Joao Flavio Nogueira Junior, Iulo Barauna, Diego Rodrigo Hermann, Ronaldo dos Reis Americo, Raquel Garcia Stamm, Aldo Cassol Stamm

Sao Paulo ENT Center - Professor Edmundo Vasconcelos Hospital - Sao Paulo, Brazil

1- 3D Image: Material used for dissections2- Temporal Bone prepared for dissection

The profound and detailed knowledge of the anatomy of the temporal bone is a primordial point for the otologist. This end is gotten through exhausting dissection of temporal bones, assisted surgical training and with surgical experiences acquired along the years. For the surgeon in formation, the use of books and manuals of dissection sometimes don't allow the understanding of the complex structures as recesses and small structures of the ear and mastoid. We will show in this work the use of Stereoscopic three-dimensional (3D) images of the temporal bone for teaching purposes and documentation, detailing the acquisition method and processing of images.The use of 3D steroscopic images was shown to be an applicable,easily and useful method applicable in transmission of anatomical knowledge of otologic surgery in our center.

The profound and detailed knowledge of the anatomy of the temporal bone is a primordial point for the otologist. This end is gotten through exhausting dissection of temporal bones, assisted surgical training and with surgical experiences acquired along the years. For the surgeon in formation, the use of books and manuals of dissection sometimes don't allow the understanding of the complex structures as recesses and small structures of the ear and mastoid. We will show in this work the use of Stereoscopic three-dimensional (3D) images of the temporal bone for teaching purposes and documentation, detailing the acquisition method and processing of images.The use of 3D steroscopic images was shown to be an applicable,easily and useful method applicable in transmission of anatomical knowledge of otologic surgery in our center.

ABSTRACTABSTRACT

The anatomy of the human temporal bone is considered to be amongst the most complex structures in the body. Critical nervous, vascular and another structures are closely related to each other, often by only a few millimeters. An understanding of complex systems such as the transport of sound, facial nerve connections and the structures of the Optic Capsule are an important part of otologic surgery.Long training periods, exhaustive temporal bone dissection and surgical observation have traditionally formed the basis for education. Residents in our training program have had difficultly, at some stage during their education, in comprehending the anatomy when shown through only through theoretical anatomy lectures. Three dimensional (3D) images may allow a better understanding of the important relationships among the structures within the temporal bone.

The anatomy of the human temporal bone is considered to be amongst the most complex structures in the body. Critical nervous, vascular and another structures are closely related to each other, often by only a few millimeters. An understanding of complex systems such as the transport of sound, facial nerve connections and the structures of the Optic Capsule are an important part of otologic surgery.Long training periods, exhaustive temporal bone dissection and surgical observation have traditionally formed the basis for education. Residents in our training program have had difficultly, at some stage during their education, in comprehending the anatomy when shown through only through theoretical anatomy lectures. Three dimensional (3D) images may allow a better understanding of the important relationships among the structures within the temporal bone.

INTRODUCTIONINTRODUCTION

a) Demonstrate stereoscopic 3D images of the human temporal bone. b) Demonstrate 3D anatomical image applications in an ENT resident training program.

a) Demonstrate stereoscopic 3D images of the human temporal bone. b) Demonstrate 3D anatomical image applications in an ENT resident training program.

OBJECTIVESOBJECTIVES

Fourteen (14) temporal bones were dissected in the Anatomical Laboratory of the Professor Edmundo Vasconcelos Hospital, São Paulo-Brazil. Two (2) were selected in order to obtain photographic examples of surgical landmarks. The cadaveric specimens selected, by the senior authors, featured important surgically relevant anatomical features. Two (2) digital images of each surgical landmark were taken with a digital camera (SONY Cyber-Shot DSC-W50). The anatomical landmarks choosen were those found in a logical “step-by-step” temporal bone dissection including structures in the middle ear such ossicles, facial nerve and fallopian canal, vestibular and cochlear windows. Two different photos were captured moving the camera between the pictures in an horizontal plane (62 to 66 mm). The camera was connected directly to the operative microscope for acquisition. The images were edited with Adobe Photoshop version 8.0 and processed with Callipygian 3D version 2.9.

High quality 3D images were produced (figs 1,2 and 4). The images should be acquired with a relevant background for the better spatial relationship and depth perception of the surgical field. Some colors, mainly red, was poorly translated in the 3D images. However, this was partly expected due to the employed technique (1).

This is a result of the filters used in the anaglyph method, mainly red and blue.

