Search

Copyright of Oral & Maxillofacial Surgery is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To evaluate the uveal and capsular biocompatibility of 3 types of sharp-edged foldable intraocular lenses (IOLs) in eyes with pseudoexfoliation syndrome (PEX)., Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria., Methods: Eighty-five eyes with PEX had implantation of 1 of the following sharp-edged 3-piece IOLs: hydrophilic acrylic (Injectacryl F3000, OphthalMed), hydrophobic acrylic (AcrySof MA60MB, Alcon), or silicone (CeeOn 911, AMO). Postoperative evaluation (flare, cellular reaction, and capsular reaction) was performed at 1, 3, and 7 days as well as 1, 3, 6, and 12 to 18 months., Results: One year after surgery, flare was comparable between the IOLs. In terms of uveal biocompatibility, whereas the Injectacryl had the highest deposition of debris on the IOL surface (P = .04), the CeeOn 911 had significantly more small round cells in the first 6 months (P<.03). The AcrySof had the highest number of foreign-body giant cells (P = .01). In terms of capsular biocompatibility, lens epithelial cell outgrowth was highest in the AcrySof group (P<.02). Anterior capsule opacification was comparable between the 3 groups. Posterior capsule opacification was mild in all groups but was significantly greater in the Injectacryl group (P<.05). There were no cases of clinically significant IOL decentration or capsule contraction., Conclusions: In general, inflammatory cells accumulated more easily on hydrophobic IOLs than on hydrophilic IOLs; the AcrySof IOL had the highest prevalence of foreign-body giant cells. All 3 IOLs had good biocompatibility, although the AcrySof group had increased inflammatory signs.

Unlabelled: Receptors for somatostatin (SST) (SSTR) are expressed on various tumor cells as well as on activated lymphocytes. Previous data have shown that (99m)Tc-P829 binds with high affinity to many different types of tumor cells as well as to leukocytes via the human hSSTR2, hSSTR3, and hSSTR5 target receptors. Consequently, (99m)Tc-P829 was successfully introduced as a peptide tracer for tumor imaging. In this study, we evaluated the orbital uptake of (99m)Tc-P829 in patients with active and inactive thyroid-associated orbitopathy (TAO), accompanied by lymphocyte infiltration in the acute stage and by muscle fibrosis in the chronic stage of the disease., Methods: To evaluate its clinical usefulness in Graves' disease, (99m)Tc-P829 scintigraphy (approximately equal to 740 MBq) was performed in 44 patients with TAO (median duration, 19 mo; range, 1-360 mo). The clinical activity of the orbital disease was graded by the NOSPECS (no signs or symptoms; only signs, no symptoms; signs only; proptosis; eye muscle involvement; corneal involvement; sight visual acuity reduction) classification of the American Thyroid Association, the clinical activity score (CAS), and the superonasal index (SNI). SPECT (360 degrees ) and planar studies were completed within 3 h after injection. Orbital (O) regions of interest (ROIs) were compared with temporoparietal and occipital (OCC) ROIs. Orbital uptake ratios in Graves' disease were compared with data obtained from lung cancer patients with no eye disease (n = 22)., Results: Overall, (99m)Tc-P829 biokinetics were the same in Graves' disease patients as in lung cancer patients, showing a rapid blood clearance and visualization of the facial bones within minutes of injection. In all control patients, the orbit appeared as a "cold area," whereas visual orbital accumulation of (99m)Tc-P829 was found in patients with active TAO (O/OCC ratios: 1.26 +/- 0.04 vs. 1.69 +/- 0.04; P < 0.01, respectively). Patients with active eye disease (n = 25) presented with an increased orbital uptake of (99m)Tc-P829 compared with patients with inactive disease (n = 19; O/OCC ratio: 1.12 +/- 0.05; P < 0.01). A statistically significant correlation was found between CAS and the orbital uptake (O/OCC ratio) values (r = 0.90), whereas no correlation could be documented regarding the NOSPECS classification as well as the SNI., Conclusion: In TAO, (99m)Tc-P829 yields high orbital binding with good clinical correlation. The better image quality due to the high energy of technetium, the lower radiation dose for patients and personnel, and the short acquisition protocol favor SSTR scintigraphy with (99m)Tc-P829 over (111)In-labeled compounds. The in-house availability of the radiotracer and cost-effectiveness are further advantages.

