Appropriate imaging utilization in Japan: a survey of accredited radiology training hospitals

Purpose

To survey whether imaging is being performed appropriately in Japan, and to survey whether radiologists intervene to ensure imaging requests are appropriate.

Methods

An online survey was sent to radiologists at accredited radiology training hospitals. The survey included the radiologists’ perspectives on whether imaging is performed appropriately at their institutions and whether they intervene if the indication for imaging is inappropriate/ambiguous.

Results

The response rate was 87.3% (165/189). We observed marked variability in the frequencies that imaging not recommended by the guidelines was performed among modalities and/or body parts; the responses “very frequently/frequently performed” were more common for breast cancer related imaging examinations and for head CT/MRI. The respondents frequently reported that inappropriate/ambiguous indications included requests to expand the craniocaudal range or to perform whole-body imaging. In 80% of the hospitals (132/165), radiologists contacted the physicians who requested unrecommended examinations; the number of CT and MRI examinations that full-time radiologists need to interpret in a half-day session was significantly smaller at these hospitals (median 18 vs 24, P = 0.032).

Conclusion

We conducted a survey to investigate appropriate imaging utilization in Japan. At the hospitals with numerous examinations to interpret, full-time radiologists may find it difficult to ensure that examinations are ordered appropriately.

     

Bortezomib induces apoptosis in T lymphoma cells and natural killer lymphoma cells independent of Epstein-Barr virus infection

Epstein-Barr virus (EBV), which infects not only B cells, but also T cells and natural killer (NK) cells, is associated with multiple lymphoid malignancies. Recently, the proteasome inhibitor bortezomib was reported to induce apoptosis of EBV-transformed B cells. We evaluated the killing effect of this proteasome inhibitor on EBV-associated T lymphoma cells and NK lymphoma cells. First, we found that bortezomib treatment decreased the viability of multiple T and NK cell lines. No significant difference was observed between EBV-positive and EBV-negative cell lines. The decreased viability in response to bortezomib treatment was abrogated by a pan-caspase inhibitor. The induction of apoptosis was confirmed by flow cytometric assessment of annexin V staining. Additionally, cleavage of caspases and polyadenosine diphosphate-ribose polymerase, increased expression of phosphorylated IκB, and decreased expression of inhibitor of apoptotic proteins were detected by immunoblotting in bortezomib-treated cell lines. We found that bortezomib induced lytic infection in EBV-positive T cell lines, although the existence of EBV did not modulate the killing effect of bortezomib. Finally, we administered bortezomib to peripheral blood mononuclear cells from five patients with EBV-associated lymphoproliferative diseases. Bortezomib had a greater killing effect on EBV-infected cells. These results indicate that bortezomib killed T or NK lymphoma cells by inducing apoptosis, regardless of the presence or absence of EBV.     

Experience of a patient with an extracorporeal ventricular assist system who participated in a sleepover program

A 19-year-old woman suffered fulminant myocarditis owing to a mycoplasma infection and was inserted with an intra-aortic balloon pump and a percutaneous cardiopulmonary support. Antibiotics and gamma globulin were administered, however, the patient’s cardiac function did not recover, and the TOYOBO ventricular assist device (VAD) was implanted. She had rehabilitation training such as maintaining a standing position at the bedside and walking in the hospital, and a hospital outing program to a family restaurant was conducted two times with the VAD. The patient wished to attend the coming-of-age ceremony in Tachikawa city, which is 3 h away from our hospital by car. Therefore, we planned the program including a night stay at her home. The patient and her family fully understood the risks and wished to participate in the sleepover program. In preparing for the sleepover, the patient and her family learned to operate the VAD, and she was able to move to the lavatory and through the house with the help of only her family. A physician and a clinical engineer stayed at her house for infusion of antibiotics and management of sudden changes. There was no adverse event. In Japan, the community support of patients with VAD is not yet established, and we hope that our experience becomes a help to support return to society for patients with VAD.     

Coronary computed tomography angiography using prospective electrocardiography-gated axial scans with 64-detector computed tomography: evaluation of stair-step artifacts and padding time

Purpose  

We compared stair-step artifacts and radiation dose between prospective electrocardiography (ECG)-gated coronary computed tomography angiography (prospective CCTA) and retrospective CCTA using 64-detector CT and determined the optimal padding time (PT) for prospective CCTA.     

Laterally spreading tumors: Limitations of computed tomography colonography

AIM: To prospectively investigate the detection rate of laterally spreading tumors (LSTs) of the colorectum by computed tomography (CT) colonography (CTC).METHODS: Patients with LSTs measuring ≥ 20 mm detected during colonoscopy were prospectively enrolled in the study. All patients underwent colonoscopy and subsequent CTC on the same day. CTC was performed using multi-detector CT without contrast in the prone and supine positions. Two radiologists blinded to the existence of LSTs read the virtual endoscopic images as well as 2-D images. LSTs were classified into granular and non-granular types based on colonoscopic appearance.RESULTS: Forty-seven pathologically proven LSTs were evaluated prospectively. Histology included adenomas in 19, mucosal cancers in 19 and T1 cancers in 9. The mean diameter of the LSTs was 35.1 mm. Twenty-eight (60%) LSTs were correctly identified by CTC, and the configuration was similar to the colonoscopic appearance in most cases. Detection rate for the granular type was significantly higher than that for the non-granular type (71% vs 31%, P = 0.013). Detection rate of adenomas was significantly lower than mucosal cancers (32% vs 79%, P = 0.008) and T1 cancers (32% vs 78%, P = 0.042).CONCLUSION: The detection rate of LSTs by CTC, particularly the non-granular type was not acceptable. Practitioners should be aware of the relatively low detection rate when using CTC.     

