Computed diffusion-weighted imaging with a low-apparent diffusion coefficient-pixel cut-off technique for breast cancer detection

OBJECTIVE

This study aimed to compare the image quality and diagnostic performance of computed diffusion-weighted imaging (DWI) with low-apparent diffusion coefficient (ADC)-pixel cut-off technique (cDWI cut-off) and actual measured DWI (mDWI).

METHODS

Eighty-seven consecutive patients with malignant breast lesions and 72 with negative breast lesions who underwent breast MRI were retrospectively evaluated. Computed DWI with high b-values of 800, 1200, and 1500 s/mm2 and ADC cut-off thresholds of none, 0, 0.3, and 0.6 (×10-3 mm2/s) were generated from DWI with two b-values (0 and 800 s/mm2). To identify the optimal conditions, two radiologists evaluated the fat suppression and lesion reduction failure using a cut-off technique. The contrast between breast cancer and glandular tissue was evaluated using region of interest analysis. Three other board-certified radiologists independently assessed the optimised cDWI cut-off and mDWI data sets. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis.

RESULTS

When an ADC cut-off threshold of 0.3 or 0.6 (× 10-3 mm2/s) was applied, fat suppression improved significantly (p < .05). The contrast of the cDWI cut-off with a b-value of 1200 or 1500 s/mm2 was better than the mDWI (p < .01). The ROC area under the curve for breast cancer detection was 0.837 for the mDWI and 0.909 for the cDWI cut-off (p < .01).

CONCLUSION

The cDWI cut-off provided better diagnostic performance than mDWI for breast cancer detection.

ADVANCES IN KNOWLEDGE

Using the low-ADC-pixel cut-off technique, computed DWI can improve diagnostic performance by increasing contrast and eliminating un-suppressed fat signals.

Impact of pain in other body regions on the foot-specific quality of life in patients with hallux valgus

OBJECTIVES

The purpose of this study was to clarify the prevalence of pain outside the foot, and to determine the associations of pain outside the foot with foot-specific quality of life (QOL) in patients with hallux valgus.

METHODS

Patients scheduled to undergo hallux valgus surgery were recruited. Patients answered whether they experienced disabling pain in 13 body regions other than the foot. Foot-specific QOLwas assessed using the Self-Administered Foot Evaluation questionnaire (SAFE-Q). Foot pain was quantified using the visual analogue scale (VAS). Patient characteristics, including age, sex, comorbidity, anxiety, and depression, were also surveyed. The association between pain elsewhere and the SAFE-Q and pain VAS scores were assessed using univariate and multivariate analyses.

RESULTS

Of 102 patients, 55 (54%) experienced pain other than the foot. All SAFE-Q subscale scores were lower, and pain VAS was higher in patients with pain elsewhere than in patients without. In the multivariate analysis, an increase in the number of pain regions was independently associated with a decrease in SAFE-Q scores and an increase in pain VAS.

CONCLUSION

More than half of the patients with hallux valgus experienced pain elsewhere. The presence of pain elsewhere was associated with poorer foot-specific QOL and severer foot pain.

Detecting lymph node metastasis of esophageal cancer on dual-energy computed tomography

Background

Using conventional computed tomography (CT), the accurate diagnosis of lymph node (LN) metastasis of esophageal cancer is difficult.

Purpose

To examine dual-energy CT parameters to predict LN metastasis preoperatively in patients with esophageal cancer.

Material and Methods

Twenty-six consecutive patients who underwent dual-energy CT before an esophageal cancer surgery (19 patients with LN metastases) were analyzed. The included LNs had a short-axis diameter of ≥4 mm and were confirmed to be resected on postoperative CT. Their short-axis diameter, CT value, iodine concentration (IC), and fat fraction were measured on early- and late-phase contrast-enhanced dual-energy CT images and compared between pathologically confirmed metastatic and non-metastatic LNs.

Results

In total, 51 LNs (34 metastatic and 17 non-metastatic) were included. In the early phase, IC and fat fraction were significantly lower in the metastatic than in the non-metastatic LNs (IC = 1.6 mg/mL vs. 2.2 mg/mL; fat fraction = 20.3% vs. 32.5%; both P < 0.05). Furthermore, in the late phase, IC and fat fraction were significantly lower in the metastatic than in the non-metastatic LNs (IC = 2.0 mg/mL vs. 3.0 mg/mL; fat fraction = 20.4% vs. 33.0%; both P < 0.05). Fat fraction exhibited accuracies of 82.4% and 78.4% on early- and late-phase images, respectively. Conversely, short-axis diameter and CT value on both early- and late-phase images were not significantly different between the metastatic and non-metastatic LNs (P > 0.05).

Conclusion

Using dual-energy CT images, IC and fat fraction are useful for diagnosing LN metastasis in patients with esophageal cancer.

Efficacy and outcomes of balloon pulmonary angioplasty in elderly vs non-elderly chronic thromboembolic pulmonary hypertension patients

Introduction

Balloon pulmonary angioplasty (BPA) has been reported as an effective and safe treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, its safety and efficacy in elderly patients remains unknown.

Purpose

We investigated the effect of BPA on hemodynamics and respiratory parameters, functional capacity, and short- and long-term outcome in elderly patients.

Methods

From November 2012 to May 2018, 141 consecutive CTEPH patients who underwent BPA in a single university hospital were enrolled (age: 65 [54.5–74] years old, WHO functional class [WHO-FC] II/III/IV; 35/96/10). Patients were divided into two groups according to the age; elderly (≥75 years, N=32) and young groups (&lt;75 years, N=109). Hemodynamics (right-sided heart catheterization), biomarkers (brain natriuretic peptide), respiratory function (spirometry and diffusion capacity measurement), and functional capacity (6-minute walk distance [6MWD] and WHO-FC) were evaluated at baseline and 1-year post BPA. Procedure-related complications (in hospital death, use of percutaneous cardiopulmonary support [PCPS], and pulmonary injury) and all cause death during the follow up period were also assessed.

