Radio-Morphometric Evaluation of Greater Palatine Canal and Pterygopalatine Fossa Component: Maxillary Anesthetic Implications.

This is a retrospective analytical cross-sectional study involving 131 cone-beam computed tomography (CBCT) scans of adult (18-99 years) that assessed greater palatine canal (GPC) attributes (length, curvature angle, diameter of curvature) and the type of the trajectory of GPC-pterygopalatine fossa (PPF) component. The GPC is an important landmark that connects the oral cavity and PPF. It contains greater and lesser palatine nerves, along-with descending palatine artery and vein by extending from the inferior part of the PPF to the hard palate. The GPC acts as a pathway for infiltration of local anesthesia. The inferior orbital fissure (IOF) is in close proximity to these vital anatomic structures and hence accurate identification of its location during regional block anesthesia is crucial. This is one of the very few studies investigating these important structures on CBCT scans highlighting the importance of preoperative scans for the anatomic determination. The images were analyzed for the lengths and anatomic paths of the right and left GPC-PPF in sagittal plane. The diameters of the upper (higher bony aspect of PPF) and lower openings (GPC opening) displayed statistically significant differences in the comparison between males and females (P < 0.05). Overestimation or underestimation of the GPC length can cause a lack of anesthesia and undesirable diffusion of the anesthetic solution into the orbit thorough the IOF causing diplopia, or into the cranial cavity. A thorough understanding of GPC length and pathway types is obligatory for proper anesthetic administration and performing any maxillofacial procedures.

Dark circles: etiology and management options.

Given their multifactorial nature and the fact that individual patients may have more than a single underlying cause, cosmetic practitioners should be well versed in a number of potential treatment options encompassing all facets of under-eye dark circles. New therapeutic options are also forthcoming. Longer-lasting HA fillers, wavelength tunable laser devices, and topicals speeding up healing and enhancing results after fractionated laser therapy will all serve to make the future of dark circle treatment unabatedly bright.

A morphological and biometric study of the infraorbital foramen (E2 - sibai point) in adult skulls / Estudio morfológico y biométrico del foramen infraorbital (Punto E2 - sibai) en cráneos de adultos

The objective of this work was to study the morphology and biometry of the infraorbital foramen (FIO), variations in its shape, size and number as well as to obtain measurements of its location. 60 dry skulls were analyzed. The test of Qui-quadrant and the T Test were used in measurements with a 5 percent significance. On the right side, the FIO was measured at a distance of 6.49(+/-1.68) mm from the lower, 39.65(±3) mm from the upper, 17.7(+/-2.97) mm from the medial and 20.46(+/-2.9) mm from the lateral margin of the orbit; its pear-shaped opening distance was 13.67(+/-2.17) mm. On the left side, the distance of the FIO to the lower margin of the orbit was 6.52(+/-1.82) mm; to the upper margin was 39.9(+/-2.62) mm and to the lateral and medial margin were 17.93(+/-2.58) mm and 21.12(+/-3) mm, respectively; its distance to the pear-shaped opening was 14.26(+/-1.83) mm. It was found predominately in an oval shape, in 39 (65 percent) of the skulls, on both sides. Accessory foramens were present in 11 samples on the right and in 15 samples on the left side. The FIO was most frequently found on the side of, or laterally to the sagittal plane that passes through the middle of the supraorbital foramen/ incisures, in 38 skulls (63.3 percent) on the right side and in 45 skulls (75 percent) on the left and middle to the zigomatic-maxillary suture, in 41 skulls (68.3 percent) on right and in 42 skulls (70 percent) on the left side, besides being most frequently found in a region between the first and second premolars, in 22 skulls (36.7 percent) on the right side and in 17 skulls (28.3 percent) on the left...

