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Biomechanical evaluation in osteoporosis : ovariectomized rat model

The aim of our study was to investigate the effects of ovariectomy on rat femur biomechanical parameters. Bone mineral density (BMD) and histological investigation were also evaluated. Fourteen female Sprague–Dawley rats (seven ovariectomized, seven control) were used. BMD was measured by dual-energy X-ray absorbsiometry. Bone biomechanical parameters were measured in femoral midshaft with tensile test using a biomaterial testing machine and maximum load, stiffness, energy absorption capacity (structural properties), ultimate stress, ultimate strain, and elastic modulus (material properties) were calculated. Diaphyseal cortical bone thickness was measured by using histological method. The ovariectomized (OVX) rat femur’s BMD was 14% lower than control rats (p=0.006). Mean maximum load was 55% less than the control group’s (p=0.0001). Stiffness was 72% less in OVX rats (p=0.05). Femurs of rats with OVX had 32% less absorbed energy than controls (p=0.09). From the stress–strain curve ultimate stress, ultimate strain and elastic modulus was calculated. Elastic modulus was 53% less than controls (p=0.05). Ultimate stress decreased 21% in OVX rats (p=0.097). Ultimate strain was 25% less than controls in OVX rats. Cortical thickness was significantly decreased in OVX rats than in controls (p<0.05). In conclusion, femur biomechanical parameters are decreased in osteoporosis.

HRCT evaluation of the accessory fissures of the lung

INTRODUCTION The purpose of this study was to classify the accessory fissures of the lung and to assess their frequency by using high-resolution CT. METHODS AND PATIENTS HRCT scans of 115 patients were prospectively reviewed. 1 mm thin sections were obtained at 10 mm intervals with a scan time of 1.9 s. The fissure and its relationship to the segmental bronchovascular structures were then evaluated on transverse sections. RESULTS Forty-four accessory fissures were detected in 35 of 115 patients. The most common accessory fissure was the inferior accessory fissure (12%). The second most common accessory fissure was the left minor fissure (8%). The right superior accessory fissure (5%), the accessory fissure between the medial and lateral segments of the right middle lobe (5%), and the accessory fissure between the superior and inferior segments of the lingula (5%) were seen in equal frequencies. Also, intersegmental accessory fissures, namely the fissure between the anterobasal and laterobasal of both the right (1%) and the left (2%) lower lobes were detected. We found only one subsegmental accessory fissure. DISCUSSION AND CONCLUSION The inferior accessory fissure and the left minor fissure were the most common accessory fissures in our study.

Involvement of the proximal tibiofibular joint in osteoarthritis of the knee

This study was performed to evaluate the possible involvement of the proximal tibiofibular joint in primary osteoarthritis of the knee. A total of 40 patients with primary osteoarthritis of the knee who had magnetic resonance imaging scans were reexamined for proximal tibiofibular joint involvement. The patient was questioned if pain was present in the proximal tibiofibular joint while at rest, when walking and climbing stairs. Symptoms were evaluated by applying moderate compression over the proximal tibiofibular joint during active ankle and knee motions. Magnetic resonance imaging scans were reexamined by two radiologists. Three of the 40 patients had minimal or moderate pain in the proximal tibiofibular joint during stair-climbing and on clinical examination. Magnetic resonance imaging scans of these three patients revealed osteophyte or subchondral cyst formation, or both. Degenerative changes in the proximal tibiofibular joint may be evident in association with osteoarthritis of the knee and may result in lateral-sided pain at the knee.

Diagnosis of Pediatric Varicoceles by Physical Examination and Ultrasonography and Measurement of the Testicular Volume

Introduction: The differentiation of unilateral versus bilateral varicoceles and testicular volume measurements are important in determining the need for adolescent varicocele surgery and also in following patients after varicocelectomy. The aim of this study was to prospectively compare the findings of physical examination and color Doppler ultrasonography in the diagnosis of pediatric varicoceles and to compare the findings using the Prader orchidometer and scrotal ultrasonography in the measurement of testicular volumes. Patients and Methods: This study included 68 boys with varicoceles, ranging in age from 8 to 19 years. Varicoceles were diagnosed using both physical examination and scrotal color Doppler ultrasonography. The testicular volumes of 136 testicles were measured using the Prader orchidometer and scrotal ultrasonography. A difference of more than 10% or 2 ml in each testicular volume was considered significant. Results: The mean age of the boys was 13.5 ± 2.3 years. On physical examination, a left unilateral varicocele was diagnosed in 46 boys (67.6%). The other 22 boys (32.4%) had bilateral varicoceles. Color Doppler ultrasonography detected bilateral varicoceles in 4 of the 46 boys (8.7%) who were diagnosed by physical examination as having only left unilateral varicoceles (grade 3 in 3 patients and grade 2 in 1 patient). A different of more than 10% or 2 ml in testicular volume using the Prader orchidometer versus scrotal ultrasonography was detected in 3 out of 136 testicles (2.2%). The correlation between ultrasonography and Prader orchidometer results in the measurement of testicular volumes was statistically highly significantly consistent using the intraclass correlation test (r = 0.997 and p < 0.001 for the left testis; r = 0.998 and p < 0.001 for the right testis). Conclusions: Although the management of subclinical varicoceles remains controversial, these data show that color Doppler ultrasonography may be necessary in the diagnosis of bilateral varicoceles, especially in boys with high-grade left varicoceles. In contrast, scrotal ultrasonography, if considered the gold standard, did not show superiority over the Prader orchidometer in measuring testicular volumes.

