303 (4-piperidinyl 2,2-diphenyl-2-[propoxy-1,1,2,2,3,3,3-d7 ] acetate hydrochloride) is a novel selective noradrenaline reuptake inhibitor being developed for the treatment of stress urinary incontinence. An in vitro study and a physiologically based pharmacokinetic model simulation showed that TAS-303 had inhibitory potential against cytochrome P450 (CYP) 3A. This open-label, single-group study investigated the effect of TAS-303 on CYP3A activity by evaluating the pharmacokinetics (PK) of single-dose oral simvastatin 5 mg or intravenous midazolam 1 mg after repeated oral administration of TAS-303 3 mg in 12 healthy participants. TAS-303 plus simvastatin resulted in a 1.326-fold and a 1.420-fold increase of simvastatin in peak plasma concentration and area under the plasma concentration-time curve from time zero to time t, where t is the final time of detection (AUC0-t ), respectively. The addition of midazolam resulted in a 1.090-fold increase in the midazolam AUC0-t . TAS-303 had a weak PK interaction with simvastatin but no apparent interaction with midazolam. TAS-303 at 3 mg/day is a weak inhibitor of intestinal but not hepatic CYP3A activity. No clinically important safety concerns related to TAS-303 were raised.

Estimation of internal dose from tap water after the Fukushima Daiichi Nuclear Power Station accident using newly obtained data.

Massive release of radioactive materials into the atmosphere occurred due to the Fukushima Daiichi Nuclear Power Station (FDNPS) accident in March 2011. The World Health Organization (WHO) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reported the results of dose estimation to assess the health effect of the accident and both reports state that their assessments of internal and external exposure doses contain certain uncertainties due to uncertainties inherent to the basic data. Therefore, estimation of the internal dose from tap water was conducted in this study by utilizing a database of deposition calculated by an atmospheric transfer, dispersion and deposition model (ATDM) in conjunction with the newly obtained data on the volume of daily water intake obtained by a web-based survey. The median mean and 95-percentile of thyroid equivalent doses were estimated for 1-year and 10-year children and adults in 12 municipalities in the evacuation area in Fukushima prefecture. The present mean thyroid dose estimations for 1-year children (0.4-16.2 mSv) are smaller than the corresponding values in the UNSCEAR 2013 report (1.9-49 mGy). Dose-modifying factors in the Japanese or local community are discussed.

Dynamics of the Cellular Metabolism of Leptosperin Found in Manuka Honey.

Leptosperin (methyl syringate ß-d-gentiobioside) is abundantly found in manuka honey, which is widely used because of its antibacterial and possible anti-inflammatory activities. The aim of this study was to examine the molecular mechanism underlying the metabolism of leptosperin. Five phytochemicals (leptosperin, methyl syringate (MSYR), glucuronate conjugate of MSYR (MSYR-GA), sulfonate conjugate of MSYR (MSYR-S), and syringic acid (SYR)) were separately incubated with HepG2 and Caco-2 cells. After incubation, we found that the concentration of MSYR decreased, whereas the concentrations of SYR, MSYR-GA, and MSYR-S increased. By profiling with inhibitors and carboxylesterases (CES1, 2), we found that the conversion from MSYR to SYR was mediated by CES1. Lipopolysaccharide-stimulated RAW264.7 cells restored MSYR-GA to MSYR possibly by the secreted ß-glucuronidase. All of the mice administered with leptosperin, MSYR, or manuka honey showed higher MSYR (13.84 ± 11.51, 14.29 ± 9.19, or 6.66 ± 2.30 nM) and SYR (1.85 ± 0.66, 6.01 ± 1.20, or 8.16 ± 3.10 nM) levels in the plasma compared with that of the vehicle controls (3.33 ± 1.45 (MSYR) and 1.85 ± 0.66 (SYR) nM). The findings of our study indicate that the unique metabolic pathways of these compounds may account for possible functionalities of manuka honey.

