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Biomedical subjects

R S Lachman

Publications and source records attributed to R S Lachman.

At least 91 records · Page 5Linked to original sources

Perinatal lethal hypophosphatasia; clinical, radiologic and morphologic findings.

Clinical, radiographic and morphologic analysis of nineteen cases of perinatal (lethal) hypophosphatasia was performed. Three families each had two affected offspring. All of the patients had lethal short limb dwarfism with very soft calvaria. Other clinical findings included polyhydramnios, blue sclerae and spurs in the mid-portion of the forearms and lower legs. Considerable variability was found in the skeletal radiographs. In addition to the well known radiographic features such as generalized decrease in the size of ossified bones with some bones not ossified at all, other changes observed included: 1) marked variability in the amount of bone ossification; 2) variability between patients as to which bones were most severely affected; 3) unusually dense, round, flattened, butterfly shaped; and sagittally clefted vertebral bodies; 4) variability in femoral shape including "chromosome" like, "campomelic" like, and shortening with or without metaphyseal cupping or irregularities; 5) osteochondral projections (Bowdler spurs) of the midshaft of the fibula and ulna. Recognition of the marked clinical and radiographic variability in this autosomal recessive lethal skeletal dysplasia is important for accurate genetic counseling and prenatal diagnosis.

Bone and Bones↗

Atelosteogenesis type III: a distinct skeletal dysplasia with features overlapping atelosteogenesis and oto-palato-digital syndrome type II.

We present 5 cases of a short-limb dwarfism syndrome whose manifestations overlap those of atelosteogenesis and oto-palato-digital syndrome Type II. Clinical, radiographic, genetic, and histologic data are presented which demonstrate differences between our patients and previously reported cases of these other conditions. We conclude that the disorder seen in these children represents a distinct chondrodysplasia for which we propose the name atelosteogenesis Type III.

Bone and Bones↗

Possible heterogeneity in spondyloenchondrodysplasia: quadriparesis, basal ganglia calcifications, and chondrocyte inclusions.

We report on 6 patients with short stature and progressive enchondromatous-like changes of the vertebral bodies and the metaphyses of the long bones. Parental consanguinity was observed in 5 of 6 cases, supporting autosomal recessive inheritance. In spite of the similarity in radiographic changes and body proportions, genetic heterogeneity is suggested by the presence of CNS calcifications in 3 patients. Two of the latter had progressive quadriparesis. We tentatively classified these patients into 2 provisional types. An iliac crest biopsy in one of the patients with "type I" disease did not demonstrate enchondromatosis. Light and transmission electron microscopic studies demonstrated large cisterns and small inclusion bodies containing a flocculent material within the rough endoplasmic reticulum of the chondrocytes. Based on the histological and radiographic findings, we propose to classify these conditions among the spondylometaphyseal skeletal dysplasias.

Adolescent↗

Quantitative histology of cartilage vascular canals in the human rib. Findings in normal neonates and children and in achondrogenesis II-hypochondrogenesis.

Knowledge of the structure of cartilage vascular canals is important for a more thorough understanding of the development of cartilage and the growth plate in the human neonate and growing child. We have studied the costochondral junction of 6 normal neonates and 12 normal children (age 4 months-16 years) and utilised quantitative histomorphometry to define the percentage tissue area occupied by canals and the number of canals/mm2. Both percentage canal area and the number of canals/mm2 were significantly greater in newborn vs. older children (percentage area: 0.42 +/- 0.15 (mean +/- S.E.M.) vs. 0.08 +/- 0.04, P = 0.003; number/mm2: 0.2 +/- 0.09 vs. 0.04 +/- 0.02, P = 0.02). Eight newborn patients with achondrogenesis II-hypochondrogenesis were also studied. Both percentage canal area and number were significantly elevated above normal (percentage area: 5.22 +/- 1.01, P less than 0.001; number/mm2: 1.45 +/- 0.26, P less than 0.001). Results presented here demonstrate that: (i) quantitative differences in vascular canal area and numbers occur during development; (ii) 10-fold increases in vascular canal area and number are present in achondrogenesis II-hypochondrogenesis. Data from normal subjects will provide normative values against which vascular abnormalities in other skeletal dysplasias can be compared.

