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P H Abrahams

Publications and source records attributed to P H Abrahams.

15 recordsLinked to original sources
PubMed2005

Anatomical considerations of the pediatric ilioinguinal/iliohypogastric nerve block.

BACKGROUND: The ilioinguinal/iliohypogastric nerve block is safe, effective and easy to perform in order to provide analgesia for a variety of inguinal surgical procedures in pediatric patients. A relatively high failure rate of 10-25% has been reported, even in experienced hands. The aim of this study was to determine the exact anatomical position of the ilioinguinal and iliohypogastric nerves in relation to an easily identifiable constant bony landmark, the anterior superior iliac spine (ASIS) in neonates and infants. The current ilioinguinal/iliohypogastric nerve block techniques were also evaluated from an anatomical perspective. METHOD: Dissections were performed on a sample of 25 infant and neonatal cadavers (mean weight = 2.2 kg; mean height = 45.6 cm). The distance from the ASIS to both the ilioinguinal and iliohypogastric nerves, on a line connecting the ASIS to the umbilicus was carefully measured using a digital caliper. Three techniques, commonly used in clinical practice, were simulated on the anatomical specimens. RESULT: The left and right ilioinguinal nerves were closer to the ASIS than previously described, i.e. 1.9 +/- 0.9 mm (mean +/- sd) and 2.0 +/- 0.7 mm, respectively. The mean distance from the left and right iliohypogastric nerves to the ASIS are 3.3 +/- 0.8 mm and 3.9 +/- 1.0 mm, respectively. CONCLUSIONS: We suggest that the high failure rate of the ilioinguinal/iliohypogastric nerve block in this age group could be due to lack of specific spatial knowledge of the anatomy of these nerves in infants and neonates. This cadaver-based study suggests an insertion point closer to the ASIS, approximately 2.5 mm (range: 1.0-4.9) from the ASIS on a line drawn between the ipsilateral ASIS and the umbilicus.

Cadaver↗
PubMed2004

Cricothyroidotomy: a clinical anatomy review.

The safe and successful performance of a cricothyroidotomy demands a working and yet specific knowledge of anatomy. An ignorance or misunderstanding of anatomy may result in failure or complications. The Educational Affairs Committee of the American Association of Clinical Anatomists has highlighted the importance of clinical anatomy for several invasive procedures. This review is building on their work and contribute further to the understanding of the anatomical framework, particularly the pitfalls and complications related to performing a cricothyroidotomy.

Cricoid Cartilage↗
PubMed2004

Lumbar puncture: anatomical review of a clinical skill.

The safe and successful performance of a lumbar puncture demands a working and specific knowledge of anatomy. Misunderstanding of anatomy may result in failure or complications. This review attempts to aid understanding of the anatomical framework, pitfalls, and complications of lumbar puncture. It includes special reference to 3D relationships, functional and imaging anatomy, and normal variation. Lumbar puncture is carried out for diagnostic and therapeutic purposes. Epidural and spinal anesthesia, for example, are common in obstetric practice and involve the same technique as diagnostic lumbar puncture except that the needle tip is placed in the epidural space in the former. The procedure is by no means innocuous and anatomical pitfalls include inability to find the correct entry site and lack of awareness of structures in relation to the advancing needle. Headache is the most common complication and it is important to avoid traumatic and dry taps, herniation syndromes, and injury to the conus medullaris. With a thorough knowledge of the contraindications, regional anatomy and rationale of the technique, and adequate prior skills practice, a lumbar puncture can be carried out safely and successfully.

Adult↗
PubMed1998

Riedel's lobe of the liver: fact or fiction?

Riedel's lobe should be considered in all patients undergoing cross-sectional imaging. It may harbor a lesion that might not be demonstrated unless the most inferior aspect of the liver is imaged. We have tried to identify the prevalence of Riedel's lobe in a series of patients with normal abdominopelvic computed tomographic (CT) findings. We reviewed the digital CT data of 105 patients, ages 20-89 years, to define the position of the liver in relation to the costal margin and the iliac crest. There were no significant differences in the prevalence of Riedel's lobe between sexes. The proportion of individuals in whom the most caudal margin of the liver was inferior to the most caudal costal margin was age-dependent and increased to 65% in the 50-59 age group. The craniocaudal dimension of the liver decreased with age (P < 0.02). Riedel's lobe appears to be a common variant of normal anatomy, its prevalence being dependent on age-related changes in liver size and skeletal shape.

Adult↗
PubMed1998

Intracranial course and relations of the hypoglossal nerve. An anatomic study.

