Utility of 'dual phase' cone beam computed tomography during radioembolisation in patients with hepatocellular carcinoma: what is really changing in flow dynamics before and after 90Y delivery?

PURPOSE: The aims of the study were: 1) to compare two phases of dual-phase cone beam computed tomography (DP-CBCT) achieved before and after Yttrium-90 (90Y) administration and to evaluate additional benefits during radioembolisation (RE) procedures; and 2) to compare DP-CBCT with pre-procedure contrast enhanced cross-sectional images in terms of tumour detection. MATERIAL AND METHODS: Twenty-three hepatocellular carcinoma patients undergoing RE treatment were scanned with DP-CBCT consisting of early arterial (EA) and late arterial (LA) phases before and after 90Y administration. The CT-like datasets were compared according to embolisation effect, enhancement patterns, lesion detectability, image quality, and artifacts by two interventional radiologists blinded to each other. The compatibility of the two radiologists was evaluated with kappa statistical analysis, and the difference between EA and LA phases was evaluated with marginal homogeneity test. Also, DP-CBCT images were compared with preprocedural cross-sectional images (CT/MRI). RESULTS: For 23 patients 92 data were acquired. Thirteen patients showed a decrease on post-embolisation images both visually and on Hounsfield unit (HU) measurements. No statistical difference was found for tumour detection between EA and LA phases (p = 1.0). Tumour enhancement was visually superior at LA phases whereas EA phases were better for arterial mapping for selective catheterisation. DP-CBCT images were not inferior to preprocedural cross-sectional imaging findings. CONCLUSIONS: DP-CBCT is a promising tool for predicting tumour response to therapy and is not inferior to preprocedural cross-sectional imaging in terms of tumour detection. It allows better assessment during RE procedures because early phases provide good mapping for superselective catheterisation whereas late phases are better for visualisation of tumour enhancement.

Effects of cavity reconstruction on morbidity and quality of life after canal wall down tympanomastoidectomy / Efeitos da reconstrução da cavidade da timpanomastoidectomia com técnica aberta na morbidade e qualidade de vida

Abstract Introduction: Canal wall down tympanomastoidectomy is commonly used to treat advanced chronic otitis media or cholesteatoma. The advantages of canal wall down mastoidectomy are excellent exposure for disease eradication and postoperative control of residual disease; its disadvantages include the accumulation of debris requiring life-long otological maintenance and cleaning, continuous ear drainage, fungal cavity infections, and the occurrence of dizziness and vertigo by changing temperature or pressure. Objective: To evaluate whether cavity-induced problems can be eliminated and patient comfort can be increased with mastoid cavity reconstruction. Methods: In total, 11 patients who underwent mastoid cavity reconstruction between March 2013 and June 2013 comprised the study group, and 11 patients who had dry, epithelialized CWD cavities were recruited as the control group. The study examined three parameters: epithelial migration, air caloric testing, and the Glasgow Benefit Inventory. Epithelial migration, air caloric testing, and the Glasgow Benefit Inventory were evaluated in the study and control groups. Results: The epithelial migration rate was significantly faster in study group (1.63 ± 0.5 mm/week) than control group (0.94 ± 0.37 mm/week) (p = 0.003, p < 0.05). The mean slow component velocity of nystagmus of the study group (13.33 ± 5.36°/s) was significantly lower when compared to control group (32.11 ± 9.12°/s) (p = 0.018). The overall the Glasgow Benefit Inventory score was −7.21, and the general subscale, physical and social health scores were −9.71, −21.09, and +20.35, respectively in the control group. These were +33.93, +35.59, +33.31, and +29.61, respectively in the study group. All but the social health score improved significantly (0.007, 0.008, 0.018, and 0.181, respectively). Conclusions: Cavity reconstruction improves epithelial migration, normalizes caloric responses and increases the quality of life. Thus, cavity rehabilitation eliminates open-cavity-induced problems by restoring the functional anatomy of the ear.

