Rhnull phenotype in an Indian patient due to a novel c.1138 + 2 t > a mutation in the RHAG gene.

BACKGROUND: The Rh system is an extremely important RBC antigen system with over 50 antigens, 5 of which (D, C, E, c and e) are considered most clinically significant. The rare Rhnull phenotype can result from mutations in the RHD and RHCE genes or the RHAG gene that affects their expression. This is a case report of the second type. CASE REPORT: This case reports a multiparous lady who had to be evaluated for a panreactive antibody. The discrepancy was first identified at the centre she reported to. A thorough immunohematological workup was performed at a second reference laboratory. Suspecting Rhnull phenotype, a third referral (molecular typing) was requested at International Blood Group Reference Laboratory (IBGRL), Bristol. RESULTS: A novel RHAG null allele (c.1138+2t>a), causing a Rhnull phenotype was identified. The antibody was most likely an anti-Rh 29 antibody. CONCLUSION: The novel c.1138+2 t > a mutation in the RHAG gene causing the Rhnull phenotype and development of a pan reacting antibody(ies) made the patient's pregnancy challenging. Confirmation of the diagnosis, an important step in her management, required use of both serological immunohematology and molecular techniques.

Induction of epithelial-mesenchymal transition in thyroid follicular cells is associated with cell adhesion alterations and low-dose hyper-radiosensitivity.

BACKGROUND: Epithelial-mesenchymal transition (EMT) is associated with altered cellular adhesion. We previously demonstrated that cellular adhesion influences Low-dose Hyper-Radiosensitivity (HRS) in a variety of tumor cells. However, the relationship of low-dose HRS with the phenotypic plasticity incurred by EMT during the neoplastic transformation remains to be elucidated. OBJECTIVE: To investigate whether acquisition of EMT phenotype during progressive neoplastic transformation may affect low-dose radiation sensitivity. METHODS: Primary thyroid cells obtained from a human cystic thyroid nodule were first subjected to nutritional stress. This yielded immortalized INM-Thy1 cell strain, which was further treated with either multiple γ-radiation fractions (1.5 Gy each) or repetitive cycles of 3-methylcholanthrene and phorbol-12-myristate-13-acetate, yielding two progressive transformants, viz., INM-Thy1R and INM-Thy1C. Morphological alterations, chromosomal double-minutes, cell adhesion proteins, anchorage dependency, tumorigenicity in nude mice and cellular radiosensitivity were studied in these strains. RESULTS: Both transformants (INM-Thy1R, INM-Thy1C) displayed progressive tumorigenic features, viz., soft agar colony growth and solid tumor growth in nude mice, coupled with features of epithelial-mesenchymal transition and activated Wnt pathway. Incidentally, the chemical-induced transformant (INM-Thy1C) displayed a prominent HRS (αs/αr = 29.35) which remained unaffected at high cell density. However, the parental (INM-Thy1) cell line as well as radiation-induced transformant (INM-Thy1R) failed to show this hypersensitivity. CONCLUSION: The study shows that induction of EMT in thyroid follicular cells may accompany increased susceptibility to low-dose ionizing radiation, which was attenuated by adaptive resistance acquired during radiation-induced transformation.

Esculetin releases maturation arrest and induces terminal differentiation in leukemic blast cells by altering the Wnt signaling axes.

