Improved Detection of Dry Age-Related Macular Degeneration from Optical Coherence Tomography Images using Adaptive Window Based Feature Extraction and Weighted Ensemble Based Classification Approach

BACKGROUND

Dry Age-related macular degeneration (AMD), which affects the older population, can lead to blindness when left untreated. Preventing vision loss in elderly needs early identification. Dry-AMD diagnosis is still time-consuming and very subjective, depending on the ophthalmologist. Setting up a thorough eye-screening system to find Dry-AMD is a very difficult task.

METHODOLOGY

This study aims to develop a weighted majority voting (WMV) ensemble-based prediction model to diagnose Dry-AMD. The WMV approach combines the predictions from base-classifiers and chooses the class with greatest vote based on assigned weights to each classifier. A novel feature extraction method is used along the retinal pigment epithelium (RPE) layer, with the number of windows calculated for each picture playing an important part in identifying Dry-AMD/normal images using the WMV methodology. Pre-processing using hybrid-median filter followed by scale-invariant feature transform based segmentation of RPE layer and curvature flattening of retina is employed to measure exact thickness of RPE layer.

RESULT

The proposed model is trained on 70% of the OCT image database (OCTID) and evaluated on remaining OCTID and SD-OCT Noor dataset. Model has achieved accuracy of 96.15% and 96.94%, respectively. The suggested algorithm's effectiveness in Dry-AMD identification is demonstrated by comparison with alternative approaches. Even though the suggested model is only trained on the OCTID, it has performed well when tested on additional dataset.

CONCLUSION

The suggested architecture can be used for quick eye-screening for early identification of Dry-AMD. The recommended method may be applied in real-time since it requires fewer complexity and learning-variables.

Inertial active ratchet: Simulation versus theory

We present the inertial active dynamics of an Ornstein-Uhlenbeck particle in a piecewise sawtooth ratchet potential. Using the Langevin simulation and matrix continued fraction method (MCFM), the particle transport, steady-state diffusion, and coherence in transport are investigated in different parameter regimes of the model. Spatial asymmetry is found to be a key criterion for the possibility of directed transport in the ratchet. The MCFM results for net particle current of overdamped dynamics of the particle agree well with the simulation results. The simulated particle trajectories for the inertial dynamics and the corresponding position and velocity distribution functions reveal that the system passes through an activity-induced transition in the transport from the running phase to the locked phase of the dynamics. This is further corroborated by the mean square displacement (MSD) calculations, where the MSD gets suppressed with increase in the persistent duration of activity or self-propulsion in the medium and finally approaches zero for a very large value of self propulsion time. The nonmonotonic behavior of the particle current and Péclet number with self-propulsion time confirms that the particle transport and its coherence can be enhanced or reduced by fine tuning the persistent duration of activity. Moreover, for intermediate ranges of self-propulsion time as well as mass of the particle, even though the particle current shows a pronounced unusual maximum with mass, there is no enhancement in the Péclet number, instead the Péclet number decreases with mass, confirming the degradation of coherence in transport.

Improved detection accuracy of red lesions in retinal fundus images with superlearning approach

BACKGROUND

Diabetic Retinopathy (DR) is a serious consequence of diabetes that can result to permanent vision loss for a person. Diabetes-related vision impairment can be significantly avoided with timely screening and treatment in its initial phase. The earliest and the most noticeable indications on the surface of the retina are micro-aneurysm and haemorrhage, which appear as dark patches. Therefore, the automatic detection of retinopathy begins with the identification of all these dark lesions.

METHOD

In our study, we have developed a clinical knowledge based segmentation built on Early Treatment DR Study (ETDRS). ETDRS is a gold standard for identifying all red lesions using adaptive-thresholding approach followed by different pre-processing steps. The lesions are classified using super-learning approach to improve multi-class detection accuracy. Ensemble based super-learning approach finds optimal weights of base learners by minimizing the cross validated risk-function and it pledges the improved performance compared to base-learners predictions. For multi-class classification, a well informative feature-set based on colour, intensity, shape, size and texture, is developed. In this work, we have handled the data imbalance problem and compared the final accuracy with different synthetic data creation ratios.