Antrolithiasis: a retrospective study.

In this retrospective study, the computed tomography (CT) archives of paranasal sinus examinations were reviewed and three cases of antroliths are presented. The archives of paranasal sinus CT studies of 1957 patients (1023 females, 934 males, mean age 36.5 years) were surveyed. CT studies were performed using 3 mm collimation and interval in the coronal, axial or both coronal and axial planes. Three out of 1957 patients demonstrated antroliths, all in the left maxillary sinus. Associated sinusitis was detected in all three patients. Only one patient was operated. The chemical analysis of the antrolith revealed it to be a calcium oxalate stone. All the relevant literature is reviewed and only 25 other cases of true antrolithiasis were encountered. The clinical and radiological features of antroliths, as well as differential diagnosis were discussed. Antrolithiasis should be considered in any case of sinusitis, that does not respond to appropriate medical therapy.

The effect of insulin therapy on biomechanical deterioration of bone in streptozotocin (STZ)-induced type 1 diabetes mellitus in rats

AIMS To investigate the effect of insulin therapy on biomechanical properties of bone in streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) in rats. METHODS A total of 28 male Wistar-Albino rats (12-week-old; 210-300g) were divided into 4 groups (n=7 for each) including control [C; no treatment], sham [Sh; distilled water i.p., for 8 weeks], diabetes [T1DM; 65mg/kg of STZ, single i.p.] and diabetes+insulin treatment [T1DM+I; 65mg/kg of STZ, single i.p.+insulin; 2-4UI/day/rat, i.p., for 8 weeks] groups. Body weight, blood glucose levels (BGLs), bone mineral density (BMD) and geometric/mechanical properties of bone tissue were evaluated. RESULTS BGLs in diabetic rats were significantly increased compared to non-diabetic rats, while the body weights were decreased (p<0.05). Femur length and cross-sectional area of femur were significantly decreased in both T1DM and T1DM+I groups (p<0.05). The significant reduction obtained in BMD in T1DM rats compared with C and Sh (p<0.05) groups was reversed by insulin treatment (p<0.05). Displacement, absorbed energy, maximum load, ultimate stress and toughness were significantly decreased inT1DM and T1DM+I groups compared to C and Sh groups (p<0.05). CONCLUSIONS In conclusion, insulin treatment seems to be ineffective in restoration of biomechanical deterioration of bone specific to STZ-induced T1DM.

Actinomycosis of the middle turbinate : an unusual cause of nasal obstruction

Actinomycosis is a rare chronic infectious disease caused by Actinomyces israelii, which is an anaerobic filamentous, gram-positive saprophyte organism of the oral cavity. Historically, these bacteria were known as fungi because of their light microscopic appearance. Actinomycosis consists of three different forms: cervico-facial (the most common form), abdominal and pulmonothoracic. It commonly involves the head and neck region including the mandible, paranasal sinuses, lacrimal gland, parotid gland and orbit. Poor oral hygiene and dental diseases have been known to be the source of actinomycosis. Actinomycosis is diagnosed with positive culture or detecting actinomyces colonies and sulfur granules in histopathologic specimens. The treatment of choice is surgical excision of the lesion and long-term penicillin therapy. Actinomycosis of the internal nose is extremely rare. There was only one nasal septum actinomycosis reported in the English literature, but there was no lateral nasal wall actiomycosis regarding the turbinate. Therefore, actinomycosis should not be overlooked for the differential diagnosis of intra-nasal lesions for the initiation of appropriate and early treatment.

Two episodes of anuria and acute pulmonary edema in a losartan-treated patient with solitary kidney.

Atherosclerotic renal artery stenosis (RAS) is an increasingly important cause of end-stage kidney disease, and may cause hypertension, progressive renal failure, and recurrent pulmonary edema. Herein, we report two episodes of anuria and acute pulmonary edema associated with losartan treatment in a hypertensive patient with preexisting severe renal artery stenosis in a solitary kidney. After successful percutaneous renal balloon angioplasty procedure, urine flow was started immediately, despite 10 days of anuria. Blood pressure measurements were still at acceptable levels with a low dose Β blocker, and serum creatinine levels were normal even after eight months. PTRA should be done in such patients, even with prolonged anuria. Physicians who recommend angiotensin receptor blockers in patients with RAS, especially in patients wih hypovolemia or a solitary kidney, should be careful about this complication.

Disseminated pneumocephalus secondary to an unusual facial trauma

Pneumocephalus can be secondary to a postintrathecal procedure, sinus fracture, basilar skull fracture, congenital skull defect, neoplasm, gas producing organism, barotrauma, neurosurgery, paranasal sinus surgery, mask or nasal continuous positive-airway pressure. Unusual facial traumas can also be rare causes of pneumocephalus. Here, we present such a case in whom an air compressor tip injury to both eyes led to the disseminated pneumocephalus. We report this rare case with the computed tomography findings and try to explain the possible mechanism of the pnemocephalus.

Primary diffuse tracheobrochial amyloidosis: case report

Respiratory amyloidosis is a rare disease that occurs in three forms: tracheobronchial, nodular parenchymal and diffuse parenchymal involment. Tracheobronchial amyloidosis is characterized by focal or diffuse deposition of amyloid in the submucosa of the trachea and proximal bronchi. Herein, we report a case of diffuse tracheobronchial amyloidosis with plain radiography and thorax computed tomography findings.