Urachal Carcinoma with Peritoneal Dissemination Treated with Chemotherapy and Surgical Resection Leading to Prolonged Survival with No Recurrence.

A 56-year-old man was admitted to our hospital for urachal carcinoma with peritoneal dissemination. He received first-line chemotherapy with gemcitabine and cisplatin. After the fifth cycle, a computed tomography (CT) scan revealed abdominal fluid, and his serum tumor marker levels were increased. The patient was started on second-line therapy with FOLFIRI. After 11 cycles, his tumor decreased in size and no new metastatic lesions were detected. The patient underwent complete tumor resection with partial cystectomy and pelvic lymph node dissection. The tumor was removed, along with adhering surrounding organs, including the omentum, peritoneum, abdominal rectus muscle, and vermiform appendix. Although pathological examination confirmed peritoneal dissemination, his tumor markers normalized soon after surgery. The patient has survived 62 months after surgery without any adjuvant therapy and with no evidence of recurrence. To our knowledge, this is the longest duration of survival without recurrence of a patient with urachal carcinoma with peritoneal dissemination who received multimodal therapy.

131I DOSE ESTIMATION FROM INTAKE OF TAP WATER IN THE EARLY PHASE AFTER FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT.

In March 2011, the Fukushima Daiichi Nuclear Power Plant Accident occurred and a large amount of radionuclides was released. To study its effect, we estimated the internal exposure due to intake of tap water in the early phase after the accident. As the number of measured values of tap water following the accident was limited, 131I concentration in tap water was estimated by 1-compartment model using the deposition amount of radionuclides calculated by an atmospheric transport, dispersion and deposition simulation. The internal doses for the evacuees were estimated by assuming representative evacuation patterns, and the internal doses for the non-evacuees were estimated for each municipal government. In the evacuation areas, the maximum of thyroid equivalent dose of 1- and 10-year-old children and adults were 22, 11 and 4.7 mSv, respectively. The maximum of thyroid equivalent dose of those three groups in the non-evacuation areas were 9.5, 4.7 and 2.0 mSv, respectively.

[RETROPERITONEAL LIPOSARCOMA WITH MULTIPLE RECURRENCE OF LUNG METASTASES TREATED BY MULTIMODAL THERAPY CENTERING ON THE OPERATION: A CASE REPORT].

A 34-year-old man presented with scrotal pain and slight fever. The scrotal pain was improved by the treatment of antibiotics, but the slight fever remained and an abdominal protuberance appeared. Computed tomography showed a 22 cm abdominal tumor with lipid density. He was then referred to our hospital. He was diagnosed as retroperitoneal liposarcoma and a surgical resection was performed for retroperitoneal tumor and surrounding organs. Histopathological diagnosis was dedifferentiated liposarcoma. 3 months after surgery, a PET/CT scan showed multiple lung metastases. We treated the patient with AI therapy by doxorubicin and ifosfamide. After 6 courses were performed, a complete response was achieved. 30months after the initial surgery, a PET/CT scan showed there was just one metastasis which was in the left lung. Thoracoscopic lung tumor resection was performed. Histopathological diagnosis was metastatic dedifferentiated liposarcoma. As adjuvant therapy, we treated with IE therapy by ifosfamide and VP-16. 3 courses were performed. 3 years and 6 months after the first surgery, he has had no recurrence up to the present day.

[A Case of Long Survival in Aggressively Growing Small Cell Carcinoma of the Bladder Successfully Treated by Combined Chemotherapy of Methotrexate, Etoposide and Cisplatin].