Resumo Introdução: A timpanomastoidectomia com a técnica Canal Wall Down, ou técnica aberta, é comumente utilizada para tratar otite média crônica avançada ou colesteatoma. As vantagens da mastoidectomia pela técnica aberta são uma excelente exposição para a erradicação da doença e controle pós-operatório da doença residual; suas desvantagens incluem o acúmulo de detritos que requerem manutenção e limpeza otológica ao longo da vida, drenagem contínua da orelha, infecções fúngicas na cavidade e a ocorrência de tonturas e vertigem com alterações de temperatura ou pressão. Objetivo: Avaliar se os problemas induzidos pela cavidade podem ser eliminados e o conforto do paciente aumentado com a reconstrução da cavidade mastoide. Método: No total, 11 pacientes submetidos à reconstrução da cavidade mastoide entre março de 2013 e junho de 2013 constituíram o grupo de estudo, e 11 pacientes com cavidades secas e epitelizadas, operadas pela técnica aberta, foram recrutados como grupo controle. O estudo analisou três parâmetros: migração epitelial, prova calórica com estimulação a ar e o questionário Glasgow Benefit Inventory. A migração epitelial, a prova calórica e o Glasgow Benefit Inventory foram avaliados nos grupos de estudo e controle. Resultados: A taxa de migração epitelial foi significativamente mais rápida no grupo de estudo (1,63 ± 0,5 mm/semana) do que no grupo controle (0,94 ± 0,37 mm/semana) (p = 0,003, p < 0,05). A velocidade média do componente lento do nistagmo no grupo de estudo (13,33 ± 5,36°/s) foi significativamente menor se comparada ao grupo controle (32,11 ± 9,12°/s) (p = 0,018). O escore global do Glasgow Benefit Inventory foi de -7,21 e os escores da subescala geral, saúde física e social foram -9,71, -21,09 e +20,35, respectivamente, no grupo controle. Esses escores foram +33,93, +35,59, +33,31 e +29,61, respectivamente, no grupo de estudo. Todos, exceto o escore de saúde social, melhoraram significativamente (0,007, 0,008, 0,018 e 0,181, respectivamente). Conclusões: A reconstrução da cavidade melhora a migração epitelial, normaliza as respostas da prova calórica e aumenta a qualidade de vida. Assim, a reabilitação da cavidade elimina os problemas induzidos por cavidades abertas ao restaurar a anatomia funcional da orelha.

Effects of cavity reconstruction on morbidity and quality of life after canal wall down tympanomastoidectomy.

INTRODUCTION: Canal wall down tympanomastoidectomy is commonly used to treat advanced chronic otitis media or cholesteatoma. The advantages of canal wall down mastoidectomy are excellent exposure for disease eradication and postoperative control of residual disease; its disadvantages include the accumulation of debris requiring life-long otological maintenance and cleaning, continuous ear drainage, fungal cavity infections, and the occurrence of dizziness and vertigo by changing temperature or pressure. OBJECTIVE: To evaluate whether cavity-induced problems can be eliminated and patient comfort can be increased with mastoid cavity reconstruction. METHODS: In total, 11 patients who underwent mastoid cavity reconstruction between March 2013 and June 2013 comprised the study group, and 11 patients who had dry, epithelialized CWD cavities were recruited as the control group. The study examined three parameters: epithelial migration, air caloric testing, and the Glasgow Benefit Inventory. Epithelial migration, air caloric testing, and the Glasgow Benefit Inventory were evaluated in the study and control groups. RESULTS: The epithelial migration rate was significantly faster in study group (1.63±0.5mm/week) than control group (0.94±0.37mm/week) (p=0.003, p<0.05). The mean slow component velocity of nystagmus of the study group (13.33±5.36°/s) was significantly lower when compared to control group (32.11±9.12°/s) (p=0.018). The overall the Glasgow Benefit Inventory score was -7.21, and the general subscale, physical and social health scores were -9.71, -21.09, and +20.35, respectively in the control group. These were +33.93, +35.59, +33.31, and +29.61, respectively in the study group. All but the social health score improved significantly (0.007, 0.008, 0.018, and 0.181, respectively). CONCLUSIONS: Cavity reconstruction improves epithelial migration, normalizes caloric responses and increases the quality of life. Thus, cavity rehabilitation eliminates open-cavity-induced problems by restoring the functional anatomy of the ear.