Purpose: In this retrospective study, we evaluated isolated blowout fractures of the orbital floor by region-of-interest measurements from coronal computed tomography (CT) scans and their relationship to ophthalmologic findings., Patients and Methods: Fracture area and volume of displaced tissue of blowout fractures in 38 patients were measured from coronal CT scans. Measurement was performed by identifying distances (for area calculation) of the fracture and identifying areas (for volume calculation) of the displaced tissue in each CT slice. The calculated data were then compared with the amount of enophthalmos, presence of diplopia, and limitation of ocular motility., Results: Orbital floor area (mean +/- SD) was 5.72 +/- 1.07 cm(2); fracture area, 2.63 +/- 1.20 cm(2); and the volume of displaced tissue, 1.15 +/- 0.91 mL. The average proportion of the fracture within the orbital floor was 45.3 +/- 17.6%. Fracture area and volume of displaced tissue were significantly positively correlated with enophthalmos and diplopia and not correlated with the limitation of ocular motility. For enophthalmos of 2 mm or greater, mean fracture area (mean +/- SD) was 4.08 +/- 1.09 cm(2) and volume of displaced tissue was 1.89 +/- 1.19 mL; for less than 2-mm enophthalmos, 1.98 +/- 0.83 cm(2) and 0.83 +/- 0.58 mL, respectively. Enophthalmos of 2 mm can be expected with 3.38 cm(2) of fracture area and 1.62 mL of displaced tissue., Conclusions: Region-of-interest measurement from coronal CT scan has an application in the assessment of patients with pure blowout fractures of the orbital floor and adds useful information in posttraumatic evaluation of orbital fractures., (Copyright 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:1267-1272, 2002)

Numerous reports have described the use of the temporalis muscle as a pedicled flap in reconstructive surgery. A detailed knowledge of the supplying vessels and nerves is necessary for functionally successful muscle transposition. However, controversial anatomic descriptions exist. In this study, 60 human cadavers were investigated to identify the arteries and nerves supplying the temporalis. Forty-three cadavers were dissected after embalming with 10% phenol/formaldehyde. An additional 10 cadavers were examined after injecting latex/barium sulfate (ratio, 1:1) to show the parts of the temporalis supplied by each artery using radiography. The innervating motor branches of the trigeminal nerve were identified by the Karnovsky technique in seven fresh cadavers. In all specimens, three arteries supplying the temporalis were identified: the anterior deep temporal artery (anterior part, 30 percent muscle mass), the posterior deep temporal artery (central part, 51 percent muscle mass), and the medial temporal artery (occipital and in 25 percent upper part, 19 percent muscle mass). Motor branches of the trigeminal nerve innervated the temporalis: the deep temporal nerves of the mandibular nerve (98 percent, central part), branches of the buccal nerve (95 percent, anterior part), and branches of the masseteric nerve (69 percent, posterior part). A remarkable variation of innervating nerve branches, and in 12 percent peripheral anastomoses between the motor nerve branches, were observed. The various numbers of innervating nerve branches demonstrate the difficulty of creating innervated or selectively denervated pedicled muscle flaps for reinnervation. Nevertheless, at least two different pedicled flaps using the anterior or central part of the temporalis can be selectively used for reconstructive surgery.

Numerous reports have discussed the use of the external oblique abdominal muscle as a pedicled or a free flap for defect coverage. A detailed description of the supplying vessels and nerves is a prerequisite for successful tissue transfer but so far is not available in the literature. A study of the arteries and nerves supplying the external oblique abdominal muscle was carried out in 42 cadavers after injection of a mixture of latex and bariumsulfate. In seven fresh cadavers the motor branches were identified with the Karnovsky technique. Three different groups of arteries were identified as the nurturing vessels. The cranial part of the muscle is supplied by two branches of the intercostal arteries. While the lateral branches run on the outer surface of the muscle together with the nerves, the anterior branches enter the muscle from its inner surface. The caudal part of the muscle derives its main blood supply from one or two branches of the deep circumflex iliac artery (94.7%) or the iliolumbar artery (5.3%). The external oblique abdominal muscle is innervated by motor branches of the lateral cutaneous branches of the anterior spinal nerves in a segmental pattern. With the exception of the subcostal nerve the motor branches enter the outer surface of the muscle digitation arising from the rib above. The results show that the cranial half of the external oblique abdominal muscle has a strictly segmental blood and nerve supply while the caudal half of the muscle derives its main blood supply from one artery but still shows a segmental innervation., (Copyright 1999 Wiley-Liss, Inc.)