Results

At baseline, although elderly group had less severe hemodynamics (mPAP: 33.1±6.7 vs 39.0±11.8 mmHg, p&lt;0.05), they had poor exercise capacity and reduced pulmonary diffusion capacity, compared with young group (6MWD: 264.6±101.3 vs 369.7±105.2 m, %DLco: 42.0±12.0 vs 50.2±12.7%, all p&lt;0.05). BPA improved hemodynamics, biomarkers, exercise capacity, and pulmonary diffusion capacity in both elderly and young groups (all p&lt;0.05). There was no in-hospital death or use of PCPS in both groups, although the incidence of pulmonary injury was higher in elderly group (14.3% vs 5.3%, p&lt;0.01). Under the normalized hemodynamics 1-year after BPA in both groups, exercise capacity and pulmonary diffusion capacity were worse in the elderly group than young groups (p&lt;0.01). The incidence of all-cause death in the follow up period was higher in elderly group, all of which were due to non-pulmonary hypertension (PH)-related death (p&lt;0.01).

Conclusion

BPA was effective in improving hemodynamics and respiratory parameters and functional capacity, in associated with no critical complication, regardless of the age. Elderly patients who were treated with BPA were associated with higher incidence of non-PH-related death.

Changes of mean PAP in the two groups

Funding Acknowledgement

Type of funding source: None

A novel causative gene variant, TNFRSF13B p.Gly76Ser, in patients with pulmonary arterial hypertension

Background

Pulmonary artery hypertension (PAH) is a poor prognostic disease. Some causative genes were reported as the PAH-associated genes. However, the pathogenetic variants in PAH-associated genes have not been identified in majority of patients with idiopathic PAH.

Purpose

Our aim was to investigate the new causative gene variants associated with PAH.

Methods

We performed whole-exome sequencing in 272 patients with idiopathic/heritable PAH. Structural analysis simulation was performed to define how the candidate gene variant affected the structure of protein.

Results

We identified the heterozygous substitution change of c.226G&gt;A (p.Gly76Ser, rs146436713) in tumor necrotic factor receptor superfamily 13B gene (TNFRSF13B) (NM_012452.2) in 6 (2.2%) patients with idiopathic/heritable PAH, although the allele frequency of this rare variant is 0% in Integrative Japanese Genome Variation Database (control population database). Two of the six cases were blood relatives, although they did not have the known causative gene variants of PAH. One of these two relatives died of right heart failure despite the combination medical therapy, and her pathological anatomy demonstrated intimal thickening and medial hypertrophy in the pulmonary arteries, formation of plexiform lesions (Heath-Edwards classification grade V). Time-lapse images from structural analysis simulation showed the instability of N-terminal in the protein, which regulates the vascular inflammation, synthesized from TNFRSF13B p.Gly76Ser variant (Figure), suggesting that p.Gly76Ser variant may be involved in the development of PAH via aberrant inflammation in pulmonary vessels.

Conclusions

TNFRSF13B p.Gly76Ser variant is a candidate of causative gene variant for PAH.

Structural analysis of proteins

Funding Acknowledgement

Type of funding source: None

De-escalation/discontinuation of oxygen-therapy and medication is feasible and safe in chronic thromboembolic pulmonary hypertension patients treated with balloon pulmonary angioplasty

Introduction

There has been increasing evidence of the efficacy of balloon pulmonary angioplasty (BPA) in improving the hemodynamics, exercise capacity, and biomarkers of patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, there is no consensus on the adjustment of home oxygen therapy (HOT) and pulmonary hypertension (PH)-specific medications after BPA in patients with CTEPH.

Purpose

We aimed to examine the current status of the de-escalation/discontinuation of HOT and PH-specific medications post-BPA, and clarify its effect on subsequent hemodynamics, biomarkers, and long-term clinical outcomes.

Methods and results

From November 2012 to July 2019, 134 consecutive CTEPH patients who underwent BPA at a single university hospital were enrolled (age; 63.6±13.4 years, female; n=87 [64.9%], WHO functional class [WHO-FC] II/III/IV; 33/92/9). Hemodynamic data, functional capacity (6-minute walk distance and WHO-FC), biomarkers (brain natriuretic peptide [BNP] and high-sensitivity troponin T [hs-TropT]), and respiratory function were evaluated at baseline, immediately and 1 year post-BPA. Clinical outcomes (all-cause death and heart failure [HF] admission) were also assessed during the follow up period. The total number of sessions was 6.3±2.0, and the number of target vessels was 14.3±2.0. Mean pulmonary arterial pressure decreased from 37.8±11.2 to 20.4±5.1 mmHg 1-year after BPA (p&lt;0.01). The proportion of patients who required HOT (at rest or on exertion) and combination medical therapy (≥2 PH-specific medications) decreased 1 year post-BPA (from 59.0% to 7.5%, and from 41.8% to 10.4%, respectively; Figure). Among 79 patients who required HOT during daytime, 64 patients (81.0%) discontinued HOT just after BPA completion. Among 56 patients who required combination medical therapy, 29 (51.8%) discontinued combination therapy. Baseline factors influencing the continuation of HOT and combination medical therapy post-BPA were almost identical (i.e. lower exercise capacity and pulmonary diffusion capacity, and worse hemodynamics). Results showed that discontinuation of HOT and combination medical therapy did not affect the maintenance of improved hemodynamics and levels of BNP and hs-TropT, and no adverse clinical outcomes (all-cause death and HF hospitalization) were observed during 1 year post-BPA.

Conclusions

Most CTEPH patients discontinued HOT and PH-specific combination medical therapy after BPA, which was not associated with the deterioration of hemodynamics, functional capacity, or biomarkers. No adverse long-term outcomes were observed. De-escalation/discontinuation of HOT and PH-specific combination medical therapy after BPA is feasible and safe for patients with CTEPH.

De-escalation of HOT and medical therapy

Funding Acknowledgement

Type of funding source: None

Prophylactic effect of rikkunshito, an herbal medicine, for chemotherapy-induced nausea in thoracic cancer patients receiving carboplatin-based chemotherapy

Rikkunshito has been shown to improve upper gastrointestinal symptoms and anorexia. The aim of this study was to evaluate whether rikkunshito improves chemotherapy-induced nausea in thoracic cancer patients receiving carboplatin (CBDCA)-based chemotherapy. A retrospective before-and-after comparison study was conducted in patients with thoracic cancer receiving the first cycle of CBDCA-based chemotherapy. Among 61 eligible patients, 34 received standard antiemetic therapy with a combination of 5-hydroxytryptamine-3 receptor antagonist and dexamethasone from September 2012 and June 2013 (standard group), while the other 27 received the standard antiemetic therapy plus oral rikkunshito from July 2013 and December 2014 (rikkunshito group). The rates of no nausea showed no significant difference between the standard and rikkunshito group (Overall phase: 64.7 % for standard group vs 74.1 % for rikkunshito group, p = 0.579). Subgroup analysis indicated that, in female patients, the rates of no nausea in rikkunshito groups was significantly higher than in standard group (overall phase: 44.4 % vs 100 %, p = 0.034). Rikkunshito did not demonstrate an additional prophylactic effect on standard antiemetic therapy for nausea in patients with thoracic cancer receiving CBDCA-based chemotherapy, but showed a prophylactic effect of nausea in female patients.