RESULT

The suggested approach uses publicly available resources to perform quantitative assessments at lesions-level. The overall accuracy of red lesion segregation is 93.5%, which has increased to 97.88% when data imbalance problem is taken care-off.

CONCLUSION

The results of our system have achieved competitive performance compared with other modern approaches and handling of data imbalance further increases the performance of it.

Inertial active Ornstein-Uhlenbeck particle in the presence of a magnetic field

We consider an inertial active Ornstein-Uhlenbeck particle in an athermal bath. The particle is charged, constrained to move in a two-dimensional harmonic trap, and a magnetic field is applied perpendicular to the plane of motion. The steady-state correlations and the mean-square displacement are studied when the particle is confined as well as when it is set free from the trap. With the help of both numerical simulation and analytical calculations, we observe that inertia plays a crucial role in the dynamics in the presence of a magnetic field. In a highly viscous medium where the inertial effects are negligible, the magnetic field has no influence on the correlated behavior of position as well as velocity. In the time asymptotic limit, the overall displacement of the confined harmonic particle gets enhanced by the presence of a magnetic field and saturates for a stronger magnetic field. On the other hand, when the particle is set free, the overall displacement gets suppressed and approaches zero when the strength of the field is very high. Interestingly, it is seen that in the time asymptotic limit, the confined harmonic particle behaves like a passive particle and becomes independent of the activity, especially in the presence of a very strong magnetic field. Similarly, for a free particle the mean-square displacement in the long time limit becomes independent of activity even for a longer persistence of noise cor- relation in the dynamics.

Orbital magnetism of an active particle in viscoelastic suspension

We consider an active (self-propelling) particle in a viscoelastic fluid. The particle is charged and constrained to move in a two-dimensional harmonic trap. Its dynamics is coupled to a constant magnetic field applied perpendicular to its plane of motion via Lorentz force. Due to the finite activity, the generalized fluctuation-dissipation relation (GFDR) breaks down, driving the system away from equilibrium. While breaking GFDR, we have shown that the system can have finite classical orbital magnetism only when the dynamics of the system contains finite inertia. The orbital magnetic moment has been calculated exactly. Remarkably, we find that when the elastic dissipation timescale of the medium is larger (smaller) than the persistence timescale of the self-propelling particle, it is diamagnetic (paramagnetic). Therefore, for a given strength of the magnetic field, the system undergoes a transition from diamagnetic to paramagnetic state (and vice versa) simply by tuning the timescales of underlying physical processes, such as active fluctuations and viscoelastic dissipation. Interestingly, we also find that the magnetic moment, which vanishes at equilibrium, behaves nonmonotonically with respect to increasing persistence of self-propulsion, which drives the system out of equilibrium.

Accuracy and speed of elongation in a minimal model of DNA replication

Being a dual purpose enzyme, the DNA polymerase is responsible for elongation of the newly formed DNA strand as well as cleaving the erroneous growth in case of a misincorporation. The efficiency of replication depends on the coordination of the polymerization and exonuclease activity of DNA polymerase. Here, we propose and analyze a minimal kinetic model of DNA replication and determine exact expressions for the velocity of elongation and the accuracy of replication. We first analyze the case without exonuclease activity. In that case, accuracy is determined by a kinetic competition between stepping and unbinding, with discrimination between correct and incorrect nucleotides in both transitions. We then include exonuclease activity and ask how different modes of additional discrimination in the exonuclease pathway can improve the accuracy while limiting the detrimental effect of exonuclease on the speed of replication. In this way, we ask how the kinetic parameters of the model have to be set to coordinate the two activities of the enzyme for high accuracy and high speed. The analysis also shows that the design of a replication system does not universally have to follow the speed-accuracy trade-off rule, although it does in the biologically realized parameter range. The accuracy of the process is mainly controlled by the crucial role of stepping after erroneous incorporation, which has impact on both polymerase and exonuclease activities of DNA polymerase.

