Hypoglossal nerve trunk stimulation: electromyography findings during drug-induced sleep endoscopy: a case report.

BACKGROUND: Literature has demonstrated hypoglossal nerve stimulation to be a safe and effective treatment for patients with obstructive sleep apnea nonadherent to positive airway pressure therapy. However, the recommended criteria for patient selection are still unable to identify all the unresponsive patients, highlighting the need for improved understanding about hypoglossal nerve stimulation for obstructive sleep apnea. CASE PRESENTATION: A 48-year-old Caucasian male patient with obstructive sleep apnea had been successfully treated with electrical stimulation of the hypoglossal nerve trunk, documented by level 1 polysomnography data. However, due to snoring complaints, he underwent postoperation drug-induced sleep endoscopy for evaluation of electrode activation during upper airway collapse, aiming to improve electrostimulation parameters. Concurrent surface electromyography of the suprahyoid muscles and masseter was obtained. Activation of electrodes 2, 3, and 6 promoted upper airway opening most strongly at the velopharynx and tongue base during drug-induced sleep endoscopy. The same channels also significantly increased the electrical activity on suprahyoid muscles bilaterally, but predominantly on the stimulated side (right). The masseters also presented a considerable asymmetry in electrical potential on the right side (> 55%). CONCLUSION: Beyond the genioglossus muscle, our findings demonstrate recruitment of other muscles during hypoglossal nerve stimulation, which may be attributed to the electrical stimulation of the nerve trunk. This data provides new insights on how stimulation of the hypoglossal nerve trunk may contribute to obstructive sleep apnea treatment.

Effects of carotid pressure waveforms on the results of wave separation, wave intensity and reservoir pressure analysis.

OBJECTIVE: Recently great attention has been paid to innovative cardiovascular biomarkers obtained from wave separation (WS), wave intensity (WI) and reservoir-wave (RW) theories. All these approaches share a requirement for pressure information. The aim of this study was to evaluate differences in WS-, WI- and RW-derived parameters obtained achieving pressure waveforms in different ways. APPROACH: Twenty-two individuals (49 ± 17 years, 59% males) were examined. Common carotid blood flow waveforms were obtained from pulsed-wave Doppler images. Carotid pressure waveforms were achieved in four different ways: (1) with applanation tonometry, used as a reference method; (2) linear scaling from an ultrasound (US)-derived diameter curve; (3) exponential scaling from a US-derived diameter curve; and (4) linear scaling from an accelerometric-derived diameter signal. For each case, the reflection magnitude (RM) and index (RI) were obtained from the WS. The amplitude of the first positive peak (W 1), of the second positive peak (W 2) and of the negative peak (W b) were calculated from the WI, while the maximum of the reservoir (maxPr) and the excess (maxPex) pressure were achieved from the RW. MAIN RESULTS: According to the intra-class coefficient values, the agreement between the standard method and all the others was excellent for the RM (linear: 0.82; exponential: 0.83; accelerometric: 0.86), RI (linear: 0.84; exponential: 0.85; accelerometric: 0.87), maxPr (linear: 0.97; exponential: 0.96; accelerometric: 0.97) and maxPex (linear: 0.85; exponential: 0.87; accelerometric: 0.89), while only a fair/good level was reached for W 1 (linear: 0.67; exponential: 0.77; accelerometric: 0.52), W 2 (linear: 0.52; exponential: 0.69; accelerometric: 0.83) and W b (linear: 0.60; exponential: 0.44; accelerometric: 0.50). SIGNIFICANCE: Measuring carotid pressure waveforms with different approaches does not influence the cardiovascular parameters obtained by WS and RW; those derived by WI are affected by the carotid pressure curve employed.

Associative bacteria influence maize (Zea mays L.) growth, physiology and root anatomy under different nitrogen levels.