Preoperative evaluation of colorectal cancer using CT colonography,MRI, and PET/CT

Imaging studies are a major component in the evaluation of patients for the screening,staging and surveillance of colorectal cancer.This review presents commonly encountered findings in the diagnosis and staging of patients with colorectal cancer using computed tomography(CT)colonography,magnetic resonance imaging(MRI),and positron emission tomography(PET)/CT colonography.CT colonography provides important information for the preoperative assessment of T staging.Wall deformities are associated with muscular or subserosal invasion.Lymph node metastases from colorectal cancer often present with calcifications.CT is superior to detect calcified metastases.Three-dimensional CT to image the vascular anatomy facilitates laparoscopic surgery.T staging of rectal cancer by MRI is an established modality because MRI can diagnose rectal wall laminar structure.N staging in patients with colorectal cancer is still challenging using any imaging modality.MRI is more accurate than CT for the evaluation of liver metastases.PET/CT colonography isvaluable in the evaluation of extra-colonic and hepatic disease.PET/CT colonography is useful for obstructing colorectal cancers that cannot be traversed colonoscopically.PET/CT colonography is able to localize synchronous colon cancers proximal to the obstruction precisely.However,there is no definite evidence to support the routine clinical use of PET/CT colonography.     

Effects of mannooligosaccharides from coffee mannan on blood pressure in Dahl salt-sensitive rats

Dahl salt-sensitive (Dahl-S) rats, serving as a model of hereditary hypertension, were used to examine the effect of mannooligosaccharides (MOS) on blood pressure. Dahl-S rats were induced to develop hypertension by administering them with a 1.25% salt solution ad libitum. In a 10-wk experimental period, the Dahl-S control and MOS groups developed and maintained significantly higher blood pressure than the Dahl salt-resistant normal control group. The MOS group showed a significantly lower blood pressure than the Dahl-S control group after 5-wk of treatment (p<0.05). In addition, the serum aldosterone level of the MOS group significantly decreased (p<0.05). The findings of this study using a model of hypertensive rats suggest that MOS are able to suppress an elevation in blood pressure.     

Impact of our new protocol on the outcome of the neonates with congenital diaphragmatic hernia

Background/purpose

Congenital diaphragmatic hernia (CDH) remains a defiant challenge for pediatric surgeons. Since 2003, we developed a new protocol aiming for the better outcome. In this study, the usefulness of our new protocol was evaluated.

Materials and methods

Forty-six neonates with CDH at the age of less than 24 h were divided into two groups based on the difference of era and treatment protocols. In Group 1, 15 patients were treated between 1997 and 2002 and 31 patients were treated between 2003 and 2011 in Group 2. In the latter group, a new protocol was introduced focusing on the prevention of lung edema as well as lung injury by steroid administration and on the stabilization of cardiopulmonary function using continuous d-mannitol infusion. The survival rate and the postoperative intubation period (POIP) were compared between the two groups.

Results

The overall survival rate was significantly increased from 53 % (8/15) to 81 % (25/31) (p < 0.05). In isolated CDH, the survival rate was increased from 58 to 93 %. The average POIP was remarkably shortened from 39.0 to 4.4 days (p < 0.01).

Conclusion

Our new protocol remarkably improved the survival rate and shortened the period of mechanical ventilation in neonates with CDH.     

Influx of calcium and chloride ions into epidermal keratinocytes regulates exocytosis of epidermal lamellar bodies and skin permeability barrier homeostasis

In the nervous system, influx of calcium and chloride ions into neurons regulates the signaling system by excitation and inhibition, respectively. In this study, we demonstrated the effects of the ion influx into epidermal keratinocytes in the permeability barrier repair process of the skin after damage. Topical application of the neurotransmitters glutamate and nicotine, which activate the calcium channel in neurons, delayed the barrier repair after tape stripping. In contrast, the neurotransmitters GABA and glycine, which activate the chloride channel in neurons, accelerated barrier repair. Topical application of the calcium ionophore ionomycin delayed barrier recovery and chloride ionophore 1 accelerated barrier repair after barrier disruption by tape stripping and acetone treatment. Ionomycin increased the intracellular calcium concentration in cultured keratinocytes whereas the chloride ionophore 1 increased the intracellular chloride ion concentration. In vivo light microscopy and electron microscopy observation showed acceleration of the exocytosis of lipid-containing lamellar bodies by the chloride ionophore and delay of the exocytosis by the calcium ionophore. These results suggest that, like the nervous system, influx of calcium and chloride ions into epidermal keratinocytes through ionotropic receptors plays a crucial role in cutaneous barrier homeostasis.     

Sonographic findings of Sister Mary Joseph’s nodule from ovarian cancer

Sister Mary Joseph’s nodule (SMJN), which is known as a malignant tumor metastasized to the umbilicus, is a rare condition. We report ultrasonic findings of SMJN secondary to ovarian cancer in a 66-year-old woman. The umbilical tumor was observed as a hypoechoic mass with punctate hyperechoic foci. A pathological specimen obtained by needle biopsy confirmed adenocarcinoma with psammoma bodies. A comparison of the ultrasonographic findings with the pathological findings of the resected specimen suggested that the hyperechoic foci corresponded to psammoma bodies. When hyperechoic foci are observed inside SMJN by ultrasonography, adenocarcinoma from ovarian cancer should be included in the differential diagnosis.