BACKGROUND: The "Differentiation therapy" has been emerging as a promising and more effective strategy against acute leukemia relapses. OBJECTIVE: In extension to the revolutionising therapeutic outcomes of All Trans Retinoic Acid (ATRA) to induce terminal differentiation of Acute Promyelocytic Leukemic (APL) blast cells, we decipher the potential effect of a natural compound "Esculetin" to serve as a differentiating agent in Acute Myeloid Leukemia (AML). Underlaying role of Wnt signaling pathways in esculetin mediated blast cell differentiation was also evaluated. METHODS: Human acute myeloid leukemic cells (Kasumi-1) with t(8;21/AML-ETO) translocation were used as a model system. Growth inhibitory and cytotoxic activity of esculetin were analysed using growth kinetics and MTT assay. Morphological alterations, cell scatter characteristics, NBT reduction assay and cell surface marker expression patterns were analysed to detect terminally differentiated phenotypes. We employed RT2profiler PCR array system for the analysis of transcriptome profile of Wnt signaling components. Calcium inhibitors (TMB8 and Amlodipine) and Transforming growth factor beta (TGF-ß) were used to modulate the Wnt signaling axes. RESULTS: We illustrate cytotoxic as well as blast cell differentiation potential of esculetin on Kasumi-1 cells. Morphological alterations akin to neutrophilic differentiation as well as the corresponding acquisition of myeloid lineage markers indicate terminal differentiation potential of esculetin in leukemic blast cells. Exposure to esculetin also resulted in downregulation of canonical Wnt axis while upto ~ 21 fold upregulation of non-canonical axis associated genes. CONCLUSIONS: Our study highlights the importance of selective use of calcium pools as well as "axis shift" of the canonical to non-canonical Wnt signaling upon esculetin treatment which might abrogate the inherent proliferation to release maturation arrest and induce the differentiation in leukemic blast cells. The current findings provide further therapeutic interventions to consider esculetin as a potent differentiating agent to counteract AML relapses.

Early outcomes after the on pump bidirectional Glenn procedure: A single center experience.

OBJECTIVE: Bidirectional Glenn procedure is a staged palliative procedure for patients with the univentricular hearts or complex congenital heart disease. We in our study, attempted to evaluate the preoperative characteristics, operative data and the early postoperative outcomes in the patients who underwent Bidirectional Glenn procedure at our center. METHODS: In our single center retrospective experience, 115 patients underwent Bidirectional Glenn procedure from January 2015 to December 2019. RESULTS: The mean age of the patients was 6.55 ± 6.5 years (range from 9 months to 48 years) and a median of 5 years. The most common anatomic diagnosis was double outlet right ventricle (n = 49, 42.6%). The primary diagnosis and the additional cardiac anamolies were not associated with the adverse outcomes. The increased cardiopulmonary bypass and operative time affect the postoperative outcomes. The median oxygen saturation in the patients postoperatively was 82%. The median postoperative stay was 8 days. The early postoperative complications were seen in 29 patients (25.2%). There were 12 early deaths (10.4%) in our study. The late age of presentation and poor preoperative nutrition, increased the risk of the postoperative morbidity and mortality. CONCLUSION: Bidirectional Glenn procedure is an effective procedure to improve efficacy of the gas exchange and reduce volume overload on the single ventricle at early as well as late stages. However, the late age of presentation increases the risk of the postoperative outcomes.

In vitro mesenchymal-epithelial transition in NIH3T3 fibroblasts results in onset of low-dose radiation hypersensitivity coupled with attenuated connexin-43 response.

BACKGROUND: Mesenchymal-to-epithelial transition (MET) is associated with altered cell adhesion patterns. Independent studies showed that cellular adhesion regulates low-dose hyper-radiosensitivity (HRS), a phenomenon reported widely in tumour cells. Therefore, present study aimed to investigate whether MET and associated cellular adhesion alterations affect cellular radiosensitivity. METHODS: We established multiple stages of MET by in vitro transformation of NIH3T3 mouse embryonic fibroblasts. Nutritional deprivation followed by repetitive treatment cycles of 3-methylcholanthrene and phorbol-12-myristate-13-acetate with frequent isolation of foci established three progressive strains (NIH3T3.1, NIH3T3x3, NIH3T3x8x3) depicting MET, and one strain (NIH3T3x12) with partial reversion. Alterations in morphology, cell adhesion properties, expression/intracellular localization of cell adhesion proteins, microRNA expression and cellular radiosensitivity were studied in these stably transformed cell strains. RESULTS: All four transformants had increased proliferation rate, saturation density, bipolarity, E-cadherin expression; coupled with reduced cell size/spreading, pseudopodia/migration, and fibroblast marker protein and vimentin. The most aggressive trans-differentiated (phenotypically epithelial) cell strain, NIH3T3x8x3 acquired ~30% higher growth potential associated with more than two-fold reduction in cell size and migration. These phenotypic changes accompanied ~40% reduction in endogenous or radiation-induced connexin-43 expression/mitochondrial translocation. Incidentally, all three progressive strains displayed prominent HRS (αs/αr: 7.95-37.29) whereas parental (NIH3T3) and reverting (NIH3T3x12) strains lacked HRS and had distinct radiation-induced Cx43 translocation into mitochondria. CONCLUSION: Our study shows that trans-differentiating fibroblasts progressively acquiring epithelial features during MET process, display low-dose hyper-radiosensitivity associated with altered Cx43 behaviour. GENERAL SIGNIFICANCE: This study demonstrates that MET progression triggers low-dose hyper-radiosensitivity in trans-differentiating cells, which has significant therapeutic implications.

