Stephen Ho

Reduced progression of diabetic microvascular complications with islet cell transplantation compared with intensive medical therapy.

Background. The effect of islet cell transplantation (ICT) on the progression of diabetic microvascular complications is not well understood. Methods. We have conducted a prospective, crossover, cohort study comparing ICT with intensive medical therapy on the progression of diabetic nephropathy, retinopathy, and neuropathy. Results. The rate of decline in glomerular filtration rate is slower after ICT than on medical therapy. There was significantly more progression of retinopathy in medically treated patients than post-ICT. There was a nonsignificant trend for improved nerve conduction velocity post-ICT. Conclusions. ICT is associated with less progression of microvascular complications than intensive medical therapy. Multicenter, randomized trials are needed to further study the role of ICT in slowing the progression of diabetic complications.

Imaging of soft tissue infections.

Imaging of soft tissue infections has traditionally been a challenging and difficult undertaking. With the advent of cross-sectional imaging it has improved dramatically. Ultrasound, CT, and particularly MR imaging have greatly improved the ability to evaluate infectious conditions of soft tissue. This article outlines and provides examples of some of the cardinal manifestations of soft tissue infections as seen using a spectrum of different imaging modalities including plain radiography, nuclear medicine, and the cross-sectional imaging techniques mentioned previously. The soft tissue infections can be categorized in a number of different fashions. Discussed are soft tissue infections under the following headings: 1 Primary soft tissue infections: This category includes such entities as abscesses, pyomyositis, cellulitis, and other superficial infections, in particular necrotizing fasciitis 2 Soft tissue infection associated with joint infections: This includes extension of infection from septic joints and the surrounding soft tissues; septic tenosynovitis; infected bursa, either associated with joints or separate from them; and paraspinal abscesses 3 Soft tissue infections related to underlying or associated osteomyelitis 4 The diabetic foot 5 Parasitic infestations 6 Miscellaneous

Intra-abdominal free fluid without solid organ injury in blunt abdominal trauma: an indication for laparotomy.

BACKGROUND The optimal management of patients sustaining blunt abdominal trauma (BAT), in whom intra-abdominal free fluid but no solid organ injury is found on imaging, remains unclear. The purpose of this study was to determine the incidence and significance of this finding. METHODS All patients presenting with suspected BAT to a provincial trauma center over a 30-month period were reviewed. A screening focused abdominal sonogram for trauma scan was obtained in every case. Stable patients with positive or indeterminate scans underwent computed tomographic scanning. Those with free fluid but without visible solid organ injury were studied. Radiologic interpretation, clinical management, and operative findings were analyzed. RESULTS Twenty-eight of 1,367 patients (2%) met inclusion criteria. Twenty-one patients (75%) underwent exploratory laparotomy, which for 16 (76%) was therapeutic: bowel injuries were found in 10 patients, mesentery injuries in 6, and injuries to solid organs in 3. In five patients, laparotomy was nontherapeutic. Those with more than a trace of free fluid were significantly more likely to have a therapeutic procedure. Seven patients (25%) were observed, of whom two failed nonoperative management and underwent therapeutic laparotomies within 24 hours of admission for missed colon, splenic, and hepatic injuries. The presence of abdominal seat belt bruising or a Chance-type fracture in the study patients was associated with a 90% and 100% therapeutic laparotomy rate, respectively. Computed tomographic scan findings were variable and were not able to predict injury severity or need for surgery. CONCLUSION The finding of more than trace amounts of free fluid in the absence of solid organ injury in BAT is often associated with clinically significant visceral injury. Early laparotomy is recommended for these patients.

The effect of medical therapy and islet cell transplantation on diabetic nephropathy : An interim report

Background. The effect of islet cell transplantation (ICT) on renal function in type 1 diabetes is uncertain and some recent studies report a significant decline in estimated glomerular filtration rate (GFR) and worsening of albuminuria. Methods. We are conducting a prospective crossover study comparing medical treatment with islet transplantation on the progression of diabetic complications, including renal function. The primary endpoint is change in GFR measured by 99mTc-diethylenetriaminepentaacetate with secondary endpoints including estimated GFR and albumin excretion. Results. We have followed 21 patients after islet transplantation a median of 29 months (range 13–45) and compared their results with medically treated patients followed a median 29.5 months (range 13–56). There is no difference in the rate of decline in measured GFR between medically treated patients (–0.35±0.89; 95% CI: –0.57 to –0.13 mL/min/month/1.73 m2) and those after ICT (–0.31±1.18; 95% CI: –0.61 to –0.01) and neither is significantly different from that expected for the general population. The rate of decline in our estimated GFR results is lower than that reported in other studies and we did not find any worsening of albuminuria. Conclusions. We do not find evidence of worsening of renal function after islet transplantation compared with medically treated patients.

Reduced progression of diabetic retinopathy after islet cell transplantation compared with intensive medical therapy.

