The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management

AIMS

To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management.

MATERIALS AND METHODS

Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months.

RESULTS

In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative.

CONCLUSIONS

Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes.

Pulmonary cement embolism: a complication of percutaneous vertebroplasty

BACKGROUND

Percutaneous vertebroplasty (PV) has recently become a very common procedure for vertebral compression fractures. Extravasation of cement, a common event associated with vertebroplasty, may lead to cement emboli in the lungs.

PURPOSE

To determine the frequency of pulmonary cement embolism after percutaneous vertebroplasty.

MATERIAL AND METHODS

Between 2002 and 2006, 128 percutaneous vertebroplasties were performed in 73 patients (56 women and 17 men) in our institution. Postprocedural chest radiographs were obtained for all patients and assessed for the presence of pulmonary cement emboli.

RESULTS

Pulmonary cement embolism was detected on chest radiographs and confirmed with chest computed tomography (CT) in four patients treated with percutaneous vertebroplasty for osteoporotic collapse and one patient treated for multiple myeloma. The imaging finding of pulmonary cement embolism was solitary or multiple fine radiodense lines with occasional branching patterns. The frequency of pulmonary cement embolism was 6.8%.

CONCLUSION

An incidence of pulmonary cement embolism of 6.8% during PV was found. Close clinical follow-up, postprocedural chest radiographs, and chest CT scans, if necessary, are important for the detection of pulmonary cement embolism at an early stage.

Delayed onset bleomycin-induced pneumonitis

We describe a 39-year-old male patient who developed bleomycin-induced pneumonitis 2 years after completion of chemotherapy for nonseminomatous testicular cancer. Bleomycin sometimes causes fatal pulmonary toxicity, including bleomycin-induced pneumonitis. The central event in the development of pneumonitis is endothelial damage of the lung vasculature due to bleomycin-induced cytokines and free radicals. Pulmonary toxicity usually begins at bleomycin administration. The development of bleomycin-induced pneumonitis up to 6 months after bleomycin therapy has also been reported. We report a patient who developed bleomycin-induced pneumonitis 2 years after the initiation of bleomycin-containing chemotherapy regimens.

A combination of small bowel imaging methods: conventional enteroclysis with complementary magnetic resonance enteroclysis

AIM

The aim of this prospective study was to evaluate the overall findings of conventional enteroclysis (CE) with complementary magnetic resonance enteroclysis (MRE) in small bowel disease.

METHODS

The study included 32 patients referred from various clinical departments, with known or suspected small bowel disease and abnormalities on CE. Immediately after CE, true fast imaging with steady-state precession (true FISP), and unenhanced and gadolinium-enhanced T1-weighted fast low-angle shot (FLASH) sequences with fat saturation were obtained. Mucosal, mural and luminal changes of the small bowel were evaluated by each technique. In addition, bowel wall thickening, bowel wall enhancement and perienteric changes were assessed by MRE. The radiological findings obtained were evaluated together as a combination, and the role of MRE in the determination of the activity and complications of the small bowel disease was assessed. Radiological findings were correlated with clinical evaluation and follow-up in all cases, including endoscopy in 14 cases and surgery in 5 cases.

RESULTS

MRE provided important supplementary mural and extramural information, including degree of pathological wall thickness, mural enhancement pattern associated with disease activity, perivisceral collection, abscess formation, mesenteric fibrofatty proliferation, lymphadenopathy and increase in perienteric vascularity. Short strictures were not revealed on MRE; however, for patients with a history of abdominal malignancy, MRE helped characterize the level of any obstruction and the extent of the disease.

CONCLUSION

We recommend MRE for patients who have findings of advanced inflammatory bowel disease or neoplasm on CE examination. The combination of these two techniques can provide important information on the degree and extent of the disorder.

Imaging in mediastinitis: a systematic review based on aetiology

Mediastinitis refers to inflammation of the tissues located in the middle chest cavity. It can be secondary to infectious or non-infectious causes and depending on the aetiology may be acute or chronic. The majority of cases of acute mediastinitis are secondary to oesophageal perforation and open chest surgery. Less common causes include tracheal, bronchial perforation or direct extension of infection from adjacent tissues. Chronic or slowly developing mediastinitis mostly arise from tuberculosis, histoplasmosis, other fungal infections, cancer, or sarcoidosis. In a minority of cases the aetiology is lymphatic obstruction or an autoimmune disease. Radiological imaging plays an essential role in the diagnosis and therapeutic approach to mediastinitis. Generally, the initial radiological work-up includes radiographic studies either with or without contrast material. However, conventional chest radiography may be misleading in the diagnosis of mediastinitis. Cross-sectional imaging techniques are generally required for diagnosis and evaluation of the site and extent of mediastinal involvement. Computed tomography and magnetic resonance imaging may also guide the choice of the optimal therapeutic approach.

Beneficial effects of enriched environment following status epilepticus in immature rats

BACKGROUND

There is increasing evidence that enriching the environment can improve cognitive and motor deficits following a variety of brain injuries. Whether environmental enrichment can improve cognitive impairment following status epilepticus (SE) is not known.

