Δευτέρα, 15 Απριλίου 2019

Anatomy

Dacryocystography: From theory to current practice

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Swati Singh, Mohammad Javed Ali, Friedrich Paulsen

Abstract
Purpose

To provide a review and an update on dacryocystography (DCG) and its relevance in the current era.

Methods

The authors performed a PubMed search of all articles published in English on DCG, digital subtraction-DCG (DS-DCG), computed tomographic DCG (CT-DCG) and magnetic resonance-DCG (MR-DCG). Data analyzed include the indications, techniques, interpretations, complication and limitations.

Results

Dacryocystography has been used for illustrating the morphological and functional aspects of the lacrimal drainage system (LDS). Subtraction DCG provides the precise location of the alterations and acceptably delineates stenosis or an obstruction. Transit time for contrast into the nose varies widely across the studies. Low osmolality iodinated contrast media are tolerated well for DS-DCG and CT-DCG. However, normal saline either mixed with lidocaine or alone provided similar image quality as obtained with gadolinium for MR-DCG. CT-DCG provides useful information in complex orbitofacial trauma and lacrimal tumors. MR-DCG allows better 3D visualization of the LDS and dynamic functional evaluation. Sensitivity of CT-DCG and MR-DCG are mostly similar in identifying an LDS obstruction.

Conclusion

Various forms of DCGs can provide additional information to evaluate patients with maxillo-facial trauma, functional epiphora, suspected lacrimal sac diverticula, partial nasolacrimal duct obstruction, and lacrimal drainage tumors. Canaliculi and the membranous part of the nasolacrimal duct are not yet visualized in detail and further focused studies with advanced techniques are required.



Ultrastructure of the lacrimal drainage system in health and disease: A major review

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Mohammad Javed Ali, Friedrich Paulsen

Abstract
Purpose

To provide a systematic review of the literature on the ultrastructural findings of the lacrimal drainage system in healthy state and in few of the disorders studied so far.

Methods

The authors performed a PubMed search of all articles published with reference to electron microscopic features of the lacrimal drainage pathways. Data captured include demographics, study techniques, scanning or transmission electron microscopic features, presumed or confirmed interpretations and their implications. Specific emphasis was laid on addressing the lacunae and potential directions for future research.

Results

Ultrastructural studies have led to better understanding of the lacrimal drainage anatomy-physiology correlations. Cellular interactions between fibroblasts and lymphocytes could form a basis for pathogenesis of punctal stenosis. Ultrastructural characterization of peri-lacrimal cavernous bodies and changes in primary acquired nasolacrimal duct obstruction (PANDO) led to them being partly implicated in its etiopathogenesis. Electron microscopic characterization of the dacryolith core promises insights into their evolution. Ultrastructural tissue effects of mitomycin-C during a DCR surgery has provided potential evidence of its role in cases with high-risk of failure. Lacrimal stent biofilms are common but their clinical implications are currently uncertain.

Conclusion

Ultrastructural exploration of lacrimal drainage system so far has been limited and sparsely explored. The list of unexplored areas is exhaustive. There is a need for the lacrimal Clinician-Scientist to make themselves familiar with techniques and interpretation of electron microscopy to advance the ultrastructural frontier of this science.



Computed tomographic assessment of the lacrimal sac fossa in the Japanese population

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Tushar Sarbajna, Yasuhiro Takahashi, Ma. Regina Paula Valencia, Makoto Ito, Kunihiro Nishimura, Hirohiko Kakizaki

Abstract
Purpose

To analyze the morphology of the lacrimal sac fossa in the Japanese population using computed tomographic images.

Materials and methods

One-hundred-fifty-five Japanese patients diagnosed with unilateral orbital fracture were retrospectively reviewed. Measurements of the dimensions of the lacrimal sac fossa were taken on three anatomical planes (upper, middle, and lower planes) using a digital caliper/protractor tool.

Results

The mean maximum thickness of the maxillary bone at the upper, middle, and lower planes of the lacrimal sac fossa were 4.60 mm, 5.07 mm, and 6.30 mm, respectively. The midpoint thickness of the maxillary bone at each plane were 3.04 mm, 3.00 mm, and 2.17 mm, respectively. The lacrimal bone thickness at each plane were 1.13 mm, 1.13 mm, and 1.08 mm, respectively. The proportion of the lacrimal sac fossa comprising of the lacrimal bone at each plane were 39.00%, 42.05%, 38.92%, respectively. On the middle plane, the mean angle between the lacrimal bone and sagittal plane was 131.92°.

Conclusions

In Japanese patients, the proportion of the lacrimal bone on the lacrimal sac fossa tended to be of greater proportion compared to studies done on other races. The mean angle of the lacrimal sac fossa seemed to be comparatively high. These results indicate that performing an osteotomy during dacryocystorhinostomy could be relatively easier in the Japanese population compared to other races.