Aging↗

Calcospherite (calcification nodule) size in the short rib polydactyly syndromes.

The short rib polydactyly syndromes (SRP) are lethal neonatal skeletal dysplasias with a narrow chest, short limbs, and other abnormalities. Type II (Majewski) short rib polydactyly can be distinguished from the Type I/III (Saldino-Noonan) type on the basis of radiographic and histologic changes. Our previous transmission electron microscopic studies suggested unusual patterns of cartilage calcification in these syndromes. We evaluate calcification in the present study using scanning electron microscopy and quantitative morphometry of calcification regions digested to expose calcospherite nodules (calcification nodules), distinctive morphologic structures which form during cartilage calcification. Mean calcospherite area of the Majewski Type II SRP (3.5 +/- 0.24 x 10(-6) mm2 (3) (mean +/- sem (n) did not differ from normal control means (3.1 +/- 0.5 x 10(-6) mm2, (3)). The mean area for Type I/III, however, was significantly larger than both the control and Type II means (8.9 +/- 1.16 x 10(-6) mm2 (7), p = .001). This difference in calcospherite size adds a further differentiating feature between these two dysplasias.

Calcinosis↗

Fetal imaging in the skeletal dysplasias.

Second-trimester diagnosis of fetal skeletal dysplasia is becoming increasingly common. By careful examination of the fetus for skeletal mineralization, shape and size of long bones and cranium, and abnormalities of other organ systems, a definitive diagnosis can often be achieved by ultrasound. Fetal radiography is very helpful in giving more information about bone shape and mineralization as well as in confirming the diagnosis. Subsequent obstetric management should be dictated by the natural history of the disease, the parents' wishes, and the gestational age at diagnosis. Because many of these disorders have a high recurrence risk, genetic counseling and follow-up are an important part of the management of these patients.

Bone Diseases, Developmental↗

Apparently previously undescribed X-linked dominant syndrome with facial and skeletal anomalies.

We report on a syndrome of widow's peak, ptosis, skeletal abnormalities and other minor anomalies in a large family. The condition appears to be inherited in an X-linked dominant fashion. No similar cases have been found in the literature, suggesting that this is a "new" syndrome. Study of 5 generations of the family documents information on the natural history of the condition.

Adolescent↗

Sponastrime dysplasia. A radiologic-pathologic correlation.

The 2nd family with Sponastrime Dysplasia is described. The clinical, radiologic and chondro-osseous morphology of boy and girl siblings are presented. The facial appearance is an "oriental look" with midface hypoplasia and a saddle nose. The radiological findings include the spinal changes of lordosis, osteoporosis and pear-shaped vertebrae, as well as striated metaphyses (osteopathia striata). The morphological findings suggest a disturbance in the formation of cartilage, with a defect in collagen and proteoglycans synthesis in this rare autosomal recessive skeletal dysplasia.

Bone Diseases, Developmental↗

A new autosomal recessive lethal chondrodystrophy with congenital hydrops.

Two sibs, the offspring of consanguineous parents, presented with severe short-limb dwarfism and distinct chondro-osseous, radiologic, and histologic appearance. The first sib presented at 30 wk with severe hydrops following fetal death; the second was detected by ultrasonography at 20 wk. Radiologic abnormalities included an unusual "moth-eaten" appearance of the markedly short long bones, bizzare ectopic ossification centers, and marked platyspondyly with unusual ossification centers. Marked extramedullary erythropoiesis was present in both fetuses, and chondro-osseous histology was characterized by marked disorganization of tissue with interspersed masses of cartilage, bone, and mesenchymal tissue. These sibs appear to have a distinct previously unreported autosomal recessive skeletal dysplasia, which can present as hydrops fetalis.

Adult↗

Metaphyseal chondrodysplasia, Schmid type. Clinical and radiographic delineation with a review of the literature.