A Case of Pseudoaneurysm of the Internal Carotid Artery Following Endoscopic Endonasal Pituitary Surgery: Endovascular Treatment with Flow-Diverting Stent Implantation.

Internal carotid artery (ICA) pseudoaneurysm is a rare complication of endoscopic endonasal surgery occurring in 0.4-1.1% of cases. Pseudoaneurysms can subsequently result in other complications, such as subarachnoid hemorrhage, epistaxis, and caroticocavernous fistula with resultant death or permanent neurologic deficit. In this case, we illustrate endovascular treatment with a flow-diverting stent for an ICA pseudoaneurysm after endoscopic endonasal surgery for a pituitary adenoma in a 56-year-old male. Surgery was complicated by excessive intraoperative bleeding and emergent CT angiography confirmed an iatrogenic pseudoaneurysm on the anteromedial surface of the ICA. The pseudoaneurysm was treated endovascularly with flow-diverting stent implantation only. Follow-up CT angiography after three months demonstrated occlusion of the pseudoaneurysm.

Intra-Arterial Radionuclide Therapies for Liver Tumors.

Intra-arterial radionuclide therapies serve essentially as internal radiation treatment options for both primary and metastatic liver tumors, which imply delivering implantable radioactive microspheres into branches of hepatic arteries that feed liver tumors to provide a high dose of targeted radiation to tumor tissue, while sparing the healthy liver tissue from hazardous effects of radiation. The principle of this therapeutic option depends on the unique preferential arterial supply of malignant liver tumors in contrast with mostly portal venous supply of normal hepatocytes as well as excess amount of arterial neovascularization in the tumor bed. Therefore, intra-arterial radionuclide therapy can provide very high radiation exposure to tumor tissue, which is impossible to reach with external radiation therapy due to serious side effects and moreover, radiation can be targeted to tumor tissue selectively with less side effects. Yttrium-90 (Y-90), a high-energetic beta emitter is the most preferred radionuclide, which is used to label microspheres. Two types of Y-90 microspheres are commercially available that are made of resin and glass. Many studies in the literature have demonstrated that Y-90 microsphere therapy is an efficient and safe locoregional therapeutic option for unresectable primary and metastatic liver tumors such as hepatocellular carcinoma and liver metastases from colorectal cancer and breast cancer as well as neuroendocrine tumors. Furthermore, limited number of studies has reported its use in some relatively uncommon metastatic liver tumors from melanoma, pancreatic, renal, and lung cancer. Besides Y-90 microspheres, Iodine-131 lipiodol, Rhenium-188 lipiodol, Rhenium-188 microspheres, Holmium-166 chitosan, and Holmium-166 microspheres have been introduced as alternative radiopharmaceuticals for intra-arterial therapy for liver tumors.

Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin

OBJECTIVE: The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets. Study DESIGN: A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contralateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed in the same control sessions. Dependent group t test for paired samples was used for statistical analysis. RESULTS: The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 30 and 90 days postoperatively. Radioopacity that can show the bone healing on panoramic images were measured by Image J programme and they did not differ significantly. Also periodontal values did not differ significantly. CONCLUSIONS: PRF might not lead to enhanced bone healing in impacted mandibular third molar extraction sockets30 and 90 days after surgery. It is thought that PRF has the potential characteristics of an autologous fibrin matrix and can accelerate the healing. To better understand the effects of PRF on healing, further research is warranted with larger sample sizes

Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin.

OBJECTIVE: The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets. STUDY DESIGN: A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contralateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed in the same control sessions. Dependent group t test for paired samples was used for statistical analysis. RESULTS: The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 30 and 90 days postoperatively. Radio-opacity that can show the bone healing on panoramic images were measured by Image J programme and they did not differ significantly. Also periodontal values did not differ significantly. CONCLUSIONS: PRF might not lead to enhanced bone healing in impacted mandibular third molar extraction sockets 30 and 90 days after surgery. It is thought that PRF has the potential characteristics of an autologous fibrin matrix and can accelerate the healing. To better understand the effects of PRF on healing, further research is warranted with larger sample sizes.