Age-dependent differences in response to partial-thickness cartilage defects in a rat model as a measure to evaluate the efficacy of interventions for cartilage repair

The objectives of this study are (1) to examine age-dependent longitudinal differences in histological responses after creation of partial-thickness articular cartilage defects (PTCDs) in rats and to use this model (2) to objectively evaluate the effectiveness of interventions for cartilage repair. Linear PTCDs were created at a depth of 100 μm in the weight-bearing region of the medial femoral condyle in rats of different ages (3 weeks, 6 weeks, 10 weeks and 14 weeks). One day, one week, two weeks, four weeks and twelve weeks after PTCD generation, spontaneous healing was evaluated histologically and immunohistochemically. Effects of interventions comprising mesenchymal stem cells (MSCs) or platelet-rich plasma (PRP) or both on 14-week-old PTCD rats were evaluated and compared with natural courses in rats of other ages. Younger rats exhibited better cartilage repair. Cartilage in 3-week-old and 6-week-old rats exhibited nearly normal restoration after 4-12 weeks. Cartilage in 14-week-old rats deteriorated over time and early signs of cartilage degeneration were observed. With injection of MCSs alone or MSCs + PRP, 14-week-old PTCD rats showed almost the same reparative cartilage as 6-week-old rats. With injection of PRP, 14-week-old PTCD rats showed almost the same reparative cartilage as 10-week-old rats. This model will be of great use to objectively compare the effects of interventions for small cartilage lesions and may help to advance the development of disease-modifying osteoarthritis drugs.

Comparative Analysis of Gene Expression between Cartilage and Menisci in Early-Phase Osteoarthritis of the Knee-An Animal Model Study

Cartilage degeneration is believed to be the primary event in the development of osteoarthritis (OA). On the other hand, meniscal degeneration is observed with high prevalence, and some researchers have pointed out that pathological changes in menisci precede that of cartilage. The purpose of the present study is to investigate comprehensive gene expression pattern of cartilage and menisci in the initial phase of surgically induced OA and to compare them. Secondary OA was surgically induced in 10-week-old male Wistar rats by anterior cruciate ligament transection (ACLT). Articular cartilage and menisci were separately dissected from six ACLT- and six sham-operated rats. Each specimen was analyzed by microarray, histological, and immunohistochemical analysis 3 weeks after surgery. Of the 36,685 transcripts detectable by microarray, the number of upregulated transcripts in ACLT menisci was >2.5-fold compared with that in ACLT menisci in any given threshold. Cluster analysis using the Database for Annotation Visualization and Integrated Discovery (DAVID) showed genes related to OA, such as response to stimulus, angiogenesis, and apoptosis, which were predominantly found in menisci in ACLT rats. Representative proteases including Adamts2, 4, Mmp2, 12, 13, 14, 16, extracellular matrix genes including versican (Vcan), lumican (Lum), syndecan1 (Sdc1), and Prostaglandin endoperoxide synthase2 (Ptgs2) were up-regulated in menisci, but were not up-regulated in cartilage. Our results indicated that the molecular changes that occurred in menisci preceded those occurred in cartilage in the very early phase of surgically induced OA models.

The recognition and incidence of peroneal tendon dislocation associated with a fracture of the talus

AIMS

The purposes of this study were to clarify first, the incidence of peroneal tendon dislocation in patients with a fracture of the talus and second the factors associated with peroneal tendon dislocation.

PATIENTS AND METHODS

We retrospectively examined 30 patients (30 ankles) with a mean age of 37.5 years, who had undergone internal fixation for a fracture of the talus. Independent examiners assessed for peroneal tendon dislocation using the pre-operative CT images. The medical records were also reviewed for the presence of peroneal tendon dislocation. The associations between the presence of dislocation with the patient characteristics or radiological findings, including age, mechanism of injury, severity of fracture, and fleck sign, were assessed using Fisher's exact tests.

RESULTS

The pre-operative CT images showed peroneal tendon dislocation in eight out of 30 patients. Dislocation was found later in one patient whose pre-operative CT image had not shown dislocation. The overall incidence of peroneal tendon dislocation was 30% (9/30). The presence of dislocation was associated with the presence of a fleck sign (p = 0.03).

CONCLUSIONS

Surprisingly, approximately one-third of the patients who underwent internal fixation for a fracture of the talus had peroneal tendon dislocation. This was associated with a fleck sign. Cite this article: Bone Joint J 2017;99-B:489-93.

Quality of Life in Patients With Untreated and Symptomatic Hallux Valgus

BACKGROUND

The purposes of this study were to compare the quality of life (QOL) of subjects who had untreated symptomatic hallux valgus with the QOL of the general population and to investigate factors associated with the QOL of the subjects.

METHODS

One hundred sixteen subjects with previously untreated and symptomatic hallux valgus were surveyed. QOL was assessed using the 36-item Short Form Health Survey (SF-36). Additionally, clinical evaluations (the visual analog scale for pain, Japanese Society for Surgery of the Foot Scale, lesser toe pain, and pain in other parts of the body) and radiographic evaluations (hallux valgus angle, intermetatarsal angle between the first and second metatarsals, and dislocation of the second metatarsophalangeal joint) were performed. Differences in the SF-36 between the subjects and the general population were tested using independent t tests. Correlations between the QOL measurements, clinical evaluations, and radiographic evaluations were assessed using Spearman rank correlation coefficient.

RESULTS

All SF-36 subscales and physical component summary scores for the subjects were significantly lower than those of the general population. Notably, the standardized physical function subscale (38.2 ± 15.8, P < .001) and physical component summary scores (38.9 ± 14.5, P < .001) were more than 10 points lower than those of the general population. Most QOL and clinical evaluation parameters were not correlated or were negligibly correlated with radiographic evaluations. Similarly, lesser toe pain or pain in other parts of the body was not correlated with QOL or clinical evaluations.

CONCLUSION

The QOL of untreated and symptomatic hallux valgus subjects was lower than that of the general population. All QOL and clinical evaluation parameters were not significantly or negligibly correlated with the severity of toe deformities. Surgical decision making should not be based on the severity of the deformity alone, but rather patient QOL should also be carefully assessed.