The technique of laser tissue welding with a low-output CO2 laser has become popular due to the minimal amount of nerve tissue damage caused. The purpose of this study was to ascertain the efficacy of nerve coaptation by laser tissue welding in comparison to micro-sutures. In a first series of 15 rats, peripheral nerves were transsected. 24 nerves were coaptated by laser welding (LW) with different parameters in order to evaluate the optimal laser settings. For comparison, six nerves were coapted (NS) with four 10/0 nylon sutures. Finally, the nerves were removed and the tensile strength of the different coaptations determined. The best results of the laser welds were obtained at laser settings of 40 to 60 mW in the continuous mode resulting in a tensile strength of 9.5 +/- 2.2 g. The tensile strength was 39.3 +/- 7.3 g for the sutured coaptation. In a second series, one sciatic nerve was coapted in thirteen rats by laser welding (LW) (60 mW, cont. mode) and in eleven rats using four 10/0 nylon sutures (NS). After six months, the Sciatic Function Index (SFI) was evaluated and the nerves were harvested for histological examination of transverse and longitudinal sections. All animals showed good regeneration and none of the 24 nerve coaptations showed dehiscence. The SFI was for the NS-group -94 +/- 23 and for the LW-group -77 +/- 20. The mean number of myelinated nerve fibres (NS 10,170 +/- 2512 vs. LW 11,902 +/- 1649) and the fibre diameter (NS 4.30 +/- 0.14 um vs. LW 4.02 +/- 0.59 microns) of the nerves distal to the coaptation were similar in both groups and showed no statistical difference. We conclude that nerve coaptation by CO2-laser welds are as successful as the 10/0 nylon sutures in the animal model. Improvements of welding techniques may in the future reduce nerve damage even further and so yield even better functional results.

Background: Extrafusal muscle fibers of human striated skeletal muscles are known to have a uniform innervation pattern. Motor endplates (MEP) of the "en plaque" type are located near the center of muscle fibers and distributed within the muscles in a narrow band. The aim of this study was to evaluate the innervation pattern of human facial muscles and compare it with that of skeletal muscles., Methods: Ten facial muscles from 11 human cadavers were dissected, the nerve entrance points located, and the dimensions measured. All muscles were stained in toto for MEPs using Acetylcholinesterase (AChE) and examined under the microscope to determine their location. Single muscle fibers were teased to evaluate the stained MEPs., Results: The length of the different facial muscles varied from 29 to 65 mm, which correlated to the length of the corresponding muscle fibers. MEP zones were found on the muscles in the immediate vicinity of the nerves' entrance points and located eccentrically. Numbers and locations varied from muscle to muscle. Three MEP zone distribution patterns were differentiated: numerous small MEP zones were evenly spread over the muscle, a predominant MEP zone and two to three small zones were spread at random, and two to four MEP zones of equal size were randomly scattered. One MEP of the "en plaque" type was found in 73.8% of the muscle fibers and two to five MEPs were found in 26.2%. The distances between the multiple MEPs on one muscle fiber varied from 10 to 500 microm., Conclusions: This study suggests that facial muscles differ from skeletal muscles regarding distribution and number of MEPs. The eccentric location of MEP zones and multiple MEPs suggests there is an independent mechanism of neural regulation in the facial muscle system.

To date, the external oblique muscle has been considered to have a purely segmental vascular supply and therefore has been used surgically only as a pedicled flap. To better define the vascular anatomy and nerve supply of the muscle, we performed arterial injection studies and dissected the nerves that entered the muscle in 35 human cadavers. We found that in addition to the segmental arteries, one or two large branches of the deep circumflex iliac artery contributed significantly to the blood supply of the external oblique muscle in 33 of the 35 cadavers. We also found that the lateral cutaneous branches of the intercostal nerves entered and supplied the muscle near its origin from the rib in a strictly segmental pattern. These anatomic findings enabled us to transplant the external oblique muscle successfully as a free flap based on the deep circumflex iliac vessels in six patients. The muscle flap is thin, pliable, and can be combined with an iliac bone or an abdominal skin transplant. Its vascular pedicle is long (mean 12 cm) and of adequate diameter for microvascular repair. The donor scar of the flap is inconspicuously situated along the inguinal ligament and the iliac crest. Finally, since the muscle has a multiple nerve supply, it has the potential to provide several functional units at the recipient site when transplanted as a functional free flap.