Bronchial artery embolization in treatment of hemoptysis: Treatment efficacy and complications at a tertiary care chest centre.

BACKGROUND: Hemoptysis is one of the most alarming condition to both the patients suffering from it and the treating physicians. It is caused due to varied etiologies. One of the emergent and at times life-saving treatment option is by minimally invasive interventional radiological technique of Bronchial Atery Embolization (BAE). The authors aimed to carry out a retrospective analysis of short term efficacy and safety of all patients treated by this technique at a tertiary care thoracic centre. METHODS: A total of 52 patients were included in the study who had a median follow up of 35 days. All these patients were referred for hemoptysis, intractable hemoptysis not controlled by conservative management or massive hemoptysis. An analysis of the underlying etiology, immediate and short term outcomes and complications was made. RESULTS: The study showed Tuberculosis and its sequel (bronchiectasis and chronic fibrotic changes) as the commonest etiology (65%). The BAE showed high short term efficacy (92%) in stopping the hemoptysis with a relatively low complication rate especially of major complications such as spinal cord ischemia (1.9%). The study strengthens the limited Indian data available on the subject and based on its outcome, BAE should be tried in all patients presenting with uncontrollable or massive hemoptysis not getting relief by conservative management alone. CONCLUSION: BAE is a very effective procedure with very less complications for management of massive or uncontrollable hemoptysis.

Pericardial Effusion with Cardiac Tamponade as a form of presentation of Primary Hypothyroidism.

Hypothyroidism is a rare cause of pericardial effusion (PE). Pericardial effusion secondary to hypothyroidism remains a diagnostic challenge for clinicians because of its inconsistency between symptoms and amount of pericardial effusion. We report an atypical case that presented with ascites and was diagnosed to have cardiac tamponade secondary to primary hypothyroidism. Besides repeated pericardiocentesis she eventually required surgical management and optimization of medical therapy to manage the massive pericardial effusion.

Pilot study: effect of age on visual acuity with defocus and astigmatism.

PURPOSE: To investigate how distance visual acuity in the presence of defocus and astigmatism is affected by age and whether aberration properties of young and older eyes can explain any differences. METHODS: Participants were 12 young adults (mean [±SD] age, 23 [±2] years) and 10 older adults (mean [±SD] age, 57 [±4] years). Cyclopleged right eyes were used with 4-mm effective pupil sizes. Thirteen blur conditions were used by adding five spherical lens conditions (-1.00 diopters [D], -0.50 D, plano/0.00 D, +0.50 D, and +1.00 D) and adding two cross-cylindrical lenses (+0.50 DS/-1.00 DC and +1.00 D/-2.00 DC, or 0.50 D and 1.00 D astigmatism) at four negative cylinder axes (45, 90, 135, and 180 degrees). Targets were single lines of high-contrast letters based on the Bailey-Lovie chart. Successively smaller lines were read until a participant could no longer read any of the letters correctly. Aberrations were measured with a COAS-HD Hartmann-Shack aberrometer. RESULTS: There were no significant differences between the two age groups. We estimated that 70 to 80 participants per group would be needed to show significant effects of the trend of greater visual acuity loss for the young group. Visual acuity loss for astigmatism was twice that for defocus of the same magnitude of blur strength (0.33 logMAR [logarithm of the minimum angle of resolution]/D compared with 0.18 logMAR/D), contrary to the geometric prediction of similar loss. CONCLUSIONS: Any age-related differences in visual acuity in the presence of defocus and astigmatism were swamped by interparticipant variation.