Flap valve of the heart foramen ovale revisited: macroscopic and histologic observations of human near-term fetuses

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Daisuke Suzuki, Ji Hyun Kim, Shunichi Shibata, Hitoshi Abe, Gen Murakami, José Francisco Rodríguez-Vázquez

Abstract

We assessed the flap valve of the foramen ovale (FO valve) by examining 30 hearts from human fetuses of gestational age 30–40 weeks. We dissected the hearts, examined their macroscopic morphology, and then prepared semiserial sagittal sections across the valve. Although the primary septum is expected to extend along the left atrial face, eight hearts had a superior rim of the fossa ovalis on the left atrial face that was too thick and high, so there was no smooth continuation with the valve. Moreover, three of these eight hearts each had a flap valve that was fused with a long and narrow plate arising from the caval orifice. Histological analysis indicated that 21 specimens each had a candidate primary septum that contained myocardium, although the left sinuatrial valve (LSAV) contained fibrous tissue, but little or no myocardium. In each of 17 hearts, a candidate primary septum was attached to the left atrial face of the fossa, and parts of the LSAV extended to and approached the right atrial face. However, seven of these 17 hearts each had a folded small primary septum. Another four of these 17 hearts each had an LSAV that extended widely to the fossa, and a candidate primary septum (which might be a remnant) attached to the left atrial side of the LSAV. These variations suggest that the LSAV makes a major contribution to the FO valve in some fetal hearts. Consequently, the fetal FO valve appears to have heterogeneous morphology and origin.



Anatomical considerations in endoscopic lacrimal surgery

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Saul N. Rajak, Alkis J. Psaltis

Abstract
Purpose

To provide a review of the anatomy of the lacrimal drainage system and lateral wall of the nose pertaining to endoscopic dacryocystorhinostomy.

Methods

The authors performed a PubMed search of articles published pertaining to the anatomy of the lateral wall of the nose and the anatomy of endonasal and external dacryocystorhinostomy surgery.

Results

The article covers the regional surface and surgical anatomy for endoscopic dacryocystorhinostomy (DCR), including the maxillary line, middle turbinate, agger nasi air cell, lacrimal sac and fossa and the upper portion of the nasolacrimal drainage system. It also explores the dimensions and location of bony ostium formation to ensure full exposure and marsupialisation of the lacrimal sac. Finally, it covers the anatomy of potential complications of endoscopic DCR surgery including penetration of the skull base and orbit, inadvertent entry to the maxillary sinus and breach of the skin.

Conclusion

A good understanding of the anatomy of the lacrimal drainage system and the lateral wall of the nose will increase the likelihood of successful surgery and minimize the risk of complications and damage to neighbouring structures such as the orbit and skull base.



The large intestine from fetal period to adulthood and its impact on the course of colonoscopy

Publication date: July 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 224

Author(s): Slawomir Wozniak, Tomasz Pytrus, Christopher Kobierzycki, Krzysztof Grabowski, Friedrich Paulsen

Abstract

The human large intestine in the living adult has a total length of about 1300 mm, ranging from 1100 to 2108 mm. The development of the gut continues after birth, up to the age 4–5. The large intestine ascends at the beginning in the right abdominal quadrant, then it traverses the abdominal cavity, and finally it descends to the anus. The left and right colic flexures are the basic flexions between the transverse, ascending and descending colon, respectively. Additionally, there are secondary bendings between intestinal segments. The angles between the neighbouring parts can vary between examined subjects. Most of the angulations can be found in the transverse (range 2–9) and sigmoid colon (range 1–9), making them the most troublesome parts to pass with a colonoscope.

Colonoscopy (usually performed in the left lateral or supine position) is one of the most important examination of the large intestine mucus membrane. During this procedure the endoscope is passed through the colon into the cecum or terminal ilium. The individual anatomical features (tortuosity, supernumerary loops and elongation) may slow down or interfere with the progress of the scope.

We summarize current knowledge on the human large intestine from the fetal period to adulthood and carve out some aspects that are currently less known to colonoscopists.



Lacrimal drainage anatomy in the Japanese population

Publication date: May 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 223

Author(s): Ma. Regina Paula Valencia, Yasuhiro Takahashi, Munekazu Naito, Takashi Nakano, Hiroshi Ikeda, Hirohiko Kakizaki

Abstract
Purpose

The aim of this study is to provide a comprehensive and clinically relevant review of the lacrimal drainage anatomy in the Japanese population.

Methods

A thorough search on the lacrimal drainage anatomy in the Japanese population was performed using PubMed and Ichushi Web, which is managed by the Japan Medical Abstracts Society, for related studies up to December 2018. Published books on the same topic were also reviewed. Data from all articles and book chapters were reviewed, analyzed, and incorporated in this review.

Results

This review presents the subparts of the lacrimal drainage anatomy in a chronological manner, from proximal to distal. The location, dimensions, position or angle, histology (with some reference to the essential clinical functions and physiology of the lacrimal drainage system) are described in this review.

