Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation

A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties.     

Radiographic evaluation of the complications of long bone allografts

Purpose To study the long-term results of long bone allografts in patients with benign and malignant bone tumors.Material and Methods Forty patients for whom full clinical and radiological information was held were investigated in order to assess the overall incidence of complications including fractures, nonunion, hardware problems, infections, and bone resorption.Results There were four deaths; four more patients had distant metastases and one patient had a recurrent chondrosarcoma. Seventeen patients (42%) had either no complications (nine patients) or only minor ones (eight patients). Eleven patients (27%) sustained fractures of either their allograft (eight patients) or of their hardware (three patients). Hardware problems occurred in nine patients (22.5%), six of whom had serious problems requiring revision. The majority of the fractures and hardware problems occurred in younger male patients (82%). Infection occurred in five patients (12.5%), two of whom required revision, while two cases were superficial. Dissolution of the allograft occurred in 12 patients (30%), 7 of whom required removal of the allograft. Ten of these 12 patients were female.Conclusion The long-term survival of long bone allografts is not as good as generally reported if an adequate follow-up time period is used. Most of the fractures and hardware problems occurred in the younger active male patient, whose activities should probably be curtailed. Resorption of the allograft is another serious complication which appears to occur mainly in female patients and could possibly be controlled by chemotherapy.     

Colonic interposition: radiographic evaluation

This report reviews the clinical and radiographic features of 40 patients who underwent visceral esophageal substitution with colon for benign or malignant lesions of the esophagus. The incidence and radiographic identification of complications are discussed. All patients were routinely examined with barium esophagrams on postoperative day 10. If an anastomotic leak was suspected clinically before this time, studies were performed using water-soluble iodinated contrast material. Follow-up barium esophagrams were obtained 1-96 months after operation (average, 60 months) in 24 patients. Eight patients (21%) demonstrated asymptomatic "jejunization" of the colonic mucosa with no attributable clinical manifestations; this finding resolved in 1-3 months, without sequelae, and has not been reported before. The spectrum of ischemic changes in the colonic segment included mucosal edema, spasm, ulceration, loss of haustration, and frank necrosis. Radiographically detectable early postoperative complications included anastomotic leak in six (three pharyngocolic, three cervical esophagocolic) and aspiration of barium into the tracheobronchial tree due to incoordinated swallowing in eight. Late postoperative complications included anastomotic narrowing (12) malfunctioning of the colon due to impaired emptying (five), recurrent aspiration pneumonia (three), small bowel obstruction (three), transhiatal herniation of small bowel through the diaphragmatic hiatus (one), and reflux into the retained bypassed esophagus (one).     

Renal allografts: evaluation by MR imaging

The value of magnetic resonance (MR) imaging in assessing renal transplants was prospectively studied in 45 patients with 46 allografts. Four allografts were imaged at two different times, and separate diagnoses were given for both examinations. Therefore, this study was based on 50 proved diagnoses: nine normally functioning allografts, four allografts with acute tubular necrosis (ATN), 29 with acute rejection, one with chronic rejection, five with cyclosporin nephrotoxicity, and two with local inflammation secondary to adjacent abscess. Twenty-seven of the allografts had concomitant fluid collections. Normal renal structures with preservation of corticomedullary contrast (CMC) on T1-weighted images were demonstrated in all the normally functioning allografts. Decreased or absent CMC on T1-weighted images, reflecting a long T1 relaxation time for cortex, was found to be the most consistent sign of acute renal allograft rejection (27/29). No abnormalities on on MR images were observed in allografts compromised by cyclosporin nephrotoxicity. Hydronephrosis of the renal allograft was easily diagnosed with MR. Perirenal abscess (three cases) and perirenal hematomas (five cases), because of their higher MR signal intensity on T1-weighted images (TR = 0.5 sec, TE = 28 msec), could be differentiated from clinically insignificant postoperative fluid seromas (seven cases), lymphoceles (11 cases), and urinoma (one case).     

Desmoplastic fibroma of bone: radiographic analysis

Desmoplastic fibroma (DF) of bone is a rare, nonmetastasizing but locally aggressive tumor that has been discussed infrequently in the radiology literature. The radiographs from 107 previously published cases of DF and seven cases from the authors' institution were analyzed to better understand and define its radiographic characteristics. DF was most common in the mandible, pelvis, and femur. A geographic pattern of bone destruction, with a narrow zone of transition and nonsclerotic margins, was seen in 80 (96%) patients with intraosseous DF for whom radiographs were available (83 patients). Internal pseudotrabeculation was seen in 76 (91%). Although widening of the host bone due to gradual apposition of periosteal new bone was common, occurring in 74 (89%) patients, distinct periosteal new bone occurred in only two (2%) patients with DF of intraosseous origin. The cortex was breached in 23 (28%) patients. Three cases of DF arising in the periosteum were identified and were differentiated radiographically from desmoid tumors of intraosseous or soft-tissue origin.     