Squamous cell carcinoma originating from the nasal septal perforation: a rare nasal tumor.

Primary squamous cell carcinoma of the nasal septum is an extremely rare malignancy. In this article, we report a case of 52-year-old female with a complaint of nasal obstruction along with occasional nasal bleeding for one year. Endoscopy showed a 2.5x2 cm perforation originating from the anterior nasal septum. Incisional biopsy result was reported as squamous cell carcinoma. The tumor was removed by functional endoscopic surgery. Histopathological examination revealed squamous cell carcinoma with safe surgery borders. No recurrence and complications were noticed after one year of follow-up. The functional impact of the treatment with high mortality rates highlights the importance of early diagnosis. We recommend the differential diagnosis of septal perforation and early wide surgical excision for such cases.

Recurrent meningitis and frontal encephalocele as delayed complications of craniofacial trauma.

Frontal sinus back table fractures are seen rarely; also, typical presentation of frontal sinus encephalocele as a delayed complication of frontal sinus fracture is seen more rarely. We present a case of frontal encephalocele and recurrent meningitis as delayed complications of craniofacial trauma. Diagnosis, management, and treatment approaches of these complications are discussed.

The Diagnostic Efficiency of 99mTc-EDDA/HYNIC-Octreotate SPECT-CT in Comparison with 111In-Pentetrotide in the Detection of Neuroendocrine Tumours.

OBJECTIVE: The aim of this study was to assess the diagnostic efficiency of (99m)Tc-EDDA/HYNIC-Octreotate in comparison with (111)Inpentetrotide scintigraphy in the detection of neuroendocrine tumors. This study also evaluates the impact of SPECT-CT hybrid imaging on somatostatin receptor scintigraphy (SRS) interpretation and clinical management of these tumors. METHODS: Fourteen patients were included in the study. All patients underwent a whole body and SPECT-CT imaging with both (99m)Tc- EDDA/HYNIC-octreotate and (111)In-pentetrotide. Images were evaluated both visually and semiquantitatively. RESULTS: On patient basis, the diagnostic results of both studies were similar. The number of lesions detected by (99m)Tc- EDDA/HYNICOctreotate were higher than the number of lesions detected by (111)In-pentetrotide however the difference was not significant (40/43( 93%), 36/43 (83%) p=0.109). Semiquantitative analysis showed higher tumor/organ count ratios for both whole-body and SPECT (99m)Tc- EDDA/HYNIC-Octreotate scans. CONCLUSION: The results of this study suggested that, (99m)Tc- EDDA/HYNIC-Octreotate may be a better alternative to (111)In- pentetrotide due to high image quality and lower radiation dose. SPECT/CT is a valuable tool for the assessment of neuroendocrine tumors by providing the precise anatomic localization of scintigraphic findings thus improving lesion detectability and characterization. CONFLICT OF INTEREST: None declared.

The relation between perfusion pattern of hepatic artery perfusion scintigraphy and response to y-90 microsphere therapy.

OBJECTIVE: Hepatic artery perfusion scintigraphy is a routine procedure for patient evaluation before Y-90 radiomicrosphere therapy and mostly used for prediction of extrahepatic leakage. Moreover, it also displays perfusion pattern of tumours, which is an important parameter on success of the therapy. The aim of this study is to assess the relation between the perfusion pattern on hepatic artery perfusion scintigraphy and radiomicrosphere therapy response. METHODS: A total of 99 radiomicrosphere therapy applications were carried out in 80 patients (M/F: 55/25). RESULTS: Heterogeneous and diffuse perfusion patterns were observed in 47 patients and 52 patients, respectively. The patients with diffuse perfusion pattern had better therapy response both on FDG PET/CT (p= 0.04) and CT (p=0.008) when compared to those with heterogenous perfusion pattern. CONCLUSION: Perfusion pattern observed on hepatic artery perfusion scintigraphy may be a successful predictor of early response to radiomicrosphere therapy. CONFLICT OF INTEREST: None declared.