First report on characterization and pathogenicity study of emerging Lactococcus garvieae infection in farmed rainbow trout, Oncorhynchus mykiss (Walbaum), from India

"Warm water lactococcosis" in farm-reared rainbow trout, Oncorhynchus mykiss (Walbaum) in the northern Himalayan region of India, caused by bacterium Lactococcus garvieae is described in this study. Nine bacterial isolates were recovered from the organs of haemorrhagic septicaemia rainbow trout and were subjected to biochemical and molecular identification. Cell surface characteristics and virulence of the bacterial isolates are also described. All the nine bacterial isolates had homogenous biochemical characteristics and were Gram-positive, short chains forming (two to eight cells long), α-haemolytic, non-motile ovoid cocci. Partial 16S rDNA nucleotide sequence (~1,400 bp) of current isolates shared 99% identities with the 16S rDNA nucleotide sequence of L. garvieae R421, L. garvieae FMA395 and L. garvieae CAU:1730. The identity of the bacterial isolates was further confirmed by PCR amplification of L. garvieae-specific ~1,100 bp fragment. Transmission electron microscopy (TEM) of one representative isolate, L. garvieae RTCLI04, indicates that the isolated strain lacks thick outer capsule and is of KG+ (non-capsulates) phenotype. An intraperitoneal and intramuscular injection (2.6 × 10⁵ CFU ml^-1 ) and also immersion in bacterial suspension @ of 2.6 × 10⁵ CFU ml^-1 to healthy rainbow trout juveniles (body weight: 27.5 ± 3.7 g) with L. garvieae RTCLI04 caused 80%, 60% and 10% cumulative mortality in challenged fish, respectively, within 15 days post-infection. The haemorrhagic septicaemic disease was reproduced experimentally. Histopathological examination of organs of experimentally infected fish revealed extensive degenerative and inflammatory changes in eye, kidney, gill and liver. PCR amplification of several putative virulence genes such as haemolysins, adhesins, LPxTG-containing surface proteins and adhesins cluster confirms the virulence of our Indian L. garvieae isolates. To the best of our knowledge, we are reporting for the first time that L. garvieae is associated with fatal haemorrhagic septicaemia in farmed rainbow trout in India.

Recombinant activated factor VII for diffuse alveolar hemorrhage in microscopic polyangiitis

Diffuse alveolar hemorrhage is a serious complication of the small vessel vasculitis syndromes and carries a high mortality. Recombinant activated factor VII (rFVIIa) is a powerful hemostatic agent developed for treatment of bleeding in patients with hemophilia and antibodies to factors VIII or IX. It has been used increasingly in life-threatening hemorrhage in a variety of other settings in which conventional medical or surgical therapy is unsuccessful. We report the successful use of rFVIIa for massive pulmonary hemorrhage in a patient of microscopic polyangiitis, which was later complicated by thrombotic microangiopathy and posterior reversible encephalopathy syndrome.

Family association between immune parameters and resistance to Aeromonas hydrophila infection in the Indian major carp, Labeo rohita

Seven innate immune parameters were investigated in 64 full-sib families (the offspring of 64 sires and 45 dams) from two year-classes of farmed rohu carp (Labeo rohita). Survival rates were also available from Aeromonas hydrophila infection (aeromoniasis) recorded in controlled challenge tests on a different sample of individuals from the same families. Due to strong confounding between the animal additive genetic effect and the family effects (common environmental+non-additive genetic), reliable additive (co)variance components and hence heritabilities and genetic correlations could not be obtained for the investigated parameters. Therefore, estimates of the association of challenge test survival with the studied immune parameters were obtained as product moment correlations between family least square means. These correlations revealed statistically significant (p<0.05) negative correlations of survival with bacterial agglutination titre (-0.48), serum haemolysin titre (-0.29) and haemagglutination titre (-0.34); and significant positive correlation with ceruloplasmin level (0.51). The correlations of survival to aeromoniasis with myeloperoxidase activity, superoxide production and lysozyme activity were found to be not significantly different from zero (p>0.05). Assuming that the negatively correlated candidate traits are not favourable as indirect selection criteria, the results suggest that ceruloplasmin level could potentially be a marker for resistance to aeromoniasis in rohu. The use of this immune parameter as an indirect selection criterion for increased resistance to aeromoniasis in rohu will, however, require that the parameter shows significant additive genetic variation and a significant genetic correlation with survival. Further studies are therefore needed to obtain a reliable heritability estimate for ceruloplasmin and its genetic correlation with survival from aeromoniasis.