Fourteen (14) temporal bones were dissected in the Anatomical Laboratory of the Professor Edmundo Vasconcelos Hospital, São Paulo-Brazil. Two (2) were selected in order to obtain photographic examples of surgical landmarks. The cadaveric specimens selected, by the senior authors, featured important surgically relevant anatomical features. Two (2) digital images of each surgical landmark were taken with a digital camera (SONY Cyber-Shot DSC-W50). The anatomical landmarks choosen were those found in a logical “step-by-step” temporal bone dissection including structures in the middle ear such ossicles, facial nerve and fallopian canal, vestibular and cochlear windows. Two different photos were captured moving the camera between the pictures in an horizontal plane (62 to 66 mm). The camera was connected directly to the operative microscope for acquisition. The images were edited with Adobe Photoshop version 8.0 and processed with Callipygian 3D version 2.9.

High quality 3D images were produced (figs 1,2 and 4). The images should be acquired with a relevant background for the better spatial relationship and depth perception of the surgical field. Some colors, mainly red, was poorly translated in the 3D images. However, this was partly expected due to the employed technique (1).

This is a result of the filters used in the anaglyph method, mainly red and blue.

MATERIAL, METHODS AND RESULTSMATERIAL, METHODS AND RESULTS

Tridimensional images has been advocated for a better undestanding of selected anatomic structures (5,6,7,8,9,10) during medical training. A review of the medical literature reveals several studies/reports of similar use of tridimensional images to facilitate anatomy education (9,10). In the last decade, increasing difficulties in obtaining cadaveric specimens for dissection has limited many residents’ training opportunites. At our intitution, we attempted to compensate for this decreasing cadaveric exposure with more didactic lessons but had limited success. The use of tridimensional images in conjunction with our lessons achieved greater comprehension in our theoretical classes. There were minimal difficulties in capturing and generating the images. Standard consumer digital cameras are suitable. The Callipygian 3D version 2.9. is a freeware program and can be acquired easily from http://www.callipygian.com/3D/

Among the methods used for generating stereoscopic 3D images, a simple and popular technique is the analogical method (1) . This was employed in our work and consists of overlaying two digital images of the same structure coloring the images (figure 6) then using a special filter of a similar color used for each image prior to 3D processing (figure 7), usually red and blue (1,2) .

Tridimensional images has been advocated for a better undestanding of selected anatomic structures (5,6,7,8,9,10) during medical training. A review of the medical literature reveals several studies/reports of similar use of tridimensional images to facilitate anatomy education (9,10). In the last decade, increasing difficulties in obtaining cadaveric specimens for dissection has limited many residents’ training opportunites. At our intitution, we attempted to compensate for this decreasing cadaveric exposure with more didactic lessons but had limited success. The use of tridimensional images in conjunction with our lessons achieved greater comprehension in our theoretical classes. There were minimal difficulties in capturing and generating the images. Standard consumer digital cameras are suitable. The Callipygian 3D version 2.9. is a freeware program and can be acquired easily from http://www.callipygian.com/3D/

Among the methods used for generating stereoscopic 3D images, a simple and popular technique is the analogical method (1) . This was employed in our work and consists of overlaying two digital images of the same structure coloring the images (figure 6) then using a special filter of a similar color used for each image prior to 3D processing (figure 7), usually red and blue (1,2) .

DISCUSSIONDISCUSSION

The use of three dimensional imaging during education and training may have its greatest applicability in the complex anatomy of the skull base, in particular, the temporal bone. Using this technique, we were able to provide a comprehensive visualization of the anatomy and allow for a better understanding of complex structures like the tympanic sinus and facial recess of the middle ear. The use of 3D stereoscopic images may enhance resident anatomical knowledge in otologicsurgery. These images can be obtained without great difficulty or cost in their production.

The use of three dimensional imaging during education and training may have its greatest applicability in the complex anatomy of the skull base, in particular, the temporal bone. Using this technique, we were able to provide a comprehensive visualization of the anatomy and allow for a better understanding of complex structures like the tympanic sinus and facial recess of the middle ear. The use of 3D stereoscopic images may enhance resident anatomical knowledge in otologicsurgery. These images can be obtained without great difficulty or cost in their production.

CONCLUSIONCONCLUSION

1. Ribas, GC; Bento, RF; Rodrigues Jr, AJ. Reproduções impressas de imagens tridimensionais estereoscópicas para ensino, demonstrações e documentações. Arquivos da Fundação Otorrinolaringologia 4(2): 48-54, 2000.2. Bento, RF; Ribas, GC; Sanchez, TG; Brito Neto, RV; Rodrigues Jr, AJ; Miniti, A. DemosntraçãoTridimensional da Anatomia Cirúrgica do Osso Temporal. Arquivos da Fundação Otorrinolaringologia 4(2): 43-47, 2000.

3. Ferwerda JG – The World of 3-D, 2nd ed., 3D Book Productions, Borger, 1990.

4. D’Almeida JCh – Nouvel Appareil Stéréoscopique. Comptes Rendus nº. 47, 1858, in The World of 3D, ed. Ferwerda JG, 2nd ed., 3D Book Productions, Borger, 262-264, 1990.