Nanosized multifunctional liposomes for tumor diagnosis and molecular imaging by SPECT/CT.

Among currently used cancer imaging methods, nuclear medicine modalities provide metabolic information, whereas modalities in radiology provide anatomical information. However, different modalities, having different acquisition times in separate machines, decrease the specificity and accuracy of images. To solve this problem, hybrid imaging modalities were developed as a new era, especially in the cancer imaging field. With widespread usage of hybrid imaging modalities, specific contrast agents are essentially needed to use in both modalities, such as single-photon emission computed tomography/computed tomography (SPECT/CT). Liposomes are one of the most desirable drug delivery systems, depending on their suitable properties. The aim of this study was to develop a liposomal contrast agent for the diagnosis and molecular imaging of tumor by SPECT/CT. Liposomes were prepared nanosized, coated with polyethylene glycol to obtain long blood circulation, and modified with monoclonal antibody 2C5 for specific tumor targeting. Although DTPA-PE and DTPA-PLL-NGPE (polychelating amphilic polymers; PAPs) were loaded onto liposomes for stable radiolabeling for SPECT imaging, iopromide was encapsulated into liposomes for CT imaging. Liposomes [(DPPC:PEG(2000)-PE:Chol:DTPA-PE), (PL 90G:PEG(2000)-PE:Chol:DTPA-PE), (DPPC:PEG(2000)-PE:Chol:PAPs), (PL 90G:PEG(2000)-PE:Chol:PAPs), (60:0.9:39:0.1% mol ratio)] were characterized in terms of entrapment efficiency, particle size, physical stability, and release kinetics. Additionally, in vitro cell-binding studies were carried out on two tumor cell lines (MCF-7 and EL 4) by counting radioactivity. Tumor-specific antibody-modified liposomes were found to be effective multimodal contrast agents by designating almost 3-8 fold more uptake than nonmodified ones in different tumor cell lines. These results could be considered as an important step in the development of tumor-targeted SPECT/CT contrast agents for cancer imaging.

[Anatomical and functional results of open cavity tympanomastoidectomy]. / Açik kavite timpanomastoidektominin anatomik ve fonksiyonel sonuçlari

OBJECTIVES: In this study, we aimed to evaluate the anatomical and functional results of open cavity tympanomastoidectomy due to chronic otitis media with cholesteatoma. PATIENTS AND METHODS: Between January 2003 and October 2009, 166 patients who underwent open cavity tympanomastoidectomy due to chronic otitis media with cholesteatoma in our clinic were retrospectively analyzed. Seventy-two ears of 69 patients (40 males, 29 females; mean age 36.7±17.7 years; range 9 to 64 years) who visited on a regular basis due to acquired middle ear cholesteatoma were included. Cholesteatoma was classified as attic, sinus and tensa retraction cholesteatoma, according to its localization. Audiological findings were compared based on the localization of cholesteatoma and intraoperative ossicular status. RESULTS: The mean follow-up was 36.3±27.0 months (range 6 to 88 months). There were six (8.4%) greft failures, four (5.6%) graft retractions, and one (1.4%) recurrent cholesteatomas in the ears of the patients. There were also five (7%) pearly residual cholesteatomas. At the last visit following surgery, 97.2% of cavities were dry and self-cleaning. The mean preoperative pure tone air threshold was 53.5±22 dB, while it reduced to 52.2±23.3 dB at the last visit in 48 ears operated open cavity tympanomastoidectomy type 1, 2, 3, and 4 in combination with hearing reconstruction (p=0.454). There was a statistically significant reduction in the mean air-bone gap of the attic cholesteatomas, decreasing from 27.2±14.6 dB to 21.6±12.2 dB (p=0.007). Air-bone gap values were lower than 20 dB in 23 (47.9%) of the cases and the gain was more than 10 dB in 17 (35.5%). No statistically significant correlation was found between the localization of cholesteatoma and intraoperative ossicular status (p>0.05). CONCLUSION: Open cavity tympanomastoidectomy, which allows total removal of the pathology, is an applicable surgical approach with satisfactory outcomes for hearing reconstruction.