LEVEL OF EVIDENCE

Level III, comparative series.

Incidence and Union Rate of Avulsion Fracture at the Tip of the Fibula for Ankle Sprain in Children

Category:

Sports.

Introduction/Purpose:

Although ankle sprain in children is traditionally diagnosed as Salter-Harris type 1 epiphyseal injury because of negative radiographic findings, recent studies have reported that avulsion fracture at the tip of the fibula may be common. If the fracture remains ununited, it will become os subfibulare, and can cause pain and instability. Therefore recognition of the avulsion fracture is clinically important. However, incidence and radiographic result of the fracture is not well studied. The purposes of this study was 1)to clarify the incidence of avulsion fracture at the tip of the fibula for ankle sprain in children, 2)to assess the utility of the ATFL view proposed by Haraguchi for detection of the avulsion fracture, and 3)to clarify the union rate of the fracture.

Methods:

Patients who presented four local orthopaedic clinics were prospectively examined. Patients with a first-time inversion sprain, aged from six to twelve years, and visiting to the clinics within forty-eight hours after injury, were included. Patients underwent anteroposterior and lateral radiographs, and the ATFL view (Figure) proposed by Haraguchi at the first visit. Patients with avulsion fracture underwent follow-up radiographs 8 weeks after injury. Incidence of avulsion fracture was assessed using the radiographs at the first visit. If the fracture is visible in at least one of the three images, we diagnosed as fracture. Sensitivity of fracture detection for the standard anteroposterior and lateral view, as well as that of the ATFL view, were also evaluated. Union rate of the avulsion fracture was assessed using the radiographs at 8 weeks. The treatment was not standardized, and ranged from elastic bandage to non-weightbearing cast for 6 weeks.

Results:

From April 2014 to August 2015, 98 ankles of 98 patients (35 female and 63 male) with a mean age of 8.7 years were included. Overall incidence of avulsion fracture at the tip of the fibula was 61% (61/98 ankles). Fifty-nine avulsion fractures out of 61 were visible in the ATFL view (sensitivity, 98%), while only 28 fractures were visible in the anteroposterior and/or lateral views (sensitivity, 46%). Of the 61 ankles with fractures, 50 ankles underwent radiographs at 8 weeks. The overall union rate was 20% (10/50 ankles). When the patients received casting for 4 weeks or more, the union rate was 40%. When the patients received casting less than 4 weeks the union rate was lower, and 10%.

Conclusion:

Avulsion fracture at the tip of the fibula was surprisingly common after ankle sprain in children. More than half of the fractures were not detected in standard radiographs of the ankle, and the ATFL view should be taken routinely to detect avulsion fracture. Otherwise the fracture can be overlooked, and a misdiagnosis of Salter-Harris I injury will result. Only 20% of the fractures united after 8 weeks of injury. Although clinical significance of the avulsion fracture is yet to be determined further, the results of this study provide baseline data with which optimal treatment can be studied.

Balloon-occluded arterial stump pressure before balloon-occluded transarterial chemoembolization

OBJECTIVE

To evaluate balloon-occluded arterial stump pressure (BOASP), which is responsible for effective balloon-occluded transarterial chemoembolization (B-TACE), at each hepatic arterial level before B-TACE using a 1.8-French tip microballoon catheter for unresectable hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

The BOASP at various embolization portions was retrospectively investigated. "Selective" and "non-targeted" BOASP was defined as the BOASP at the subsegmental or segmental artery and the lobar artery, respectively.

RESULTS

The measurement of the BOASP was carried out in 87 arteries in 47 patients. BOASP > 64 mmHg was revealed in the caudate lobe artery (A1) and the left medial segmental (A4), right anterior superior segmental (A8), anterior segmental, right and left hepatic arteries. Significant difference was noted in the incidence of BOASP above 64 mmHg between "non-targeted" and "selective" BOASP (p = 0.01). "Non-targeted" BOASP was significantly greater than "selective" BOASP (p = 0.0147). In addition, the BOASP in A1, 4, 8 and the anterior segmental arteries were significantly greater than in the other subsegmental and segmental arteries (p = 0.0007).

CONCLUSION

"Non-targeted" B-TACE should be avoided to perform effective B-TACE and "selective" B-TACE at A1, 4, 8 and the anterior segmental arteries may become less effective than at the other segmental or subsegmental arteries.

Shape of the lateral edge of the first metatarsal head changes depending on the rotation and inclination of the first metatarsal: a study using digitally reconstructed radiographs

BACKGROUND

Correction of pronation deformity and metatarsal primus varus is an important component of hallux valgus surgery, necessary to achieve a satisfactory correction and to prevent post-operative recurrence. Roundness of the lateral edge of the first metatarsal head (round sign) on the dorsoplantar radiograph of the foot has been empirically advocated as an indicator of first metatarsal pronation. The purpose of this study was to clarify the effect of rotation and inclination of the first metatarsal on the shape of the lateral edge of the first metatarsal head.

METHODS

Computed tomographic images of feet in 30 subjects, without pathology of the first metatarsophalangeal joint, were included. Digitally reconstructed radiographs of the first metatarsal were created using the computed tomographic data. Thirty-nine images were created of each first metatarsal at different degrees of rotation (-10° to 30° of pronation) and inclination (-10° to 20° of plantarflexion). Then, the shape of the lateral edge of the first metatarsal head was classified into three types: angular, intermediate, and round. Generalized estimation equations were used to test if the shapes of the first metatarsal head were significantly different across the range of pronation and plantarflexion angles.

RESULTS

The positive round sign changed to negative as the first metatarsal supinated. In most feet, these changes occurred as the pronation angle decreased from 10° to 0°. The positive round sign also changed to negative as the first metatarsal head plantarflexed.

CONCLUSION

Positive round sign of the first metatarsal head on the dorsoplantar radiograph of the foot was significantly associated with increased pronation as well as decreased inclination of the first metatarsal. Negative round sign may be used as an indicator of effective correction of first metatarsal pronation during hallux valgus surgery.

Accuracy of high-resolution ultrasound in the detection of meniscal tears and determination of the visible area of menisci

BACKGROUND

Imaging is of great importance in diagnosing meniscal tears. The aim of this study was to assess the accuracy of high-resolution ultrasound in the diagnosis of meniscal tears, with arthroscopic examination as the standard reference, after resolution was confirmed with a target-mounted reference phantom. An additional goal was to elucidate the area of the meniscus that could be visualized with the same ultrasound machine after placement of markers into the menisci of cadaveric knees.