5. Bassett DL – A Stereoscopic Atlas of Human Anatomy, Portland, Sawyer’s Inc., 1961.

6. Chase RA – A Stereoscopic Atlas of Human Anatomy, The Bassett and Gruber Legacy, 3D Book Productions, Borger, 1994.

7. Kraus GE, Bailey GJ – Microsurgical Anatomy of the Brain: A Stereo Atlas, Williams and Wilkins, Baltimore, 1994.

8. Poletti CE, Ojemann RG – Stereo Atlas of Operative Microneurosurgery, CU Mosby Co., St. Louis, 1985.

9. Trelease RB – Toward Virtual Anatomy: A Stereoscopic 3D Interactive Mltimedia Computer Program for Cranial Osteology. Clin Anat 9:269-272, 1996.

10. Trelease RB – The Virtual Anatomy Practical: A Stereoscopic 3D Interative Multimedia Computer Examination Program. Clin Anat 11: 89-94, 1998.

1. Ribas, GC; Bento, RF; Rodrigues Jr, AJ. Reproduções impressas de imagens tridimensionais estereoscópicas para ensino, demonstrações e documentações. Arquivos da Fundação Otorrinolaringologia 4(2): 48-54, 2000.2. Bento, RF; Ribas, GC; Sanchez, TG; Brito Neto, RV; Rodrigues Jr, AJ; Miniti, A. DemosntraçãoTridimensional da Anatomia Cirúrgica do Osso Temporal. Arquivos da Fundação Otorrinolaringologia 4(2): 43-47, 2000.

3. Ferwerda JG – The World of 3-D, 2nd ed., 3D Book Productions, Borger, 1990.

4. D’Almeida JCh – Nouvel Appareil Stéréoscopique. Comptes Rendus nº. 47, 1858, in The World of 3D, ed. Ferwerda JG, 2nd ed., 3D Book Productions, Borger, 262-264, 1990.

5. Bassett DL – A Stereoscopic Atlas of Human Anatomy, Portland, Sawyer’s Inc., 1961.

6. Chase RA – A Stereoscopic Atlas of Human Anatomy, The Bassett and Gruber Legacy, 3D Book Productions, Borger, 1994.

7. Kraus GE, Bailey GJ – Microsurgical Anatomy of the Brain: A Stereo Atlas, Williams and Wilkins, Baltimore, 1994.

8. Poletti CE, Ojemann RG – Stereo Atlas of Operative Microneurosurgery, CU Mosby Co., St. Louis, 1985.

9. Trelease RB – Toward Virtual Anatomy: A Stereoscopic 3D Interactive Mltimedia Computer Program for Cranial Osteology. Clin Anat 9:269-272, 1996.

10. Trelease RB – The Virtual Anatomy Practical: A Stereoscopic 3D Interative Multimedia Computer Examination Program. Clin Anat 11: 89-94, 1998.

REFERENCESREFERENCES

5- Mastoid cortex

6- Posterior Tympanotomy

Figs 3 and 4

7- Transcanal View

7- Mastoid“antrum”

8 and 9- Semicircularcanals.

Stereoscopic 3D Images of the Anatomy of the Temporal Bone

Joao F. Nogueira Jr. MD, Diego R. Hermann MD, Ronaldo R. Américo MD,Iulo S. Barauna Fo. MD, Fernando O. Balieiro MD, Raquel G. Stamm,

Richard Jonh Harvey MD, Aldo C. Stamm MD, PhD.Sao Paulo ENT Center

Professor Edmundo Vasconcelos Hospital Sao Paulo – Brazil

Stereoscopic 3D Images of the Anatomy of the Stereoscopic 3D Images of the Anatomy of the Temporal Bone Temporal Bone

JoaoJoao F. Nogueira Jr. MD, Diego R.F. Nogueira Jr. MD, Diego R. HermannHermann MD, Ronaldo R. AmMD, Ronaldo R. Améérico MD,rico MD,Iulo S. Barauna Iulo S. Barauna FFoo. MD, Fernando O. . MD, Fernando O. BalieiroBalieiro MD, Raquel G.MD, Raquel G. StammStamm, ,

Richard Richard JonhJonh HarveyHarvey MD, Aldo C. MD, Aldo C. StammStamm MD, MD, PhDPhD..Sao Paulo ENT Center

Professor Edmundo Vasconcelos Hospital Sao Paulo – Brazil

joaoflavioce@hotmail.comwww.centrodeorl.com.br

Joao Flavio Nogueira Jr.R Borges Lagoa, 145T0, 3º. Andar.CEP: 04038-905, São Paulo, Brazil