Background and Objective: The purpose of this study was to determine whether the milliwatt laser can suppress neuroma formation at the end of a divided nerve., Study Design/materials and Methods: The peripheral nerves of eight rats were transected with microscissors and the cross-sectional area of their proximal ends was irradiated using the CO2 milliwatt laser. The power ranges used were similar to those applied to weld neural tissue., Results: None of the eight irradiated nerve ends formed a neuromatous bulb and only one of them regenerated into the surrounding tissues. Histologically, these nerve ends did not show the disorganized picture of classic neuromas. On morphometric measurements, they contained less connective tissue than the control nerve ends (P < 0.001) and their nerve fibers were larger in diameter (P < 0.001) and better myelinated (P < 0.001)., Conclusion: These findings in rats show that the CO2 milliwatt laser has the ability to suppress neuroma formation at the end of a divided nerve.

In 17 patients acetylcholinesterase activity was used to differentiate between sensory and motor fascicles in median and ulnar nerve repair of the hand. Eleven patients received follow-up evaluation 1 to 11 years after surgery, and at that time clinical and electroneurographic examinations were performed to evaluate the techniques. Clinical examination showed that four patients had regained on average 71.9% of hand function after median nerve repair, one patient had regained 83.6% of hand function after ulnar nerve repair, four patients had regained on average 53.3% of hand function after median and ulnar nerve repair, and two patients had regained on average 43.5% of hand function after median and partial ulnar nerve repair. The contribution of the ulnar nerve to reinnervation of the thenar muscles was 68.5%, whereas the median nerve did not contribute to reinnervation of the hypothenar muscles. Distal latencies for the median nerve showed a delay of 36% of the upper limit of normal value, and those for the ulnar nerve revealed a delay of 21.5%. This study demonstrated that sensory/motor-differentiated nerve repair of the median and ulnar nerves is possible and can be proven electroneurographically.

To investigate the value of motor sensory differentiated nerve repair, we examined a group of 9 patients with motor sensory differentiated nerve repair and a group of 13 patients without motor sensory differentiated nerve repair. The clinical and electroneurographic findings were compared. For the clinical examination, Millesi's scoring system was used. The hand function after motor sensory differentiated median nerve repair was 72% +/- 16% compared with 57% +/- 14% without motor sensory differentiation. The hand function after motor sensory differentiated median and ulnar nerve repair was 53% +/- 12% compared with 43% +/- 24% without motor sensory differentiation. After ulnar nerve repair the achieved values for hand function were high even without motor sensory differentiation. Our results indicate that intraoperative motor sensory differentiation of injured nerves is helpful to reestablish particularly the sensory function in median nerve injuries.

Since 1979 acetylcholinesterase has been used in clinical practice for motor sensory differentiation. It was first used for median and ulnar nerve injuries at the wrist. Recently the application was extended to secondary nerve repair, including plexus reconstruction. The aim of this study was to present, for the first time, clinical results of motor sensory differentiated median and ulnar nerve repair and to show the advantage of this method in secondary repair. We compared a group of nine patients with motor sensory differentiated median and ulnar nerve repair with a group of 13 patients without motor sensory differentiation. Sensibility testing, strength measurements, and anatomical examinations were performed. The hand function was expressed in percentage values. Compound muscle action potentials and sensory antidromic conduction velocities were measured electroneurographically. Sensibility recovery was significantly better after motor sensory differentiated median nerve repair (P < 0.05). In secondary nerve repair acetylcholinesterase was used additionally for evaluating the level of resection of the proximal stump. The time required for perioperative histochemical differentiation has now been reduced to 2 hr.

Fourteen functionally relevant mimic muscles of nine human bodies were analyzed with respect to their muscle fiber sizes and their histochemical fiber type composition. In cryostat sections stained for actomyosin ATPase, type 1 and type 2 fibers were evaluated separately by means of computer-assisted image analysis. The fiber diameters varied between 20.24 and 41.45 microns. According to the proportions of the fiber types, the mimic muscles could be classified into three groups: (1) phasic muscles, with 14 to 15 percent type 1 fibers, (2) intermediate muscles, with 28 to 37 percent type 1 fibers, and (3) tonic muscles, containing 41 to 67 percent type 1 fibers. It is concluded that one has to consider this diversity of mimic muscles when planning the surgical reconstruction of facial paralysis.