Despite the great diversity of plant growth-promoting bacteria (PGPB) with potential to partially replace the use of N fertilisers in agriculture, few PGPB have been explored for the production of commercial inoculants, reinforcing the importance of identifying positive plant-bacteria interactions. Aiming to better understand the influence of PGPB inoculation in plant development, two PGPB species with distant phylogenetic relationship were inoculated in maize. Maize seeds were inoculated with Bacillus sp. or Azospirillum brasilense. After germination, the plants were subjected to two N treatments: full (N+) and limiting (N-) N supply. Then, anatomical, biometric and physiological analyses were performed. Both PGPB species modified the anatomical pattern of roots, as verified by the higher metaxylem vessel element (MVE) number. Bacillus sp. also increased the MVE area in maize roots. Under N+ conditions, both PGPB decreased leaf protein content and led to development of shorter roots; however, Bacillus sp. increased root and shoot dry weight, whereas A. brasilense increased photosynthesis rate and leaf nitrate content. In plants subjected to N limitation (N-), photosynthesis rate and photosystem II efficiency increased in maize inoculated with Bacillus sp., whilst A. brasilense contained higher ammonium, amino acids and total soluble sugars in leaves, compared to the control. Plant developmental and metabolical patterns were switched by the inoculation, regardless of the inoculant bacterium used, producing similar as well as distinct modifications to the parameters studied. These results indicate that even non-diazotrophic inoculant strains can improve the plant N status as result of the morpho-anatomical and physiological modifications produced by the PGPB.

Acclimation responses to high light by Guazuma ulmifolia Lam. (Malvaceae) leaves at different stages of development.

The re-composition of deforested environments requires the prior acclimation of seedlings to full sun in nurseries. Seedlings can overcome excess light either through the acclimation of pre-existing fully expanded leaves or through the development of new leaves that are acclimated to the new light environment. Here, we compared the acclimation capacity of mature (MatL, fully expanded at the time of transfer) and newly expanded (NewL, expanded after the light shift) leaves of Guazuma ulmifolia Lam. (Malvaceae) seedlings to high light. The seedlings were initially grown under shade and then transferred to full sunlight. MatL and NewL were used for chlorophyll fluorescence and gas exchange analyses, pigment extraction and morpho-anatomical measurements. After the transfer of seedlings to full sun, the MatL persisted and acclimated to some extent to the new light condition, since they underwent alterations in some morpho-physiological traits and maintained a functional electron transport chain and positive net photosynthesis rate. However, long-term exposure to high light led to chronic photoinhibition in MatL, which could be related to the limited plasticity of leaf morpho-anatomical attributes. However, the NewL showed a high capacity to use the absorbed energy in photochemistry and dissipate excess energy harmlessly, attributes that were favoured by the high structural plasticity exhibited by these leaves. Both the maintenance of mature, photosynthetically active leaves and the production of new leaves with a high capacity to cope with excess energy were important for acclimation of G. ulmifolia seedlings.

Ageing and inflammation in patients with HIV infection.

Nowadays, HIV+ patients have an expected lifespan that is only slightly shorter than healthy individuals. For this reason, along with the fact that infection can be acquired at a relatively advanced age, the effects of ageing on HIV+ people have begun to be evident. Successful anti-viral treatment is, on one hand, responsible for the development of side effects related to drug toxicity; on the other hand, it is not able to inhibit the onset of several complications caused by persistent immune activation and chronic inflammation. Therefore, patients with a relatively advanced age, i.e. aged more than 50 years, can experience pathologies that affect much older citizens. HIV+ individuals with non-AIDS-related complications can thus come to the attention of clinicians because of the presence of neurocognitive disorders, cardiovascular diseases, metabolic syndrome, bone abnormalities and non-HIV-associated cancers. Chronic inflammation and immune activation, observed typically in elderly people and defined as 'inflammaging', can be present in HIV+ patients who experience a type of premature ageing, which affects the quality of life significantly. This relatively new condition is extremely complex, and important factors have been identified as well as the traditional behavioural risk factors, e.g. the toxicity of anti-retroviral treatments and the above-mentioned chronic inflammation leading to a functional decline and a vulnerability to injury or pathologies. Here, we discuss the role of inflammation and immune activation on the most important non-AIDS-related complications of chronic HIV infection, and the contribution of aging per se to this scenario.

Phenology of two Ficus species in seasonal semi-deciduous forest in Southern Brazil.

We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23° 27'S and 51° 15'W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

Phenology of two Ficus species in seasonal semi-deciduous forest in Southern Brazil / Fenologia de duas espécies de Ficus em floresta estacional semidecidual no sul do Brasil

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27’S and 51°15’W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27’S e 51°15’W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.

Phenology of two Ficus species in seasonal semi-deciduous forest in Southern Brazil

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27S and 51°15W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27S e 51°15W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.

Laparoscopic resection of a jejunal mesenteric pseudocyst: case report.

Mesenteric cysts are rare and can occur at any age. They can manifest with abdominal pain or compressive mass effect. The exact etiology is unknown. Ultrasonography, computed tomography and laparoscopy are used in diagnosing mesenteric cysts. Laparoscopic excision of a mesenteric cyst is possible and should be considered as the treatment of choice. We present a case of mesenteric pseudocyst of small bowel treated by laparoscopic excision.