Comparison of 800 and 3700 MBq iodine-131 for the postoperative ablation of thyroid remnant in patients with low-risk differentiated thyroid cancer.

INTRODUCTION: The initial treatment of differentiated thyroid cancer is thyroidectomy, followed by remnant ablation with iodine-131 (I-131) in some patients. However, controversy exists concerning the appropriate radioiodine dose. The aim of the study is to compare the success rate of low and high activities of I-131 for postoperative remnant ablation. PATIENTS AND METHODS: A total of 108 nonmetastatic low-risk patients (mean age: 46, 85% women) with papillary and follicular carcinoma had I-131 ablation for the postoperative thyroid remnant. Fifty-three patients received a low dose (L) (800 MBq) and 55 patients received a high dose (H) (3700 MBq) of I-131. After total thyroidectomy, thyroid bed I-131 uptake (RAIU) and neck ultrasonography (USG) were performed to determine the remnant volume and the iodine avidity, which were used to calculate the dose delivered to the remnant tissue. The success rate of I-131 ablation was assessed with four different criteria based on serum thyroglobulin (Tg) and USG with and without the utilization of I-131 diagnostic whole-body scintigraphy (DxWBS). Ablation was considered to be successful if patients fulfilled all of the following criteria. (a) Strict criteria based on three tests: (i) USG negative, (ii) no tracer uptake or less than twice the background activity in the thyroid bed on DxWBS and/or up to 0.2% RAIU, and (iii) Tg < 0.2 ng/ml; (b) lax criteria based on three tests: (i) USG negative, (ii) no tracer uptake or less than twice the background activity in the thyroid bed on DxWBS and/or ≤ 0.2% RAIU, and (iii) Tg < 2 ng/ml; (c) strict criteria based on two tests: (i) USG negative and (ii) Tg < 0.2 ng/ml; (d) lax criteria based on two test: (i) USG negative and (ii) Tg < 2 ng/ml. RESULTS: When three tests were used to define successful ablation, in group L, 32 out of 53 (60%) and 43 out of 53 (81%) patients were successfully treated versus 35 out of 55 (64%) and 42 out of 55 (76%) for group H on the basis of strict and lax criteria, respectively (P=NS). The differences were not statistically significant between the two groups when only two tests were used to define ablation success (62 vs. 69% with strict and 89 vs. 87% with lax criteria, respectively). CONCLUSION: Our findings suggest that remnant thyroid tissue in patients with low-risk, well-differentiated thyroid cancer after total thyroidectomy can be ablated with 800 MBq of I-131. The success rate is not different from that obtained with 3700 MBq I-131.

Experience with nuclear medicine information system.

OBJECTIVE: Radiology information system (RIS) is basically evolved for the need of radiologists and ignores the vital steps needed for a proper work flow of Nuclear Medicine Department. Moreover, CT/MRI oriented classical PACS systems are far from satisfying Nuclear Physicians like storing dynamic data for reprocessing and quantitative analysis of colored images. Our purpose was to develop a workflow based Nuclear Medicine Information System (NMIS) that fulfills the needs of Nuclear Medicine Department and its integration to hospital PACS system. MATERIAL AND METHODS: Workflow in NMIS uses HL7 (health level seven) and steps include, patient scheduling and retrieving information from HIS (hospital information system), radiopharmacy, acquisition, digital reporting and approval of the reports using Nuclear Medicine specific diagnostic codes. Images and dynamic data from cameras of are sent to and retrieved from PACS system (Corttex©) for reprocessing and quantitative analysis. RESULTS: NMIS has additional functions to the RIS such as radiopharmaceutical management program which includes stock recording of both radioactive and non-radioactive substances, calculation of the radiopharmaceutical dose for individual patient according to body weight and maximum permissible activity, and calculation of radioactivity left per unit volume for each radionuclide according their half lives. Patient scheduling and gamma camera patient work list settings were arranged according to specific Nuclear Medicine procedures. Nuclear Medicine images and reports can be retrieved and viewed from HIS. CONCLUSION: NMIS provides functionality to standard RIS and PACS system according to the needs of Nuclear Medicine. CONFLICT OF INTEREST: None declared.