This anatomic study describes the course and intracranial relations of the hypoglossal n. in 32 cadavers. The rootlets of the nerve emerged as a fan-shaped distribution (23.44%) or in two bundles (76.56%) and converged towards the hypoglossal canal in the subarachnoid space before piercing the duramater. In 76.57% of cases the rootlets pierced the dura mater in two separate apertures, less commonly through the same aperture (21.87%), and in rare cases through three individual apertures, as in one of our cases. The distance between the two apertures varied from 0.6 mm to 8.7 mm. Commonly, the two bundles converged together and left the skull through one foramen in the skull. However, in some cases (28.12%), the hypoglossal canal was divided in two by a small bony spicule. In 23.45% of cases the initial course of the posterior inferior cerebellar a. (PICA) passed between the two bundles of the hypoglossal n. before ascending towards the lateral border of the fourth ventricle.

Cadaver↗
PubMed1996

The abdominal subcutaneous tissue: computed tomographic, magnetic resonance, and anatomical observations.

We have studied the fasciae of the abdominal subcutaneous layer by analyzing axial CT images taken at a level immediately superior to the iliac crests in 20 adult female patients. The pattern of the fascial planes seen at this level was compared with those seen on MRI and dissected cadaveric sections. We have demonstrated a circumferential subcutaneous fascial plane that divides the subcutaneous fat into a single superficial fat compartment and a single deep fat compartment.

Abdominal Muscles↗
PubMed1996

Variant slips of psoas and iliacus muscles, with splitting of the femoral nerve.

In bilateral dissections of 68 cadavers, four examples were found unilaterally of variant slips of iliacus and psoas major muscles. In three of them the femoral nerve was pierced by the variant slip. One of these variants was a previously undocumented accessory slip of iliacus, originating from the iliolumbar ligament, passing inferiorly anterior to iliacus, and traversing the femoral nerve; its tendon split to be attached proximally to the lesser trochanter of the femur and distally to an unknown insertion. Such anomalies might cause tension on the femoral nerve resulting in referred pain to the hip and knee joints and to the lumbar dermatomes L2,3 and 4.

Femoral Nerve↗
PubMed1996

Computed tomographic observations on subcutaneous fat: implications for liposuction.

The anatomy of the abdominal subcutaneous tissues is discussed in the light of data obtained in 20 female patients examined on a modern computed tomographic system. We have shown that the superficial fascia, which separates the superficial and deep layers of subcutaneous fat, forms a continuous circumferential fascial plane. This superficial fascia, contrary to previous reports, does not appear to merge with the deep fascial plane around the external oblique muscle. The fat in the deep subcutaneous layer, bounded by the superficial fascia, is the target for liposuction techniques. The CT data have shown that about 50 percent of subcutaneous fat resides within this deep layer.

Adipose Tissue↗
PubMed1981

The node of Ranvier in early Wallerian degeneration: a freeze-fracture study.

Using the freeze-fracture technique, the sciatic nerve of the rat and rabbit was examined distally at 24 h after crush, with particular reference to the node of Ranvier and paranode. The paranodes, in the majority of myelinated fibres, showed a loss of the cytoplasmic circumferential bands and longitudinal columns and their associated membrane pores which characterise the normal Schwann cell surface. Axonal changes consisting of accumulations of axoplasmic organelles occurred at both the node and paranode. At the nodes large intramembraneous particles in the axolemma (E face) appeared unchanged. Nodal Schwann cell microvilli and paranodal myelin terminal loops were generally unaffected. The findings are discussed in terms of the decrease in amplitude of the action potential which occurs in early Wallerian degeneration.

Action Potentials↗
PubMed1980

Schwann cell plasma membrane changes induced by nerve crush. A freeze-fracture study.

Twenty-four hours after nerve crush, the Schwann cell plasma membrane and subjacent outer layer of Schwann cell cytoplasm were examined by freeze-fracture in myelinated fibres from the rat and rabbit sciatic nerves. The irregular circumferential bands and longitudinal columns of cytoplasm which characterise the surface of the normal Schwann cell were diminished or had disappeared. Concomitantly, the membrane pores (of micropinocytotic vesicles or caveolae) which are normally present on the bands and columns were also lost. The loss of these specialised features is discussed in terms of the onset of cell dedifferentiation in association with cell division. The Schwann cell plasma membrane acquired a new feature: deep impressions of adjacent collagen fibres, present particularly on the cytoplasmic bands and columns and presumed to be related to a transient increase in fibre diameter.

Animals↗
PubMedDate not supplied

Plasma membrane pores of the Schwann cell in Wallerian degeneration: a morphometric analysis.

Using the freeze-fracture technique, myelinated fibres were examined from the rabbit sciatic nerve at 48 h after a proximal nerve crush. Employing computer-aided morphometric techniques the distribution of Schwann cell plasma membrane pores was analysed. In both normal control and crushed nerves membrane pores were restricted to the cytoplasmic circumferential bands and longitudinal columns, which characterize the surface of the myelinated nerve fibre, and were absent from the flat plaque-like areas delimited by the bands and columns. In approximately half of the myelinated fibres from the crushed nerves there was a five-fold increase in the density of plasma membrane pores. This response of the Schwann cell was interpreted in terms of an increase in pinocytosis and related to regenerative phenomena in the peripheral nerve.

Animals↗