Microsurgical Anatomy of the Precuneal Artery: Does It Really Exist? Clarifying an Ambiguous Vessel Under the Microscope

2015 ◽  
Vol 12 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Ioannis N Mavridis ◽  
Theodosis Kalamatianos ◽  
Christos Koutsarnakis ◽  
George Stranjalis
Keyword(s):  
Significant Variation ◽  
Posterior Cerebral Artery ◽  
Average Distance ◽  
Microsurgical Anatomy ◽  
Operating Microscope ◽  
Elderly Individuals ◽  
The Right ◽  
Artery Branch ◽  
Formalin Fixed ◽  
Complex Origin

Abstract BACKGROUND The ambiguous term precuneal artery (PA) has several synonyms and anatomic definitions. OBJECTIVE To examine the arteries of the precuneus and describe the PA and its branching pattern. We defined the PA as the principal arterial supplier of the precuneus. METHODS Twenty formalin-fixed, colored latex–injected cadaveric heads were studied with the aid of an operating microscope and microsurgical instrumentation. After removal of the cerebrum from the cranial vault, we examined this vessel's anatomy. Anatomic features of the PA were investigated and assessed in relation to demographic and anthropometric variables. RESULTS The PA was always a pericallosal artery branch and, more specifically, the superior internal parietal artery (SIPA) in 86.84%, the inferior internal parietal artery in 2.63%, and their common stem in 10.53% of specimens. Anastomosing interhemispheric branches between the PAs were present in 20% of cases. Compared with the right PA, the left anastomosed nearly 3 times more often with the ipsilateral posterior cerebral artery. The average distance of the PA's origin from the posterior limit of the splenium was shown to be 9.4 mm longer in elderly individuals compared with younger ones. CONCLUSION The term PA complex (rather than PA) can better describe the principal arterial supplier of the precuneus, and the SIPA, inferior internal parietal artery, and their common stem were shown as the 3 contributing arteries, with the SIPA predominating. The average distance of the PA complex origin from the splenium's posterior limit shows significant variation with respect to age.

Endoscope or Microscope?

2007 ◽  
Vol 106 (4) ◽  
pp. 730-731
Author(s):  
William T. Couldwell
Keyword(s):  
Nasal Septum ◽  
Transsphenoidal Approach ◽  
Operating Microscope ◽  
Endonasal Approach ◽  
Panoramic View ◽  
Extended Transsphenoidal Approach ◽  
The Right ◽  
Formalin Fixed

Object. The authors compare the views afforded by the operating microscope and the endoscope in the direct endonasal extended transsphenoidal approach to the sellar, suprasellar, and parasellar regions. Methods. Five formalin-fixed, silicone-injected adult cadaveric heads were studied. A direct endonasal transsphenoidal approach was performed via the right nostril, pushing aside the nasal septum. The approach was performed with the microscope first, then with the endoscope. For each step (sellar, suprasellar, and clival), the exposure afforded by direct microscopic view was measured and then compared with that obtained using the endoscope. The direct endonasal approach provides a slightly off-midline view. Although the microscope provides an adequate view of the midline structures and part of the contralateral parasellar areas, the addition of the endoscope allows for a more panoramic view and permits widening of the approach in all directions. Conclusions. An adequate exposure of the sellar, suprasellar, and infrasellar/upper clival regions can be achieved via a simple, direct endonasal approach. From a direct endonasal route, there is a preferential visualization of the structures contralateral to the approach. The endoscope affords a more panoramic view that extends the area covered by the operating microscope.

Comparison between the microscope and endoscope in the direct endonasal extended transsphenoidal approach: anatomical study

2006 ◽  
Vol 104 (3) ◽  
pp. 419-425 ◽  
Author(s):  
Domenico Catapano ◽  
Chris A. Sloffer ◽  
Giorgio Frank ◽  
Ernesto Pasquini ◽  
Vincenzo A. D’Angelo ◽  
...  
Keyword(s):  
Nasal Septum ◽  
Anatomical Study ◽  
Transsphenoidal Approach ◽  
Operating Microscope ◽  
Endonasal Approach ◽  
Panoramic View ◽  
Extended Transsphenoidal Approach ◽  
The Right ◽  
Formalin Fixed