Visual field coordinates of pupillary circular axis and optical axis.

PURPOSE: We term the visual field position from which the pupil appears most nearly circular as the pupillary circular axis (PCAx). The aim was to determine and compare the horizontal and vertical coordinates of the PCAx and optical axis from pupil shape and refraction information for only the horizontal meridian of the visual field. METHODS: The PCAx was determined from the changes with visual field angle in the ellipticity and orientation of pupil images out to ±90 degrees from fixation along the horizontal meridian for the right eyes of 30 people. This axis was compared with the optical axis determined from the changes in the astigmatic components of the refractions for field angles out to ±35 degrees in the same meridian. RESULTS: The mean estimated horizontal and vertical field coordinates of the PCAx were -5.3 (±1.9) and -3.2 (±1.5) degrees compared with -4.8 (±5.1) and -1.5 (±3.4) degrees for the optical axis, respectively. The vertical coordinates of the two axes were just significantly different (p = 0.03), but there was no significant correlation between them. Only the horizontal coordinate of the PCAx was significantly related to the refraction in the group. CONCLUSIONS: On average, the PCAx is displaced from the line-of-sight by about the same angle as the optical axis, but there is more intersubject variation in the position of the optical axis. When modeling the optical performance of the eye, it appears reasonable to assume that the pupil is circular when viewed along the line-of-sight.

Identification and clinicopathological analysis of potential p73-regulated biomarkers in colorectal cancer via integrative bioinformatics.

This study aims to decipher crucial biomarkers regulated by p73 for the early detection of colorectal cancer (CRC) by employing a combination of integrative bioinformatics and expression profiling techniques. The transcriptome profile of HCT116 cell line p53 - / - p73 + / + and p53 - / - p73 knockdown was performed to identify differentially expressed genes (DEGs). This was corroborated with three CRC tissue expression datasets available in Gene Expression Omnibus. Further analysis involved KEGG and Gene ontology to elucidate the functional roles of DEGs. The protein-protein interaction (PPI) network was constructed using Cytoscape to identify hub genes. Kaplan-Meier (KM) plots along with GEPIA and UALCAN database analysis provided the insights into the prognostic and diagnostic significance of these hub genes. Machine/deep learning algorithms were employed to perform TNM-stage classification. Transcriptome profiling revealed 1289 upregulated and 1897 downregulated genes. When intersected with employed CRC datasets, 284 DEGs were obtained. Comprehensive analysis using gene ontology and KEGG revealed enrichment of the DEGs in metabolic process, fatty acid biosynthesis, etc. The PPI network constructed using these 284 genes assisted in identifying 20 hub genes. Kaplan-Meier, GEPIA, and UALCAN analyses uncovered the clinicopathological relevance of these hub genes. Conclusively, the deep learning model achieved TNM-stage classification accuracy of 0.78 and 0.75 using 284 DEGs and 20 hub genes, respectively. The study represents a pioneer endeavor amalgamating transcriptomics, publicly available tissue datasets, and machine learning to unveil key CRC-associated genes. These genes are found relevant regarding the patients' prognosis and diagnosis. The unveiled biomarkers exhibit robustness in TNM-stage prediction, thereby laying the foundation for future clinical applications and therapeutic interventions in CRC management.

Clinicodemographic profile, management, and treatment outcomes in advanced retinoblastoma at a tertiary care center in North India.