Computerized scar detection on renal cortical scintigraphy images.

OBJECTIVE: Renal cortical scintigraphy is a well-established functional imaging technique for visual analysis of radiopharmaceutical tracer distribution. However, the visual evaluation is subjective, causing interobserver variability, especially in a quantifiable number of scars. The purpose of this study was to develop new computerized methods in renal cortical scintigraphy image interpretation, particularly addressing activity distribution and cortex continuity (scars). METHODS: The proposed methods involve preprocessing stages of model-based automatic kidney segmentation using active-shape model and image normalization (transforming each kidney image into a standardized image vector). For our previous computer-aided diagnosis scheme, two new image-based features [localized activity drop and principal component analysis (PCA)] were defined. Their performance was evaluated and compared with our previous scheme by using free-response receiver operating characteristic that is in terms of sensitivity (true-positive fraction) and the mean number of false positives (FPs) per image. RESULTS: Clinical tests were conducted in 297 patients (231 normal and 66 abnormal). The PCA-based image feature presented the best scar detection performance, followed by the localized activity drop feature. Both schemes were found to be superior to our previous computer-aided diagnosis scheme. In the PCA-based scheme, for sensitivity of 0.90 (76/84), the mean number of FPs was measured as 4.52 (1343/297). For another setting with reduced sensitivity of 0.79 (66/84), the mean number of FPs improved to 1.21 (360/297). Finally, a decision fusion scheme using 'majority voting' was also proposed, the sensitivity and mean number of FPs of which were measured as 0.83 (70/84) and 1.90 (563/297), respectively. CONCLUSION: The proposed methods have potential to provide effective second-reader information to nuclear medicine specialists in finding scar regions. Possible ways to improve the FP rate were also proposed.

Radioembolization for the treatment of unresectable liver cancer: initial experience at a single center.

PURPOSE: Radioembolization with yttrium-90 microsphere (Y-90) therapy with SIR-Spheres (Sirtex Medical, Lane Cove, Australia) was approved by the Turkish Ministry of Health in April 2008. In this study, we present the preliminary experience at a tertiary care center with early follow-up results of Y-90 therapy, as well as a review of the related literature. MATERIALS AND METHODS: Complete evaluation for radioembolization was performed in 10 patients (8 males, 2 females; mean age, 52.3 years) during an 8-month period at a single center, of which 9 were actually treated with SIR-Spheres(R). All patients underwent meticulous pre- and post-procedural imaging studies to document the therapy response. RESULTS; In order to isolate the target hepatic arterial circulation, following branches were embolized as they were considered as potential gastrointestinal shunts: the gastroduodenal artery (n = 5), right gastric artery (n = 1), and supraduodenal artery (n = 1). Radioembolization therapy could not be performed only in one patient because of a hepatogastric shunt of unknown origin. No significant hepatopulmonary shunting was identified (maximum, 9% shunting). The body surface area method was used to calculate the Y-90 dose in all patients (mean dose, 1.24 GBq). All patients had at least partial response of the targeted liver lesions, according to RECIST (Response Evaluation Criteria in Solid Tumors). CONCLUSION: In comparison to chemoembolization, radioembolization has less systemic toxicity and can be performed as an outpatient procedure, which makes it more attractive to both patients and physicians. From our limited experience, the radioembolization procedure is a promising first-line treatment in unresectable liver cancer; randomized controlled multi-center studies, however, are needed.

Analysis of dendritic cells in sentinel lymph nodes of patients with endometrial and patients with cervical cancers.