Object The authors compare the views afforded by the operating microscope and the endoscope in the direct endonasal extended transsphenoidal approach to the sellar, suprasellar, and parasellar regions. Methods Five formalin-fixed, silicone-injected adult cadaveric heads were studied. A direct endonasal transsphenoidal approach was performed via the right nostril, pushing aside the nasal septum. The approach was performed with the microscope first, then with the endoscope. For each step (sellar, suprasellar, and clival), the exposure afforded by direct microscopic view was measured and then compared with that obtained using the endoscope. The direct endonasal approach provides a slightly off-midline view. Although the microscope provides an adequate view of the mid-line structures and part of the contralateral parasellar areas, the addition of the endoscope allows for a more panoramic view and permits widening of the approach in all directions. Conclusions An adequate exposure of the sellar, suprasellar, and infrasellar/upper clival regions can be achieved via a simple, direct endonasal approach. From a direct endonasal route, there is a preferential visualization of the structures contralateral to the approach. The endoscope affords a more panoramic view that extends the area covered by the operating microscope.

scholarly journals Microsurgical anatomy of the arterial basket of the conus medullaris

2015 ◽  
Vol 22 (6) ◽  
pp. 672-676 ◽  
Author(s):  
Nikolay L. Martirosyan ◽  
M. Yashar S. Kalani ◽  
G. Michael Lemole ◽  
Robert F. Spetzler ◽  
Mark C. Preul ◽  
...  
Keyword(s):  
Blood Supply ◽  
Vascular Malformations ◽  
Conus Medullaris ◽  
Microsurgical Anatomy ◽  
Arteriovenous Fistulas ◽  
Mean Diameter ◽  
The Mean ◽  
Posterior Spinal Arteries ◽  
The Right ◽  
Formalin Fixed

OBJECT The arterial basket of the conus medullaris (ABCM) consists of 1 or 2 arteries arising from the anterior spinal artery (ASA) and circumferentially connecting the ASA and the posterior spinal arteries (PSAs). The arterial basket can be involved in arteriovenous fistulas and arteriovenous malformations of the conus. In this article, the authors describe the microsurgical anatomy of the ABCM with emphasis on its morphometric parameters and important role in the intrinsic blood supply of the conus medullaris. METHODS The authors performed microsurgical dissections on 16 formalin-fixed human spinal cords harvested within 24 hours of death. The course, diameter, and branching angles of the arteries comprising the ABCM were then identified and measured. In addition, histological sections were obtained to identify perforating vessels arising from the ABCM. RESULTS The ASA tapers as it nears the conus medullaris (mean preconus diameter 0.7 ± 0.12 mm vs mean conus diameter 0.38 ± 0.08 mm). The ASA forms an anastomotic basket with the posterior spinal artery (PSA) via anastomotic branches. In most of the specimens (n= 13, 81.3%), bilateral arteries formed connections between the ASA and PSA. However, in the remaining specimens (n= 3, 18.7%), a unilateral right-sided anastomotic artery was identified. The mean diameter of the right ABCM branch was 0.49 ± 0.13 mm, and the mean diameter of the left branch was 0.53 ± 0.14 mm. The mean branching angles of the arteries forming the anastomotic basket were 95.9° ± 36.6° and 90° ± 34.3° for the right- and left-sided arteries, respectively. In cases of bilateral arterial anastomoses between the ASA and PSA, the mean distance between the origins of the arteries was 4.5 ± 3.3 mm. Histological analysis revealed numerous perforating vessels supplying tissue of the conus medullaris. CONCLUSIONS The ABCM is a critical anastomotic connection between the ASA and PSA, which play an important role in the intrinsic blood supply of the conus medullaris. The ABCM provides an important compensatory function in the blood supply of the spinal cord. Its involvement in conus medullaris vascular malformations makes it a critical anatomical structure.