The ileoanal J pouch: radiographic evaluation

Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.     

Tarsal navicular stress fractures: radiographic evaluation

Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated.     

Dialysis access: radiographic evaluation and management

Complications related to vascular access are the most frequent cause of hospitalization for patients on chronic hemodialysis. Many complications are technical in nature and can be avoided if the original surgery is well planned and carefully performed. Radiologic evaluation plays a critical role in the diagnosis and management of failing access of almost any type.     

Neofissure after right upper lobectomy: radiographic evaluation

Following lobectomy of the right upper lobe of the lung, a single fissure, the neofissure, separates the right middle and lower lobes. In 25 patients in whom chest radiographs and computed tomographic (CT) scans were obtained after right upper lobectomy, the neofissure was identifiable to some extent on the radiographs in seven (28%) and on CT scans in 24 (96%). Among those patients in whom the neofissure was seen in its entirety, in 12 of 20 (60%) it was oriented predominantly in the coronal plane, paralleling the course of the original major fissure but displaced anteriorly and superiorly. In seven of 20 patients (35%) the superior aspect was coronal, rotated clockwise toward the sagittal plane inferiorly. In one of 20 patients (5%) the neofissure was oriented predominantly in the sagittal plane. The right middle lobe lies anterior and medial to the neofissure; the right lower lobe lies posterior and lateral.     

Artificial urinary sphincters in children: radiographic evaluation

Use of the artificial urinary sphincter to treat incontinence in children has increased over the past decade. The hydraulic fluid used in this device is radiopaque, and the radiologist is directly involved in its evaluation. Despite advances in design and surgical technique, mechanical failures and other complications occur. Our experience with 34 artificial sphincters implanted in 31 children during 1973-1983 is reviewed, giving a method of radiographic evaluation, diagnostic errors to avoid, examples of sphincter malfunction, and common complications.     

Osteoporosis: radiographic detection of fluoride-induced extra-axial bone formation

New bone formation in the peripheral skeleton was detected radiographically in 67% (22/33) of patients studied for new periarticular pain among 72 patients with osteoporosis being treated with fluoride, 66-88 mg/d, for 6 or more months. Changes included periosteal and endosteal new bone formation as well as trabecular thickening and were localized in areas of high mechanical stress. Sufficient mineral deposition for radiographic detection required 6 or more months of fluoride treatment. Radiologists must differentiate fluoride-induced new bone formation from other-processes, such as fractures and tumor, and elicit information on fluoride intake in suspicious cases.     

Tarsal navicular bone size in diabetics: radiographic assessment

Objective

To test the anecdotal observation that isolated navicular collapse is associated with diabetes mellitus, we quantified the size of the tarsal navicular bone in subjects with and without diabetes and tested for association of size with age, height, weight, body mass index (BMI), gender, smoking, bone mineral density (BMD), duration, and level of control of diabetes.

Materials and Methods

Ankle radiographs of 200 patients (122 female; 78 male; mean age 58 years [27–89]), 100 with type II diabetes and 100 age- and gender-matched controls were selected and reviewed. The anteroposterior (AP) dimension of the mid-navicular bone was measured from lateral radiographs. For standardization, the supero-inferior (SI) dimension of the calcaneal was measured and the navicular–calcaneus ratio calculated. Statistical evaluation included independent sample t tests and linear regression analyses.

Results

Diabetic subjects had a significantly smaller navicular AP dimension and navicular–calcaneus ratio compared with controls (p?=?0.02 and p?=?0.0001 respectively). Age, gender, height and duration of diabetes had no association with the navicular–calcaneus ratio. The navicular–calcaneus ratio was inversely correlated with weight (p?=?0.01) and BMI (p?<?0.001) and directly correlated with smoking (p?=?0.04). Reliability of the radiographic measurements was excellent (ICC 0.80–0.97; SEM 0.3–1.7 mm).

Conclusion

The anteroposterior dimension of the navicular is smaller in type II diabetic subjects than in age- and gender-matched controls. We hypothesize that this might be due to navicular collapse of multifactorial causes.     

Direct radiographic magnification in bone infections

An experimental model of bacterial osteomyelitis was used to investigate the correlation of direct radiographic magnification and histopathologic changes in the femora of rabbits. The histopathologic changes demonstrated a severe chronic state of osteomyelitis. The extent of radiographic changes was more clearly recognizable with direct radiological enlargement (up to 15-fold) than on normal radiographs: this applied to destruction of marrow and cortical bone, formation of sequestra, and (frequently) extraosseous extension. Histopathologic findings were in agreement with the changes revealed by direct radiographic enlargement.