OBJECTIVE

To determine whether the environment in which animals are raised influences cognitive function in normal rats and rats subjected to SE.

METHODS

Rats (n = 100) underwent lithium-pilocarpine-induced SE at postnatal (P) day 20 and were then placed in either an enriched environment consisting of a large play area with toys, climbing objects, and music, or in standard vivarium cages for 30 days. Control rats (n = 32) were handled similarly to the SE rats but received saline injections instead of lithium-pilocarpine. Rats were then tested in the water maze, a measure of visual-spatial memory. A subset of the rats were killed during exposure to the enriched or nonenriched environment and the brains examined for dentate granule cell neurogenesis using bromodeoxyuridine (BrdU) and phosphorylated cyclic AMP response element binding protein (pCREB) immunostaining, a brain transcription factor important in long-term memory.

RESULTS

Both control and SE rats exposed to the enriched environment performed significantly better than the nonenriched group in the water maze. There was a significant increase in neurogenesis and pCREB immunostaining in the dentate gyrus in both control and SE animals exposed to the enriched environment compared to the nonenriched groups. Environmental enrichment resulted in no change in SE-induced histologic damage.

CONCLUSIONS

Exposure to an enriched environment in weanling rats significantly improves visual-spatial learning. Even following SE, an enriched environment enhances cognitive function. An increase in neurogenesis and activation of transcription factors may contribute to this enhanced visual-spatial memory.

Cerebellar astrocytoma presenting with acute esotropia in a 5 year-old girl. Case report

We encountered a 5-year-old girl with acute onset of alternating, comitant esotropia in the absence of diplopia and other neurologic findings. She did not have any refractive error and seen bilateral papilledemas in fundus examination, magnetic resonance imaging (MRI) of the head was performed. A large cerebellar astrocytoma and moderate hydrocephalus was identified and successfully resected. The onset of comitant esotropia in a child can be the first sign of a cerebellar tumor without any other neurologic signs and symptoms.

Spontaneous pneumothorax: a rare complication of miliary tuberculosis

Pneumothorax is a rare complication of miliary tuberculosis. In this report, a 25-year old patient developing pneumothorax while on the treatment for miliary tuberculosis treatment is presented and the related literature has been reviewed. Pneumothorax, although rare, should be considered when a patient with miliary tuberculosis develops a sudden, severe pain on either side of the chest with breathlessness. The treatment should be tailored according to the size of pneumothorax either pleural drainage through chest tube or needle aspiration. Meanwhile, antituberculous treatment should be continued without interruption.

CNS involvement in neuro-Behçet syndrome: an MR study

BACKGROUND AND PURPOSE

Behçet disease (BD) is a multisystem vasculitis of unknown origin in which neurologic involvement has been reported in the range of 5% to 10% in large series. Reports on clinical and radiologic aspects of neuro-Behçet syndrome (NBS) are in general limited in number. Our purpose was to determine the MR patterns in patients with NBS who had neural parenchymal involvement and to correlate our findings with possible vascular pathophysiology.

METHODS

The MR images of 65 patients with NBS and neural parenchymal involvement were reviewed. In a subgroup of patients who had serial MR studies, we evaluated the anatomic-radiologic location and distribution of the lesions and whether they corresponded to any vascular territory, and studied their extension, enhancement patterns, and temporal course.

RESULTS

The most common imaging finding in NBS patients who had neural parenchymal involvement was a mesodiencephalic junction lesion with edema extending along certain long tracts in the brain stem and diencephalon in 46% of the patients. The next most common location of involvement was the pontobulbar region, seen in 40% of the cases. Three primary cervical spinal cord lesions and one case of isolated optic nerve involvement were observed.

CONCLUSION

The parenchymal distribution of lesions in NBS appears to support the hypothesis of small-vessel vasculitis; mainly, venular involvement. The anatomic distribution of intraaxial veins of the CNS explains the predominant involvement of the brain stem structures observed in our patients. This pattern of lesion distribution might help to differentiate NBS from other vasculitides as well as from the inflammatory-demyelinating diseases of the CNS, such as multiple sclerosis.

Ovarian stromal hypertrophy in polycystic ovary syndrome

OBJECTIVE

To investigate the relationship between the ovarian stromal area and clinical hormonal characteristics in women with polycystic ovary syndrome (PCOS).

STUDY DESIGN

Twenty-eight women with PCOS (group 1) and 26 healthy women (group 2) participated in this study. For measuring the ovarian stromal area, transvaginal ultrasonography was performed on all women during the early follicular phase of the menstrual cycle. Venous blood was sampled from the women to determine serum follicle stimulating hormone, luteinizing hormone (LH), estradiol, androstenedione, free testosterone (FT), total testosterone (TT), 17 alpha-hydroxyprogesterone, dehydroepiandrosterone sulfate, and fasting insulin and glucose levels. Two-tailed t and Pearson correlation tests were used for statistical analysis.