A 74-year-old man underwent transurethral resection for a bladder tumor (TURBT). The pathological diagnosis was urothelial carcinoma, grade 3 pT2 at least. He desired preservation of the bladder. Thus, MEC (methotrexate 100-150 mg/body (day 1), etoposide 100 mg/m2 (day 2-4), cisplatin 20 mg/m2 (day 2-6)) chemotherapy was administered for 2 courses. The next year, he had a relapse in the bladder, and the pathological diagnosiswasurothelial carcinoma, grade 2 pTa and pTis. He underwent Calmette-Guerin Bacillus (BCG) immunotherapy for 6 courses that resulted in a complete response without recurrence for 6 years. Six months after the latest examination, he complained of difficulty in voiding. An 8 cm tumor in the bladder and enlargement of obturator lymph node were detected. The pathological diagnosis by TURBT was small cell carcinoma. He rejected cystectomy, so we applied MEC therapy again. After 2 courses of MEC therapy, the bladder tumor and lymphadenopathy markedly shrunk in image and almost disappeared subsequently. The patient refused further therapy, but he had been followed without recurrence for 48 monthsafter the chemotherapy.

Surveys of Food Intake Just after the Nuclear Accident at the Fukushima Daiichi Nuclear Power Station.

As a result of the nuclear accident at the Fukushima Daiichi nuclear power station (FDNPS) after the Great East Japan Earthquake on March 11, 2011, volatile radionuclides including iodine-131 were released into the environment and contaminated open-field vegetables, raw milk, tap water, etc. It is important for the health care of residents to correctly comprehend the level of their exposure to radioactive substances released following the accident. However, an evaluation of the internal exposure doses of residents of Fukushima Prefecture as a result of the ingestion of foods, which is indicated in the report issued by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)1 is based on a number of assumptions. For instance, the estimation assumes that foods were ingested as usual, without regard to the places to which residents were evacuated after the accident, the places where food shipment restrictions were imposed, and so forth. The present report aims to improve the accuracy of estimation of the amount of food actually ingested at evacuation areas, in order to reduce as much as possible the level of uncertainty in conventional values estimated directly after the accident, which were in fact values based on conservative assumptions. More concretely, as basic source material to more accurately estimate internal exposure doses from food ingestion, various patterns of evacuation and dietary habits at the time of the accident of the residents of 13 municipalities in Fukushima Prefecture who were evacuated during the period from directly after the accident of March 11, 2011 until the end of March are clarified in this report. From survey results, most of the food that evacuees took immediately after the accident was confirmed to have been sourced from either stockpiles prepared before the accident, or relief supplies from outside of the affected areas. The restriction orders of food supplies such as contaminated vegetables and milk, and tap water intake were implemented within several days after the major release of radionuclides on March 15, 2011. In addition, collapse in supply chains, i.e., damage to distribution facilities, lack of transportation vehicles or electricity, and the closure of retail stores, contributed to a situation where food or supplies contaminated with iodine -131 were not consumed in large quantities in general, even before the food restriction order. Since people consumed tap water and water from other sources before the implementation of restriction orders in affected areas, we surveyed the status of water as a potential route of internal exposure.

[Pathological Complete Response of Metastatic Testicular Tumor with Persistent Low Level Positive Human Chorionic Gonadotropin after Chemotherapy].

We describe a case of testicular tumor with multiple metastasis to the lung,retoroperitoneal lymph node, and brain. After chemotherapy the retroperitoneal lymph node and brain metastasis disappeared,but the multiple pulmonary metastases but not disappear,although they were reduced in size. Since the human chorionic gonadotoropin (HCG) was persistently dected at a low level,we performed a testosterone tolerance test. The HCG level became undetectable for a while,but was detected at a low level again. Then the patient underwent residual tumor removal of some of the residual pulmonary disease,which was diagnosed as tumor necrosis. The patient has been followed on an ambulatory basis after surgery for 12 months without recurrence. In this case a definitive diagnosis was difficult,because of the low positive level of HCG.

[Ipsilateral Occurrence of Renal Pelvic Carcinoma after Partial Nephrectomy for Renal Cell Carcinoma].