Neurospect Findings in Patients Exposed to Neurotoxic Chemicals

1994 ◽  
Vol 10 (4-5) ◽  
pp. 561-571
Author(s):  
Gunnar Heuser ◽  
Ismael Mena ◽  
Francisca Alamos
Keyword(s):  
Elderly Patients ◽  
Qualitative Analysis ◽  
Right Hemisphere ◽  
Young Patients ◽  
Chronic Fatigue ◽  
Psychiatric Symptomatology ◽  
Elderly Individuals ◽  
Parietal Lobes ◽  
The Right ◽  
The Brain

Exposures to neurotoxic chemicals such as pesticides, glues, solvents, etc. are known to induce neurologic and psychiatric symptomatology. We report on 41 patients 16 young patients (6 males, 10 females, age 34 8 yrs.) and 25 elderly patients (9 males, 16 females, age 55 7 yrs). Fifteen of them were exposed to pesticides, and 29 to solvents. They were studied with quantitative and qualitative analysis of regional cerebral bood flow (rCBF), performed with 30 mCi of Xe-133 by inhalation, followed by 30 mCi of Tc-HMPAO given intravenously. Imaging was performed with a brain dedicated system, distribution of rCBF was assessed with automatic ROI definition, and HMPAO was normalized to maximal pixel activity in the brain. Results of Xe rCBF are expressed as mean and S.D. in ml/min/100g, and HMPAO as mean and S.D. uptake per ROI, and compared with age-matched controls 10 young and 20 elderly individuals. Neurotoxics HMPAO Uptake Young Elderly R. Orbital frontal R. Dorsal frontal .70 .66 p < 0.05 R. Temporal .64 p < 0.001 R. Parietal .66 .66 We conclude that patients exposed to chemicals present with diminished CBF, worse in the right hemisphere, with random presentation of areas of hypoperfusion, more prevalent in the dorsal frontal and parietal lobes. These findings are significantly different from observations in patients with chronic fatigue and depression, suggesting primary cortical effect, possibly due to a vasculitis process.

scholarly journals The Microsurgical Relationships between Internal Carotid-Posterior Communicating Artery Aneurysms and the Skull Base

2017 ◽  
Vol 79 (05) ◽  
pp. 427-436 ◽  
Author(s):  
Noritaka Komune ◽  
Ryosuke Tsuchimochi ◽  
Yasutoshi Kai ◽  
Kenichi Matsumoto ◽  
Sei Haga ◽  
...  
Keyword(s):  
Skull Base ◽  
Clinical Characteristics ◽  
Internal Carotid ◽  
Posterior Communicating Artery ◽  
Microsurgical Anatomy ◽  
Anterior Clinoid Process ◽  
Anterior Clinoidectomy ◽  
Close Relationship ◽  
Anatomical Relationship ◽  
Formalin Fixed

Objective This study aimed to review the anatomical and clinical characteristics of internal carotid-posterior communicating artery (IC-PC) aneurysms, especially those located close to the skull base. Methods The microsurgical anatomy around the posterior communicating artery (PComA) was examined in a dry skull and five formalin-fixed human cadaveric heads. The clinical characteristics of 37 patients with 39 IC-PC aneurysms, who were treated microsurgically between April 2008 and July 2016, were retrospectively reviewed. Results The anterior clinoid process (ACP), as well as the anterior petroclinoidal dural fold (APF), which forms part of the oculomotor triangle, are closely related to the origin of the PComA. Among the 39 IC-PC aneurysms, anterior clinoidectomy was performed on 4 (10.3%) and a partial resection of the APF was performed on 2 (5.1%). Both of these aneurysms projected inferior to the tentorium, or at least part of the aneurysm's dome was inferior to the tentorium. Conclusion Proximally located IC-PC aneurysms have an especially close relationship with the ACP and APF. We should be familiar with the anatomical relationship between IC-PC aneurysms and the structures of the skull base to avoid hazardous complications.

Location of Vertical Limb of Extensile Lateral Calcaneal Approach and Risk of Injury of the Calcaneal Branch of Peroneal Artery

2018 ◽  
Vol 40 (2) ◽  
pp. 224-230 ◽  
Author(s):  
Norachart Sirisreetreerux ◽  
Paphon Sa-ngasoongsong ◽  
Noratep Kulachote ◽  
Theerachai Apivatthakakul
Keyword(s):  
Achilles Tendon ◽  
Average Distance ◽  
Skin Flap ◽  
Wound Complication ◽  
Calcaneal Fracture ◽  
Peroneal Artery ◽  
Lateral Edge ◽  
Vertical Incision ◽  
Fresh Frozen ◽  
The Right