Preoperative ultrasound-guided fine-needle aspiration cytology for axillary staging in breast carcinoma

Axillary lymph node (ALN) status is considered to be the single most important prognostic indicator in patients with breast cancer. It can be assessed by various radiological, pathological and surgical techniques, the most accurate being histological examination of lymph nodes after axillary lymph node dissection (ALND). This prospective study was conducted to assess the feasibility and diagnostic accuracy of preoperative ultrasound (US) and ultrasound-guided fine-needle aspiration cytology (USG-FNAC) of ALN in patients with breast cancer. Thirty patients with FNAC-proven breast cancer, planned for definitive surgery with axillary clearance, were included in this study. Ultrasonographic evaluation of the axillae of these patients was conducted for alterations in size, shape, contour and cortical morphology of lymph nodes that could reflect presence of underlying metastases. Ultrasound-guided fine-needle aspiration cytology of the ALN was done in 24 of these patients. These findings were evaluated, with the ALN status determined by histological examination after ALND. Out of the 30 patients, eight had T(1), 16 had T(2), five had T(3), and one had T(4) lesions. Ultrasound evaluation of the ALN had a sensitivity of 86.3%, a specificity of 41.6%, a positive predictive value of 79%, a negative predictive value of 50% and a diagnostic accuracy of 73.3%. Sensitivity of USG-FNAC was 78.95%, specificity was 100%, positive predictive value was 100%, negative predictive value was 55.56% and diagnostic accuracy was 83.33%. Our study concludes that preoperative USG-FNAC of ALN is a simple, minimally invasive, easily available and reliable technique for the initial determination of ALN status in patients with breast cancer. Those who are USG-FNAC positive can be directed towards ALND straight away, and only those who are USG-FNAC negative should be considered for sentinel lymph node biopsy. This will save considerable operating time, especially where facilities for sentinel lymph node biopsy (costly dye, gamma camera, nuclear medicine facilities) are restricted or not available.

Is the routine drainage after surgery for thyroid necessary? A prospective randomized clinical study [ISRCTN63623153]

Background

Drains are usually left after thyroid surgery to prevent formation of hematoma and seroma in the thyroid bed. This is done to reduce complications and hospital stay. Objective evaluation of the amount collected in the thyroid bed by ultrasonography (USG) can help in assessing the role of drains.

Methods

A randomized prospective control study was conducted on 94 patients undergoing 102 thyroid surgeries, over a period of fifteen months. Patients included in the study were randomly allocated to drain and non-drain group on the basis of computer generated random number table. The surgeon was informed of the group just before the closure of the wound Postoperatively USG neck was done on first and seventh postoperative day by the same ultrasonologist each time. Any swelling, change in voice, tetany and tingling sensation were also recorded. The data was analyzed using two-sample t-test for calculating unequal variance.

Results

Both groups were evenly balanced according to age, sex, and size of tumor, type of procedure performed and histopathological diagnosis. There was no significant difference in collection of thyroid bed assessed by USG on D1 & D7 in the two groups (p = 0.313) but the hospital stay was significantly reduced in the non-drain group (p = 0.007). One patient in the drain group required needle aspiration for collection in thyroid bed. No patient in either group required re-operation for bleeding or haematoma.

Conclusion

Routine drainage of thyroid bed following thyroid surgery may not be necessary. Not draining the wound results in lesser morbidity and decreased hospital stay.