RESULTS

Women with PCOS were heavier, and their serum FT, TT and LH levels were significantly higher than in the normals (P < .001, P < .012 and P < .001, respectively). The ovarian stromal area measured by transvaginal ultrasonography was also significantly larger than in the normals (P < .001). Only basal serum insulin levels seemed to correlate positively with the ovarian stromal area in women with PCOS (r = .43 P = .09).

CONCLUSION

Although transvaginal ultrasonography has played an important role in the evaluation of women with PCOS, we could not demonstrate a relationship between the ovarian stromal area and hormonal characteristics of PCOS. Therefore, transvaginal ultrasonography and hormonal parameters must be used as complementary diagnostic methods in women with PCOS.

Mammographic changes in women receiving tibolone therapy

OBJECTIVE

To investigate the effects of tibolone therapy for menopausal symptoms on mammographic findings and to identify any association between mammographic changes and the demographic and hormonal characteristics of women receiving tibolone.

DESIGN

A prospective study.

SETTING

A university hospital.

PATIENT(S)

Seventy-five women who were in the climacteric or postmenopausal period were recruited, and 25 of them were followed up for 24 months.

INTERVENTION(S)

After high-resolution mammographies were performed and blood samples were collected, tibolone (2.5 mg/d) was administered orally to all patients. At the end of the 24-month follow-up period, blood samples were collected again and mammographies were repeated.

MAIN OUTCOME MEASURE(S)

Serum levels of LH, FSH, prolactin, estradiol, testosterone, and DHEAS were determined from the collected samples, and mammographies were interpreted.

RESULT(S)

At the end of the 24-month follow-up period, mammographic changes were observed in only two women (8%). Women who had no change in mammography constituted group I (n = 23). Women who had a change constituted group II (n = 2). Although the initial hormone levels were not different, the increase in serum DHEAS in group I was significantly higher than in group II (z = 2.30, P = 0.021).

CONCLUSION(S)

The frequency of mammographic changes in women receiving tibolone therapy was found to be 8% at the end of the 24-month follow-up. The serum DHEAS level may be an important hormonal marker complementary to mammographic screening for women receiving tibolone therapy. We strongly believe that tibolone is safe in terms of mammographic changes in postmenopausal women.

Depressed skull fracture overlying the superior sagittal sinus as a cause of benign intracranial hypertension. Case report

The use of surgical treatment for depressed skull fractures that are located over major venous sinuses is a matter of controversy. However, if clinical and radiological findings of sinus obliteration and related intracranial hypertension are present, surgical decompression is indicated. The authors present the case of a 38-year-old man who had a depressed skull fracture overlying the posterior one-third portion of the superior sagittal sinus. The lesion was initially treated conservatively and the patient was readmitted 1 month later with signs and symptoms of intracranial hypertension. The role of radiological investigation in the detection of venous sinus flow and indications for surgical treatment are discussed. If venous sinus flow obstruction is revealed in the presence of signs and symptoms of intracranial hypertension, surgery is indicated as the first line of treatment.

Radiologic evaluation of gastrointestinal leiomyosarcomatosis

A 68-year-old woman who had previously undergone small intestinal resection because of leiomyosarcoma was referred to our clinic with epigastric pain. A double-contrast barium study and the subsequent abdominopelvic CT and abdominal MRI examinations demonstrated multiple extraluminal growing tumors arising from the walls of stomach, small bowel, and colon. A CT-guided aspiration biopsy revealed malignant mesenchymal tumor. The presence of disseminated intra-abdominal masses without concomitant ascites and invasion of tissue planes on CT in a patient operated on prior because of a leiomyosarcoma led to the diagnosis of gastrointestinal leiomyosarcomatosis. In this report we discuss the radiological approach to this rare entity.

Mammographic changes in women on hormonal replacement therapy

OBJECTIVES

In the present retrospective study, we aimed to determine the frequency and the types of mammographic changes of breast parenchyma in women receiving hormone replacement therapy (HRT). We also investigated whether there was an association between mammographic changes and some clinical and hormonal characteristics of the women on HRT.

METHODS

One-hundred and eight women were included into the study. Of the 108 women, 19 were climacteric, four premature menopause, 50 spontaneous menopause and 35 surgical menopause. Prior to the start of HRT, an initial mammography was performed and it was repeated at 6- to 18-month intervals according to the women's status. Estrogen alone was started for 35 surgical menopause women and a combination of estrogen plus progesterone for the remaining 73 women.

RESULTS

Group I consisted of 96 women with no parenchymal changes or a decrease in parenchymal density on mammography, whereas group II consisted of 12 women with an increase in parenchymal density (11%) during the mean period of 24 months. Endogenous E2 levels were significantly higher in group II than in group I (52.4 +/- 42.3 pg/ml vs. 32.3 +/- 29.3 pg/ml, P < 0.05). Climacterium or types of menopause did not affect the mammographical density changes. Neither the type nor the duration of HRT had an effect on mammographic density increase.

CONCLUSIONS

We concluded that the endogenous E2 level might be an important role in screening the women mammographically. Long-term follow-up studies were concluded to be needed in order to evaluate the effects of HRT on mammographic changes.