A chemically-modified inactive antithrombin as a potent antagonist of fondaparinux and heparin anticoagulant activity.

BACKGROUND: Heparin and its analogs, mediating their anticoagulant activity through antithrombin (AT) activation, remain largely used for the preventive and curative treatment of thrombosis. The major adverse reaction of these drugs is the bleeding risk associated with overdose. Unfractionnated heparin (UFH) can be efficiently and rapidly neutralized by protamine sulfate, but this reversal partially neutralizes low-molecular-weight heparin (LMWH) and is inefficient in reversing fondaparinux. To secure administration of AT-mediated anticoagulants and counteract bleeding disorders, we previously designed a recombinant inactive AT as an antidote to heparin derivatives. OBJECTIVES: To get around the limited production level of recombinant AT, we propose in this study an alternative strategy to produce a chemically modified inactive AT, exhibiting increased heparin affinity, as an antagonist of heparin analogs. METHODS: Plasma-derived AT was chemically modified with 2,3 butanedione, a diketone known to specifically react with the arginine side chain. The chemical reaction was conducted in the presence of heparin to preserve basic residues within the heparin binding site from modifications. RESULTS: AT treated by butanedione and selected for its high heparin affinity (AT-BD) was indeed modified on reactive Arg393 and thus exhibited decreased anticoagulant activity and increased heparin affinity. AT-BD was able to neutralize anticoagulant activity of heparin derivatives in vitro and in vivo and was devoid of intrinsic anticoagulant activity, as assessed by activated partial thromboplastin time assay. CONCLUSIONS: AT-BD appears to be as efficient as protamine to neutralize UFH in vivo but could be more largely used because it also reverses fondaparinux and LMWH.

Evaluation of the cardiovascular health study (CHS) instrument and the Vulnerable Elders Survey-13 (VES-13) in elderly cancer patients. Are we still missing the right screening tool?

BACKGROUND: A geriatric screening tool would be valuable to identify elderly cancer patients who might benefit from a comprehensive geriatric assessment (CGA). This study evaluated the accuracy of the cardiovascular health study (CHS) instrument in predicting abnormality in CGA. The vulnerable elders' survey-13 (VES-13) was also evaluated. PATIENTS AND METHODS: Patients aged ≥ 70 years with solid tumors underwent a CGA after being screened with the CHS and VES-13. Analyses were conducted for the overall population and according to the disease status (early or advanced) and type of early cancer (breast or gastrointestinal, GI). RESULTS: Of 259 patients, 75% were impaired according to the CHS and 47% according to the VES-13. CGA impairment was reported in 171 patients (66%). In the overall population, overall accuracy, sensitivity and specificity of CHS in identifying CGA impairments were 74%, 87% and 49%, respectively. The corresponding figures for the VES-13 were 68%, 62% and 81%. Sensitivity and specificity of CHS in predicting CGA impairments in subgroups were early 81% and 55%, advanced 98% and 29%; early breast 78% and 69%, early GI 87.5% and 19%. CONCLUSIONS: The CHS compared favourably with VES-13 for sensitivity. However, the great variability in specificity observed with the CHS within subgroups limits its applicability in the global population.

Herniated lumbar disc treated with Global Postural Reeducation. A middle-term evaluation.

BACKGROUND: Herniated lumbar intervertebral disc (HLID) is a pathological condition frequently seen in rehabilitation medicine that is characterized by the compression of one or more nerve roots. AIM: The aim of this study was to describe the effects of Global Postural Reeducation on function and pain in patients with herniated disc at levels L4-L5 and/or L5-S1. MATERIALS AND METHODS: Twenty-four consecutive subjects were treated with Global Postural Reeducation. Before treatment, patients reported median average pain duration of 180 days. At the beginning of treatment and on days 15, 45, 120, and 180, all completed the Quebec Back Pain Disability Scale and the Numeric Pain Rating Scale. RESULTS: The median value of the Quebec Back Pain Disability Scale score decreased from 49 points at baseline to 22 points at 45 days. Moreover, the median Numeric Pain Rating Scale score decreased from 6 points at baseline to 2 points at 45 days. CONCLUSIONS: The present study indicates that Global Postural Reeducation is suitable for the conservative management of HLID. Moreover, patients gained a therapeutic benefit from being active participants in their recovery.

Genetic differentiation in Aspidosperma polyneuron (Apocynaceae) over a short geographic distance as assessed by AFLP markers.