Differentiation of Malignant and Benign Solitary Thyroid Nodules Using 30- and 120-Minute Tc-99m MIBI Scans

Technetium-99m methoxy isobutylisonitrate (MIBI) has been found to be taken up by various tumors, including thyroid cancer. We prospectively evaluated 77 patients with cold thyroid solitary nodules on Tc-99m pertechnetate scintigraphy to evaluate the diagnostic value of Tc-99m MIBI scintigraphy. The aim of this study was to find out if thyroid nodules can be characterized on the basis of retention of MIBI and whether preoperative evaluation of malignancy is possible using this method. Single injection, dual-phase (30 and 120 minutes) thyroid scintigraphy using Tc-99m MIBI was performed in all these patients. In the following days and weeks, all patients underwent surgery. Using the 120/30-minute thyroid lesion to background radiouptake ratio (RUR), malignant and benign thyroid nodules could be separated with a sensitivity, specificity, and positive predictive value of 84.4%, 95.45%, and 93.33%, respectively. The mean RUR for malignant thyroid lesions was found to be 1.57+/-0.32, whereas for benign lesions, the ratio was significantly lower, 0.32+/-0.19. In conclusion, fine needle aspiration cytology along with the 120/30 minutes Tc-99m MIBI scintigraphy ratio appears to be useful in the preoperative assessment of solitary thyroid nodules.

Familial aggregation of autoimmune thyroiditis in first-degree relatives of patients with juvenile autoimmune thyroid disease

Several studies have shown aggregation of autoimmune thyroiditis in families by estimation of thyroid antibodies. However, the prevalence by concurrent estimation with fine-needle aspiration cytology (FNAC) and thyroid antibodies has not been previously reported. We therefore studied 222 first-degree relatives (group 1) of 71 index cases diagnosed as lymphocytic thyroiditis on FNAC and 81 family members (group 2) of 23 goitrous children diagnosed as colloid goiter on FNAC for comparison. Successful FNAC conducted in 122 group 1 subjects revealed lymphocytic thyroiditis in 51 (42%), whereas lymphocytic thyroiditis was diagnosed in only 5 goitrous subjects (13%) in group 2. Among group 1 subjects with FNAC-proven lymphocytic thyroiditis, antithyroid peroxidase (TPO) antibodies were found in 35 (67%), while in anti-TPO antibody positive goitrous relatives of group 1, lymphocytic thyroiditis was found in 36 (78%). Eight new cases of overt hypothyroidism and 45 new cases of subclinical hypothyroidism were diagnosed among group 1 subjects. Our study suggests: (1). familial clustering of autoimmune thyroiditis; (2). if only FNAC or thyroid antibodies is used for diagnosis of autoimmune thyroiditis in children, 22%-33% of cases are likely to be missed; and (3). serum thyrotropin (TSH) should be offered to all first-degree relatives of patients with juvenile autoimmune thyroiditis.

Hemiagenesis of the Thyroid Associated with Chronic Lymphocytic Thyroiditis

The authors report a case of hemiagenesis of the left thyroid lobe indicated on Tc-99m pertechnetate scan and later confirmed on ultrasonography. The patient was clinically hypothyroid with a right-sided goiter. The cytopathologic diagnosis was made by fine-needle aspiration cytologic analysis, which indicated chronic lymphocytic thyroiditis in the right lobe of the thyroid gland. Later the patient's condition was stabilized with thyroxine replacement therapy. The association of hemiagenesis of the thyroid with chronic lymphocytic thyroiditis has not been reported in the literature.

Serous fluid leakage following modified Blalock-Taussig operation using PTFE grafts

BACKGROUND

Serous fluid leakage is an unusual but often devastating complication following the placement of a modified Blalock-Taussig shunt using a polytetrafluoroethylene graft.

