A Pilot Study to Evaluate the Usefulness of Optical Coherence Tomography for Staging Iris Pigmented Lesions in Cats.

This study investigated the utility of optical coherence tomography (OCT) for staging iris pigmented lesions in cats. Eighteen cats that underwent OCT examination for unilateral iris pigmented lesion were included. The cats were either suspected of melanosis due to clinical features (n = 8) or had been definitively diagnosed through histopathology with iris melanosis (n = 3), early feline diffuse iris melanoma (FDIM) (n = 4), or mid-stage or advanced FDIM (n = 3). From OCT images, mean iris thickness (MIT) was measured, and the ratio of pigmented lesion to normal iris (PN) was calculated. OCT images depicted the entire iris layer in all eyes with suspected melanosis, iris melanosis, and early FDIM, but observing the entire lesion in mid-stage/advanced FDIM was challenging. No significant difference in MIT was observed among the groups. Conversely, PN ratio was significantly higher (p < 0.05) in early FDIM (1.29 ± 0.16) than in suspected melanosis (1.02 ± 0.10) or iris melanosis (0.99 ± 0.09). Furthermore, OCT imaging revealed hyperreflective lines in 75% of eyes with suspected melanosis and in all the eyes with iris melanosis, corresponding to the pigmented lesions. Our results demonstrate that OCT is capable of detecting subtle differences in iris thickness and features in early-stage FDIM, indicating its potential utility in distinguishing between iris melanosis and early FDIM. Further study is warranted to verify the reliability of such OCT findings.

Feline restrictive orbital myofibroblastic sarcoma treated with toceranib phosphate (Palladia) as adjuvant chemotherapy: A case study of one cat.

Key Clinical Message: This is the first case report of treatment with toceranib phosphate as postsurgical adjuvant chemotherapy for advanced FROMS. This reported case highlights the need for further studies on the efficacy of toceranib phosphate as adjuvant chemotherapy for FROMS. Abstract: Feline restrictive orbital myofibroblastic sarcoma (FROMS) is a rare aggressive tumor in cats. We explored the effectiveness of using toceranib phosphate as postsurgical adjuvant chemotherapy for advanced FROMS in a 7-year-old cat. Despite treatment, the cat died 4 months after surgery. This report highlights the need for further studies on the efficacy of toceranib phosphate as adjuvant chemotherapy for FROMS.

Bilateral cataract surgery in a Japanese macaque (Macaca fuscata): A case report.

A 7.5-year-old intact male Japanese macaque was presented for evaluation of vision loss. After a complete ophthalmic examination, the patient was diagnosed with hypermature cataract in both eyes. After the cataract surgery, it was able to locate food and walk in a straight line.

Surgical treatment options for septic non-union of the tibia: two staged operation, Flow-through anastomosis of FVFG, and continuous local intraarterial infusion of heparin.

BACKGROUND: The treatment of septic non-union of the tibia is a challenging area.　The objective of this clinical study was to improve the treatment outcomes in patients with a highly active infection by the three strategies consisting of a two-staged operation, a flow-through technique for vascular anastomosis of a free vascularized fibular graft (FVFG), and continuous local intra-arterial infusion of heparin. PATIENTS & METHOD: Five patients with septic non-union of the tibia who were treated with an FVFG (mean age: 52.8 years) were enrolled.　The mean postoperative follow-up period was 47.2 months, and the mean length of the bone defect was 111 mm.　A two-staged operation, in which polymethylmethacrylate (PMMA) beads containing antibiotics were inserted into a bone defect followed by bone reconstruction performed with an FVFG later.　Vascular anastomosis was performed with the flow-through technique in all patients.　Immediately after FVFG, heparin was continuously infused through a femoral arterial catheter for 1 week. RESULT: Bone union was confirmed an average of 18.8 weeks after-surgery in all patients without reoperation for thrombus. CONCLUSION: Our attempt to apply the strategies appears to be a viable treatment option for septic non-union of the tibia.

Increased intramuscular pressure in lumbar paraspinal muscles and low back pain: model development and expression of substance P in the dorsal root ganglion.

STUDY DESIGN: The association between intramuscular pressure and low back pain was investigated by measuring intramuscular pressure and blood flow, assessing histologic appearance, and performing immunohistochemical testing in rats. OBJECTIVE: To develop an experimental rat model of increased intramuscular pressure (IMP) in the lumbar paraspinal muscles accompanied by reduced intramuscular blood flow (IMBF). The expression of neuropeptides in the dorsal root ganglion of the experimental model was also investigated. SUMMARY OF BACKGROUND DATA: Studies have reported that IMP in the lumbar paraspinal muscles is one of the causes of chronic low back pain. However, the pathology of low back pain accompanied by IMP has not been sufficiently clarified. METHODS: A balloon was inflated below the vertebral fascia of rats (balloon group) and intramuscular pressure and blood flow in the lumbar paraspinal muscles were measured. Intramuscular pressure was measured using a pressure transducer, whereas IMBF was measured using a contact-type laser Doppler flowmeter. Compared with the sham operation group, intramuscular pressure was higher and IMBF was lower for the balloon group at 1 hour and 1 day after insertion. In addition, at 1 hour and 1 day after insertion, IMBF and pressure were continuously measured while rats were positioned in flexion for 1 hour. RESULTS: Intramuscular pressure was significantly higher and IMBF was significantly lower in the balloon group at 1 day after insertion (P < 0.05). Expression of substance P, a neuropeptide, was also observed in the dorsal root ganglion of the first lumbar vertebra. CONCLUSION: These findings suggest that IMP and decreased IMBF in the lumbar paraspinal muscles induce inflammation and pain in the lower back.