Analysis of 20 cases of metaphyseal chondrodysplasia, Schmid type as well as a review of the world literature reveals a specific autosomal dominant disorder that was often over-diagnosed in the past, sometimes resulting in incorrect genetic counselling. Significant radiologic features include an enlarged capital femoral epiphysis in early childhood, coxa vara, greater involvement of the distal femoral metaphysis than the proximal, anterior rib changes and a normal spine. Chondroosseous morphology is not specific. Presentation in nonfamilial cases is no earlier than the second year of life.

Child↗

Prenatal diagnosis of osteogenesis imperfecta type III.

Ultrasonographic and radiographic evaluation of a fetus at risk for osteogenesis imperfecta (O.I) type III was performed. Real-time ultrasound measurements at 15 weeks gestation were interpreted as normal, but at 20 and 22 weeks of gestation revealed marked shortening of the long bones and deformity of the femurs. The findings were confirmed by fetal radiography at 22 weeks gestation. Radiographic and histologic changes characteristic of O.I. were observed in the aborted fetus. Thus the antenatal manifestations of O.I. type III maybe severe enough to make prenatal diagnosis possible in the second trimester for families at risk for recurrence of this disorder.

Adult↗

Radiation exposure reduction by use of Kevlar cassettes in the neonatal nursery.

A study was performed to determine whether the use of Kevlar cassettes in the neonatal intensive care nursery would reduce radiation exposure to patients. The radiation dose to the neonates was measured by using thermoluminescent dosimeters. In addition, the attenuation of the Kevlar cassettes and the sensitivity of the film-screen combination were compared with the previously used system. The greatest radiation reduction using a mobile X-ray unit was 27%; based on sensitivity measurements, the theoretical reduction averaged 38%. The reduction in radiation exposure resulted from reduced attenuation by the Kevlar cassette.

Body Weight↗

Bridging bronchus and posterior left pulmonary artery: a unique association.

A 6-month-old female with a lifelong history of respiratory distress became increasingly difficult to manage and required right upper and middle pulmonary lobectomies for worsening emphysema and mediastinal shift. The postoperative course was stormy and confusing and the patient died despite emergency tracheostomy. The autopsy disclosed an anomalous bronchus to the right lower lobe, originating from the left mainstem bronchus. In addition, the left main pulmonary artery was positioned posterior to the left mainstem bronchus. Two other cases of bridging bronchus have been reported, but the association with posterior left pulmonary artery has not been described.

Adult↗

Pseudodiastrophic dysplasia: a distinct newborn skeletal dysplasia.

Pseudodiastrophic dysplasia is a distinct disorder that differs from diastrophic dysplasia on the basis of clinical, radiographic, and chondro-osseous histopathologic findings. In addition to the rhizomelic shortening of the limbs and severe clubfoot deformity, which suggest the diagnosis of diastrophic dysplasia, distinguishing features are elbow and proximal interphalangeal joint dislocations, platyspondyly, and scoliosis, which are observed in infancy. This disorder has been reported previously in three infants, all of whom died in the first year of life. Two of these were sisters, suggesting autosomal recessive inheritance. We report four new patients with this distinct skeletal dysplasia, including two children now older than 4 years of age. In both of these patients neonatal contractures have improved with physical therapy and scoliosis has progressed significantly.

Bone Diseases, Developmental↗

A new skeletal dysplasia: clinical, radiologic, and pathologic findings.

Two siblings, one male and one female, were noted to have a distinct skeletal dysplasia. The clinical and radiographic features resemble those observed in Kniest dysplasia and Rolland-Desbuquois syndrome, but important differences were noted. Specifically, these two patients have microstomia, "pursed" lips, and ectopia lentis, and their radiographs reveal no coronal clefts. Chondro-osseous features also differ from those observed in either of the other disorders. Scattered dense patches consisting of collagen fibers 10 to 30 times broader than normal are seen scattered throughout the cartilage matrix; the "Swiss cheese" appearance characteristic of Kniest dysplasia is not observed. These patients appear to have a new skeletal dysplasia, most likely inherited in an autosomal recessive fashion.

Bone Diseases, Developmental↗