Background: The extensile lateral calcaneal approach is a standard method for accessing a joint depression calcaneal fracture. However, the operative wound complication rate is high. Previous studies showed a calcaneal branch of the peroneal artery contributing to the calcaneal flap blood supply. This study focuses on the location of the vertical limb in this approach correlating to the aforementioned artery and flap perfusion. Methods: Ten pairs of fresh-frozen cadaveric lower extremities were used. Extensile lateral calcaneal approach (ELCA) was carried out on both calcanei, where the vertical limb was placed at the line between the posterior border of lateral malleolus and lateral edge of the Achilles tendon for the right side (standard ELCA; sELCA) and at the lateral edge of the Achilles tendon for the left side (modified ELCA; mELCA). The identified vessel in the vertical limb incision was ligated and cut, and the horizontal limb of the incision was carried out as usual. After completion of flap elevation, 80°C water was injected into the popliteal vessel. In addition, thermal images were taken pre- and postinjection. Dye was injected subsequently, and perfusion was recorded in video format. Results: Mean pre- and postinjection skin flap temperature difference was significantly higher in mELCA (5.36°C vs 0.72°C, P = .0002). Dye perfusion patterns were significantly better in mELCA ( P = .0013). The calcaneal branch of peroneal artery was found in the vertical incision in 9 of 10 sELCA, with average distance 22.04 mm anterior to the calcaneal tuberosity and 8.22 mm proximal to superior border of the calcaneus, whereas one was found in mELCA, in which perfusion tests still appeared normal. Conclusion: The vertical limb of incision during extensile lateral calcaneal approach should be placed at the lateral edge of the Achilles tendon to avoid injuring the calcaneal branch of peroneal artery, which supplies the lateral calcaneal flap. However, further clinical research might be needed to confirm the results of this study. Clinical relevance: This study demonstrates a likely safest position for the proper incision for exposing the lateral calcaneus.

Level I to III craniofacial approaches based on Barrow classification for treatment of skull base meningiomas: surgical technique, microsurgical anatomy, and case illustrations

2011 ◽  
Vol 30 (5) ◽  
pp. E5 ◽  
Author(s):  
Emel Avcı ◽  
Erinç Aktüre ◽  
Hakan Seçkin ◽  
Kutluay Uluç ◽  
Andrew M. Bauer ◽  
...  
Keyword(s):  
Surgical Technique ◽  
Skull Base ◽  
Surgical Anatomy ◽  
Microsurgical Anatomy ◽  
Middle Point ◽  
The Mean ◽  
The Right ◽  
Skull Base Meningiomas ◽  
Supraorbital Foramen ◽  
Ethmoidal Foramen

Object Although craniofacial approaches to the midline skull base have been defined and surgical results have been published, clear descriptions of these complex approaches in a step-wise manner are lacking. The objective of this study is to demonstrate the surgical technique of craniofacial approaches based on Barrow classification (Levels I–III) and to study the microsurgical anatomy pertinent to these complex craniofacial approaches. Methods Ten adult cadaveric heads perfused with colored silicone and 24 dry human skulls were used to study the microsurgical anatomy and to demonstrate craniofacial approaches in a step-wise manner. In addition to cadaveric studies, case illustrations of anterior skull base meningiomas were presented to demonstrate the clinical application of the first 3 (Levels I–III) approaches. Results Cadaveric head dissection was performed in 10 heads using craniofacial approaches. Ethmoid and sphenoid sinuses, cribriform plate, orbit, planum sphenoidale, clivus, sellar, and parasellar regions were shown at Levels I, II, and III. In 24 human dry skulls (48 sides), a supraorbital notch (85.4%) was observed more frequently than the supraorbital foramen (14.6%). The mean distance between the supraorbital foramen notch to the midline was 21.9 mm on the right side and 21.8 mm on the left. By accepting the middle point of the nasofrontal suture as a landmark, the mean distances to the anterior ethmoidal foramen from the middle point of this suture were 32 mm on the right side and 34 mm on the left. The mean distance between the anterior and posterior ethmoidal foramina was 12.3 mm on both sides; the mean distance between the posterior ethmoidal foramen and distal opening of the optic canal was 7.1 mm on the right side and 7.3 mm on the left. Conclusions Barrow classification is a simple and stepwise system to better understand the surgical anatomy and refine the techniques in performing these complex craniofacial approaches. On the other hand, thorough anatomical knowledge of the midline skull base and variations of the neurovascular structures is crucial to perform successful craniofacial approaches.

