METHODS: Cross sectional observational cohort study. Subjects with normal eyes were recruited. Two sets of optical coherence tomography angiography images of macula and optic nerve head were acquired during one visit. Novel in-house developed software was used to count the pixels in each images and to compute the microvessel density of the macula and optic disc. Data were analysed to determine the measurement repeatability.

RESULTS: A total of 176 eyes from 88 consecutive normal subjects were recruited. For macular images, the mean vessel density at superficial retina, deep retina, outer retina and choriocapillaries segment was OD 0.113 and OS 0.111, OD 0.239 and OS 0.230, OD 0.179 and OS 0.164, OD 0.237 and OS 0.215 respectively. For optic disc images, mean vessel density at vitreoretinal interface, radial peripapillary capillary, superficial nerve head and disc segment at the level of choroid were OD 0.084 and OS 0.085, OD 0.140 and OS 0.138, OD 0.216 and OS 0.209, OD 0.227 and OS 0.236 respectively. The measurement repeatability tests showed that the coefficient of variation of macular scans, for right and left eyes, ranged from 6.4 to 31.1% and 5.3 to 59.4%. Likewise, the coefficient of variation of optic disc scans, for right and left eyes, ranged from 14.3 to 77.4% and 13.5 to 75.3%.

CONCLUSIONS: Optical coherence tomography angiography is a useful modality to visualise the microvasculature plexus of macula and optic nerve head. The vessel density measurement of macular scan by mean of optical coherence tomography angiography demonstrated good repeatability. The optic disc scan, on the other hand, showed a higher coefficient of variation indicating a lower measurement repeatability than macular scan. Interpretation of optical coherence tomography angiography should take into account test-retest repeatability of the imaging system.

MATERIALS AND METHODS: Two hundred fifty-eight patients with primary liver tumors who underwent FDG-PET before LDLT were enrolled in this retrospective study. Unfavorable tumor histology was defined as primary liver tumor other than a well- or moderately differentiated HCC. Thirteen patients had unfavorable tumor histology, including 2 poorly differentiated HCC, 2 sarcomatoid HCC, 5 combined hepatocellular cholangiocarcinoma, 3 intrahepatic cholangiocarcinoma, and 1 hilar cholangiocarcinoma.

RESULTS: FDG-PET positivity was significantly associated with unfavorable tumor histology (P < 0.001). Both FDG-PET positivity and unfavorable tumor histology were significant independent predictors of tumor recurrence and overall survival. In a subgroup analysis of patients with FDG-PET-positive tumors, unfavorable tumor histology was a significant independent predictor of tumor recurrence and overall survival. High FDG uptake (tumor to non-tumor uptake ratio ≥ 2) was a significant predictor of unfavorable tumor histology. Patients with high FDG uptake and/or unfavorable tumors had significantly higher 3-year cumulative recurrence rate (70.8% versus 26.2%, P = 0.004) and worse 3-year overall survival (34.1% versus 70.8%, P = 0.012) compared to those with low FDG uptake favorable tumors.

PRESENTATION OF CASE: A 19-year-old lady presented with a bleeding, fungating breast mass worsened with topical herbal concoction. Examination revealed a 10 × 15 cm fungating breast mass that obliterated her nipple- areolar complex (NAC). Computed Tomography (CT) scan reported a huge heterogeneously enhancing mass 10.6 × 14.5 × 15.1 cm with loss of normal fat plane with the overlying skin but a clear fat plane with the pectoralis muscle posteriorly.

DISCUSSION: Giant breast masses that fungate and ulcerate usually indicate a sinister pathology. Traditional remedies have been reported to exacerbate growth. In cases where most of the breast parenchyma and NAC has been destroyed, it is no longer possible to proceed with breast conserving techniques. Breast reconstruction is crucial in adolescents and should be tailored to the patient's existing breast size as well as body habitus.