OBJECTIVE: The aim of this study was to identify the immune response in sentinel lymph nodes (SLNs) of patients with endometrial and patients with cervical cancers by analyzing the number of S-100-, CD1a-, CD83-positive (+) dendritic cells that are the major antigen-presenting cells. METHODS: A total of 56 patients with early-stage cancer (n = 32, with cervical; n = 24, with endometrial cancer) underwent SLN biopsy. Sentinel lymph nodes and non-SLNs were stained with antibodies against S-100, CD1a, and CD83 as markers for dendritic cells to find out whether SLNs were immunomodulated compared with non-SLNs. RESULTS: The mean values of S-100(+) and CD1a(+) dendritic cells in both the tumor-free and the metastatic SLNs were significantly higher than those of both the tumor-free and the metastatic non-SLNs. When metastatic SLNs were compared with nonmetastatic SLNs, CD83(+) dendritic cells were found significantly more abundant in nonmetastatic SLNs. CONCLUSIONS: Significantly higher numbers of S-100(+) and CD1a(+) dendritic cells in the SLNs compared with those in the non-SLNs may indicate that SLNs are the first sites of immunostimulation. Immunosupression may be the underlying factor for the metastatic involvement of SLNs, which might be secondary to the significantly decreased number of mature dendritic cells in metastatic SLNs compared with tumor-free SLNs.

2009 EANM parathyroid guidelines.

The present guidelines were issued by the Parathyroid Task Group of the European Association of Nuclear Medicine. The main focus was imaging of primary hyperparathyroidism. Dual-tracer and single-tracer parathyroid scintigraphy protocols were discussed as well as the various modalities of image acquisition. Primary hyperparathyroidism is an endocrine disorder with high prevalence, typically caused by a solitary parathyroid adenoma, less frequently (about 15%) by multiple parathyroid gland disease (MGD) and rarely (1%) by parathyroid carcinoma. Patients with MGD may have a double adenoma or hyperplasia of three or all four parathyroid glands. Conventional surgery has consisted in routine bilateral neck exploration. The current trend is toward minimally invasive surgery. In this new era, the success of targeted parathyroid surgery depends not only on an experienced surgeon, but also on a sensitive and accurate imaging technique. Recognizing MGD is the major challenge for pre-operative imaging, in order to not direct a patient towards inappropriate minimal surgery. Scintigraphy should also report on thyroid nodules that may cause confusion with a parathyroid adenoma or require concurrent surgical resection. The two main reasons for failed surgery are ectopic glands and undetected MGD. Imaging is mandatory before re-operation, and scintigraphy results should be confirmed with a second imaging technique (usually US for a neck focus, CT or MRI for a mediastinal focus). Hybrid SPECT/CT instruments should be most helpful in this setting. SPECT/CT has a major role for obtaining anatomical details on ectopic foci. However, its use as a routine procedure before target surgery is still investigational. Preliminary data suggest that SPECT/CT has lower sensitivity in the neck area compared to pinhole imaging. Additional radiation to the patient should also be considered. The guidelines also discuss aspects related to radio-guided surgery of hyperparathyroidism and imaging of chronic kidney disease patients with secondary hyperparathyroidism.

Functional nuclear medicine imaging of medullary thyroid cancer.

Medullary thyroid cancer (MTC) originates from parafollicular C cells of the thyroid and accounts for 3-12% of all thyroid cancers. As opposed to other types of dedifferentiated thyroid tumours, MTC cells are highly functional, producing and secreting high amounts of calcitonin and carcinoembryonic antigen. As parafollicular C cells are of neural crest origin, MTC acts as a neuroendocrine tumour also and expresses somatostatin receptors. Although conventional radiological methods such as ultrasonography, computed tomography and magnetic resonance imaging are widely used in the primary diagnosis and staging, they often fail to localize the residual or recurrent disease because the majority of MTC recurrence presents as occult disease. Thus, owing to functional characteristics of MTC, functional imaging modalities of nuclear medicine play a major role in the diagnostic and therapeutic strategies for MTC. Among nuclear medicine modalities, Tc(V) -dimercaptosuccinic acid, In-octreotide and I/I-meta-iodobenzylguanidine are commonly used in the diagnostic and even more in postoperative work-up of MTC. Alternatively, F-fluorodeoxyglucose and other positron emission tomography radiopharmaceuticals such as F-fluorodopa or F-fluorodopamine as well as radiolabelled antibodies such as Tc/I/I anticarcinoembryonic antigen, antigastrin, and anticholecystokinin-B have promising results. Functional imaging has a great advantage for nuclear medicine techniques in the routine work-up of MTC patients and also has a wide use in experimental studies.