El objetivo de este trabajo fue estudiar la morfología y biometría del foramen infraorbitario (FIO), las variaciones en su forma, tamaño y número y además, determinó su ubicación.Se utilizaron 60 cráneos aplicándose las prueba de Chi-cuadrado y t student con una significancia del 5 por ciento.En el lado derecho, la distancia del FIO al margen inferior de la órbita fue de 6,49 (+/- 1,68) mm, 39,65 mm (+/- 3) al margen superior mm, 17,7 mm (+/- 2,97) al margen medial y 20,46 (+/- 2,9) y al margen lateral de la órbita, respectivamente. La distancia de apertura fue 13,67 (+/- 2,17) mm.En el lado izquierdo, la distancia del FIO al margen inferior de la órbita fue 6,52 (+/- 1,82) mm; al margen superior fue 39,9 (+/- 2,62) mm y a los márgenes lateral y medial fue 17,93 (+/- 2,58) mmy 21,12 (+/- 3) mm, respectivamente. La distancia a la abertura piriforme fue 14,26 (+/- 1,83) mm. Su forma era predominantemente ovalada, en 39 (65 por ciento) de los cráneos. Forámenes accesorios estaban presentes en 11 muestras en el lado derechoy en 15 muestras en el lado izquierdo.El FIO estaba localizado más frecuentemente lateral al plano sagital que pasa por el centro del foramen supraorbital. De estos casos, en 38 cráneos (63,3 por ciento) en el lado derecho y en 45 cráneos (75 por ciento) en el lado izquierdo.Los FIO estaban en el punto medio de la sutura cigomática-maxilar en 41 cráneos (68,3 por ciento) en el lado derecho y en 42 cráneos (70 por ciento) en el lado izquierdo. Los FIO estaban más frecuentemente localizados en relación al primer y segundo premolares, en 22 cráneos (36,7 por ciento) en el lado derecho y en 17 cráneos (28,3 por ciento) en el lado izquierdo...

Nonclassical innervation patterns in mammalian extraocular muscles.

PURPOSE: The abducens (CN6) and oculomotor (CN3) nerves (nn) enter target extraocular muscles (EOMs) via their global surfaces; the trochlear (CN4) nerve enters the superior oblique (SO) muscle on its orbital surface. Motor nn are classically described as entering the EOMs in their middle thirds. We investigated EOM innervation that does not follow the classic pattern. METHODS: Intact, whole orbits of two humans and one each monkey, cow, and rabbit were paraffin embedded, serially sectioned in coronal plane, and prepared with Masson's trichrome and by choline acetyltransferase (ChAT) immunohistochemistry. Nerves innervating EOMs were traced from the orbital apex toward the scleral insertion, and some were reconstructed in three dimensions. RESULTS: Classical motor nn positive for ChAT entered rectus and SO EOMs and coursed anteriorly, without usually exhibiting recurrent branches. In every orbit, nonclassical (NC) nn entered each EOM well posterior to classical motor nn. These NC nn entered and arborized in the posterior EOMs, mainly within the orbital layer (OL), but often traveled into the global layer or entered an adjacent EOM. Other NC nn originated in the orbital apex and entered each EOM through its orbital surface, ultimately anastomosing with classical motor nn. Mixed sensory and motor nn interconnected EOM spindles. CONCLUSIONS: EOMs exhibit a previously undescribed pattern of NC innervation originating in the proximal orbit that partially joins branches of the classical motor nn. This NC innervation appears preferential for the OL, and may have mixed supplemental motor and/or proprioceptive functions, perhaps depending upon species. The origin of the NC innervation is currently unknown.

Extension of the one-piece orbitozygomatic frontotemporal approach to the glenoid fossa: cadaveric study.

OBJECTIVE: Resection of the glenoid fossa has been described as part of cranial approaches to the clivus and subtemporal approaches. However, radical resection carries a significant risk of postoperative temporomandibular joint dysfunction. We examine a simple variation of our previously described one-piece frontotemporal orbitozygomatic (FTOZ) osteotomy that adds en bloc resection of the root of the zygomatic arch and a portion of the glenoid fossa. METHODS: Five cadaveric fixed heads injected with colored silicone underwent an FTOZ osteotomy that extended to the root of the zygomatic arch and glenoid fossa. RESULTS: A step-by-step guide to the surgical technique is described, with illustrations to depict the glenoid fossa keyhole and bony cuts that free the zygomatic arch and portions of glenoid fossa. The first cut was made through the posterior root, and the second cut was made through the anterior root of the zygomatic arch. CONCLUSION: In this cadaveric study, extension of the one-piece FTOZ approach included the posterior root of the zygoma and the lateral part of the glenoid fossa. En bloc resection of the glenoid fossa and root of the zygomatic arch, together with the FTOZ osteotomy, facilitated reconstruction of the temporomandibular joint and increased the amount of exposure obtained with this FTOZ osteotomy. Comprehensive understanding of functional outcomes awaits further clinical study.