METHODS

Seventy patients were included for the assessment of the accuracy of a high-resolution ultrasound machine with a 14.0 to 6.0-MHz linear transducer. The preoperative ultrasound diagnosis, in terms of the presence and type of tear, was compared with that in the surgical reports. In the cadaveric studies, nine needles were placed in the peripheral zone of the menisci at regular intervals and the number of needles that could be observed with the system was recorded.

RESULTS

The overall sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound examination for meniscal tears were 88%, 85%, 85%, and 88%, respectively. These statistical parameters did not differ significantly between the medial and lateral menisci. The sensitivity for diagnosing horizontal, vertical, radial, flap, bucket-handle, and complex tears and for detecting discoid lateral menisci was 83%, 64%, 0%, 64%, 54%, 90%, and 80%, respectively. Ten percent of the lateral menisci could not be evaluated because of poor images. The cadaveric studies revealed that the ultrasound visualized the entire meniscus except for the anterior horn.

CONCLUSIONS

The findings of this study suggest that ultrasound examination may be suitable for screening for meniscal tears. The fact that almost 10% of the lateral menisci could not be evaluated because of poor images appears to be a weakness of ultrasound.

Hidden osteophyte formation on plain X-ray is the predictive factor for development of knee osteoarthritis after 48 months--data from the Osteoarthritis Initiative

OBJECTIVE

To examine whether the detection of osteophytes anywhere in the knee could serve as a pre-radiographic biomarker for osteoarthritis (OA) development.

METHODS

Baseline magnetic resonance imaging (MRIs) of 132 participants in the Osteoarthritis Initiative (OAI) were studied. Based on radiographs, 66 knees were assessed as osteoarthritis-free (no-osteoarthritis [NOA], or Kellgren/Lawrence [K/L] severity grade 0/1 both at baseline and 48 months), and another 66 knees were assessed as having radiographic OA changes (pre-radiographic osteoarthritis [PROA], or with K/L grade 0/1 at baseline and grade ≥ 2 at 48 months). Using baseline MRI data, we examined eight sites of osteophyte formation: the medial and lateral femoral condyle (MFC and LFC, respectively); medial and lateral tibial plateau (MTP and LTP, respectively); medial and lateral facets of the patellofemoral joint (PM and PL, respectively); tibial spine (TS); and femoral intercondylar notch (IC). Knee joint osteophyte size was assessed via the 8-point marginal osteophytes item of the whole-organ magnetic resonance imaging score (WORMS). The frequencies and distributions of osteophytes were compared between groups.

RESULTS

Mild-size osteophytes (defined as score ≥ 2) were observed more frequently at the MFC (P = 0.00278), MTP (P = 0.0046), TS (P = 0.0146), PM (P < 0.0001), PL (P = 0.0012), and IC (P < 0.0001) in PROA knees than in NOA knees. Moderate-size osteophytes (defined as score ≥ 4) were more frequently observed in PROA knees than in NOA knees only at the IC (P < 0.0001).

CONCLUSION

Knees with osteophyte formation at the IC, even those of K/L severity grade 0/1, are at risk for the development of radiographic OA by 48 months.

Transnodal lymphangiography and post-CT for protein-losing enteropathy in Noonan syndrome

Noonan syndrome, which is a multiple congenital disorder, may be associated with lymphatic abnormalities. Protein-losing enteropathy (PLE) developing in Noonan syndrome is rare. We performed transnodal lymphangiography by directly accessing bilateral inguinal nodes under ultrasound guidance in a 17-year-old female with PLE developing in Noonan syndrome to assess detailed anatomical findings regarding lymphatic vessels. There have been no reports on transnodal lymphangiography for Noonan syndrome. Post-lymphangiographic CT images revealed multiple lymphatic abnormalities and lipiodol extravasation into the duodenum and the proximal jejunum. Transnodal lymphangiography was easy and safe for PLE developing in Noonan syndrome, and post-lymphangiographic CT provided invaluable information.

Dielectric properties of fluorine substituted hydroxyapatite: the effect of the substitution on configuration of hydroxide ion chains

Dielectric properties of fluoridated hydroxyapatite (F-HAp; Ca₅(PO₄)₃(OH)_1−xF_x) were measured. The results show that the F-substitution induces the specific configuration that contains hydrogen bonds in F-HAp.

Spontaneous repair of partial thickness linear cartilage injuries in immature rats

Partial thickness articular cartilage injuries (PTCIs) were not previously thought to heal spontaneously. Immature rats have the capacity for spontaneous repair of PTCIs, although it is a long-term process. Our aim has been to examine the spontaneous repair response mechanism in immature rats. Single linear PTCIs were created in 3-week-old and 12-week-old rats in the direction of joint motion. On day 1 and at 1, 2, and 4 weeks after PTCI, evaluations of histological changes and immunohistology at the injury site and in the surrounding cartilage were performed. Anti-CD105 and anti-CD166 antibodies (as stem cell markers to identify mesenchymal stem cells in reparative cartilage tissue) were used for immunohistological evaluations. To determine whether endogenous repair ability existed in articular cartilage, an ex vivo experiment was also carried out. Femoral condyles with PTCIs were incubated in Dulbecco's modified Eagle's medium containing 10% fetal bovine serum for 1 day and for 1 and 2 weeks. Histological changes were subsequently examined. Immature cartilage showed a higher repair response than did mature cartilage, and the response occurred immediately after PTCI. In immature rats, CD105- and CD166-positive cells were found in the superficial and transitional zones of the articular cartilage. Few CD166-positive cells were identified in mature articular cartilage. No significant in vivo differences in the spontaneous repair responses to PTCIs were observed between mature and immature groups. Thus, the repair response to PTCIs seems to be associated not only with CD105- and CD166-positive cells, but also with other perichondral factors.

Tendoscopic Excision of an Intratendinous Ganglion in the Flexor Hallucis Longus Tendon: A Case Report

Intratendinous ganglion cysts are rare lesions of unknown etiology that originate within a tendon. We report the case of a 34-year-old female with an intratendinous ganglion in the plantar portion of the flexor hallucis longus tendon. The intratendinous ganglion recurred after ultrasound-guided needle aspiration. Tendoscopic excision of the intratendinous ganglion cyst achieved a satisfactorily result without recurrence.