scholarly journals Anatomical Variations of the Recurrent Laryngeal Nerve and Implications for Injury Prevention during Surgical Procedures of the Neck

Diagnostics ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 670
Author(s):  
Alison M. Thomas ◽  
Daniel K. Fahim ◽  
Jickssa M. Gemechu
Keyword(s):  
Recurrent Laryngeal Nerve ◽  
Surgical Procedures ◽  
Anatomical Variations ◽  
Laryngeal Nerve ◽  
Inferior Thyroid Artery ◽  
Branching Pattern ◽  
The Right ◽  
Relationship Of ◽  
Intrinsic Laryngeal Muscles ◽  
Formalin Fixed

Accurate knowledge of anatomical variations of the recurrent laryngeal nerve (RLN) provides information to prevent inadvertent intraoperative injury and ultimately guide best clinical and surgical practices. The present study aims to assess the potential anatomical variability of RLN pertaining to its course, branching pattern, and relationship to the inferior thyroid artery, which makes it vulnerable during surgical procedures of the neck. Fifty-five formalin-fixed cadavers were carefully dissected and examined, with the course of the RLN carefully evaluated and documented bilaterally. Our findings indicate that extra-laryngeal branches coming off the RLN on both the right and left side innervate the esophagus, trachea, and mainly intrinsic laryngeal muscles. On the right side, 89.1% of the cadavers demonstrated 2–5 extra-laryngeal branches. On the left, 74.6% of the cadavers demonstrated 2–3 extra-laryngeal branches. In relation to the inferior thyroid artery (ITA), 67.9% of right RLNs were located anteriorly, while 32.1% were located posteriorly. On the other hand, 32.1% of left RLNs were anterior to the ITA, while 67.9% were related posteriorly. On both sides, 3–5% of RLN crossed in between the branches of the ITA. Anatomical consideration of the variations in the course, branching pattern, and relationship of the RLNs is essential to minimize complications associated with surgical procedures of the neck, especially thyroidectomy and anterior cervical discectomy and fusion (ACDF) surgery. The information gained in this study emphasizes the need to preferentially utilize left-sided approaches for ACDF surgery whenever possible.

scholarly journals Microsurgical Treatment of Posterior Cerebral Artery Aneurysm (P2P Segment): Case Report and Review of the Literature

2018 ◽  
Vol 37 (04) ◽  
pp. 343-348
Author(s):  
Lucas Meguins ◽  
Antônio Spotti ◽  
Jean de Oliveira ◽  
Carlos Pereira ◽  
Ronaldo Fernandes ◽  
...  
Keyword(s):  
Case Report ◽  
Cerebral Artery ◽  
Posterior Cerebral Artery ◽  
Artery Aneurysm ◽  
Saccular Aneurysm ◽  
Neurological Deficits ◽  
Uneventful Recovery ◽  
Cerebral Peduncle ◽  
Vast Number ◽  
The Right

Introduction Aneurysms of the posterior cerebral artery (PCA) represent ∼ 1% of all intracranial aneurysms and usually present with subarachnoid hemorrhage. Objective The aim of the present study is to describe the case of an adult man presenting a saccular aneurysm of the right PCA at the posterior half of the postcommunicating (P2P) segment, and to discuss the technical nuances of the approach and of the clipping process. Case Report An investigation of a chronic headache in a 55-year-old man found a saccular aneurysm located just posterior to the most lateral portion of the right cerebral peduncle. A digital subtraction arteriography revealed a 7.8 mm × 5.6 mm × 4.8 mm posterior-medial projecting aneurysm of the right PCA at the P2P segment. A subtemporal approach was performed with partial aspiration of the right parahippocampal gyrus for a better exposure of the vascular structures. A proximal temporary occlusion of the PCA was performed at the anterior half of the postcommunicating P2A segment. The aneurysm was clipped with two semi-curved clips. The patient presented an uneventful recovery and was discharged from the hospital on the third postoperative day without any additional neurological deficits. Conclusion Aneurysms of the PCA are an uncommon vascular disease that challenges the ability of the neurosurgeons due to their many anatomical nuances, to their vast number of perforators, and to the risk of bleeding. However, the operative management of aneurysms of the PCA is technically feasible, safe and effective when performed respecting microsurgical principles.

Sign in / Sign up

Export Citation Format

Share Document