[Anatomical study on Jingming (BL 1)].

OBJECTIVE: To explore the anatomical structures, and depth and direction of needling at Jingming (BL 1), so as to provide anatomical basis for its clinical application. METHODS: Forty-eight adult orbital specimens were observed by dissection. RESULTS: When a needle was vertically inserted into Jingming (BL 1), the needle tip will past through the skin, subcutaneous tissue, medial palpebral ligament, medialis rectus and orbital adipose body. Above the body of the needle, there are ophthalmic artery, anterior ethmoidal artery and nasociliary nerve. The average distance between the skin at the punctured point and the anterior ethmoidal artery is (18.25 +/- 4.45) mm, with an angle of (12.5 +/- 5.5) degrees, and the average distance between the skin at the punctured point and the optic nerve tunnel frontal point is (43.37 +/- 7.84) mm. CONCLUSION: To avoid bleeding caused by injuring the anterior ethmoidal artery, acupuncture at Jingming (BL 1) should avoid deeply inserting needled back-upwards and upwards, and the needling depth should not exceed 30.36 mm to avoid injury of the optic nerve tunnel frontal point.

[Locoregional anesthesia in ophthalmology: update]. / Anestesia locorregional en oftalmología: una puesta al día.

Regional anesthesia for ophthalmic procedures has changed significantly in the past ten years. Phacoemulsification for cataract surgery through corneal microincisions, soft foldable lenses and topical anesthesia simplify surgery such that most operations can be performed on an outpatient basis. Some anesthetic blocks are performed by either anesthesiologists or ophthalmologists, who should understand the advantages and disadvantages for each patient. This review discusses anatomical aspects of interest to the anesthesiologist, the main techniques used and anesthetic innovations, complications and certain controversies such as management of the patient who is taking medications that alter hemostasis, the withdrawal of hyaluronidase in some countries and the systematic ordering of tests before the procedure.

Guidance of retrobulbar injection with real-time tomographic reflection.

OBJECTIVE: Retrobulbar and peribulbar injections are common ophthalmologic procedures used to deliver anesthetics and other medications for ophthalmic therapy and surgery. These injections, typically performed without any type of guidance, can lead to complications that are rare but visually devastating. The needle may penetrate the optic nerve, perforate the globe, or disperse toxic quantities of drugs intraocularly, causing major visual loss. Sonographic guidance may increase the accuracy of the needle placement, thereby decreasing the incidence of complications. However, difficulties arise in coordinating the relative location of the image, the needle, and the patient. Real-time tomographic reflection is a new method for in situ visualization of sonographic images, permitting direct hand-eye coordination to guide invasive instruments beneath the surface of the skin. METHOD: In this preliminary study, real-time tomographic reflection was used to visualize the eye and surrounding anatomic structures in a cadaver during a simulated retrobulbar injection. RESULT: The needle tip was easily followed as it was advanced into the retrobulbar space. CONCLUSIONS: The images presented in this preliminary study show the use of real-time tomographic reflection to visualize insertion of an invasive instrument into the human body.

Anesthesia for intraocular surgery.

Surgeons must decide on the type of anesthesia to use when performing cataract surgery. These "viewpoints" articles provide a well-balanced discussion offering the pros and cons of both topical anesthesia and retrobulbar/peribulbar injection. Dr. Dutton gives an overview of both techniques, focusing on relevant orbital anatomy. Drs. Hassan, Edelhauser and Kim, review the various types of topical anesthesia currently in use, and Drs. Spriggs and Broocker examine retrobulbar and peribulbar injections. Both techniques are associated with advantages and risks, so each surgeon must decide which technique is best suited for his or her own practice.

Orbital depth measurements of human skulls in relation to retrobulbar anesthesia.

To investigate the orbital depth in human skulls in relation to retrobulbar anesthesia, we measured the distance between the lateral margin of the optic foramen and the border of the medium and outer third of the inferior orbital rim (retrobulbar needle pathway) in 50 skulls (25 males and 25 females). This distance varied from 4.4 to 5.7 cm in males (mean 5.024, SD 0.272) and from 4.5 to 5.5 cm in females (mean 4.9, SD 0.204). There was no real difference between males and females (p>0.05). For the total of 50 skulls the mean distance was 4.962 cm (SD 0.246). Shallow and deep orbits exist in both males and females but individuals with shallow orbits are obviously more susceptible to optic nerve injury by the retrobulbar needle.