Balloon-occluded transarterial chemoembolization using a 1.8-French tip coaxial microballoon catheter for hepatocellular carcinoma: technical and safety considerations

OBJECTIVE

To evaluate the technical feasibility and safety considerations of balloon-occluded transarterial chemoembolization (B-TACE) using a newly developed 1.8-French (Fr) tip microballoon catheter for hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

Between February 2013 and May 2013, 31 patients (20 males, 11 females; age range 56-85 years) underwent B-TACE using a 1.8-Fr tip microballoon catheter for unresectable HCC. The technical success rate, procedural complications, and adverse events of B-TACE were retrospectively investigated.

RESULTS

A total of 31 patients were subjected to 70 sessions of B-TACE using a 1.8-Fr tip microballoon catheter. The level of B-TACE was sub-subsegmental in 11, subsegmental in 35, segmental in 14, lobar in five, and right inferior phrenic artery in five sessions. The overall technical success rate was 99% (69 out of 70 sessions). As procedural complications, rupturing of the microballoon (n = 3) and aneurysmal dilatation at the site of balloon occlusion (n = 2) were encountered. There were no significant differences in any parameters between blood biochemical examination before and between two to four weeks after the procedure.

CONCLUSION

A 1.8-Fr tip microballoon catheter enables selective catheterization in patients with HCC and B-TACE using the 1.8-Fr tip microballoon catheter is a safe procedure.

Effective knock down of matrix metalloproteinase-13 by an intra-articular injection of small interfering RNA (siRNA) in a murine surgically-induced osteoarthritis model

This study investigated the effect of MMP-13 gene knock down on cartilage degradation by injecting small interfering RNA (siRNA) into knee joints in a mouse model of osteoarthritis (OA). OA was induced in male C57BL/6 mice by destabilization of medial meniscus (DMM) surgery. Change of Mmp13 expression over time was determined by qPCR analysis from 3 days to 6 weeks after surgery. Mmp13 and control chemically modified siRNA were injected into the knee joint 1 week after surgery and expression levels were assessed in synovium by qPCR 48 h later. Cartilage degradation was histologically assessed 8 weeks after DMM surgery according to OARSI recommendations. Mmp13 expression levels were elevated 1 week after surgery and peaked at 77 fold at 2 weeks compared to expression at 3 days. A 55% decrease of Mmp13 levels in cartilage was observed 48 h after injection of Mmp13 siRNA (p = 0.05). Significant reduction in the histological score at 8 weeks after surgery was observed in the Mmp13 siRNA-treated group compared to the control siRNA group (p < 0.001). Intra-articular injection of Mmp13 siRNA at the early phase of OA development resulted in effective knock down of Mmp13 expression and delay in cartilage degradation in vivo.

Preventive effects of hyaluronan from deterioration of gait parameters in surgically induced mice osteoarthritic knee model

OBJECTIVE

Osteoarthritis (OA) leads to pain and loss of function in affected joints. Gait disturbance results from these symptoms of OA, and gait analysis can be important to evaluate the progression of OA. The purpose of this study was to analyze gait pattern in a rodent model of OA and to assess the effects of intra-articular injection of hyaluronan (IAI-HA) by gait analysis, along with histological evaluation.

DESIGN

OA was induced by destabilization of the medial meniscus (DMM) of C57BL/6 mice. IAI-HA started 3 weeks after DMM surgery. Mice were allocated to three groups and were given either 800-kDa HA (800-HA), 6000-kDa HA (6000-HA) or saline. We compared these three groups with a sham group by gait analysis using CatWalk. Histological evaluation was performed to assess articular cartilage changes in the knee joints.

RESULTS

Mice injected with 800-HA or 6000-HA showed gait patterns similar to that of the sham mice, while the saline-injected group showed gait disturbances 12 and 16 weeks after DMM surgery. Histological changes in articular cartilage were similar among the 800-HA, 6000-HA and saline-treated groups, demonstrating OA progression throughout the experimental time points. Positive gait-related effects of IAI-HA might occur by its pain relieving effect and/or by preventing contracture.

CONCLUSION

IAI-HA prevented gait disturbances in the DMM model, but did not prevent histological changes associated with OA progression.

Assessment of renal shape of horseshoe kidney with multidetector row CT in adult patients: relationship between urolithiasis and renal isthmus

OBJECTIVE

The aim of this study was to evaluate the relationship between urolithiasis and characteristics of renal shape in adult patients with horseshoe kidney (HSK) diagnosed on multidetector row computed tomography (MDCT).

METHODS

We evaluated 36 patients with HSK and urolithiasis (Group A) and 70 patients with HSK without urolithiasis (Group B) whose disease was diagnosed on non-contrast MDCT. Two radiologists measured minimum width of the renal isthmus and maximum length of the renal pelvis and evaluated coexisting neoplastic diseases on axial computed tomographic (CT) images with 5-mm reconstruction, and we compared those measurements between the Groups A and B.

RESULTS

The overall mean maximum length of the renal pelvis, 12.7±9.2 mm, did not differ significantly between the 2 groups. Minimum isthmus width was larger in patients with HSK and urolithiasis (11.0±5.6 mm), than those without urolithiasis (9.5±5.1 mm). No patient in either groups had a urological renal tumor.

CONCLUSIONS

Patients of HSK might have tendency of a high incidence of stone formation. Because urolithiasis is a risk factor for tumors of the renal pelvis, monitoring of patients with HSK requires careful attention to isthmus width on CT images.

The Expansion of Paths in the Mutual Transformation Mechanism of Music and Narrative

For a mechanism of the surface expression phase in the authors' narrative generation system architecture, this paper proposes an approach to the circulative generation by the mutual transformation between music and narrative. In the concept for musical mechanism, music is not just the accompaniment for narrative and the authors extremely aim at using musical knowledge & techniques and conceptual knowledge & techniques in fusion by the medium of music. Depending on this concept, in this paper, the authosr introduce the newest prototyping system composed of eight routes of transformation modules between narrative and music including automatic composition and musical variation mechanisms. In addition, through the simple preliminary evaluations, the authors consider several insufficient points in the quality of music and the correspondence of music to narrative.

