Incidental Acute Appendicitis on Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Imaging: Radiology From a Different Perspective.

Although Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) is routinely used in oncological imaging, the F-18 fluorodeoxyglucose (18F-FDG) avidity is not tumor-specific. Numerous benign infective and inflammatory processes may also show increased radiotracer activity. Similarly, abnormal 18F-FDG uptake in an inflamed appendix can pose a diagnostic challenge for the interpreter of oncologic 18F-FDG PET/CT. We present the case of an 18-year-old female with classic Hodgkin's lymphoma who had 18F-FDG PET/CT while undergoing chemoradiotherapy. The scan demonstrated a complete metabolic response to treatment. However, there was increased 18F-FDG uptake in the right iliac region, projecting over the appendix, which, if interpreted as a lymphomatous involvement, would have upscaled the treatment response to progressive disease. The patient was called for additional workup, which included an ultrasound abdomen. The scan revealed classic features of acute appendicitis. However, there was no appendicolith or luminal obstruction. Upon additional questioning, the patient mentioned mild intermittent abdominal pain and anorexia eased by pain relievers for the preceding few days. On deep palpation of her abdomen, there was rebound tenderness in the right iliac region. According to the Alvarado score, it was graded 7 points suggesting probable/likely appendicitis. After collective evaluation of the clinical, laboratory, and imaging findings, the appendicular 18F-FDG uptake was deemed secondary to uncomplicated acute appendicitis rather than a lymphomatous lesion. Our patient refused surgery as she did not have severe abdominal pain. She was hemodynamically stable without signs of luminal obstruction. She was non-operatively managed with broad-spectrum antibiotics for six days. The results of the follow-up complete blood counts and ultrasound examination were negative. Our patient was symptom-free and recovering normally at a two-week follow-up appointment. We present a follow-up case of classic Hodgkin's lymphoma with incidental uptake in the appendix, which resembled submucosal lymphomatous cell infiltration of the appendix. Careful scrutiny, clinical correlation, physical examination, blood tests, and additional imaging offered helpful insight and led to the correct, benign diagnosis of the 18F-FDG avid appendix.

Benign uptake of 18F-fluorodeoxyglucose in the gallbladder on positron emission tomography-computed tomography.

18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been established as the indisputable tool in the oncological arena to diagnose, stage/restage, and report treatment response for various tumor malignancies. FDG uptake mostly identifies pathological uptake in oncological scans with the tracer on PET studies; however, benign uptakes are also commonly seen. Reported here is a benign case of increased uptake of the FDG on a PET with computed tomography scan in the gallbladder (GB) of a patient being screened for a known carcinoma breast. The benign accumulation of the tracer is seen in the GB to various degrees and this phenomenon may occur as a result of FDG excretion into the bile. When interpreting clinical PET images, recognition of this phenomenon is important to avoid misdiagnosing physiological GB FDG uptake as pathological so as to avoid misinterpretations of the findings.

The hot embolus of 18F-fluorodeoxyglucose.

Scanning oncological patients with 18F-fluorodeoxyglucose (18F-FDG) for their disease staging, evaluation of treatment response, and monitoring/management has become a standard of care. The use of the radioactive fluorine in the FDG molecule helps establish cell/tissue lines high on glucose consumption and hence metabolically active. Abnormalities are detected on the scan as areas of increased uptake. However, these areas of increased (hot) uptakes do not necessarily translate into a pathological finding. A comprehensive knowledge of the uptakes of the tracer and the potential "pitfalls" that may be associated with them should be known and kept in mind during scan reading. One such pitfall is the "hot clot" or "pulmonary emboli," and we report two such cases encountered at our setup and discuss their causes and how they should be identified and avoided.

Simulation based medical education; teaching normal delivery on intermediate fidelity simulator to medical students.

