Modification of the hand-held Vscan ultrasound and verification of its performance for transvaginal applications.

PURPOSE: The purpose of this work was to validate a new clinical obstetrics and gynecology (OB-GYN) application for a hand-held ultrasound (US) device. We modified the smallest hand-held device on the market and tested the system for transvaginal (TV) use. This device was originally conceived for abdominal scanning only. METHODS: The validation involved 80 successive patients examined by the same operator: 25 obstetric and 55 gynecologic cases. US examination was performed transvaginally with two US systems: the hand-held Vscan (General Electrics; GE Vingmed Ultrasound; Norway) for which an intravaginal gadget TTGP-2010® (Troyano transvaginal gadget probe) was designed, and the Voluson 730 Expert (multifrequency transvaginal ultrasound of 3-9MHz; GE Healthcare, Milwaukee, WI, USA). We performed the same measurements with both US systems in order to confirm whether or not their diagnostic capability was similar. Quantitative difference in measurements between the systems was assessed, as well as the overall diagnostic detection rate and suitability for telemedicine. RESULTS: Regarding lesion visibility with Vscan, optimal distance was 8-16cm depending on the examination type, and the total detection rate was 98.7%. The exception was an ovarian endometrioma, diagnosed as a follicular cyst using the hand-held device. Assessment of reproducibility in 180 measurements showed that the measurements obtained with Vscan were 0.3-0.4cm lower than those obtained with the high resolution US device (Voluson 730 Expert). Nevertheless, Pearson's correlation coefficient was high for biparietal diameter (0.72) and gynecological (GYN) (0.99) measurements, and for overall correlation (0.997). Image transport on USB and SD-flash cards proved convenient for telemedicine. CONCLUSIONS: A novel TV application of a hand-held US device is demonstrated for OB-GYN. Heart, abdominal and obstetrics presets of the Vscan together with color-Doppler enable a detection capability comparable to that of a high-definition US device. The lower values of the measurements obtained by the hand-held device (by 0.3-0.4cm) must be taken into account, although they have no effect on its diagnostic capability.

Diagnóstico prenatal y caracterización por SKY (cariotipo espectral multicolor) de cromosomas extra estructuralmente anormales (ESAC) / Prenatal diagnosis and multicolor spectral kariotyping characterization of the extra structurally abnormal chromosomes

Los cromosomas extra estructuralmente anormales (ESAC) son pequeños cromosomas supernumerarios asociados con cierta frecuencia con el desarrollo de anormalidades. Hemos revisado 9.987 estudios citogenéticos prenatales de células de líquido amniótico, encontrando tres casos con presencia de ESAC. Cada uno de estos cromosomas fueron analizados con varias técnicas con el fin de determinar su estructura, y con las técnicas citogenéticas moleculares como el FISH (hibridización in situ por fluorescencia) y SKY (cariotipo espectral multicolor). En dos casos pudimos determinar la presencia de ESAC en otros miembros normales de la familia. Un tercer caso de ESAC de novo fue detectado, y el origen cromosómico pudo ser determinado por SKY: 47,xx,+der(22) (q12-qter). La introducción de las técnicas de citogenética molecular como el SKY tiene un importante impacto en el correcto diagnóstico y en el consejo genético de acuerdo con la necesidad del paciente

Extra structurally abnormal chromosomes (ESACs) are small supernumerary chromosomes often associated with developmental abnormalities. We have revised 9,987 prenatal cytogenetic studies of amniotic fluid cells finding 3 cases with the presence of ESACs. Each of these chromosomes was analyzed with various staining techniques in orden to determine its structure, and with molecular cytogenetics techniques such FISH (fluorescence in situ hibridization) and SKY (multicolor spectral kariotyping). In two cases we could determine the presence of ESACs in other normal members of the families. In the third case a de novo ESAC was detected, and the chromosomal origin could be identified by SKY: 47,XX,+der(22)(q12-qter). The introduction of molecular cytogenetics techniques such SKY has a great impact on the correct diagnosis and we offered the genetic counseling according with the need of the patients

Malformaciones del corazón izquierdo (Hipoplasia del ventrículo izquierdo. HVI) / Left heart hypoplasia (Left heart malformations)

La Hipoplasia del ventrículo izquierdo representa una de las cardiopatías con mayor índice de mortalidad neonatal. El diagnóstico prenatal debe incluir no sólo la valoración del volumen ventricular izquierdo, sino la detección de otras anomalías asociadas que generalmente afectan a todo el tracto de hemicardio izquierdo. El diagnóstico precoz a pesar de la dificultad que entraña, es un factor determinante de la conducta obstétrica, ya que en algunas circunstancias la asociación con otras alteraciones estructurales pueden mejorar el infausto pronóstico de estos fetos. El estudio morfológico, los signos funcionales indirectos y el Doppler Color se erigen como elementos preceptivos para la valoración prenatal del síndrome de la hipoplasia de cavidades izquierdas (AU)

Virtual sonography through the Internet: volume compression issues.

BACKGROUND: Three-dimensional ultrasound images allow virtual sonography even at a distance. However, the size of final 3-D files limits their transmission through slow networks such as the Internet. OBJECTIVE: To analyze compression techniques that transform ultrasound images into small 3-D volumes that can be transmitted through the Internet without loss of relevant medical information. METHODS: Samples were selected from ultrasound examinations performed during, 1999-2000, in the Obstetrics and Gynecology Department at the University Hospital in La Laguna, Canary Islands, Spain. The conventional ultrasound video output was recorded at 25 fps (frames per second) on a PC, producing 100- to 120-MB files (for from 500 to 550 frames). Processing to obtain 3-D images progressively reduced file size. RESULTS: The original frames passed through different compression stages: selecting the region of interest, rendering techniques, and compression for storage. Final 3-D volumes reached 1:25 compression rates (1.5- to 2-MB files). Those volumes need 7 to 8 minutes to be transmitted through the Internet at a mean data throughput of 6.6 Kbytes per second. At the receiving site, virtual sonography is possible using orthogonal projections or oblique cuts. CONCLUSIONS: Modern volume-rendering techniques allowed distant virtual sonography through the Internet. This is the result of their efficient data compression that maintains its attractiveness as a main criterion for distant diagnosis.

Small marker chromosomes in a series of 1,000 prenatal diagnoses by amniocentesis.

We diagnosed two small marker chromosomes in a series of 1,000 prenatal cytogenetic studies of amniotic fluid cells. Each of these chromosomes was analyzed with various staining techniques in order to determine its structure and the possible mechanism of its formation. On the basis of the results thus obtained and the familial nature of these abnormalities, we predicted phenotypically normal fetuses in both cases. Postnatal follow-up confirmed this. Notwithstanding the correct diagnoses made in these two cases, we feel that a more substantial body of literature on this type of anomaly must become available before it will be possible to give firm genetic counselling in such cases.

A rare case of de novo structural rearrangement of X chromosome diagnosed by amniocentesis.

A dicentric X chromosome was found in a female fetus during cytogenetic studies performed on amniotic cells. Blood samples from the parents showed normal karyotypes and the pregnancy was terminated. The mechanism for the formation of this 'de novo' rearrangement is discussed.