PURPOSE: The study was undertaken to look into the clinicodemographic profile, management, and clinical outcomes of advanced retinoblastoma at a tertiary care center. METHODS: A prospective cohort study was conducted from Jan 2019 to Dec 2022. Forty-two patients of intraocular advanced retinoblastoma were assessed. The treatment protocol was formulated based on size, extension of tumor, and laterality. Primary outcome measure was response to the treatment in terms of regression of tumor and seeds and no evidence of recurrence after 12 month in enucleated eyes. Secondary outcome measures were complications like implant exposure, metastasis, and death associated with each treatment modality. RESULTS: The mean age of the study group was 13 months. The most common presentation was leukocoria with diminished vision. Most of the patients had group E retinoblastoma ( n = 40, 95%) as per the International Classification of Retinoblastoma. In 12 patients with group E retinoblastoma, primary enucleation was performed and in six patients, secondary enucleation was done, in which initially, globe salvage treatment was tried. In 30 patients, globe salvage treatment was attempted and we could manage to save 23 eyes. The most common treatment modality was intra-arterial chemotherapy using a triple-drug regimen. One patient developed intracranial spread and died due to systemic metastasis during the follow-up period. CONCLUSION: The current study showed that globe salvage is possible in advanced retinoblastoma if appropriate therapy is instituted depending upon the extent of the tumor and availability of latest treatment modalities. Intra-arterial chemotherapy using triple drugs can be offered as a first-line therapy in advanced unilateral retinoblastoma as it has been found to be very effective in the present study.

Peripheral refraction patterns out to large field angles.

PURPOSE: To investigate hyperopic shifts and the oblique (or 45-degree/135-degree) component of astigmatism at large angles in the horizontal visual field using the Hartmann-Shack technique. METHODS: The adult participants consisted of 6 hypermetropes, 13 emmetropes and 11 myopes. Measurements were made with a modified COAS-HD Hartmann-Shack aberrometer across ± 60 degrees along the horizontal visual field in 5-degree steps. Eyes were dilated with 1% cyclopentolate. Peripheral refraction was estimated as mean spherical (or spherical equivalent) refraction, with/against the rule of astigmatism and oblique astigmatism components, and as horizontal and vertical refraction components based on 3-mm major diameter elliptical pupils. RESULTS: Thirty percent of eyes showed a pattern that was a combination of type IV and type I patterns of Rempt et al. (Rempt F, Hoogerheide J, Hoogenboom WP. Peripheral retinoscopy and the skiagram. Ophthalmologica 1971;162:1-10), which shows the characteristics of type IV (relative hypermetropia along the vertical meridian and relative myopia along the horizontal meridian) out to an angle of between 40 and 50 degrees before behaving like type I (both meridians show relative hypermetropia). We classified this pattern as type IV/I. Seven of 13 emmetropes had this pattern. As a group, there was no significant variation of the oblique component of astigmatism with angle, but about one-half of the eyes showed significant positive slopes (more positive or less negative values in the nasal field than in the temporal field) and one-fourth showed significant negative slopes. CONCLUSIONS: It is often considered that a pattern of relative peripheral hypermetropia predisposes to the development of myopia. In this context, the finding of a considerable portion of emmetropes with the IV/I pattern suggests that it is unlikely that refraction at visual field angles beyond 40 degrees from fixation contributes to myopia development.

Visual performance with lenses correcting peripheral refractive errors.

PURPOSE: To design and manufacture lenses to correct peripheral refraction along the horizontal meridian and to determine whether these resulted in noticeable improvements in visual performance. METHODS: Subjective refraction of a low myope was determined on the basis of best peripheral detection acuity along the horizontal visual field out to ±30° for both horizontal and vertical gratings. Subjective refraction was compared to objective refractions using a COAS-HD aberrometer. Special lenses were made to correct peripheral refraction, based on designs optimized with and without smoothing across a 3-mm diameter square aperture. Grating detection was retested with these lenses. Contrast thresholds of 1.25-min arc spots were determined across the field for the conditions of best correction, on-axis correction, and the special lenses. RESULTS: The participant had high relative peripheral hyperopia, particularly in the temporal visual field (maximum, 2.9 D). There were differences >0.5 D between subjective and objective refractions at a few field angles. On-axis correction reduced peripheral detection acuity and increased peripheral contrast threshold in the peripheral visual field, relative to the best correction, by up to 0.4 and 0.5 log units, respectively. The special lenses restored most of the peripheral vision, although not all at angles to ±10°, and with the lens optimized with aperture smoothing possibly giving better vision than the lens optimized without aperture smoothing at some angles. CONCLUSIONS: It is possible to design and manufacture lenses to give near-optimum peripheral visual performance to at least ±30° along one visual field meridian. The benefit of such lenses is likely to be manifest only if a subject has a considerable relative peripheral refraction, for example, of the order of 2 D.