A 70-year-old man underwent left partial nephrectomy for renal cell carcinoma (pT1aN0M0). One year after the surgery, he presented with hematuria and fatigue. Computed tomography showed a left 8 cm renal tumor and multiple liver and lung metastases. We performed percutaneous renal and liver biopsy with echo guidance. The diagnosis of both kidney and liver was urothelial carcinoma. He died 3 weeks after the diagnosis. Ipsilateral occurrence of the pelvic renal carcinoma after partial nephrectomy for renal cell carcinoma is extremely rare. To our knowledge, this case is the first to be reported in Japan and elsewhere.

[A Case of Metastatic Seminomatous Testicular Tumor with Complicated Diagnosis by FDG-PET].

18F-fluorodeoxy glucose positron emission tomography (FDG-PET) for evaluation of the post chemotherapy residual tumor of the seminomatous testicular germ cell tumor is recommended by several guidelines. We report a case whose residual tumor was evaluated by FDG PET but the results were difficult to interpret. A 41-year-old male with left seminomatous germ cell tumor of the testis and 60 mm retroperitoneal lymph node (RPLN) metastasis was referred to our hospital. The International Germ Cell Consensus Classification (IGCCC) was good prognosis. After high orchiectomy, three cycles of bleomycin, etoposide, and cisplatin (BEP) chemotherapy normalized the tumor marker and the RPLN decreased to 15 mm. The standardized uptake value (SUV) max at the RPLN by FDG-PET was 2.93. Although residual viable cells were suspected, the SUV max was relatively low. Thus surveillance without additional therapy was selected. After observation for 25 weeks, the tumor grew to 25 mm. Then four cycles of paclitaxel, ifosfamide, and cisplatin (TIP) chemotherapy were indicated for the recurrence. The RPLN was decreased to 15 mm, but the SUV max was still as high as 2.67 at 6 weeks after the last chemotherapy. We dissected the residual tumor suspecting viable cancer, but the pathological examination revealed necrotic tissue without any viable cells. He has had no signs of recurrence for 1 year and 9 months after the operation.

Development of a support tool for the clinical diagnosis of symptomatic lumbar intra- and/or extra-foraminal stenosis.

BACKGROUND: Not all lumbar intra- and/or extra-foraminal stenosis (LIEFS) on MRI is symptomatic. Therefore, the establishment of clinical diagnostic tools that can identify patients with symptomatic LIEFS is crucial in the clinical setting. The aim of this study was to develop a support tool for clinical diagnosis of LIEFS. METHODS: Patients with L5 radiculopathy alone were prospectively enrolled. Fifty-one patients with lumbar spinal canal stenosis only at the L4-5 level and 49 patients with LIEFS only at the L5-S1 level were extracted from this cohort. We compared the two groups with regard to 12 variables--three subjective and three objective items from the Japanese Orthopaedic Association (JOA) score; Kemp's sign; results of the lumbar flexion test, Bonnet test, and Freiberg test; pain on sitting; and pain when recumbent--to determine which factors were associated with a high index of clinical suspicion of LIEFS. RESULTS: The significant predictors of a final diagnosis of LIEFS were identified as follows: pain when recumbent, Freiberg and Bonnet test results, and pain on sitting. To develop a diagnostic tool, a scoring system (0-20 points) was formulated on the basis of the contribution ratios of these risk factors. To determine the contribution ratio, an integer score was assigned to the identified risk factors as follows: pain when recumbent = 9 points, Freiberg = 5 points, Bonnet = 3 points, and pain on sitting = 3 points. The Hosmer-Lemeshow statistic for this scoring system was p = 0.063, and confirmed that it was a good model. Receiver operating characteristic (ROC) curve analysis demonstrated a cut-off value of 5 points, an area under the ROC curve of 0.87435, sensitivity of 75.5 %, and specificity of 82.3 %. CONCLUSIONS: We believe that the use of this tool in the clinical setting will improve the accuracy of diagnosing symptomatic LIEFS, which will lead to improved quality of patient care.