Conclusions

Understanding lacrimal drainage anatomy in the Japanese population is essential to provide insight as to how it is important to consider patients as individuals, with unique and specific anatomies, and uphold a patient-specific approach.



The history of anatomical research of lymphatics — From the ancient times to the end of the European Renaissance

Publication date: May 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 223

Author(s): Regina Irschick, Claudia Siemon, Erich Brenner

Abstract

Very often, descriptions of the scientific discovery of the lymphatic system start with Gaspare Aselli, probably because of his so captivating account. Nevertheless, there was prior and even very old evidence of the lymphatic vessels, which was of course known to Aselli himself, as he cited most of these antique references.

In fact, the first insights were contributed by the Hippocratic School. The Alexandrian School added quite a lot but unfortunately most of that knowledge is not extant and can only be appreciated by translations or citations by other authors such as Galen.

The 'dark' middle ages did not add to the anatomical knowledge of the lymphatics, and only the rise of the Renaissance brought new insights. Even at that time, Aselli was not the first to identify at least some components of the lymphatic system, but he was actually the first to present a proper account in a book dedicated to the "lacteal veins". Afterwards the interest rose enormously and cumulated in one of the first priority – or plagiarism – disputes, the Rudbeck–Bartholin feud. Surprisingly, William Harvey, the discoverer of the systemic blood circulation, ignored, at least in part, the progress of the discoveries in lymphatic circulation.

This narrative review tries to summarize the major contributions to the anatomical knowledge of the lymphatic system from the ancient times up to the end of the European Renaissance.



Deep lymphatic anatomy of the upper limb: An anatomical study and clinical implications

Publication date: May 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 223

Author(s): Chuan-Xiang Ma, Wei-Ren Pan, Zhi-An Liu, Fan-Qiang Zeng, Zhi-Qiang Qiu, Mei-Ying Liu

Abstract
Background

The deep and perforating lymphatic anatomy of the upper limb still remains the least described in medical literature.

Materials and Methods

Six upper limbs with the axillary tissue were harvested from three unembalmed human cadavers amputated at the shoulder joint. A small amount of 6% hydrogen peroxide was employed to detect the lymphatic vessels around the deep palmar arch, radial and ulnar neurovascular bundles. A 30-gauge needle was inserted into the vessels and they were injected with a barium sulphate compound. Each specimen was dissected, photographed and radiographed to demonstrate deep lymphatic distribution of the upper limb.

Results

Continuing from the deep lymph vessels of the hand, single or multiple deep collecting lymph vessels have been found along the radial, ulnar, anterior and posterior interosseous neurovascular bundles in the forearm, brachial and deep branchial neurovascular bundles in the upper arm. During their courses, lymph nodes were found setting in the trunk of the radial, ulnar and brachial lymph vessels near or in the cubital fossa, and in the axillar. Perforating lymph vessels have been found near the wrist and in the cubital fossa, which linked the superficial and deep lymph vessels. The direction of lymphatic drainage was from the deep to superficial or superficial to deep vessels.

Conclusion

The deep lymphatic anatomy of the upper limb has been described. The results will provide an anatomical basis for clinical management, educational reference and scientific research.



Radiologist's views on anatomical knowledge amongst junior doctors and the teaching of anatomy in medical curricula

Publication date: May 2019

Source: Annals of Anatomy - Anatomischer Anzeiger, Volume 223

Author(s): Gerard W. O'Keeffe, Shane Davy, Denis S. Barry

Abstract

Reduced teaching resources, increasing student numbers and congested medical curricula have led to reports of inadequate anatomical knowledge among newly qualified doctors, placing scrutiny on pre-clinical education. We wished to gauge the opinions of practicing radiologists on undergraduate anatomy education. Members of the Irish Faculty of Radiologists were invited to complete a questionnaire based on anatomy teaching practices, its relevance and the standards of anatomical knowledge at graduation. Out of 67 respondents, 69% were of senior grade, with the majority working in diagnostic radiology. Respondents universally agreed that anatomy is central to radiology; however, decade of graduation significantly influenced radiologist's level of satisfaction with their anatomical knowledge at the start of their training. Fifty percent believed that the cadaver should remain the cornerstone of anatomy education. The vast majority of radiologists agreed that radiology and anatomy should be taught in tandem during pre-clinical training to better prepare students for clinical practice. Practicing radiologists believed they were best positioned to deliver radiology-based anatomy teaching. CT and MRI respectively were proposed as the preferred imaging modalities for teaching anatomy, although free comments showed varied opinion on how radiology and cadaveric anatomy should be integrated. Radiologists were also concerned with the anatomical knowledge of the junior doctor. This study may add to the debate concerning the vertical integration of anatomy in medical education and may help inform the delivery of radiology in the anatomy curriculum.



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