METHOD AND RESULTS

Between September 1994 and September 1999, out of 268 patients undergoing a modified Blalock-Taussig shunt using polytetrafluoroethylene grafts, 10 developed massive pleural effusion or seroma due to a leak from the surface of the shunt. The age of the patients ranged from 9 days to 7 years. There were 7 males and 3 females. Nine patients presented with respiratory distress between 2 and 12 weeks of shunt surgery and one presented with sudden cardiac arrest. The shunt was patent in all the patients. Initial management was conservative. i.e. by pharmacological means and tube thoracostomy. Reoperation was undertaken in 9 patients when conservative treatment failed. All patients survived except one who had a cardiac arrest before any intervention could be carried out.

CONCLUSIONS

Patients with serous effusion have significant morbidity and mortality and often require reoperation. The initial management remains conservative but, if unsuccessful, re-exploration can be undertaken as it proved to be uniformly successful in our experience.

Fine needle aspiration cytology, histology and MIB-1 proliferative index in a case of dyshormonogenetic goitre

The fine needle aspiration (FNA) cytologic findings along with histology and MIB-1 proliferative index in a case of dyshormonogenetic goitre is presented. A 12-year old female child from non-endemic zone presented with a isotopically cold solitary thyroid nodule with a history of goitre being present since birth. Past history of any neck irradiation or maternal ingestion of any goitrogen during the antenatal period and family history of goitre were negative. FNA cytology revealed an extremely cellular preparation with predominantly microfollicular pattern without colloid. Nuclei were round to oval, slightly enlarged with evenly distributed chromatin and inconspicuous nucleoli. Larger tissue fragments also showed foci of solid cell groups with nuclear crowding, overlapping and loss of polarity in addition to the prevalent microfollicular pattern. Occasional tissue fragments showed solid groups of trapped follicular epithelial cells in the matrix of fibrocollagenous tissue. Histology showed an intensely hyperplastic follicular cells with nodule formation, irregular fibrosis, pseudo capsular or vascular wall invasion mimicking malignancy. Immunohistochemistry for calcitonin was negative but thyroglobulin was positive. MIB-1 (Ki-67) proliferation index varied from 0.05 to 0.26 (mean 0.13) in the hyperplastic nodules versus 0.9 to 2.1 (mean 1.34) in the hyperplastic solid microfoci scattered amidst the grossly normal appearing thyroid tissue. The possible cytologic diagnostic pitfalls in favor of follicular neoplasm is discussed.

Surgical myocardial revascularization without cardiopulmonary bypass

BACKGROUND

Though coronary artery bypass grafting (CABG) without cardiopulmonary bypass is being performed with increasing frequency, in the absence of adequate angiographic follow-up, safety, reproducibility, and efficacy of the procedure remain doubtful. In this prospective study, we report the results obtained by 100% angiographic follow-up of 96 consecutive patients.

METHODS

A total of 96 patients (age range 33 to 76 years) underwent CABG without cardiopulmonary bypass. Single vessel disease was present in 46 (47.9%) patients, double vessel disease in 31 (32.3%), and triple vessel disease in 19 (19.8%) patients. All patients were operated through a standard midsternotomy and an optimal combination of pharmacological and mechanical methods were used to restrict cardiac movements during anastomosis. All patients underwent coronary angiography before discharge from the hospital.

RESULTS

A total of 160 grafts were placed (range 1 to 4 grafts per patient, average 1.7+/-0.3 grafts per patient). A single graft was placed in 46 patients, double grafts in 38, triple grafts in 10, and quadruple grafts in 2 patients. Various grafts included pedicled left internal mammary artery (LIMA) (n = 95), free LIMA (n = 1), right internal mammary artery (n = 14), radial artery (n = 24), right gastroepiploic artery (n = 5), and saphenous vein grafts (n = 21). Operative mortality was 1.0% (1 of 96). Two patients required reoperation for excessive bleeding. Mean hospital stay was 5.7+/-1.2 days. Overall angiographic patency was 95.0% with LIMA patency of 97.9% (93 of 95). One patient with block in midsegment of LIMA was reoperated using cardiopulmonary bypass. Follow-up ranged from 4 to 17 months (mean 8.2+/-3.1 months). Two patients (one with narrowed LIMA to left anterior descending artery anastomosis, and one with patent anastomosis) had residual angina.

