A comparative study between preoperative and postoperative pulmonary functions and diaphragmatic movements in congenital craniovertebral junction anomalies.

Respiratory dysfunctions in patients with craniovertebral junction (CVJ) anomalies may occur due to compression of brainstem affecting the respiratory centers, and weakening of the muscles of respiration. We assessed pulmonary functions [forced vital capacity (FVC), forced expiratory volume in first second (FEV1), maximum mid-expiratory flow rate (FEF25%-75%), FEV1%], mouth pressures (maximum inspiratory pressure, maximum expiratory pressure), and diaphragmatic movements in 30 patients of CVJ anomalies and compared them with their mean predictive values. These parameters were also assessed in the postoperative period. It was found that the mean values of FVC, FEV1, and FEF25%-75% were significantly lower (P<0.001) than their mean predictive values (2.4+/-0.8 L, 2.0+/-0.7 L, 2.5+/-0.9 L vs. 3.7+/-0.9 L, 3.2+/-0.7 L, and 3.4+/-0.7 L, respectively). In the postoperative period there was significant reduction (P<0.05) in all these parameters (2.2+/-0.8 L, 1.7+/-0.7 L, and 2.1+/-0.8 L, respectively). The postoperative FEV1% was 78.8% compared with the preoperative value of 85.7%. A restrictive pattern of lung disease was observed which persisted in the postoperative period. The postoperative maximum inspiratory pressure and maximum expiratory pressure were comparable to their preoperative values (47.9+/-19.6 and 47.0+/-16.7 cmH2O vs. 42.6+/-17.3 and 43.9+/-18.2 cmH2O, respectively). Similarly, the diaphragmatic movements were also comparable to the preoperative values, both during quiet and deep breathing (13.7+/-3.9 and 38.0+/-9.3 mm vs. 13.8+/-3.9 and 39.0+/-9.1 mm, respectively). There was no improvement of pulmonary functions in the early postoperative period. However, a long-term follow-up is needed to determine subsequent changes of these parameters.