Relaçöes anatômicas do ponto de acupuntura E-2 (Sibai) localizado no forame infra-orbital / Anatomic relations of the acupuncture point E-2 (Sibai) located in the infraorbital foramen

O ponto E-2 (Sibai) é utilizado no tratamento de paralisia facial, neuralgia do trigêmeo, afecçöes oculares e sinusite maxilar. O presente estudo visa determinar a orientaçäo do ponto E-2 (Sibai), relacionando-o com referências ósseas anatômicas do crânio e o seu eixo e a profundidade de inserçäo. Material - 100 crânios de esqueleto humano masculino e feminino, acima de 15 anos de idade. Método - Foram medidas as distâncias do forame infra-orbital à margem orbital inferior, ao alvéolo dentário do segundo pré-molar superior, à linha mediana anterior. Foi determinado o eixo do forame nos planos frontal, sagital e transversal e sua profundidade. Resultados - O teste t de Student näo mostrou diferença significante entre os valores do lado direito e esquerdo e em relaçäo ao sexo masculino e feminino. A distância média do forame intra-orbital à margem orbital inferior foi de 0,68cm; ao alvéolo dentário do segundo pré-molar superior foi de 3,01cm; à linha mediana anterior foi de 2,71 cm. A profundidade média foi de 1,56 cm. Os ângulos, em graus, formados com os planos frontal, sagital e transversal foram de, respectivamente, 60,4, 28,5 e 123,7. Conclusäo - O ponto E-2 (Sibai) localiza-se no crânio do esqueleto humano adulto 0,68 cm abaixo da margem orbital inferior, 3,01 cm acima do alvéolo dentário do segundo pré-molar superior e 2,71 cm lateralmente à linha mediana anterior, a uma profundidade de 1,56 cm, e seu eixo forma um angulo de 60,4 graus com o plano frontal, 28,5 graus com o plano sagital e 123,7 graus com o plano transversal.

Hydroxyapatite paste (BoneSource) used as an onlay implant for supraorbital and malar augmentation.

This study was designed to evaluate hydroxyapatite paste (BoneSource; Leibinger Corp., Dallas, TX) as an alloplastic implant for supraorbital and malar augmentation. Ten male Sprague-Dawley rats had cylindrical onlay implants made of the hydroxyapatite cement placed above their left orbits on the supraorbital rim. Size-matched Medpor implants were placed similarly on the right side. To test the utility of this new material in the midface, hydroxyapatite paste and Medpor implants were also placed in the right malar regions of a different set of rats. The implants were left in situ for 6 months and examined for evidence of bone ingrowth, infection, migration, resorption, and detrimental effects on the surrounding tissue. All hydroxyapatite cement implants provided excellent soft tissue projection and demonstrated steadfast adherence to the adjacent bone. The surface of the hydroxyapatite implant in contact with the native bone demonstrated evidence of native bony ingrowth into approximately 12% of the implant. There was no evidence of implant migration or gross infection. There was no bony resorption below the hydroxyapatite paste, but four of the Medpor implants showed evidence of this in the underlying bone. Only one negative aspect to the use of hydroxyapatite cement paste as an onlay implant was identified. Two of the supraorbital and one of the malar hydroxyapatite implants had approximately 20 to 25% volume loss during the experimental period (P = 0.05). Overall, the vast majority of the implants retained their original form. We concluded that hydroxyapatite paste may possibly be used to effectively augment bone in the supraorbital and malar regions. Its biocompatibility, excellent bony adherence, and tendency to be replaced by natural bone may make it suitable for the aesthetic patient. The possible resorptive aspects of the material need to be evaluated further.

Single quadrant sub-Tenon's block. Evaluation of a new local anaesthetic technique for eye surgery.

The sub-Tenon's technique uses blunt dissection and a blunt probe to inject local anaesthetic into the posterior sub-Tenon's space. This avoids the potentially catastrophic complications which result from passing a sharp needle blindly into the orbit and retrobulbar space. The anatomy of Tenon's capsule and the block technique is described. Results of the block quality and degree of patient comfort from 300 consecutive sub-Tenon's blocks are also described. No significant complications occurred in this series. Single-quadrant sub-Tenon's block offers an excellent quality of anaesthesia, is virtually painless to perform and avoids complications due to passage of a sharp needle into the orbit.