Anomalous inferior vena cava associated with horseshoe kidney on multidetector computed tomography

We evaluated the prevalence of anomalous inferior vena cava (IVC) associated with 205 patients with horseshoe kidney (HSK) and 1990 patients without HSK on multidetector computed tomography and compared prevalence between both groups. We identified anatomical variations of the IVC in 8 patients (3.9%) with HSK (1 preisthmic IVC with retrocaval ureter, 4 double IVCs, 2 left IVCs, and 1 IVC with azygos continuation) and in 12 patients (0.6%) without HSK (8 double IVCs, 3 left IVCs, and 1 IVC with azygos continuation). Anomalous IVC was significantly more frequent in patients with HSK than those without it.

Comparison of Keywords Freely Inputted by Users and the Compendium of “Keywords for Children,” Which is Programmed into the Book Searching System for Children

When children look for a book to read, they usually ask an adult to recommend something suitable. In many of such cases, librarians or teachers play an important role. It could also be parents or adults close to the children. The objective of the OPAC system provided in libraries is to offer a tool to help users to find books by themselves but it is not an easy system for children to use. In this study, we aim to construct a book searching system that is easy for children to use. To this end, we studied cases in which children used the book search engine “Adventure in the Sea of Books” we developed in 2002 for “International Institute for Children’s Literature, Osaka.” This is installed with “Subject Heading Lists for Children,” a system we uniquely developed to enable users to search a book by the title, author, or any words they can think of. In this study we will make a comparison between the keywords installed in “Subject Heading Lists for Children” and the index items which the users themselves inputted. This comparison will show what kinds of keywords are most requested by children, and lead to the development of a more userfriendly book searching system.

Antigen retrieval using sodium hydroxide for prion immunohistochemistry in bovine spongiform encephalopathy and scrapie

Formalin-fixed and paraffin wax-embedded (FFPE) tissue sections are usually used for histopathological and immunohistochemical analyses in prion diseases in animals and man. However, formalin fixation cross-links proteins, reducing disease-associated prion protein (PrP(Sc)) immunolabelling. To detect PrP(Sc) in animals naturally affected with bovine spongiform encephalopathy (BSE) and scrapie, we applied minimal pretreatment with sodium hydroxide (NaOH). This simple pretreatment, combined with enzymatic digestion using proteinase K (PK), was equally effective in the detection of PrP(Sc) in FFPE tissue, and superior in terms of speed, compared with the usual autoclaving method. The most effective results, without any section loss, were obtained with 10 μg/ml PK in phosphate buffered saline containing 0.1% Triton-X at room temperature for 10 min and 150 mM NaOH at 60 °C for 10 min. By this simple procedure, PrP(Sc) was visualized in the brain of animals with BSE and scrapie using a range of anti-PrP primary antibodies.

Visualization of azygos arch valves using computed tomography: comparison of scanning delay times

OBJECTIVE

To evaluate the frequency and appearance of azygos arch valves after short and long scanning delays and high injection rates of contrast material (CM) using a 64-slice multi-detector-row computed tomography (MDCT).

METHODS

We retrospectively reviewed the findings from 264 contrast-enhanced MDCT chest examinations. The rate of injection for 300 mg I/ml CM was 3.0 ml/sec; the short and long scanning delays were 20 and 180 sec, respectively. The presence of residual CM in the azygos arch valves and reflux of CM into the azygos arch were recorded. A chi-square test was used to compare the frequency of residual CM in azygos arch valves and reflux of CM into the azygos arch in both groups.

RESULTS

Of the 132 examinations with short scanning delays, 91 (68.9%) demonstrated residual CM in azygos arch valves and 103 (78.0%) demonstrated reflux of CM into the azygos arch. A significantly higher frequency of reflux of CM into the azygos arch and residual CM in azygos arch valves was seen with short scanning delays than with long scanning delays (P<0.05). However, no reflux of CM into azygos arch was seen with long scanning delays.

CONCLUSIONS

Both reflux of CM into azygos arch valve and residual CM in the azygos arch were frequently seen using short scanning delays.

Visualization of the azygos arch valves on multidetector-row computed tomography

To evaluate the frequency and appearance of the azygos arch valves on chest examinations using multidetector-row computed tomography (MDCT), we retrospectively reviewed findings from 194 contrast-enhanced MDCT examinations of the chest. Rate of injection of 300 mgI/ml contrast materials was low (2.0 ml/s) and high (3.0 ml/s). Scanning delay was 80 s on examination on low-rate injection of contrast material and 20 s on high-rate injection of contrast material. The presence of residual contrast material in the azygos arch valves and reflux of contrast material into the azygos arch were recorded. The Cochran-Armitage trend test was used to compare the frequency of residual contrast material in the azygos arch valves and reflux of contrast material into the azygos arch in both groups. Of 92 examinations of high-rate injection of contrast material, 63 (68.5%) demonstrated residual contrast material in the azygos arch valves and 71 (77.2%) demonstrated reflux of contrast material into the azygos arch. A significantly higher frequency of reflux of contrast material into the azygos arch and residual contrast material in the azygos arch valves was seen in the high-rate injection group than in the low-rate injection group (P < 0.05). Residual contrast material in the azygos arch valves was demonstrated more frequently when contrast material was administered in the right side of the arm than in the left side of the arm (P < 0.05). Reflux of contrast material into the azygos arch was common in the high-injection-rate group and residual contrast material in the azygos arch valves was far more frequently seen in the high-injection-rate group than in the low-injection-rate group on MDCT.

Radiological reporting that combine continuous speech recognition with error correction by transcriptionists

OBJECTIVE

We evaluated the usefulness of radiological reporting that combines continuous speech recognition (CSR) and error correction by transcriptionists.

MATERIALS AND METHODS

Four transcriptionists (two with more than 10 years' and two with less than 3 months' transcription experience) listened to the same 100 dictation files and created radiological reports using conventional transcription and a method that combined CSR with manual error correction by the transcriptionists. We compared the 2 groups using the 2 methods for accuracy and report creation time and evaluated the transcriptionists' inter-personal dependence on accuracy rate and report creation time. We used a CSR system that did not require the training of the system to recognize the user's voice.

RESULTS

We observed no significant difference in accuracy between the 2 groups and 2 methods that we tested, though transcriptionists with greater experience transcribed faster than those with less experience using conventional transcription. Using the combined method, error correction speed was not significantly different between two groups of transcriptionists with different levels of experience.

CONCLUSION

Combining CSR and manual error correction by transcriptionists enabled convenient and accurate radiological reporting.

Changes in hemodynamics and autonomic nervous activity in patients undergoing laparoscopic cholecystectomy: differences between the pneumoperitoneum and abdominal wall-lifting method

BACKGROUND AND STUDY AIMS

Intraoperative changes in circulatory hemodynamics and autonomic nervous activity were evaluated in 33 patients with cholelithiasis who underwent laparoscopic cholecystectomy.