Pupil shape as viewed along the horizontal visual field.

Changes in pupil size and shape are relevant for peripheral imagery by affecting aberrations and how much light enters and/or exits the eye. The purpose of this study is to model the pattern of pupil shape across the complete horizontal visual field and to show how the pattern is influenced by refractive error. Right eyes of 30 participants were dilated with 1% cyclopentolate, and images were captured using a modified COAS-HD aberrometer alignment camera along the horizontal visual field to ±90°. A two-lens relay system enabled fixation at targets mounted on the wall 3 m from the eye. Participants placed their heads on a rotatable chin rest, and eye rotations were kept to less than 30°. Best-fit elliptical dimensions of pupils were determined. Ratios of minimum to maximum axis diameters were plotted against visual field angle. Participants' data were well fitted by cosine functions with maxima at (-)1° to (-)9° in the temporal visual field and widths 9% to 15% greater than predicted by the cosine of the field angle . Mean functions were 0.99 cos([ + 5.3]/1.121), R(2) 0.99 for the whole group and 0.99 cos([ + 6.2]/1.126), R(2) 0.99 for the 13 emmetropes. The function peak became less temporal and the width became smaller with increase in myopia. Off-axis pupil shape changes are well described by a cosine function that is both decentered by a few degrees and flatter by about 12% than the cosine of the viewing angle, with minor influences of refraction.

Vision in water.

The purpose of this study is to determine visual performance in water, including the influence of pupil size. The water environment was simulated by placing goggles filled with saline in front of the eyes with apertures placed at the front of the goggles. Correction factors were determined for the different magnification under this condition in order to estimate vision in water. Experiments were conducted on letter visual acuity (seven participants), grating resolution (eight participants), and grating contrast sensitivity (one participant). For letter acuity, mean loss of vision in water, compared to corrected vision in air, varied between 1.1 log min of arc resolution (logMAR) for a 1 mm aperture to 2.2 logMAR for a 7 mm aperture. The vision in min of arc was described well by a linear relationship with pupil size. For grating acuity, mean loss varied between 1.1 logMAR for a 2 mm aperture to 1.2 logMAR for a 6 mm aperture. Contrast sensitivity for a 2 mm aperture deteriorated as spatial frequency increased with a 2 log unit loss by 3 c/°. Superimposed on this deterioration were depressions (notches) in sensitivity with the first three notches occurring at 0.45, 0.8, and 1.3 c/° with estimates for water of 0.39, 0.70, and 1.13 c/°. In conclusion, vision in water is poor. It becomes worse as pupil size increases, but the effects are much more marked for letter targets than for grating targets.

Experience from an immunohematology reference testing center.

Blood Centres in India lack infrastructure to investigate immunohematology problems. Reference Testing Center (RTC) was established in 2014 to investigate Immunohematological problem as it is not possible for small blood centers to go for complete immunohematology work up due to lack of financial and technical resources in remote and rural areas. Objective of this study is to share our experience as RTC of past 6 years so that more RTC are established across Indian subcontinent. 1456 Discrepant samples received from various hospitals of South India for Immunohematology problems were analysed in 6 years. Maximum requisitions obtained in 2014 were more than 40 years of age and then 21-40 years of age group in 2015 and same was observed till 2020.75% of total samples received were for antibody identification followed by blood group discrepancy resolution, investigation of positive DAT, red cell phenotype and pre-natal evaluation & antibody titration. Single allo-antibodies were identified in 773 cases whereas multiple allo-antibodies were found in 118 cases. Most common single and multiple antibody found was anti D and Anti-D+C. Weak D subgroup was the most common blood group discrepancy.22 cases & 4 cases of Bombay and para-bombay were also investigated.

Effect of age on components of peripheral ocular aberrations.