METHODS: Consecutive patients with a new histological diagnosis of LAPC were recruited over 20 months. Baseline CT and 18FDG PET-CT were performed and repeated after 12 weeks to assess response to treatment. Following 2 cycles of conventional chemotherapy, patients underwent EUS-guided 32P OncoSil implantation followed by a further six cycles of chemotherapy.

RESULTS: Twelve patients with LAPC (8M:4F; median age 69 years, IQR 61.5-73.3) completed the treatment. Technical success was 100% and no procedural complications were reported. At 12 weeks, there was a median reduction of 8.2cm3 (95% CI 4.95-10.85; p=0.003) in tumour volume, with minimal or no 18FDG uptake in 9 (75%) patients. Tumour downstaging was achieved in 6 (50%) patients, leading to successful resection in 5 (42%) patients, of which 4 patients (80%) had clear (R0) resection margins.

METHODS: The pre- and post-operative CT images of 55 patients undergoing DC surgery were analyzed. The ICV was measured by segmenting every slice of the CT images, and compared with estimated ICV calculated using the 1-in-10 sampling strategy and processed using the SBI method. An independent t test was conducted to compare the ICV measurements between the two different methods. The calculation using this method was repeated three times for reliability analysis using the intraclass correlations coefficient (ICC). The Bland-Altman plot was used to measure agreement between the methods for both pre- and post-operative ICV measurements.

RESULTS: The mean ICV (±SD) were 1341.1±122.1ml (manual) and 1344.11±122.6ml (SBI) for the preoperative CT data. The mean ICV (±SD) were 1396.4±132.4ml (manual) and 1400.53±132.1ml (SBI) for the post-operative CT data. No significant difference was found in ICV measurements using the manual and the SBI methods (p=.983 for pre-op, and p=.960 for post-op). The intrarater ICC showed a significant correlation; ICC=1.00. The Bland-Altman plot showed good agreement between the manual and the SBI method.

OBJECTIVES: In this study, we aimed to assess the incremental value of V/Q SPECT/CT over conventional V/Q planar scintigraphy and V/Q SPECT, and to determine if Q only-SPECT/CT without the conventional ventilation component could replace the current imaging protocol in diagnosing pulmonary embolism.

METHODS: We retrospectively assessed 73 patients with suspicion of pulmonary embolism who had undergone/Q planar scintigraphy, V/Q SPECT and V/Q SPECT/CT consecutively. Combination of clinical follow-up, laboratory test results and correlative imaging were used as reference standard. Q-only SPECT/CT datasets were then analysed separately without the V-planar, V-SPECT and V-SPECT/CT datasets.

RESULTS: A total of 66 patients fulfilled our initial inclusion and exclusion criteria, with 23 patients as positive for PE and 43 patients ruled out of having PE based on the reference standard. Sensitivity and specificity for V/P planar scintigraphy, V/Q SPECT, and V/Q SPECT-CT were 86.9% and 39.5%, 91.3% and 55.8%, and 100% and 97.6% respectively. Overall, SPECT/CT resulted in significantly higher diagnostic accuracy than planar and SPECT imaging respectively (p<0.05). Q-only SPECT/CT significantly over diagnosed pulmonary embolism in 12 patients (p<0.05).

Case Description: A 66-year-old male with the right lower extremity weakness was diagnosed with a spinal dural AVF at the L1 level. It was initially treated with open surgery followed by CyberKnife radiosurgery at another institution. Five years later, he presented with a persistent pAVF fistula now involving the T11 level; the major feeder originated on the left at the T7-T8 level (e.g., involving a left-sided "duplicated" anterior spinal artery). Utilizing a three-dimensional (3D) computer tomography (CT) guided approach; he underwent a left-sided posterolateral T10-T12 laminectomy, sufficient to allow for 30-40° of anterior spinal cord rotation. This was performed under neurophysiological monitoring without any significant changes. Surgery included indocyanine green video angiography, temporary feeder clipping, and complete occlusion of the AVF, followed by complete clipping/resection as confirmed on postoperative magnetic resonance imaging.