Studies on intraspecific variation can contribute to the development of conservation strategies by identifying units of conservation for threatened species. Aspidosperma polyneuron is a tropical tree of seasonal semideciduous forests that is currently endangered and protected because it has been heavily logged for lumber, although it was once common in Brazil and neighboring countries. We investigated genetic structure in two samples of A. polyneuron collected from steep hillsides and from flat areas of a natural forest fragment in northern Paraná State, Brazil. Seven AFLP primer combinations yielded 200 markers, with a polymorphic rate of 88.5% for samples from the flat area and 99% for samples from the high declivity area. Total genetic diversity (H(T)) was 0.387, while the genetic diversity within the populations (H(S)) was 0.307 and 0.372, for samples from the flat and the high declivity areas, respectively. Genetic differentiation between samples was high, with a mean F(ST) of 0.265 and a genetic distance of 0.148, indicative of a high degree of genetic structure over a short distance. Principal coordinate analysis separated the samples into three groups of individuals; the first group included individuals from the high declivity area, the second group consisted of individuals only from the flat area, and the third group had individuals from both areas. Bayesian analysis also showed K = 3 clusters. The unexpected high level of intraspecific variation of A. polyneuron in this small forest fragment should be taken into account when evaluating the genetic impact of forest degradation on this species in other semideciduous forest fragments.

Genetic diversity and flooding survival in Aegiphila sellowiana (Lamiaceae), a typical tree species from upland riparian forests.

Saplings of Aegiphila sellowiana were submitted to flooding and analysis of genetic diversity in order to investigate flooding tolerance as well as its genetic determination. This response is important because it means that some lines could be planted in degraded riparian areas. Leaves were sampled from each plant, and they were submitted to different flooding periods. Mortality of saplings was 40, 80, 50, 53.3, 33.3, and 33.3% in flooding for 15, 18, 25, 50, 80 days, and flooding for 50 days followed by re-aeration for 30 days, respectively. From the total number of flooded plants, 46.7% died in the first seven days of treatment, while 53.3% survived the flooding. The percentage of polymorphic loci (P(p)), Nei's genetic diversity (H) and the Shannon index (I) were slightly higher for the group that survived the stress of flooding (surviving: P(p) (%) = 67.48, H = 0.184, I = 0.287; not surviving: P(p) (%) = 66.67, H = 0.165, I = 0.261). Analysis of molecular variance showed that 5.88% of the genetic variability was due to the differences between groups of plants surviving and not surviving flooding, while 94.12% was due to genetic differences between individuals within these groups. Similar results were obtained by principal coordinate analysis. Based on these results, we can assume the existence of environment-specific genotypes and the genetic determination of flooding tolerance in A. sellowiana. Thus, some lines of A. sellowiana could be used in the reforestation of riparian habitats, especially in uplands along riverbanks.

Anatomy and genetic diversity of two populations of Schinus terebinthifolius (Anacardiaceae) from the Tibagi River basin in Paraná, Brazil.

Knowledge of the effects of flooding on plant survival is relevant for the efficiency of management and conservation programs. Schinus terebinthifolius is a tree of economic and ecological importance that is common in northeast Brazil. Flooding tolerance and genetic variation were investigated in two riparian populations of S. terebinthifolius distributed along two different ecological regions of the Tibagi River basin. Flooding tolerance was evaluated through the investigation of young plants, submitted to different flooding intensities to examine the morphological and anatomical responses to this stress. The growth rate of S. terebinthifolius was not affected by flooding, but total submersion proved to be lethal for 100% of the plants. Morphological alterations such as hypertrophied lenticels were observed in both populations and lenticel openings were significantly higher in plants from one population. Genetic analysis using DNA samples obtained from both populations showed a moderate degree of genetic variation between populations (13.7%); most of the variation was found within populations (86.3%). These results show that for conservation purposes and management of degraded areas, both populations should be preserved and could be used in programs that intend to recompose riparian forests.

Multiple spinal ganglioneuromas in a patient harboring a pathogenic NF1 mutation.