OBJECTIVE: To assess the effectiveness of medium fidelity simulator in teaching normal vaginal delivery to medical students. METHODS: The quasi-experimental study was conducted at the professional development centre of the Jinnah Sindh Medical University, Karachi, from June to December 2015, and comprised medical students. Third-year medical students were included. They were divided into two groups. Group A was taught normal delivery through traditional PowerPoint and group B through simulator. The instruments used for assessing knowledge were pre-test and post-test, for skills of labour/delivery checklist of performance was used, and perception forms were filled to evaluate workshops/learning environment by students. RESULTS: Of the 76 participants, there were 36(47.4%) in group A and 40(52.6%) in group B. The overall mean age of the participants was 20.86±0.76 years in group B and 20.60±0.95 years in group A (p=0.19). The mean grade point average of the participants was 2.89±0.47 in group A and 2.87±0.48 in group B (p=0.81).Group B performed much better in skill of delivery having a mean score of 8.91±3.20compared to group A which had mean of 5.67±1.84 (p<0.01). CONCLUSIONS: Simulation-based skill learning showed significantly better results.

Bone Turnover Markers for Osteoporosis Status Assessment at Baseline in Postmenopausal Pakistani Females.

OBJECTIVE: To assess bone turnover status in osteopenic and osteoporotic postmenopausal females. STUDY DESIGN: Cross-sectional analytical study. PLACE AND DURATION OF STUDY: The Aga Khan University Hospital, Karachi, from January to December 2013. METHODOLOGY: Across-sectional study was conducted on 203 postmenopausal females undergoing bone mineral density testing (BMD) by DXAscan. Patients with clinical history of any disorder or medications affecting bone turnover were excluded. Bone turnover was assessed with osteocalcin and ß-CTx. Data was analyzed by SPSS version 19. RESULTS: Mean age of the participants was 54 ±4.66 years with a mean BMI of 28.7 ±5.5 kg/m2. Mean ß-CTx (0.28 ±0.24 ng/ml) and osteocalcin (21.5 ±10.6 ng/ml) levels were within the normal reference range. Subjects were grouped into normal (26.6%), osteopenic (44.8%), and osteoporotic (28.6%) based on the t-scores. Serum levels of osteocalcin and ß-CTx between normal, osteopenic, and osteoporotic groups were not significantly different. ß-CTx was negatively and significantly associated with only lumber spine BMD (r = -0.13, p=0.04). Positive association (< 0.0001) was noted between both markers in normal, osteopenic, and osteoporotic females. However, association of these markers with BMD in the 3 groups were not found. Multivariate linear regression showed a positive and significant effect of BMI on BMD (ß= 0.332, p= < 0.0001). ß-CTx had negative but significant effect on BMD (ß= -0.155, p= 0.018) of postmenopausal women. CONCLUSION: Association between baseline levels of BTM and rate of bone loss is variable and site dependent. ß-CTx correlates better with BMD. However, role of osteocalcin in postmenopausal osteoporosis is uncertain and needs further investigation.

Management of Radioactive Spills in Nuclear Medicine; Teaching and Assessing with Objectively Structured Assessment of Technical Skills.

Routine work in nuclear medicine requires the careful elution of radioactivity and its subsequent, storage and handling. Though all effort is maintained to prevent any "spill" of this radioactivity, accidents are bound to happen. The response to this spill is a methodically worked out a plan that is written and adopted as a "standard operating procedure." This protocol is taught to all involved in the area of working as a mock drill/apprenticeship model. No formal evaluation of learning is in place except for the mock drills. The objectively structured assessment of technical skills (OSATS) is a variation on the Objective Structured Clinical Examination, which is a form of workplace based assessment. The OSATS is cited in the Accreditation Council of Graduate Medical Education evaluation toolbox on the website as the most desirable evaluation tool for the patient care topics. It is the objective of this paper is to introduce the "OSATS" for teaching, and assessment of the learning, of the protocol for the management of radioactive spill. As a review of the literature on the subject failed to reveal any such teaching protocol/material/document for this important technical skill, we hope that it may act as a landmark for the development of teaching and assessment of other technical skills also.