PURPOSE: To investigate the effect of age on the contributions of the anterior cornea and internal components to ocular aberrations in the peripheral visual field. METHODS: Ocular aberrations were measured in 10 young emmetropes and 7 older emmetropes using a modified commercial Hartmann-Shack aberrometer across 42° × 32° of central visual field. Anterior corneal aberrations were estimated from anterior corneal topography using theoretical ray-tracing. Internal aberrations were calculated by subtracting anterior corneal aberrations from ocular aberrations. RESULTS: Anterior corneal aberrations of young subjects were reasonably compensated by the internal aberrations, except for astigmatism for which the internal contribution was small out to the 21° field limit. The internal coma and spherical aberration of the older subjects were considerably smaller in magnitude than those of the young subjects such that the compensation for anterior corneal aberrations was poorer. This can be explained by age-related changes in the lens shape and refractive index distribution. CONCLUSIONS: Loss of balance between anterior cornea and internal components of higher order aberrations with increasing age, found previously for on-axis vision, applies also to the peripheral visual field.

Eye shape and retinal shape, and their relation to peripheral refraction.

PURPOSE: We provide an account of the relationships between eye shape, retinal shape and peripheral refraction. RECENT FINDINGS: We discuss how eye and retinal shapes may be described as conicoids, and we describe an axis and section reference system for determining shapes. Explanations are given of how patterns of retinal expansion during the development of myopia may contribute to changing patterns of peripheral refraction, and how pre-existing retinal shape might contribute to the development of myopia. Direct and indirect techniques for determining eye and retinal shape are described, and results are discussed. There is reasonable consistency in the literature of eye length increasing at a greater rate than height and width as the degree of myopia increases, so that eyes may be described as changing from oblate/spherical shapes to prolate shapes. However, one study indicates that the retina itself, while showing the same trend, remains oblate in shape for most eyes (discounting high myopia). Eye shape and retinal shape are not the same and merely describing an eye shape as being prolate or oblate is insufficient without some understanding of the parameters contributing to this; in myopia a prolate eye shape is likely to involve both a steepening retina near the posterior pole combined with a flattening (or a reduction in steepening compared with an emmetrope) away from the pole. SUMMARY: In the recent literature, eye and/or retinal shape have often been inferred from peripheral refraction, and, to a lesser extent, vice versa. Because both the eye's optics and the retinal shape contribute to the peripheral refraction, and there is large variation in the latter, this inference should be made cautiously. Recently retinal shape has been measured independent of optical methods using magnetic resonance imaging. For further work on retinal shape, determining the validity of cheaper alternatives to magnetic resonance techniques is required.

Post-prandial paradoxical filling of gall bladder in patients with acute hepatitis: Myth or reality?

BACKGROUND: A minority of patients of acute hepatitis may exhibit edematous GB walls with no visible lumen despite fasting and may also exhibit paradoxical GB response in the post-prandial state. METHODS: Patients of acute hepatitis underwent routine upper abdominal sonography after overnight fasting. Patients who demonstrated contracted GB with edematous and coapted walls without any visible lumen despite overnight fasting were studied in the post-prandial phase after having breakfast. Serial ultrasonography was carried out at 10-15 min interval for an hour and changes in GB morphology was noted at each stage. RESULTS: A total of 77 patients of acute hepatitis underwent USG of hepatobiliary system between Sept 2008 and Aug 2009. Contracted gall bladder with edematous and coapted walls without any visible lumen despite overnight fasting was noted in 11 patients and were studied in the post-prandial phase. Post-prandial paradoxical filling of GB was observed in all such cases. Serial post-prandial ultrasonography demonstrated onset of filling of GB as early as 10-15 min post-prandial. Maximal GB distension was observed between 30 and 60 min. USG at 60 min post-prandial showed slight reduction in GB volume. As the GB distended in the post-prandial state, the lumen became increasingly visible with marginal reduction in wall thickening. CONCLUSION: We have observed transient paradoxical filling of GB on serial USG in early post-prandial state, in a subset of patients of acute viral hepatitis who had contracted GB with coapted walls in the initial USG after overnight fasting.