[A case of neurogenic bladder patient whose pre-void bladder capacity was correlated with the post-void residual volume].

A 62-year-old male came to our clinic complaining of residual sensation of urine and urinary frequency. He was diagnosed with neurogenic bladder, and has been performing clean intermittent self catheterization once or twice a day. According to his urination record of voided volume (VV) and post-void residual urine volume (PVR) on every urination, we investigated the relationship between pre-void bladder capacity (BC) and PVR. BC was expressed as the sum of VV and PVR. The PVR of BC 300-400, 400-500, 500-600 and ≧600 ml was 141.1, 167.7, 186.8 and 193.3 ml, respectively. PVR significantly increased as BC increased (p＜0.01). Although there are few reports about the relationship between BC and PVR, the present results show that bladder over distension may reduce the contractility of the urinary bladder.

[Additional administration of dutasteride in patients with benign prostatic hyperplasia who did not respond sufficiently to α1-adrenoceptor antagonist : investigation of clinical factors affecting the therapeutic effect of dutasteride].

We performed additional administration of dutasteride in patients who did not respond sufficiently to α1-adrenoceptor antagonist treatment for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) (LUTS/BPH). Among 76 registered patients, efficacy was analyzed in 58 patients. International Prostate Symptom Score (IPSS), subscores for voiding and storage symptoms and quality of life (QOL) on the IPSS, and Overactive Bladder Symptom Score (OABSS) were all significantly improved from the third month of administration compared to the time of initiating additional administration of dutasteride. Additional administration of dutasteride also significantly reduced prostate volume, and residual urine with the exception of the sixth month after administration. Age at initiation of administration and voiding symptom subscore on the IPSS were clinical factors affecting the therapeutic effects of dutasteride. The rate of improvement with treatment decreased with increasing age at initiation of dutasteride administration, and increased as voiding symptom subscore on the IPSS increased. Therefore, additional administration of dutasteride appears useful for cases of LUTS/BPH in which a sufficient response is not achieved with α1-adrenoceptor antagonist treatment. Because patients who have severe voiding symptoms or begin dutasteride at an early age may be expected to respond particularly well to dutasteride in terms of clinical efficacy, they were considered to be suitable targets for additional administration.

A new electrophysiological method for the diagnosis of extraforaminal stenosis at L5-s1.

STUDY DESIGN: A retrospective study. PURPOSE: To examine the effectiveness of using an electrodiagnostic technique as a new approach in the clinical diagnosis of extraforaminal stenosis at L5-S1. OVERVIEW OF LITERATURE: We introduced a new effective approach to the diagnosis of extraforaminal stenosis at the lumbosacral junction using the existing electrophysiological evaluation technique. METHODS: A consecutive series of 124 patients with fifth lumbar radiculopathy were enrolled, comprising a group of 74 patients with spinal canal stenosis and a second group of 50 patients with extraforaminal stenosis at L5-S1. The technique involved inserting a pair of needle electrodes into the foraminal exit zone of the fifth lumbar spinal nerves, which were used to provide electrical stimulation. The compound muscle action potentials from each of the tibialis anterior muscles were recorded. RESULTS: The distal motor latency (DML) of the potentials ranged from 11.2 to 24.6 milliseconds in patients with extraforaminal stenosis. In contrast, the DML in patients with spinal canal stenosis ranged from 10.0 to 17.2 milliseconds. After comparing the DML of each of the 2 groups and at the same time comparing the differences in DML between the affected and unaffected side of each patient, we concluded there were statistically significant differences (p<0.01) between the 2 groups. Using receiver operating characteristic curve analysis, the cutoff values were calculated to be 15.2 milliseconds and 1.1 milliseconds, respectively. CONCLUSIONS: This approach using a means of DML measurement enables us to identify and localize lesions, which offers an advantage in diagnosing extraforaminal stenosis at L5-S1.