Ganglioneuroma is a rare benign tumor originating from autonomic ganglia and is considered the benign counterpart of neuroblastoma. Ganglioneuromas may be present as an isolated finding and, rarely, in association with neurofibromatosis type 1 (NF1). However, ganglioneuromas of the cervical spine with intradural extension and multiple locations are extremely rare. We describe a 32-year-old woman with multiple ganglioneuromas of the cervical, dorsal and lumbar spine associated with a few café-au-lait spots and subcutaneous nodules. The patient lacked other NF1 stigmata, such as freckling, Lisch nodules and cutaneous neurofibromas. Although our patient did not fulfill the NF1 diagnostic criteria, molecular diagnosis revealed a pathogenic mutation in the NF1 gene. Approximately 30 patients affected by NF1 and ganglioneuromas have been reported: in all these individuals, NF1 diagnosis was made according to the clinical diagnostic criteria and no patients have molecular diagnosis. Therefore, this is the first case with multiple spinal ganglioneuromas associated with a pathogenic NF1 mutation.

The term diplegia should be enhanced. Part III: inter-observer reliability of the new rehabilitation oriented classification.

AIM: The aim of this study was to validate a recent classification of gait in children with the spastic diplegic form of cerebral palsy (CP) by checking the reliability of different scorers in assigning subject walking performance to one of the four specific patterns described in the classification. METHODS: The gait patterns of 50 children and adolescents with CP (23 males, 27 females; age range 3-17 years) were selected among patients whose videos were stored in the archives of the Pisa and Reggio Emilia Hospitals. Only video recordings of gait with homogeneous features (duration of at least 90 s, simultaneous recordings on sagittal and frontal views, and other criteria) were taken for examination. The videos were blindly scored using an observational gait scale, at first by two of the authors of the classification system (defined as ''maximum experts''), then by ten expert observers, and finally by 206 professionals of rehabilitation after a one-day training on the classification. Cohen's kappa statistics (k) and intra class correlations (ICC) were calculated. RESULTS: Kappa and ICC indicate an almost perfect agreement both between the two maximum experts and among the ten expert observers. Good results were also obtained in the group of one-day trained scorers. Only a few cases were assigned to the ''unclassified'' category. The profession of the observer (doctor or therapist) and previous knowledge of the classification had no significant influence on reliability scores. CONCLUSION: The results suggest that the proposed classification can be reliably applied, even utilizing short video recordings, to arrange diplegic children into different patterns. Further studies are needed to validate the use of this classification system for clinical and research aims.

Brain magnetic resonance imaging in Wolf-Hirschhorn syndrome.

Wolf-Hirschhorn syndrome (WHS) is a rare genetic disorder, which is caused by partial deletion of the short arm of one chromosome 4. Brain magnetic resonance (MR) imaging findings are lacking. We report on brain findings in 10 children with WHS. We evaluated the MR imaging films of 10 subjects affected by WHS, which had been confirmed by genetic study. The age range at MR imaging was between 1 month and 9 years. In 9/10 cases enlargement of the third lateral ventricles was present. In 9/10 cases a global reduction of cerebral hemispheres white matter was present. In 10/10 cases diffuse thinning of the corpus callosum was visible; it was severe in 7/10 cases. In 5/10 cases small foci of T (2) hyper intense signal were visible within the subcortical white matter. In three of the six cases studied within the first year of life frontal periventricular cysts were present. In three of the four cases studied after the first year of life a squared shape of the frontal horns of the lateral ventricles was visible. The MR imaging findings reported in WHS cannot be considered pathognomonic of the syndrome, however, they may suggest WHS.

Hippocampal infolding angle changes during brain development assessed by prenatal MR imaging.

BACKGROUND AND PURPOSE: Epileptic syndromes or neurodevelopmental delay may be associated with congenital anomalies of the shape or the orientation of the hippocampus. Scarce data are available about quantitative hippocampal developmental changes during fetal life, in particular about the progressive rotational changes of the hippocampal infolding angle (HIA), which can be considered a hallmark of hippocampal development. We hypothesized that prenatal MR imaging could demonstrate the progressive rotation of the hippocampus, providing quantitative data by means of the HIA determination. METHODS: We retrospectively selected 62 fetal MR imaging cases with normal brain at prenatal and postnatal imaging. The gestational age ranged from 20 to 37 weeks. The coronal section encompassing the pons was used to perform the measurement of HIA. HIA was defined as the angle between the line connecting the lateral margin of the cornu ammonis with the medial superior margin of the subiculum and the line passing through the midline structures. RESULTS: A significant positive correlation was found between the HIA value and the gestational age. The HIA was generally below 70 degrees before the gestational week 25 and above 70 degrees after week 30. CONCLUSION: Prenatal MR imaging allowed the progressive rotation of hippocampus to be detected during fetal life, providing normative data about HIA changes. These data could support further investigations to assess how fetal HIA anomalies might affect postnatal neurologic outcome.