PATIENTS AND METHODS

Of these patients, 18 were treated using a pneumoperitoneum (group G) and 15 using the abdominal wall-lifting method (group WL). Their ECG, blood pressure, arterial oxygen saturation, and expiratory carbon dioxide partial pressure were monitored. Autonomic nervous function was evaluated by spectral analysis of the heart rate.

RESULTS

Mean blood pressure increased significantly in group G during surgery, but did not vary in group WL during any stage of surgery. The high-frequency (HF) power, an index of parasympathetic activity, decreased significantly in group G after pneumoperitoneum. However, the HF power did not decrease significantly in group WL. The LF/HF ratio, an index of sympathetic activity, increased significantly in group G after pneumoperitoneum, but did not vary in group WL. In addition, the incidence of ventricular or supraventricular arrhythmias and the severity of the arrhythmias as determined by Lown's classification were higher in group G than in group WL. These findings suggest that intraoperative changes in autonomic nervous activity, due to increased intra-abdominal pressure, were smaller in patients undergoing laparoscopic cholecystectomy using the abdominal wall-lifting method than in those undergoing laparoscopic cholecystectomy using pneumoperitoneum. The results also demonstrated that hemodynamic changes were smaller in patients undergoing the abdominal wall-lifting method than in those undergoing pneumoperitoneum.

CONCLUSIONS

It was concluded that hemodynamics should be carefully monitored during pneumoperitoneum, and that the abdominal wall-lifting approach in laparoscopic cholecystectomy is a method worthy of consideration for elderly patients or those with cardiopulmonary complications.

[Theories of medicine in the newly discovered medical book "Hon'po Kagen Hishu" by San'ki Tashiro: basic prescriptions and modified prescriptions]

While investigating the formation of the Gosei-ha school in Japan by Tashiro San'ki and Manase Dosan, we discovered "Hon'po Kagen Hishu", a heretofore unknown medical book by San'ki Tashiro. A comparison of this work with Sanki's "Wakyokushu" revealed the following points. (1) "Hon'po Kagen Hishu" is a medical book compiled by San'ki Tashiro, and is believed to have been put together after the newly-compiled "Wakyokushu" (1525). (2) The book is roughly divided into two parts: basic prescriptions and modified prescriptions. "Hon'po Kagen Hishu" reveals clearly that San'ki's medical theories form the key theories of these two parts. (3) Many of the basic prescriptions contained in "Hon'po Kagen Hishu" were existing prescriptions used by the Kyokuho-ha School which was popular in Japan at the time. The modified prescriptions conform to the bian zheng pei ji (selection of drug based on the differential diagnosis) theories of the Li-Zhu medical school. (4) Among the 15 prescriptions described in the 'Shobyou Tsuyo no Yakuho' chapter of "Hon'po Kagen Hisku" secret prescriptions from schools of thought including the Nakarai school were discovered, pointing to a connection between San'ki and the Nakarai school.

[Comparative studies on saccharated preparations in traditional medicine]

We studied the descriptions of saccharated preparations found in traditional medical books and reported the following points. 1. Among the preparations described in medical books in Uigurian traditional medicine, the most numerous are saccharated preparations. These are often used to ripen and detoxicate malignant body fluids. 2. The contents of ancient writings found in Turfan in Uiguru relate not only to Greek medicine but also to Ayurvedic and Tibetan medicine. The application of saccharated preparations described in these writings is similar to that mentioned above. 3. The most important book of Tibetan medicines, "Sibu Yidian (The Four Medical Tantras)" describes saccharated preparations as making viscous body fluids ripe and improving their passage. The same book also regards them as mitigative. 4. "Caraka samnita" and "Sushruta samhita" show that honey and sugar are used separately in most cases of Ayurvedic medicine and that they expel malignant body fluids. 5. According to books of Greek medicine, honey is often added to extracts of herbal medicine at the time of taking it, and is used to ripen, detoxicate, and expel malignant body fluids. 6. The origin of saccharated preparations seems to be related to similary humoral theories in Greek, Arab, Indian, and Tibetan medicine.

[Studies of the fifth section in the introduction of the Qian jin yao fang - Writings quoted from the Shen nong ben cao jing and the Yao dui]

The fifth section in the introduction of the Qian jin yao fang is composed of three paragraphs. The first paragraph is the same as that of the Shen nong ben cao jing. The second and the third ones begin with the sentences of "Lei gong say ..." and "Yao dui says ..." respectively. We inquired into the origin of these three paragraphs. As a result of our investigation, we inferred that the first and the second paragraphs were part of the writings of the Lei gong ji zhu shen nong ben cao and that the third one was part of the Lei gong yao dui. We also pointed out that the substance of these paragraphs was influenced directly and indirectly by Buddhist medicine.

[Comparative studies of the tridosha theory in Ayurveda and the theory of the four deranged elements in Buddhist medicine]

It has been said that the tridosha theory in Ayurveda originated from the theory of the three elements of the universe. The names of these three doshas, which are roughly equivalent to humour, are vata (wind), pitta (bile), and Kapha (phlegm), corresponding to the three elements of the universe: air, fire, and water. On the other hand, Buddhist medicine which has a close relation to Ayurveda is based on the theory of the four elements of the universe which includes the earth as well as the three elements mentioned above. Greek medicine on the other hand, is founded on the theory of the four humours, i.e. blood, yellow bile, black bile, and phlegm. Furthermore, even in Ayurveda, like in "Sushruta Samhita", the theory of the four humours can be found: this includes the above-mentioned tridosha plus blood as the fourth humour. "Timaios" by Plato also mentions this. We compared these various theories and pointed out that the tridosha theory had its origin in the theory of the four elements of the universe. The process of the formation of the tridosha theory is considered as follows: (1) "Earth" was segregated from the four elements of the universe owing to its solid properties, and was rearranged into the seven elements of the body called "dhatu"; and the other three elements. "water", "fire", and "air", were integrated as the tridosha theory, namely, the theory of the three humours, owing to their properties of fluid; (2) "Blood", assigned to the element of "earth", was segregated from the tridosha because "blood" was considered to be comprised of the properties of every humour without having its own peculiar properties. Therefore, the diseases caused by deranged "blood" were regarded as an aggregate disease caused by the other three deranged humours. Then the category of the disease, caused by deranged "earth", did not appear.