99mTc-Nannocolloid Localization of Lymphorenal Fistula Causing Chyluria.

Chyluria is an abnormal condition in which chyle appears in the urine because of a fistulous communication between the lymphatics and the urinary tract. It is not life-threatening and spontaneous regression is reported in 50% of cases. Lymphangiography has been the main imaging modality for localization of the site of fistula, but it is invasive and requires expertise. Lymphoscintigraphy using Tc-99m labelled colloid is a safe, non-invasive, reproducible technique, which bears less radiation exposure. A 67-year-old male presented with 7-month history of chyluria following a spinal surgery. Bilateral lower limb lymphoscintigram revealed sluggish lymph flow in the left lower limb and visualization of tracer in the left kidney consistent with lymphorenal fistula. Subsequent cystography revealed appearance of chylous urine from left ureter. Patient refused surgery.

Isolated tuberculous thyroiditis as solitary thyroid nodule.

Isolated involvement of the thyroid by tuberculosis is very rare as reported in literature. We are presenting a case of isolated tuberculous thyroiditis presented as a solitary thyroid nodule. The patient was treated with anti-tuberculous regimen and he responded well with disappearance of the nodule and normalization of the thyroid scan.

Extra [corrected] pulmonary uptake of Tc-99m-MAA perfusion lung scan as a result of right to left intra cardiac shunt.

Extra pulmonary accumulation of Tc-99m-macroaggregate of albumin (MAA) is rarely seen on perfusion lung scan, and has been reported in less than 4% of a study population of nearly 380 patients. It occurs when the agent bypasses the lungs due to a right to left (R-L) cardiac or pulmonary shunt, when it is shunted to the portal vein before reaching the right atrium and ventricle of the heart, and when the agent is degraded to a submicron particle size. When a pharmaceutical problem is excluded, extra-pulmonary uptake implies unusual hemodynamics with a shunt. A case is reported in which a clinically unsuspected shunt was diagnosed from the lung perfusion scintigraphy.

Sentinel lymph node scintigraphy and radioguided dissection in breast carcinoma: an initial experience at Aga Khan University Hospital.

OBJECTIVE: To evaluate the efficacy of SLN biopsy using imaging and gamma probe in breast cancer and to establish this technique at Aga Khan University Hospital. METHODS: Thirty two patients (mean age 33-76 yrs) with operable breast carcinoma (4 with post-neo adjuvant therapy) with clinically negative axilla were studied. In 28 patients simultaneous axillary dissection was performed. Sentinel lymph nodes (SLN) scintigraphy was performed a day before surgery by injecting Tc-99m labeled nannocolloid sub-dermally in the peri-areolar region in 24 and peri-tumoral in remaining 8. First lymph node (LN) to appear to on the scan was labeled as SLN and marked on the skin. Blue dye was also injected in all patients and blue and hot LN was explored in the axilla using gamma probe. RESULTS: The sentinel LN was identified in 31 patients (96.9% success rate) while in one patient (3.1%) SLN was not visualized on the scan (negative study) and this was a post-neo-adjuvant therapy case. The blue dye successfully localized the sentinel LNs in all 32 cases The gamma probe guided localization was successful in all 31 while in one case with post-neo-adjuvant chemotherapy it failed. In 9 out of 32 (28.1%) cases SLN was positive for metastasis and in 6 out of these 9 (66.6%) the SLN was the only metastatic node. This includes the post-neo-adjuvant case as well. There was no case of skip metastasis, i.e. negative SNL and positive other axillary nodes. In remaining 23 (71.9%) cases SLN was negative for metastasis and in all, axilla was free of disease (NPV of 100%). CONCLUSION: Lymphoscintigraphy with gamma probe guided SNL biopsy is safe, simple and highly reliable technique. With blue dye technique it reduces the blindness of the procedure if performed independently but increases the cost. Finally, this can accurately stage the axilla, possibly allowing axillary dissection to be foregone in patients where the SLN is clear.