Augmented cerebral activation by lumbar mechanical stimulus in chronic low back pain patients: an FMRI study.

STUDY DESIGN: Cerebral activation by lumbar mechanical stimulus was investigated by functional magnetic resonance imaging in healthy subjects and patients with chronic low back pain (LBP). OBJECTIVES: To characterize the cerebral substrates of LBP, and to explore a possible pathologic pattern of cerebral activation in chronic LBP patients. SUMMARY OF BACKGROUND DATA: The cerebral substrates of LBP have been poorly defined in contrast to those of cutaneous somatic pain. METHODS: Eight healthy volunteers and 6 patients with idiopathic, chronic LBP were recruited. Each subject was placed in the prone position on a 3 Tesla MRI scanner, and stimulated by manual pressure with the tail of an air-filled, 20-mL syringe at 5 cm left of the fourth-fifth lumbar spinal interspace. Three blocks of 30-second painful stimulus, calibrated at either 3 or 5 on the 10-cm visual analog scale (VAS), were applied with intervening 30-second rest conditions during whole-brain echo-planar imaging. VAS of pain intensity and unpleasantness were evaluated after each session. Functional imaging was analyzed using a multisubject general linear model with Bonferroni multiple comparisons at P < 0.05. RESULTS: Pain thresholds were smaller (P < 0.05) and VAS of unpleasantness was larger in LBP patients than in healthy subjects. Activation was observed at the prefrontal, insular, posterior cingulate cortices (PCC), supplementary motor, and premotor areas predominantly in the right hemisphere, but not at the somatosensory cortices. LBP patients showed augmented activation compared with healthy volunteers specifically at the right insula, supplementary motor, and PCC. CONCLUSION: Chronic LBP patients showed increased tenderness at the lower back, higher aversive reaction to pain, and augmented LBP-related cerebral activation. The LBP-related activation is characterized by the absence of sensory-discriminative component and the involvement of PCC.

Insertion of lateral mass screw of the atlas via the posterior arch: anatomical study of screw insertion using dry bone samples of the atlas from Japanese cadavers.

BACKGROUND: A new technique involving screw fixation of the atlas via the posterior arch and lateral mass has recently been reported for atlantoaxial instability. Because the posterior arch is thin, lateral mass screws risk penetrating the upper part of the posterior arch and damaging the vertebral artery running along the upper part of the posterior arch. METHODS: A total of 50 dry bone samples of the atlas from Japanese cadavers were used. We manually measured the shortest distance from the vertebral canal to the transverse foramen and the thickness at the thinnest part of the groove using calipers and investigated the frequency of dorsal ponticuli at the posterior arch. RESULTS: The area from the vertebral canal to the transverse foramen was thick enough to allow screw insertion, but the thickness of the posterior arch at the thinnest part of the groove was less than the screw diameter (3.5 mm) in 22% of vertebrae and <4 mm in 39%. A dorsal ponticuli was present in 10% of these samples. CONCLUSIONS: The size and shape of the posterior arch must be evaluated using radiography and computed tomography before inserting a lateral mass screw of the atlas via the posterior arch.

Nucleotide sequence and expression of the feline vascular endothelial growth factor.

Vascular endothelial growth factor (VEGF) is an angiogenic factor which targets vascular endothelial cells. In this study, cDNA encoding a feline VEGF (fVEGF) isoform was cloned from a feline lymphoid tumor cell line and sequenced. The fVEGF cDNA contained an open reading frame of 567 nucleotides coding for a polypeptide of 163 amino acids with a putative signal peptide of 26 amino acids. The predicted fVEGF amino acid sequence shared 98.4, 94.2 and 94.2% homology with the sequences of canine, bovine and human VEGF, respectively. Though predicted fVEGF polypeptide was two amino acid residues shorter than human VEGF165, a potential glycosylation site and regions critical for receptor binding were conserved in all the species examined. Transient expression of fVEGF in mammalian cells resulted in secretion of VEGF which could be detected by antibodies against human VEGF165. Furthermore, wide expression of fVEGF mRNA was observed in various feline tissues using RT-PCR methods.