Computer-aided geometric modeling of the human eye and orbit.

The author advocates, as a long-term development agenda for the profession, a shift in the working methods of medical illustrators from a two-dimensional image processing mode to a computer-aided design and drafting (CADD) mode. Existing CADD technology, which can make short work of the complex graphic construction problems of anatomical visualization, performs virtually all of its manipulations through systematic exercise of graphic geometry which illustrators tend to reduce to an intuitive, almost vestigial supplement to 2D image processing methods. The primary barrier to the immediate use of CADD is a lack of geometric database materials on anatomical component systems of the body. An on-going experimental project in modeling the human eye and orbit, utilizing a Silicon Graphics Iris workstation and Control Data Corporation's Integrated Computerized Engineering and Manufacturing (ICEM) software, exemplifies the preparatory work needed to create such database materials.

An anatomic study of retrobulbar needle path length.

One hundred twenty human orbits were measured to determine orbital depth and the position of orbital structures in relation to the length of needles used for retrobulbar anesthesia. The distance from the inferior temporal orbital rim to the nasal entrance of the optic foramen ranged from 42 to 54 mm. Taking into account the size of the optic nerve, the common 38-mm (1.5-in) retrobulbar needle could perforate the optic nerve where it is fixed in front of the foramen in over 11% of the population. The authors recommend that needles be placed less than 31 mm (1.25 in) behind the orbital rim for both retro- and peribulbar anesthesia.

The anatomy and histology of the anophthalmic socket--is the myofibroblast present?

For some anophthalmic patients, the contracted socket is a severe problem that precludes the wearing of a prosthesis. A normal and cosmetically acceptable appearance is dependent on the ability of a socket to retain a prosthesis. The disfigurement and distress caused by the contracted socket and its inability to accommodate a prosthesis may have a profound detrimental effect on the patient's career, self-esteem, and psychosocial interactions. The tissue dynamics at work in the anophthalmic socket and in the contracting socket are not yet understood. There are many unanswered questions regarding the histology and anatomy of the normal, as well as the contracting, socket. The tissue responsible for clinical contraction has not been identified. This thesis, using the cynomolgus monkey socket as an experimental model, investigated healing in both the normal and contracting socket. Qualitative observations of the anatomy and histology of eight sockets were made. Two of the sockets were treated with Croton oil to induce contractions. Biopsy specimens from two human sockets, one contracted and the other merely volume deficient, were also examined. Histopathology of the normal and contracting sockets were compared. Myosin subfragment 1 staining of actin for electron microscopy and immunoperoxidase staining of actin for light microscopy were performed on selected specimens. The myofibroblast, probably a modified fibroblast, is known to be present in the early stages of open wound healing and in contracting scar tissue elsewhere in the body. The myofibroblast has been incriminated as an agent generating contractile force. Under the conditions of this experiment, cells with the characteristics of myofibroblasts were identified by both immunoperoxidase staining and electron microscopy. They were found in healing noncontracting and contracting sockets. Cytoplasmic actin was also distinguished in arterioles, venules, capillaries, myoepithelial cells, smooth muscle, and skeletal muscle.

A comparison of porous composite PTFE/graphite and PTFE/aluminum oxide facial implants in primates.

Comparison of tissue ingrowth density values for Proplast I and its aluminum oxide analog, Proplast II, when implanted on the primate infraorbital rim and inferior border of the mandible, showed no difference between the two test materials. A similar comparison of local cellular response ratings showed slightly less response to Proplast II. Microscopic and clinical examination did not otherwise reveal any significant differences in biologic reaction to these materials.

The CT-topography of retrobulbar anesthesia. Anatomic-clinical correlation of complications and suggestion of a modified technique.

The anatomic relationship of an injection needle as traditionally placed in retrobulbar anesthesia to optic nerve, orbital vessels and eye muscles is demonstrated by computed tomography. The clinical complications of retrobulbar injections are reviewed and correlated to the orbital topography in different positions of gaze, as analyzed in anatomic sections and CT images. The results indicate that with the transitional technique of retrobulbar injection the most important orbital structures are in the immediate neighbourhood of the needle. A different injection technique is discussed.