CONCLUSIONS

Coronary artery bypass grafting without cardiopulmonary bypass is a reproducible, effective, and safe option in selected group of patients. A conscientious approach in patient selection and route of operation is required.

Role of radionuclide perfusion study in cold solitary thyroid nodule for diagnosis of malignancy: a complimentary diagnostic modality to fine needle aspiration cytology

One hundred and forty eight subjects with euthyroid solitary thyroid nodules (STN) were taken up for radionuclide perfusion study. They were found to have a cold STN on 99mTc thyroid static scan. All had fine needle aspiration cytology (FNAC), and except for subjects with chronic lymphocytic thyroiditis, were subjected to surgery for tissue diagnosis by histopathology. The diagnostic findings in these patients of solitary thyroid nodules were correlated with the histopathology. Radionuclide perfusion study is considered useful to differentiate benign from malignant cold thyroid solitary nodules with high degree of sensitivity (95%) and specificity (87.9%).

Hyalinizing trabecular adenoma--a case report with FNAC histologic, MIB-1 proliferative index and immunohistochemical findings

Hyalinizing trabecular adenoma is a recently described benign thyroid tumor, almost exclusively occurring in females. The morphological features of this entity overlap with both papillary and medullary carcinoma to varying extent. This, in turn, creates a situation of serious diagnostic pitfall particularly for a false positive diagnosis of papillary carcinoma in fine needle aspiration (FNA) cytology. False consideration of medullary carcinoma is also possible by the unwary especially if staining for Congo red and/or immunostaining for calcitonin is not resorted to. At histologic level, the distinctive architectural pattern is however of great help and thus poses a much lesser danger of misdiagnosis. We relate here our experience in a recently encountered case of hyalinizing trabecular adenoma and describe detailed FNA cytologic and histologic findings along with immunohistochemical profile using a panel of eight monoclonal antibodies. The tumor proliferative potential has also been assessed using MIB-1 (Ki-67) immunostaining. The various pros and cons of diagnostic pitfalls are discussed.

Fine-needle aspiration cytology in a case of isolated involvement of thyroid with Langerhans cell histiocytosis

We present an unusual case of isolated thyroid involvement with Langerhans cell histiocytosis (LCH), diagnosed presumptively by fine-needle aspiration (FNA) cytology and subsequently confirmed by immunohistochemistry in a 13-yr-old boy. The cytologic findings include high cellularity in a hemorrhagic background, the presence of characteristic mononucleated and multinucleated Langerhans cells with prominent nuclear grooves, and abundant foamy cytoplasm in a background of mixed eosinophilic and aggregates of benign thyroid follicular cells. Further diagnostic confirmation was obtained by positive S-100 protein immunohistochemistry of the Langerhans histiocytes on paraffin-embedded sections of open thyroid biopsy of the prominently enlarged left lobe. We present the complete clinicopathologic features of this case, along with ultrasound, computerized axial tomographic, and technetium-99 scan findings. We also discuss possible differential diagnostic consideration in light of a review of the literature and the role of FNA cytologic diagnosis in such a rare yet cytomorphologically characteristic case.

Fine needle aspiration cytology of amyloid goiter. A report of four cases

BACKGROUND

Amyloid goiter is a very rare clinical entity. It can be confused easily with a neoplastic goiter both clinically and cytologically.

CASES

In four cases of amyloid goiter the diagnosis was established preoperatively by fine needle aspiration cytology. Abundant violet to pink amorphous material with staining characteristics of amyloid was obtained in all cases. This material was morphologically distinct from colloid. Abdominal fat aspiration was done in all four cases. Two of the four abdominal fat aspirates were positive for amyloid.

CONCLUSION

Attention to the morphology of cells accompanying amyloid allows exclusion of medullary thyroid carcinoma, thereby avoiding unnecessary surgery. Moreover, aspirates from the abdominal pad of fat and the thyroid and salivary glands, when enlarged, are useful in the workup of suspected amyloidosis, especially since it is a safe, easily performed procedure.