Background. Diabetic retinopathy is a major complication of type 1 diabetes and remains a leading cause of visual loss. There have been no comparisons of the effectiveness of intensive medical therapy and islet cell transplantation on preventing progression of diabetic retinopathy. Methods. The British Columbia islet transplant program is conducting a prospective, crossover study comparing medical therapy and islet cell transplantation on the progression of diabetic retinopathy. Progression was defined as the need for laser treatment or a one step worsening along the international disease severity scale. An interim data analysis was performed after a mean 36-month follow-up postislet transplantation and these results are presented. Results. The medical and postislet transplant groups were similar at baseline. Subjects after islet transplantation had better glucose control than the medically treated subjects (mean HbA1c 6.7%±0.9% vs. 7.5±1.2, P<0.01) and were C-peptide positive. Progression occurred significantly more often in all subjects in the medical group (10/82 eyes, 12.2%) than after islet transplantation (0/51 eyes, 0%) (P<0.01). Considering only subjects who have received transplants, progression occurred in 6/51 eyes while on medical treatment and 0/51 posttransplant (P<0.02). Conclusions. Progression of diabetic retinopathy was more likely to occur during medical therapy than after islet cell transplantation.

Imaging of Acute Small-Bowel Obstruction

OBJECTIVE The objective of this pictorial essay is to review the different imaging techniques used for diagnosing small-bowel obstruction. CONCLUSION Small-bowel obstruction is a common presentation, for which safe and effective management depends on a rapid and accurate diagnosis. Conventional radiographs remain the first line of imaging. CT is used increasingly more because it provides essential diagnostic information not apparent from radiographs. MRI may play a role in the future as technology improves and it becomes more readily available.

The DePICTORS Study: discrepancies in preliminary interpretation of CT scans between on-call residents and staff.

At many academic hospitals, radiology residents provide preliminary interpretations of CT studies performed outside of regular working hours. We examined the rate of discrepancies between resident interpretations and final reports issued by staff. We prospectively obtained 1,756 preliminary reports and corresponding final reports for computed tomography (CT) scans performed on call between November 2006 and March 2007. The overall rate of clinically significant discrepancies (those that would potentially alter the patient’s clinical course prior to issue of the final report) was 2.0%. Major discrepancy rates for abdominal/pelvic, chest, cervical spine and head CT were 4.1%, 2.5%, 1.0% and 0.7%, respectively. Senior residents had fewer major discrepancies compared to their junior colleagues. Time of interpretation was also evaluated, but a statistically significant relationship was not observed. In summary, this study demonstrates a low discrepancy rate between residents and staff radiologists and identifies areas where after-hours service may be further improved.

Multidisciplinary management of ruptured hepatocellular carcinoma

Spontaneous rupture of hepatocellular carcinoma (HCC) is a dramatic presentation of the disease. Most published studies are from Asian centers, and North American experience is limited. This study was under-taken to review the experience of ruptured HCC at a North American multidisciplinary unit. Thirty pa-tients presenting with ruptured HCC at a tertiary care center from 1985 to 2004 were studied retrospectively and analyzed according to the demographics, clinical presentation, tumor characteristics, treatment, and outcome in four treatment groups: emergency resection, delayed resection (resection after angiographic embolization), transcatheter arterial embolization (TAE), and conservative management. Ten, 10, 7, and 3 patients underwent emergency resection, delayed resection, TAE, and conservative treat-ment, respectively. The mean age of all patients was 57 years, and the mean Child-Turcotte-Pugh score was 7 ± 2. Cirrhosis was present in 57% of the patients. Seventy percent of tumors were greater than 5 cm in diameter, and 68% of patients had multiple tumors. There was a trend toward higher 30-day mortality in the emergency resection group than in the delayed resection group. One-year survival was significantly bet-ter in the delayed resection group. In selected patients, the multidisciplinary approach of angiographic em-bolization and delayed resection affords better short-term survival than emergency resection.

Recurrent Pyogenic Cholangitis: From Imaging to Intervention

OBJECTIVE The objective of this article is to familiarize the reader with the sonographic, CT, MR cholangiopancreatography, and ERCP appearances of recurrent pyogenic cholangitis and to briefly review the role of interventional radiology in the management of this disease. CONCLUSION Recurrent pyogenic cholangitis is a complex disease, the incidence of which is increasing in Western countries. Radiologists should be aware of the role of imaging in the diagnosis of this disease and the use of imaging as a guideline for subsequent intervention.

Hepatic embolotherapy in interventional oncology: technology, techniques, and applications.

Embolotherapy continues to play a growing role in the management of primary and secondary hepatic malignancies. In this review article, we examine the basis of therapy with a focus on neovascularization, which makes treatments via the hepatic artery possible. An overview of the three generations of embolic and therapeutic agents follows. The techniques, technologies, and complications of bland embolization, transarterial chemoembolization, drug-eluting beads, and selective internal radiotherapy are covered to give the reader an overview of this exciting field in interventional radiology.